Homer Hickam Speaks Out For Fission Rockets

jonerik writes: "Former NASA engineer Homer Hickam (perhaps best known for his 1998 memoir "Rocket Boys," which was turned into the 1999 motion picture "October Sky") has this article in Technology Review in which he advocates that the U.S. revive its nuclear rocket program of the '50s and '60s, arguing that nuclear-powered rockets are the only realistic way of opening up the rest of the solar system - particularly Mars - to human exploration."

Comments

Plasma/Laser Powered Rockets

[beninkster]

The pulsed laser rockets that are currently being developed offer some serious promise as well. http://www.islandone.org/LEOBiblio/SPBI115.HTM

Re:Plasma/Laser Powered Rockets

[spike hay]

Here is a link to that : here

Anyway, nuclear rockets are a great idea. A better one, you may have heard me harp on this before, is VASIMR. It is a plama rocket with a nuke power source. It will be around ten times as efficient as the nuke rockers. However, the VASIMR, unlike the nuclear rocket, it does not have enough thrust to launch from earth. It is more a slow and steady engine that runs for weeks instead of minutes. But the burnout velocity of a VASIMR can be vastly higher than a chemical rocket.
The nuclear rocket can provide cheap, efficient space launches with not too much radioactive fallout. In fact, if a nuclear rocket using helium as a propelent will produce no fallout at all. Since a nuclear rocket is about twice or three times as efficient as a chemical rocket, the amount of fuel you'd need would be slashed dramatically. A nuke rocket launch might only use 10% or less of the fuel that a conventional booster would.

It's under R&D.

It ionizes hydrogen with microwaves an then accelerates them with magnetic fields. While it doen't provide thrust like a chemical rocket, it certainly has many, many times more thrust than a ion engine. It has some oomph to it. For cheap launches, you really need somthing like the x-42 scramjet spaceplane. That would cut costs of launching by a factor of 10 with no giant lasers.

VASIMR will get a specific impulse of 30,000 seconds compared to 500 seconds for the shuttle's engines. A specific impulse is the number of seconds 1 kg. of fuel could produce 1 kg. of thrust. The specific impulse of the VASIMR is 60 times better than the shuttle. That is many times better than the ~1500 seconds you'd get with the nuclear rockets.

That would allow cheap interplanetary voyages anywhere in the solar system, using very little fuel. Using these engines, you could get to Saturn in less than a year. It would also allow slow intersteller trips of around 1% the speed of light.
Also, VASIMRs could be easily, cheaply, and quickly refueled for more missions.Interplanetary travel could become cheap. I bet each ship would cost around 5 billion dollars initialy. After that, it's cheap. After each trip, an X-42 could come and restock the ship with fuel and supplies. That would only cost around 50 million. We could send tens of thousands to colonize Mars.

BTW: On this article, it says the VASIMR gets 10,000 seconds. It can reach 30,000 with further development.
Read about the VASIMR here
--

Re:Plasma/Laser Powered Rockets

[Anonymous Coward]

Try to ignore my glaring spelling errors. :)
nuke rockers

Re:Plasma/Laser Powered Rockets

[ftac]

It ionizes hydrogen with microwaves an then accelerates them with magnetic fields. While it doen't provide thrust like a chemical rocket, it certainly has many, many times more thrust than a ion engine.

What? why ionize hydrogen? It's so light. Ion thrusters use the heaviest inert gas viable: Xenon, in order to get any reasonable thrust as all.

A specific impulse is the number of seconds 1 kg. of fuel could produce 1 kg. of thrust.

thrust is measured in Newtons.

This VASIMR thing sounds like a microwave MPD, with a nuclear power source. The question is: why lug a massive nuke power supply when you have the Sun? In terms of Amperes per kg, IMHO solar panels are much cheaper than a nuke reactor.

Re:Plasma/Laser Powered Rockets

[jonerik]

This VASIMR thing sounds like a microwave MPD, with a nuclear power source. The question is: why lug a massive nuke power supply when you have the Sun? In terms of Amperes per kg, IMHO solar panels are much cheaper than a nuke reactor.

True, but only up to a point. As you get further from the sun, the amount of light that the solar panels collects decreases, so you need to either attach more solar panels, reduce power consumption, or find another power source. Solar works well for missions to the rocky inner planets, but once you're out past Mars there's less and less light to collect. If you're talking about sending men to, say, Titan, solar won't cut it.

Re:Plasma/Laser Powered Rockets

[praedor]

When you start getting out to Jupiter and beyond, the Sun is not a viable power source. For deep space you MUST have nuclear power. There is NO deep space probe that isn't nuclear powered. None. You want to get to the outer solar system efficiently and quickly, then you want/need nuclear. Also, solar isn't worth squat to astronauts on the Martian surface. Inefficient. You send a portable nuclear power plant (no, no it CANNOT meltdown damnit!) and have LOADS of power available to keep you alive and warm AND producing fuel for a return trip.

True space travel and exploration will require nuclear power if you are heading outward.

Re:Plasma/Laser Powered Rockets

[Anonymous Coward]

How does the specific impulse of the VASIMR compare to that of an ion engine? For long trips, that's far more relevant than the thrust.

Regardless of the specific technology used, I agree that a nuclear power source makes far more sense than chemical fuels.

Re:Plasma/Laser Powered Rockets

[Anonymous Coward]

My grandpa came up with an idea that utilized a first stage laser lifting *Jet*.The idea is that the lifting body

contains *neither* the reaction mass or a source of power.

.

The jet would be a tube with windows that allowed shafts of trans blue laser light to

enter, to react with a black body radiator, within, converting laser light into heat on a

most efficient basis. Since all laser emminations react with air producing losses,

optimal wavelengths would be used to travel to the jet, then converted into heat to

operate a standard ramjet configuiration. Because the system looses efficiency as the

beam heats the air through which it passes, by converting a single hi powered beam into

numerous tiny beams diminishes various misalignment factors.These fractional beam

would converge through a window in the jet. A number of *Beowulf clusters* of these beams

would create a track that the jet would spiral upward above. Such a jet might operate to 100

miles hi with special air scoops.

.

Focus of the laser is becoming more probable with

hi speed computatioal systems to converge 100's of beams into a window many miles up.

The focal efficiencies that one would be willing to operate at wiil determine the height to

which it will operate & its component's costs. *Jet*.The idea is that the lifting body

contains *neither* the reaction mass or a source of power.

.

The jet would be a tube with windows that

allowed shafts of trans blue laser light to enter, to react with a black body radiator,

within, converting laser light into heat on a most efficient basis. Since all laser

emminations react with air producing losses, optimal wavelengths would be used to travel

to the jet, then converted into heat to operate a standard ramjet configuiration. Because the system looses efficiency as the

beam heats the air through which it passes, by converting a single hi powered beam into

numerous tiny beams diminishes various misalignment factors.These fractional beam

would converge through a window in the jet. A number of *Beowulf clusters* of these beams

would create a track that the jet would spiral upward above. Such a jet might operate to 100 miles hi with special air scoops.

.

Focus of the laser is becoming more probable with

hi speed computatioal systems to converge 100's of beams into a window many miles up.

The focal efficiencies that one would be willing to operate at wiil determine the height to

which it will operate & its component's costs.

How else would you open up the solar system...

[kenthorvath]

... besides with a Big Bang?

Re:How else would you open up the solar system...

[doooras]

i'm not sure if by "Big Bang" you mean a fission explosion or the beginning of everything... either way, it's funny.

Re:How else would you open up the solar system...

[kenthorvath]

I suppose it was meant to be ambiguous...

Unfortunately

[scientology]

To propose that we spend more money on NASA (with cutbacks already planned), the "nuclear fission" rocket may just be a pipe dream. It's hard to convince people that we need to explore space when the topic of the day is terrorism.

Re:Unfortunately

[BigBlockMopar]

To propose that we spend more money on NASA (with cutbacks already planned), the "nuclear fission" rocket may just be a pipe dream. It's hard to convince people that we need to explore space when the topic of the day is terrorism.

Well, they go hand in hand. The technology from space exploration affects our lives in thousands of big and small ways every day. The integrated circuit was first mass-produced for space exploration reasons. And it's a lot easier to peel my fried eggs off Teflon than it is off cast iron.

Any advance in getting the general public to get over their Three Mile Island and Chernobyl paranoia will require nuclear-powered triumphs.

Idiot hippy environmentalists speak of cutting dependence on (foreign) oil by moving to electric cars. That'd be nice. How do you intend to handle California's power crisis (remember, 2 years ago) when 10,000,000 Los Angeles commuters are plugging in their cars every night?

The very same environmentalists who scream about oil and air pollution are also at the mass rallies to ban genetically-modified agriculture. GM corn is probably the most economically feasible way, at this point, to make large quantities of methanol, which could replace gasoline very easily, simply retrofitting existing vehicles and infrastructure. These people also scream that we have to solve world hunger before we feed our cars. (My opinion? Theses savages are stupid enough to breed when they can't feed themselves, let alone their larvae. It doesn't take education or literacy to understand the problem; a below-average human intelligence should readily grasp the situation. It's not my problem, and I resent you attempting to make it my problem.)

Tidal/Solar/Wave power? Sure, they're neat science fair projects for the kiddies, but they're simply not capable of contributing substantially to our energy needs for the forseeble future.

Nuclear power is the only viable solution. And the proles have discarded it because they're too simple to understand that blaming nuclear power for Chernobyl would be like blaming gasoline for a car accident. Chernobyl, Three Mile Island and the vast majority of car accidents are caused by imbeciles, not the fuel source.

What's all this got to do with terrorism? Simple. The sooner we get off foreign oil, the sooner we can dig a moat around the Middle East and let them do their thing in isolation from the civilized world. And if funding NASA to build huge nuclear public-relations projects which will inevitably bring us other technologies as a consequence, I'm all for it.

Go ahead. Mod me down. But I'm right, and all the politically-correct simpering you might want to do won't change the facts.

Re:Unfortunately

[mike_g]

Teflon's invention is not related to the space program. Integrated circuits were not first mass produced for space exploration. They were first mass produced to control ballistic missles. While this is similar to rockets used for space exploration the intent was not to make scientific discoveries, it was to be able to deliver a nuclear weapon payload anywhere in the world.

While I do appreciate NASA, I think that the department of defense has had a much larger technological impact on our lives (digital computers, IC's, internet among other things).

Re:Unfortunately

[sgage]

"My opinion? Theses savages are stupid enough to breed when they can't feed themselves, let alone their larvae. It doesn't take education or literacy to understand the problem; a below-average human intelligence should readily grasp the situation. It's not my problem, and I resent you attempting to make it my problem."

etc., etc., ad nauseam.

Oh boy, another highschool kid discovers Ayn Rand! I was going to respond to several of your confused points, but there's nothing quite coherent enough to deal with. So instead, here's some simpering for you: sticking your head up your ass won't change the facts.

Re:Unfortunately

[MtViewGuy]

I think people have WAY too many misconceptions about nuclear power.

For one thing, the Chernobyl nuclear plant was a disaster waiting to happen. Between the dangerous design of the reactor and the fact there was no containment dome, no wonder the disaster was so bad.

The Three Mile Island accident was proof that Western nuclear plant designs worked. Note that even though the fuel rods partially melted down the containment dome was nowhere close to being breached; the radioactive release was equivalent to the radiation dose you get on a single five hour trancontinental flight from Los Angeles to New York at 30,000 feet.

By the way, our nuclear waste problem is minor compared to the former Soviet Union, where they actually stored nuclear waste in open pits for many years. (eek!)

Re:Unfortunately

[Anonymous Coward]

Yeah, the fact that all the safety systems were switched off really didn't help Choernobyl either.

Re:Unfortunately

[Anonymous Coward]

The fact that you COULD switch off all the safety systems, which would then lead to a core meltdown, is an indication of bad reactor design.

Design the damn thing so that when you start switching off control systems it shuts itself down. That's how US reactors are done.

Re:Unfortunately

[WoodsDweller]

• Idiot hippy environmentalists speak of cutting dependence on (foreign) oil by moving to electric cars. That'd be nice. How do you intend to handle California's power crisis (remember, 2 years ago) when 10,000,000 Los Angeles commuters are plugging in their cars every night?

Roughly 95% of petroleum use in the US is for transportation, and roughly 98% of the transportation system is powered by petroleum. Switching to electric (really, fuel cells, since lead/acid batteries do not have the power to weight ratio to build the kind of vehicles we want/need to have) does eliminate (or nearly so) the need for petroleum, foreign or domestic. But it does create a need for massive increases in electricity production, as you point out. So we would need to add a lot of solar capacity.

• GM corn is probably the most economically feasible way, at this point, to make large quantities of methanol, which could replace gasoline very easily, simply retrofitting existing vehicles and infrastructure.

Actually, I believe it is ethanol that is produced, and then denatured with a small amount of methanol.

While I have not seen any figures on the amount of land it would take to produce that much extra grain, it would clearly be substantial, and our grain surpluses together with the land in CRP (Crop Rotation Program) would likely not be enough to equal the 20 million barrels of petroleum the US consumes daily. I have also read that producing ethanol takes more energy than is present in the fuel produced, probably for distallation. That would make the ethanol a secondary fuel, not a primary one.

• Tidal/Solar/Wave power? Sure, they're neat science fair projects for the kiddies, but they're simply not capable of contributing substantially to our energy needs for the forseeble future.

You may be right with regards to tidal power.

Wind power is already being added to the grid in many places (one plant in my state of Colorado, another is planned, lots of capacity being added in Texas). It is cost effective today. Adding large amounts of unbuffered wind power to the grid mix is not feasible because of fluctuations in the production. So, we need to buffer it! Crack water with the wind power, run the grid from fuel cells.

Solar works. Today. This post is being made with solar energy. There is exactly one problem: it is more expensive (by 10x or so) than we are used to paying for electricity.

• Nuclear power is the only viable solution.

Fission power works. But for how long? And at what cost?

If we were to switch the US to fission power completely (including powering the transportation system), and continue to use uranium fuel without reprocessing, we would be out of fuel before the plants were all built, let alone depreciated. Reprocessing the fuel would add another 40 or 50 years to the supply. Even if you consider breeder reactors, you get another 1000 years or so of energy. Then what?. Solar will be present for as long as Earth is a viable place to live.

Radioactive waste is produced by and for nuclear plants. It lasts for a long time. It cannot be disposed of. It must be stored until it decays. That takes, for the high level wastes, geologic time. I am sceptical that we can build storage facilities that are secure for 10 times the age of the pyramids. We simply do not have that sort of track record.

Re:Unfortunately

[zulux]

Oh boy, another highschool kid discovers Ayn Rand!

That not civil - to attack the man and not his ideas. How about this for fair play:

Oh boy, another trust fund state school university kid discovers Noam Chomsky.

Re:Unfortunately

[BigBlockMopar]

For one thing, the Chernobyl nuclear plant was a disaster waiting to happen. Between the dangerous design of the reactor and the fact there was no containment dome, no wonder the disaster was so bad.

One idiot (while driving the stereotype poorly-tuned oil-burning VW Microbus and pretending to be an environmentalist) was telling me all about how sorry we'd be when Pickering (a CANDU-design nuclear plant outside Toronto) "goes Chernobyl".

Ahhh, yes. That would deny the fact, of course, that deuterium water is required as a moderator for U-238 to fission. And that when the reactor overheats, a pipe will burst somewhere and all the moderator (very expensive water) will escape as steam. And that, without the moderator, the reactor will cease to produce heat.

Instead, we're going to have tonnes of (solid, non-evaporating) graphite blocks with U-235 rods glowing red-hot within, belching smoke and radioactive dust across Toronto, all coming from a reactor which doesn't have any of these critical design flaws?

I told him to stop voting until he stopped smoking up.

Re:Unfortunately

[ryanwright]

So instead, here's some simpering for you: sticking your head up your ass won't change the facts.

I found his post insightful and dead-on accurate. You, on the other hand, fail to make a single argument. You talk about the "facts" but won't even define what they are.

Nothing quite coherent enough to deal with? Hell, you provided nothing at all to deal with. Next time, try saying something.

Re:Unfortunately

[Deskpoet]

These people also scream that we have to solve world hunger before we feed our cars. (My opinion? Theses savages are stupid enough to breed when they can't feed themselves, let alone their larvae. It doesn't take education or literacy to understand the problem; a below-average human intelligence should readily grasp the situation. It's not my problem, and I resent you attempting to make it my problem.)

This is *precisely* why human beings should be confined to this planet: this "compassionate conservative" wants to spread his "it's not my problem" immaturity to the stars, where it'll be free to destroy everything it doesn't understand or can't empathize with.

We really are a pathetic collection of evil nothings. Best outcome: the nukes do us all in, and the dolphins take over the top of the food chain.

"Go ahead. Mod me down. But I'm right, and all the politically-correct simpering you might want to do won't change the facts."

Re:Unfortunately

[BigBlockMopar]

This is *precisely* why human beings should be confined to this planet: this "compassionate conservative" wants to spread his "it's not my problem" immaturity to the stars, where it'll be free to destroy everything it doesn't understand or can't empathize with.

I resent and reject both the terms "compassionate" and "conservative".

I am a Libertarian by nature, and I like to let people celebrate the triumphs of good decisions and hard work, whilst suffering the perils of poor decisions and laziness, with an absolute minimum of government intervention.

Being called conservative is, frankly, offensive. Too often, conservative politics run synonymously with religion. And, of course, religious faith is symptomatic of a paranoid-delusional disorder. It terrifies me that George Dubya and Trent Lott really think that an invisible man watches them while they sit on the john, and instead of being locked up in a rubber room, they're elected to office.

Empathy? Well, I'm sure that it hurts being on the wrong side of Darwin, but it's not my fault. It's not my fault that HIV-infected Ugandan tribesmen think they can be cured by sleeping with a virgin. It's not my fault that all of Bangladesh is located on India's sewer (Ganges River) and that the whole country is doomed to frequent floods because it's barely above sea level. And it's not my fault that these savages in the Middle East are killing each other because of a warped game of "My Paranoid Delusional Fantasy Is Better Than Your Paranoid Delusional Fantasy". On September 11th, that one *did* become my problem, and while I thoroughly empathize with the needs for psychiatric treatment for religious people everywhere, like dealing with a rabid dog, euthanasia is an attractive and practical alternative.

Best outcome: the nukes do us all in, and the dolphins take over the top of the food chain.

Uh-huh. Tell that one to my tuna sandwich.

Re:Unfortunately

[PaulGibson]

Oh yes, energy policy brings out the best in everyone. First of all, we make dicisions based on the wrong thing: money. This way public good is moved aside for corporate greed. This has been going on since at least the 50s when we decided to use nuclear power over wind power. Back then, the cronies touted nuclear power as the cleanest and cheapes source possible. So, when they got done smoking and listening to their Marley tunes, they got to work building the reactors. Since then, nuclear power (about 17% of US power consumption) is by far the most expensive, even without including the costs incurred when dealing with the waste. Wind power, alternatively, could have produced 100% of US power consumption, with the problem being one of continuity . . . easily solved had we been motivated to do the right thing.

On the other hand, lets just understand that Whatever path we take, there will be periods where we have to backtrack and rethink. Look at a future where all cars run on fuel cells that spew O2 and H2O. When I was studying the atmospheric balance it seemed that if our O2 levels were raised by as much as 10%, the atmosphere would become far too volitile for most life here. So, no matter what polutants we spew, whether we think of them as good or bad, we risk upsetting a very fragile balance. Our goals as a society should be, IMHO, to live quietly on this planet. To learn all we can, but to leave the ecosystem largely alone. Find a way to power transportation and living systems that does not change the local or global ecosystems, and until we do, minimize the damage as much as possible. Until $ is not the almighty last word, we will continue to do what is good for the likes of Kenny Boy, and what is bad for every other living thing.

no one carries the dog boy

Re:Unfortunately

[Anonymous Coward]

These people also scream that we have to solve world hunger before we feed our cars. (My opinion? Theses savages are stupid enough to breed when they can't feed themselves, let alone their larvae. It doesn't take education or literacy to understand the problem; a below-average human intelligence should readily grasp the situation. It's not my problem, and I resent you attempting to make it my problem.)

You're refering to the environmentalists, right?

Re:Unfortunately

[Anonymous Coward]

Is this a joke? and who modded this as "informative"?

Re:Unfortunately

[Anonymous Coward]

fuel cells "spew" O2 and H2O??????
Whathafsck YOU smokin' bud?
H2 and O2, the latter from that dangerous stuff called "AIR", combine in a fuel cell to produce that even more dangerous diHydrogenMonoxide!
In two forms no less, a dangerous fluid in droplet form and as a gaseous vapor.
You might want to consult a high school science text on this dangerous, even toxic material!

Good Idea, just won't happen anytime soon

[sigep_ohio]

He is 100% correct in his assessment that nuclear power is our only currently viable option to explore the rest of the solar system.

Unfortunately, people are so freaked out about anything with the word "nuclear" or "reaction" attached to it the only way they would ever put a dime in it is if it was called "The Wonder Drive" or "Warp Drive". The really sad part about that is nuclear powered rockets really wouldn't be that dangerous. The most dangerous part about them would be getting the fuel off planet, which is not as dangerous as it sounds.

Re:Good Idea, just won't happen anytime soon

[Anonymous Coward]

I think it should be called "The Great Mushroom Shooting Rainbow Fun Machine".

Re:Good Idea, just won't happen anytime soon

[Anonymous Coward]

Nucular.

It's pronounced 'nucular.'

Re:Good Idea, just won't happen anytime soon

[Ian Bicking]

When someone first thinks about nuclear waste, one of the first reactions is, "why not just launch it into space?" I haven't happened to come upon the argument against it, but I imagine it goes like: sending stuff into space is far more expensive and polluting than people imagine.

But this would be perfect -- sure, you'd be making more nuclear waste, but you'd be sending it into space in the process! That's not hard to understand.

I think there is every reason to worry about dangers, though. Rockets do blow up (with current technology) and if they had radioactive materials onboard that would mean many, many deaths (mostly indirectly through increased cancer).

I imagine that nuclear rockets could be considerably safer than chemical rockets, since my vague impression is that they wouldn't be as explosive. But many of the standard ways that nuclear reactors are made safe -- mostly through containment of various sorts -- would be hard to do in a rocket.

Re:Good Idea, just won't happen anytime soon

[zerocool^]

Unfortunately, people are so freaked out about anything with the word "nuclear" or "reaction" attached to it ...

News flash, public: The Sun, our source of life and energy, is "Nuclear". In fact, it's just one big "Reaction".

To quote TMBG, "The sun is a mass of incadescent gas, a firey nuclear furnace, where hydrogen is built into helium at temperatures of millions of degrees."

~z

Re:Good Idea, just won't happen anytime soon

[Fjandr]

I imagine that nuclear rockets could be considerably safer than chemical rockets, since my vague impression is that they wouldn't be as explosive. But many of the standard ways that nuclear reactors are made safe -- mostly through containment of various sorts -- would be hard to do in a rocket.

Not in regards to being explosive. The fission is used to heat a propellant material, such a hydrogen, which is readily ignited, and can explode under many circumstances.

Re:Good Idea, just won't happen anytime soon

[eddy the lip]

Unfortunately, people are so freaked out about anything with the word "nuclear" or "reaction" attached to it...

Nah, you just need to make sure you get the word "tactical" stuffed in there. It's safe if it's only tactical.

Re:Good Idea, just won't happen anytime soon

[Fjandr]

Well, safe being relative. :)
Most tactical nukes use weapons-grade fuel, which radiates alpha particles. Now, the crude bombs tend to use the fuels that react easily, but those emit gamma radiation, which is the stuff that punches countless tiny holes in your cells. It just takes a while for your brain to realize you're dead.

Re:Good Idea, just won't happen anytime soon

[abe ferlman]

News flash, public: The Sun, our source of life and energy, is "Nuclear". In fact, it's just one big "Reaction".

SO as long as you don't launch the rocket until it's as far away as the sun, we've got nothing to fear but sunburn itself.

Re:Good Idea, just won't happen anytime soon

[zerocool^]

no +1 bonus, off topic:

I just wanted to say i really admire your quote. Very classy of you. I have read LOTR about 12 times now, and actually i have a test on the silmarillion tomorrow in my science fiction / fantasy class - it's an english class - heroic fantasy: beowulf thru tolkien. Anyway, good work, and I'm happy with myself that I know exactly where that quote comes from.

Re:Good Idea, just won't happen anytime soon

[wmaheriv]

How about this one: what if the rocket laden with nuclear wastes explodes in the atmosphere? Not all that likely, but it has happened, several times. Can you imagine a humungous "dirty bomb" detonated above the Eastern US? I can, and it's frightening enough that I hope no one ^ever^ sends fission wastes into space.

Re:Good Idea, just won't happen anytime soon

[Richthofen80]

I applaud your post. But don't limit yourself to nuclear paranoia just for spaceships. There's still a lot of squalking about the facility in Nevada to store terrestrial nuclear waste. There's just too much politically associated with bad things like three mile island, etc. People demand we cut consumption of fuel, but don't want to take a relatively cheap / efficent / clean fuel like nuclear power.

Nuclear power could solve lots and lots of energy problems, and really bring down total cost of electricity. Plenty of nations have nuclear power as their primary source of electricity (france, for instance). If electricity prices really dropped, and battery technology got better, we could finally have lots of electric cars. Lots of electric cars means we could break the grasp of OPEC and all those other nations which control U.S. interests in oil. All I see in nuclear power is profit for everyone.

And, because i know it's coming, a rocket, laden with radioactive material, that explodes and scatters nuclear waste, would probably increase cancer rates about as much as the huge plumes of smoke that we dump into our atmosphere by burning all those chemicals to get into space using conventional fuels.

Re:Good Idea, just won't happen anytime soon

[eddy the lip]

Fine - you keep it in your bedroom ;)

Now, I didn't have time to research this properly, but a quick trip to google turned up this (from a study on alpha particle emissions from radon gas):

"Our observations negate pre-existing assumptions that alpha particles like those emitted by radon and radon progeny exert their genetic changes exclusively through direct traversals of cell nuclei," said project leader Bruce Lehnert of Cell and Molecular Biology (LS-4). "Accordingly, current dosimetry models upon which environmental standards for radon exposure are derived now require serious reconsideration. Our work suggests that even interactions of alpha particles with the fluids that line the lungs may lead to alterations in the DNA of nearby cells."

which sounds to me like alpha particles have their own special way of screwing with your DNA. But this isn't really my field....

(And just so as not to be misunderstood by the idle reader, I've got nothing against nuclear rockets, just rockets with nukes).

Re:Good Idea, just won't happen anytime soon

[abe ferlman]

Yeah, it's sweet. I was a little disappointed that that line was stripped from the movie, but since they show her wearing it in the beginning I suppose it's an acceptable abridgement :)

BTW, if you are at all into roguelike games (or have never tried them), you should try Angband. It's a very fun Tolkien-based ascii-graphics game that's been around for well over a decade and has been developed more or less actively for pretty much all of that time. You can find Nenya very, very deep in the dungeon. But it's pretty damned tough if you don't cheat (i.e., restore a dead character from a savefile). You can almost certainly find a version for your platform at ftp://ftp.sunet.se/pub/games/Angband/.

Ah well. Back to the rockets I suppose.

Re:Good Idea, just won't happen anytime soon

[Mahonrimoriancumer]

Before freaking out over doomsday myths that the media and radical enviromentalists claim about anything related to nuclear power, think about this.
Most radioactive particles would remain airborne for weeks to years before reaching the ground. By that time their extremely wide dispersal (many smaller particles would be carried by the winds for tens to thousands of miles before falling to earth) and radioactive decay would make them much less dangerous. Only where such tiny particles are promptly brought to earth by some sort of precipitation and later dried and blown about by the winds, would these invisible particles constitute a long-term and relatively minor danger.

Re:Good Idea, just won't happen anytime soon

[Fjandr]

Oh, I didn't mean to imply alpha particles don't damage genetic material, except that human skin easily blocks alpha particle transmission, so it's not an external radiation risk. Now, if you were to consume a material that emits alpha particles, you'd be in some trouble.
And I'm not defending nuclear weapons or nuclear rockets, simply clearing up some misconceptions. :)

Re:Good Idea, just won't happen anytime soon

[Fjandr]

Oh, as an aside about that article, they're talking about radon, which is a gas. That's why it poses a specific radiation danger, because it's an internal radiation hazard, being easily inhaled. :)

Re:Good Idea, just won't happen anytime soon

[silentbozo]

Unfortunately, people are so freaked out about anything with the word "nuclear" or "reaction" attached to it the only way they would ever put a dime in it is if it was called "The Wonder Drive" or "Warp Drive".

Absolutely right. That's why they use MRI (Magnetic Resonance Imaging) to describe what used to be known as Nuclear Magnetic Resonance Imaging (NMRI.) The nuclear in this case refers to the nucleus of the atoms/molecules being imaged by the scanner. NMRI is a more descriptive name for the technique, but it's bad form to mention "Nuclear" to patients when you need to do a scan.

Re:Good Idea, just won't happen anytime soon

[geo_flux]

We have the same problem in Australia. Over here there has been talk of creating a low level nuclear waste dump in the remotest part of South Australia to store all the nuclear waste that is currently in hospital and university basements around Australia. Unfortunately as soon as the public found out there were cries of 'not in our backyard' etc etc. Apparently most people would rather have nuclear waste spreadout throughout the entire country instead of putting it all in one remote place. Go figure

Re:Good Idea, just won't happen anytime soon

[fdicostanzo]

When I was there, I found indigenous people everywhere in the desert. I don't think anywhere is really "remote", unless one just means from themselves.

Re:Good Idea, just won't happen anytime soon

[Anonymous Coward]

Plus FIVE? Give me a fucking break!

Re:Good Idea, just won't happen anytime soon

[Anonymous Coward]

The propellant material can be anything, even if article mentioned hydrogen.

Re:Good Idea, just won't happen anytime soon

[kronstadt]

When there's a failure during launch and the uranium containment chamber is blown to pieces in the atmosphere, how would you explain to some kid in Africa why all of his relatives are getting cancer from fallout. Sure, chances are that the rocket will make it, but what if it doesn't?

"Well, we really wanted to go to space and we did some testing first. Apparently we were in the wrong 1% of the failure rate. Oops!"

The moral crux (for me) is that our decision to satisfy a desire to go to space has global implications. Don't get me wrong, I'd love to see more space exploration. At the same time, however, I don't see how it's legitimate for a small group of people to make the decision to risk every one else's lives, no matter how small the risk.

Re:Good Idea, just won't happen anytime soon

[SoLoatWork]

This is why the launch should be from a remote pacific island near the equator. I'm sure the U.S. owns some territory out there in the middle of the ocean.

Re:Good Idea, just won't happen anytime soon

[eddy the lip]

Ah, that all makes good sense...thanks for the info...

Re:Good Idea, just won't happen anytime soon

[Storm Damage]

It's called the Bikini Islands...

Why don't we just turn the rest of the stars on their flag black? After all, what's another half a $billion?

Re:Good Idea, just won't happen anytime soon

[Cally]

> Unfortunately, people are so freaked out about
> anything with the word "nuclear" or "reaction"
> attached to it the only way they would ever put a
> dime in it is if it was called "The Wonder Drive"
> or "Warp Drive"

Fiddlesticks. People's fears of nuclear power are - well OK most people's fears are pretty irrational, but then that's humans for you - but nuclear power IS phenomenally dangerous and Bad, as only a cursory examination by anyone not blinkered by obsessive techno-fetishism, or with a mind decomposed by reading too much crap SF would tell you.

Re:Good Idea, just won't happen anytime soon

[Fjandr]

Yes, it could be methane, it could be oxygen...
Nearly all of the materials that have a current-tech application are also highly dangerous.

Re:Good Idea, just won't happen anytime soon

[Skip666Kent]

Make that, "The eXtreme Great Mushroom Shooting Rainbow Fun Machine".

Re:Good Idea, just won't happen anytime soon

[AutumnLeaf]

Research on putting nuclear fuel into space (and the sun) has been performed. It was my undestanding from a science show I saw on TV (Discovery channel or something) that we can't launch nuclear waste into space due to treaty obligations.

The technical problem of containing the waste safely in the event of a catastrophic (is there any other kind?) launch event was pretty much solved. Cannisters strong enough to withstand impact with the earth were engineered, built, and tested. They were tested by mounting them on cars, which were on rails, putting jet rockets on them to accelerate them to impact speeds, and slamming them into 64' cubes of reinforced concrete. The concrete blocks MOVED! The containers maintained their integrity.

The only counter-argument to the waste-in-space idea that I've seen that seems to have merit is the weight of the substance. Especially with respect to any container holding it. Still, I think it's a solvable problem. It could be expensive to get all of our waste in space, but what are the consequences of leaving it around for centuries upon centrues?

Also, don't forget space isn't the only option. Breeder reactors can refine most if not all radioactive waste from fission reactors and reduce their radiactivity back to normal ground levels, thus allowing them to simply be buried. Some waste can be refined and re-enriched enough to be re-used via a breeder reactor as well.

Re:Good Idea, just won't happen anytime soon

[Anonymous Coward]

Unfortunately, people are so freaked out about anything with the word "nuclear"

Amen, brother! The image that comes to mind is a Jane Fonda type with a cigarette picketting a fission power plant while getting more radiation from the cigarette than from the plant.

Which is not to say that there aren't legitimate concerns. Any large power plant presents potential environmental, health and safety hazards if not properly operated, and the NRC has been worse than lax in its supervision. Nuclear poser is dangerous, almost as dangerous as coal or LNG power.

Doh!!!

[Anonymous Coward]

Doh!!!

Radiation

[zaffir]

He makes a point about radiation being one of space's harmful effects. If we can't keep the sun's radiation away from our astronauts, how do we keep the reactor in the rocket from irradiating the crew?

Re:Radiation

[Laven]

How do you keep the reactor of the submarine or the aircraft carrier from irradating the crew?

I'm sure they have figured that out long ago.

Re:Radiation

[Anonymous Coward]

Lead.

Re:Radiation

[zaffir]

You missed my point. Sure, they can do it here on earth, but we don't have to haul that protection into space. It would make sense for NASA to line the ship with lead, but imagine having to carry all that into space. If i remember correctly, a good part of a sub's weight is protection from the reactor (i could be wrong on that, however). Having to lug all that into space would be very expensive, even compared to today's space flight costs.

Re:Radiation

[Anonymous Coward]

Actually, I beleive in a sub there is no penalty for the shielding; they would be carrying that weight in ballast anyway. Simular arguments may apply to a ship (you'd want the reactor as close as possible to the bottom of the ship). However, in a rocket where every pound costs you $10,000 to get into orbit, there is a substantial penalty. I think the real solution is to, instead of carrying reaction mass with you, find some way to gather up and accelerate the particles found in open space. Yes, beaming energy to the ship may help get you into orbit, but it doesn't help you much once you get any distance away from earth. Solar sails, anyone?

Re:Radiation

[Anonymous Coward]

You are forgetting your Astro-Physics.

The radiation coming off the reactor is negligible compared to the stellar and interstellar radiation we already need to shield humans against.

Space isn't a void like hollywood likes to glamorize. There's a whole lot of nastiness out there (solar wind, gamma rays, etc), and it only gets worse once you get out past Jupiter.

Re:Radiation

[doubleyou]

Worse? I would think it gets better the further out you get. The most intense source of radiation in the solar system is at its center. Or am I missing something...

Re:Radiation

[Aglassis]

In space you could simply increase the distance from the reactor to the life support areas by use of a metal truss like structure. The radiation from the reactor will be minimized in the same way that light from a flashlight on your face is minimized the further you walk away from it. In this way only minimal shielding would be required. The truss-like structure would hold up to the forces even if it was a weak constuction since the thrust from the rocket will be small.

Re:Radiation

[Anonymous Coward]

Lead is actually only a small part of the shielding used in the Nuclear Navy. The lead is good at moderating (shielding) gamma and beta (electrons) particles but the real threat are the escaping neutrons. Since the neutrons have such a high energy (high mass, high speed) they rip through lead fairly easily.

Therefore, the Navy uses a water shield around the reactor vessel to slow down (moderate) the neutrons. Since a neutron is about the same mass as a proton, the water (H20, where H is a proton) provides the best transfer of energy in elastic collisions. This is also why neutrons are one of the worst types of radiation for humans. (Alpha's are really bad but easily shielded.)

The result is that the water heats up.

They also use borated polycarbonate but that's for viewing windows and such.

Re:Radiation

[doubleyou]

Would the penatly be less for a fission rocket than it would be for a chemical rocket? I'm assuming that nuclear over chemical gets you more bang for your buck - more thrust with less fuel.

Re:Radiation

[Anonymous Coward]

True enough, but Jupiter has an enormous electro-magnetic field that does a good job of sucking in a lot of solar wind and cosmic radiation.

Once you get past its wake, all bets are off.

Re:Radiation

[Anonymous Coward]

Do a quick Google search on cosmic radiation, solar wind, or Jupiter's Magnetosphere.

Re:Radiation

[Anonymous Coward]

How does Jupiter's magnetosphere help when it's on the opposite side of the sun? I don't think Earth's and Jupiter's orbits are synchronized...

Re:Radiation

[Anonymous Coward]

Ya, I got it wrong.

Radiation is actually more focussed in its magnetic field. Thanks for the heads up.

On a Side note,
Check this out

Scroll down to the part about Radiation. There's a reason Astronauts only have a career life of 3-5 years. Cosmic Radiation. But we've got Navy Nukes riding subs for much longer periods of time.

Now, who's still worried about the reactor?

Re:Radiation

[Squalish]

The solution to this whole thing is water. In Red Mars, for example, a layer of water was used to protect the crew from solar datiation storms. The entire crew would crowd into a small chamber with a water reservior between them and the sun. The water is needed anyway for human consumption, and it does not get holes in it like metal does(you use a hole-filling rubber liner or something like people use in puncture-proof tires)

Re:Radiation

[AndroidCat]

Probably the same way we keep the reactor in a nuclear submarine from irradiating the crew?

Granted the shielding is heavy. Using a Discovery configuration with the engines at the other end of the ship from the crew quarters would help.

Energy needs, not exploration for its own sake

[fetta]

What sets this apart from most arguments for space exploration (at least in the popular media) is that he argues based on a need (energy) rather than talking about exploration and science for its own sake.

that's nice

[Syre]

Nice to see an old-timer get a little coverage on /., but he really covers no new ground in that short article.

The major objections then, as now, are:

- What happens if fission powered rockets crash? Instant nuclear disaster, unless the containment vessel holds (and it might, but the public will not be convinced it would).

- Other countries fears that fission powererd rockets are actually orbiting nuclear weapons, able to be dropped on them at will. And again, even if they weren't bombs, orbiting fission rockets would be nuclear weapons: all you have to do is build the containment vessel so it can be blown apart on impact via conventional explosives, leaving a cloud of contamination.

I don't predict these space nukes are coming any time soon. Better to invest in laser propultion and linear magnetic launchers.

Re:that's nice

[Stigmata669]

Other countries fears that fission powererd rockets are actually orbiting nuclear weapons, able to be dropped on them at will. And again, even if they weren't bombs, orbiting fission rockets would be nuclear weapons: all you have to do is build the containment vessel so it can be blown apart on impact via conventional explosives, leaving a cloud of contamination.

Why on earth would somebody use fission powered rockets for low orbit transit? The mass and $$$ savings are only worth the hassle on long distance space travel. The focus of the article was on sending missions across the solarsystem, not to the international spacestation.

Re:that's nice

[mcknation]

"Nice to see an old-timer get a little coverage on /., but he really covers no new ground in that short article. "

This guy's brother tought history in my high school. He is also the football coach and an avid weightlifter. He is far from what I would call an old guy. For your sake I hope he dosen't read slashdot! Coach Hickam wow that brings back memories.

Re:that's nice

[dillon_rinker]

Better to invest in laser propultion and linear magnetic launchers.
Lasers will be great for getting to Mars? Have you never heard of dispersion? As for magnetic launchers, did you not get the writer's point, that the goal is to accelerate all the way there?

Multiple spacecraft containing dangerously radioactive elements have already been launched. Danger exists, I don't deny it, but I'd suggest that those dangers can be overcome.

Re:that's nice

[zerocool^]

Better to invest in laser propultion and linear magnetic launchers.

Or time machines =) Now, if we could just get the power equivilant of a supernova into something the size of... say... a VW bug...

~z

Re:that's nice

[PM4RK5]

Maybe you could design it such that the launch apparatus is like those used today, but breaks off after exiting the atmosphere, where nuclear propulsion commences. (IE, you release no neutrons in to the reactor until the craft is a specified number of miles outside our atmosphere).

Even if it is practical, here's a comforting thought if you were an astronaut:
"Yay! We're going to Mars! ... And we're propelling ourselves using the worlds largest (hopefully controlled/directed) nuclear bomb!"

Re:that's nice

[falser]

What happens if fission powered rockets crash? Instant nuclear disaster, unless the containment vessel holds (and it might, but the public will not be convinced it would).

That's why they'd probably shuttle the rocket parts separately, particularly the nuclear core. Just as a nuclear missle is a dud without it's warhread, a nuclear rocket would not very dangerous without it's fuel.

Re:that's nice

[leucadiadude]

The focus of the article was elimination of chemical rockets and use of nuclear heated helium gas rockets for all launches, low earth orbit and up.

All launches would benefit from a thrust to weight ratio perspective. He did mention that if Hydrogen gas were used there would be some radioactive fallout from the gas. I imagine that would be from neutron reactions with the Hydrogen breeding tritium and deuterium as the Hydrogen is blased out of the reactor. Use of Helium instead would be less efficient but not result in any appreciable nuetron activation.

Re:that's nice

[leucadiadude]

"Maybe you could design it such that the launch apparatus is like those used today, but breaks off after exiting the atmosphere, where nuclear propulsion commences. (IE, you release no neutrons in to the reactor until the craft is a specified number of miles outside our atmosphere)."

The whole point is to ELIMINATE chemical rockets and go to fission rockets. The vast majority of the work is done getting to low earth orbit. Thats where it makes the most sense to use a much higher thrust to weight engine.

Re:that's nice

[ryanwright]

"Yay! We're going to Mars! ... And we're propelling ourselves using the worlds largest (hopefully controlled/directed) nuclear bomb!"

And built by the lowest bidder!

(What is this 11 seconds from the time you hit reply until the time you can submit crap? I thought Slashdot was designed for geeks who can type.)

Re:that's nice

[Anonymous Coward]

- Other countries fears that fission powererd rockets are actually orbiting nuclear weapons, able to be dropped on them at will.

The design of a reactor is very different from the design of a bomb. Such fears are about as rational as the fear that the reactor is part of a pentagram used to summon the Devil.

And again, even if they weren't bombs, orbiting fission rockets would be nuclear weapons: all you have to do is build the containment vessel so it can be blown apart on impact via conventional explosives, leaving a cloud of contamination.

At first glance that sounds more rational, but the Devil is in the details. There are easier ways to deliver such a payload.

Well, bring'em up dammit!

[Kwelstr]

I mean it, I wanna go to Mars and I was born too early! Let's get with the program people.

Re:Well, bring'em up dammit!

[doooras]

forget mars... i wanna go to Ferenginar... all the women are required to be naked. they're ugly, yeah... but they're naked!

Re:Well, bring'em up dammit!

[marcsiry]

News flash: Women here can be naked, too, if you do stuff like listen to what they say. Or at least pretend to, with an understanding look on your face, while you visualize them being naked.

Try it sometime :-)

Re:Well, bring'em up dammit!

[Jucius Maximus]

"News flash: Women here can be naked, too, if you do stuff like listen to what they say. Or at least pretend to, with an understanding look on your face, while you visualize them being naked."

MOD PARENT UP AS TROLL!!

Yes, you heard me. That was not a typo.

Re:Well, bring'em up dammit!

[Russ Steffen]

Women here can be naked, too, if you do stuff like listen to what they say. Or at least pretend to ...

You should start paying attention when they get those important questions... like "Who are you?" and "What do you want?" and the ever popular "How did you get in here?"

Re:Well, bring'em up dammit!

[Vulture_]

One problem: the men are also required to kill you and sell your organs if it turns out to be profitable.

Re:Well, bring'em up dammit!

[ryanwright]

if you do stuff like listen to what they say

I don't know, man... that sounds like a lot of work! [Kudos to Stifler]

Fission? He's GOT to be kidding!

[meckardt]

The reactor shielding required for a manned spacecraft is pretty large. There isn't any particular mass savings through using a nuclear power source... most of the mass for a deep space mission is reaction mass, and the specific impulse developed by a nuclear rocket is only about 2 times that of a chemical rocket... reaction mass savings ends up being on the order of 75%, but this is offset by the increased payload/structural mass.

Now, if someone could finally get fusion rockets to work, I think we could finally go someplace. But I am skeptical about using fission for manned missions.

NASA and responsiblity

[crystalplague]

NASA can't even keep all of their measurements in SI, and we're going to let them accelerate nuclear reactors to 17,500+mph?!?! what happens when the self destruct code has to be issued because some retard messed up the entire launch because he read a comma as a decimal: nuclear fallout? yes, nuclear fission powered craft are one of the only ways to get to where we want to go, but there are other options such as ion propulsion and some other innovative ideas floating around. also, the weight of the shielding around a nuclear reactor would make the craft horribly inefficient because it would be using all of the energy just to overcome gravity, rather than accelerating to never before seen speeds.

Re:Fission? He's GOT to be kidding!

[Anonymous Coward]

What, you a rocket scientist or something, biotch?

For sure!

[sfrenchie]

I agree 100%, someone should tell Mr. Burns to rethink his policies...Homer knows everything about n-u-c-u-lar rockets!

Re:For sure!

[Lakitu]

C'mon frenchie, it doesn't take a foilage expert to spell nuculear

Maybe...

[Anonymous Coward]

It's because all it takes is one crash and you've eliminated south florida. I know the beaches right next to the kennedy space center are real nice. Imagine having to wait 100k years before returning.

To sum up: The risk isn't worth the reward.

Besides haven't you seen Total Recall? All we need to do is get Arnold to push the button to make the planet habitable! lol...
I'll be back.

Re:Maybe...

[Aglassis]

Thats only assuming that you use the nuclear rocket part to take off. This is unlikely. A more likely case is it will be lifted by manual methods, piece by piece, assembled in orbit and then operated a safe distance from the earth. Even if these parts explode in takeoff it will not have any real radioactivity risk assuming that it uses normal fuel (ie uranium, not plutonium) since the half-life of U-235 is almost a billion years and U-238 is billions of years (longer half-life means less radioactive and billions of years means very, very small radioactivity). In newly built nuclear power plants you can walk around near the reactor without any radiation risk due to this fact. Of course once you start up, it has radioactive daughters and transuranics that make it radioactive.

Re:Maybe...

[Mishra2002]

That is a very uninformed assumption. First of the trajectory of all launches is such that if anything bad ever did occur it would happen ver the ocean. Which is why no bits of challenger landed on people's houses. Second The nuclear power source in many of these designs is not very large your only talking a few Kg's of nuclear material, and That's a lot. Typically i's more like grams. Nuclear energy sources use the natural heat of the isotope, not the actual fision process, this requires much less material. Do the calculation, how much U-238 do you need so it's still around 10 years from now, not much.

-Mishra

Re:Maybe...

[boskone]

Or even Thorium, which is as common in the earth's crust as lead. lots cheaper than U and Pu

Re:Maybe...

[kavau]

It is true that there is no great risk involved in being close to an Uranium source, since the radiation level is very low. The danger lies in the risk of contaminating the environment with radioactive materials. Imagine something like the Challenger disaster happening to a spacecraft transporting nuclear fuel: the Uranium would be spread over vast areas of inhabited land, getting into the soil, into the crops, being eaten by cattle, and finally end up on our dinner plates. And Uranium will affect your health very badly if it is in your system, not to speak of Plutonium. Not an immediate effect, but probably you'd die of cancer some decades later. There is an immense risk involved in shipping any larger amount of radioactive material into space. Sooner or later the spaceship would blow up, since it is impossible to construct anything 100% safe. The effects on our environment and health would be severe. That's why we have to be very careful with projects like that.

Re:Maybe...

[hey!]

IIRC the greatest health threat that has happened in past nuclear detonations or accidents like Chernobyl are fission by-products like Iodine-131. I don't believe U bioaccumulates, so it's probably not as much of a concern except for very high direct exposure. I am not a chemist (or even a real engineer), but it seems to me that with fresh Uranium fuel accidentally released into the environment from something like an ceramic fuel pellet, either the pellet is intact in which case the by-products aren't being released into the environement, or the pellet is destroyed in which case they are being produced at a very slow rate (given by the long,long half life of the fuel isotopes).

Personally, I'd be more concerned with mine and mill tailings from Uranium production, which contain the full range of decay products in large quantites, than the release of freshly refined fuel.

On one hand, I think it is naive to think you can have a program which launches radioactive fuel into orbit on a regular basis without some release of radioactive materials into the environment. On the other hand, while I'm generally supportive of enviornmental positions, arguing a zero tolerance for release of radioactivity into the environment is to vague a position for me to support. What kind of radioactivity? What form will it take? At what point in production or use will it be released?

Re:Maybe...

[Xaoswolf]

We have nuculear powered warships at sea don't we? At least nobody will be trying to shoot down the rockets.

Get Yer Poster Boy Decal Now

[Anonymous Coward]

I think Slim Pickens riding the nuke in Dr. Strangelove should become the Poster Boy Decal for the nuclear-powered rocket projects. That one scene said all there is to say about the cowboy in space.

Anagrams (slightly OT)

[dhovis]

I read the book and I saw the movie. This is a case where the book is much better, though both are somewhat fictionallized.

Incidently, "October Sky" is an anagram for "Rocket Boys".

Re:Anagrams (slightly OT)

[Phosphor3k]

Other anagrams for October Sky:

Bye Sock Rot
Be Coy Stork
Bot Rock Yes
Yo Bots Reck

Re:Anagrams (slightly OT)

[wedg]

Wasn't it a guy's memoirs? Can memoirs be fictionalized?

Re:Anagrams (slightly OT)

[Anonymous Coward]

No, it is illegal to fictionalize memoirs. Punishable by 200 years hard labour.

Re:Anagrams (slightly OT)

[Anonymous Coward]

And "Slashdot" is an anagram for "lads host". Anagrams never lie.

Re:Anagrams (slightly OT)

[dhovis]

The book is one of those "based on true events" types.

AFAIK, the book is mostly the story of his life, with some embellishment here and there and presumably some stuff left out to make a better story. The book is upfront about this, and some of the names were changed so as not to embarrass anyone who might come out in a bad light.

One scene in the book that is made up (as I recall) was the one where he saw Sputnik passing over West Virginia. Apparantly it never happened, I think it was cloudy that day, even though it was the catalyst (in the book) for him wanting to build rockets. That scene also gave the movie its title, looking up at the "October Sky" and seeing Sputnik.

Re:Anagrams (slightly OT)

[lfourrier]

This is a case where the book is much better,

Why consider the rule as if it was the exception?

.

I kinda agree, and kinda don't.

[WolfWithoutAClause]

Whilst nuclear is one option to get us out there, particularly to the furthest planets, I don't agree that this is necessarily the way to go.

Putting the supposed issues of launching nuclear rockets to one side, all of the issues we know of will be solved by using the existing resources of space, rather than trying to launch every little thing from the earth. Right now we are doing the space equivalent of driving from East to West coast America, whilst carrying all our gas with us for the whole trip. Ever heard of gas stations?

NEOs and the moon have plenty of fuel for us to use, and if you refuel in space, the maximum distances we can go are enormous.

The other issues also become non issues. Radiation? A few tonnes of shielding isn't a problem if you have enough fuel. Gravity? Spin your spacecraft on a tether, and simulated gravity is plenty good enough [the only reason that this isn't proposed right now is mass constraints, also they want zero-g in the ISS for example]. Again, use non terrestial sources for materials, and most issues are gone.

Nuclear is an entirely safe and reasonable approach. But it's not a necessary one. And politically there are huge issues; for what are mostly dumb reasons. But we have to deal with dumb reasons, held by misguided people in life.

Try to move beyond your provincial mindset buddy

[Anonymous Coward]

And when the vulcans see our depleted uranium trail on the way back from their survey mission they'll be so impressed! :)

Sure fission would get us where we need to go
but we'd end up polluting even more of our
surroundings.

I don't think we should be aiming for Mars when
we can't even travel to th moon in under a day
and when we still have people who think with
such a provincial mindset.

Until then I'll just keep clearing the bushes in
my backyard with that suplus C4 my buddy gave me.

He has a point

[prizzznecious]

Beneficent advances in nuclear fission are made all the time. Check this article out.

I don't wanna go to Mars!

[kamapuaa]

This article doesn't really cover any new ground, and is lacking any real details...it's more of a generic endorsement from a celebrity scientist than anything.

I think the idea of going to Mars is wrong headed. I don't think an exploration of Mars will lead to great new developments for humanity. I don't think the idea of colonizing Mars is practical, and if it was, it certainly won't help humans on the Earth. I realize Apollo R&D helped lead the push towards creation of ICs, but I think any R&D budget would be better spent elsewhere...

Specifically, I hear about the idea of terraforming, which even with the most advanced technologies would take a ridiculous amount of time, even if it's possible to replicate the complex necessities of Earth conditions on a planet wide scale. Or the idea of releaving overpopulation through colonization, which is so silly it can be freely ignored.

Mr. Hickam seems to assume everybody shares the dream of having people live in a big plastic bubble far away...and the enormous cost, as well as the very real threat of putting nuclear reactors in ships that tend to blow up in the atmosphere, are insignificant. It's an odd viewpoint that he doesn't bother to justify. Will it make people's lives better? Should it just be done because it can? Manifest Destiny in space is so sci-fi.

Re:I don't wanna go to Mars!

[Anonymous Coward]

History shows us that fools like you do nothing to improve the human condition. Spineless and weak, your ilk would have us all still hiding in trees because the "ground" was just too far away and wasn't worth the effort. There is nothing wrong with the concept of Manifest Destiny in space.

Now return to your tree you shortsighted pussy!

Re:I don't wanna go to Mars!

[doubleyou]

"I don't think the idea of colonizing Mars is practical..."

"...but I think any R&D budget would be better spent elsewhere..."

I agree with you on both counts, but only if the qualifier "...for now" is tacked-onto the end of both of those statements. I think it's too early for us to be going to Mars. We need to establish a presence on the Moon first, so that we can make our mistakes closer to home. If something goes wrong between here and Mars, those astronauts will be f---ed.

"Manifest Destiny in space is so sci-fi."

You say that as though sci-fi is something that's bad, or out-of-style. Don't forget how much sci-fi has come to pass in our modern world. To dismiss it as fantastical is pretty short-sighted. I for one am inspired by lots of the sci-fi I read, and truly believe that much of it will come true one day.

Re:I don't wanna go to Mars!

[coding_ape]

perhaps you are forgetting the (quite reasonable) possibility of finding life on mars.

The day we find extra-terrestrial life, whatever its form, is without question one of if not the most significant days in human history. That seems like reason enough to me.

Re:I don't wanna go to Mars!

[BillShatner]

Relieving overpopulation through colonization is a bit like curing obesity by buying bigger pants.

Re:I don't wanna go to Mars!

[geo_flux]

If you want a reason for going beyond Earth how about the increased chances for the survival of the human race. Remember the old proverb about keeping all of ones eggs in one basket. That is what we are doing now with the human race, one ELE asteroid and we're done for. Settling, the moon, the asteroids, Mars, etc will ensure that the human race will survive such a catastrophe.

Re:I don't wanna go to Mars!

[TRACK-YOUR-POSITION]

I think of it more as buying a bigger wallet for your new job.

Meaning the thing you are trying to contain is a good thing, that we'd like to have more of if only we had space for it.

Re:I don't wanna go to Mars!

[cb0y]

So you think the $350 BILLION USA spends on DEFENCE is beneficial to man kind? add another $800 BILLION on medical care for plebs, and you will see that a small $50B amount is nothing in comparison to the FEDS $3000 BILLION anual budget. Get a grip dude, space is cheap compared to asprin. More is spent on womens cosmetics ($1500 BILLION yearly)

Re:I don't wanna go to Mars!

[digitalgiblet]

Too bad!

Pack your bags, buddy, we're shipping you out next week!

We're going to colonize Mars whether you "volunteer" to go or we have to round you up and stick you on a rocket.

And don't be whining about the conditions, either. There's some air on Mars! Granted not as much as you're used to with your mollycoddled earth upbringing, but some of the stronger "colonists" will survive and reproduce. You might be one of them!

One day, when the hyper-robust Martian colonists have had just about enough, they will return to earth and solve the over-population problem once and for all! It's a win-win situation.

Re:I don't wanna go to Mars!

[Mr. Foogle]

You don't "wanna" go to Mars?

Fine. You stay here. Have a nice life, we'll send you a postcard.

Re:I don't wanna go to Mars!

[jonerik]

I think the idea of going to Mars is wrong headed. I don't think an exploration of Mars will lead to great new developments for humanity. I don't think the idea of colonizing Mars is practical, and if it was, it certainly won't help humans on the Earth.

bIHnuch! You would dare dishonor your name and Qo'noS through your cowardice! You are worse than a mewing Qa'Hom with water for blood! Do you not desire glory for your house?!

Re:I don't wanna go to Mars!

[ajdecon]

Then I hope you have a very happy, boring life in which every decision you make is the sensible one, no dreams exist, and nothing unexpected *ever* happens.

It may not be practical currently, and the motivation so many mention (relieving overpopulation) *is* unrealistic. But economic reasons aren't everything, y'know. Scientific benefits, contributions to knowledge of working in space in general, all sorts of benefits that are not currently economical--and, IMHO, *never need be*. And anyway...

Didn't you ever, in all your life, want to go somewhere just to *see*?

Part of Kennedy's Dream

[Aglassis]

This was one of Kennedy's four goals during his Special Message to Congress on Urgent National Needs (a.k.a. go to the moon speech). He said that it gives "promise of some day providing a means for even more exciting and ambitious exploration of space, perhaps beyond the moon, perhaps to the very end of the solar system itself".

The nuclear rocket is probably the best choice in large distance exploration that we have right now. Solar power becomes useless pretty much past the Earth and no other power source can pack the mass to power ratio that nuclear power can. If we want to go big, we have no choice but to use a nuclear rocket or take a long, long time. The weight issue in rockets is a big deal, so alternate propellants are out since they will take up to much weight for the same power.

For close distance exploration (i.e. the moon) I don't really see a nuclear rocket taking any part. While obviously it could achieve its goal, its a little overkill for the purpose (and considering the fact that if it were a direct exhuast type it would have a plume of activated radioactive materials, assuming it uses water as a propellant, it probably wouldn't be that popular).

I hope this happens, and I've been hoping for a long time. Its our only real chance to get off the earth permanently at the present time.

Re:Part of Kennedy's Dream

[andymoe]

What about the nifty ion thrusters under development?

Re:Part of Kennedy's Dream

[Aglassis]

Everythings got to have a power source. If you use an ion engine you currently have to use solar power, a battery, or a fuel cell to get it to run. In deep space the solar array would produce no power, the battery would discharge and the fuel cell would burn all its fuel. Of course you could use a nuclear source (such as the plutonium sources that Cassini uses), but that is very low power and wouldn't get you far. If you used a nuclear reactor in the conventional sense to make electricity you could power it, but you'd have to find some method to get rid of the heat needed to condense the steam after it operates the turbine. Since space doesn't allow conductive or convective heat transfer, the only way to transfer heat is through radiative heat transfer. While this technology does exist (its on the ISS), its not particularly powerful and you might end up covering the entire ship with your radiator. I think that at the current time it would be more efficient to use direct thrust than to try to use some sort of ion engine due to the disadvantages of trying to find a method of heat transfer (the added weight of the radiator would probably offset the added efficiency of the ion engine) and since no heat transfer process is ever 100% efficient. You are getting most of your energy in the direct type but you would get less energy from the reactor powers turbine type due to the inefficiencies in any turbine, and the requirement to condense steam; therefore, a good portion of your energy is radiated away.

Slow down sonny

[Anonymous Coward]

I'm not sure I'd want to pilot something that
can't even protect me from the sun's radiation
let alone radiation coming from 100 meters
behind me.

I've seen a lot of comments stating that Fission
is a safe and viable technology. Until the day
passes that there hasn't been a nuclear leak or
Chernobyl for at least 100 years I wouldn't say
that's the case. Clearly the experts really aren't.

Space will still be there 100 years from now when
we either get it right or we figure new and better
ways to get there.

Re:Slow down sonny

[Anonymous Coward]

Yeah, but will we be?

Re:Slow down sonny

[Mahonrimoriancumer]

Come on!!! Every nuclear power accident has been because the HUMAN operators refused to stay within the safety limits. This goes for Chernobyl, Three Mile Island, etc. Please name incident that was caused by machine failure and not by human stupidity.

Re:Fission? He's GOT to be kidding!

[Anonymous Coward]

That's why you build fsck-off big space ships, in orbital space factories. We might be able to go to the moon in an oversize metal toilet roll but if I'm going to Mars, I want something a little bit bigger. A ship to take stuff that far will undoubtedly be large anyway, so it's probably gonna need a big engine. Remember that 1/3rd of a car is engine regardless of how far you travel.

Anyway, a couple of questions:

Why do we not have a moonbase? Surely it's easier to stick something on a ball of rock than it is keep it propped up over the planet?
How come after 33 years, all we have to show is a bit of scaffolding with some solar panels attached?

It sucks! And it sucks because since the 1960s, the American establishment has been obsessed with warfare and the economy... and they're the only nation big enought to pull anything like this off.

So when all get pancaked by a global killer in 20xx, we'll know which country to blame...

Basic physics

[Anonymous Coward]

"To go to Mars or back to the moon with slow, low-powered chemical rocket systems is asking for trouble. The best a chemical rocket can do is get up to speed (burning up all its propellant in the process) and then drift to its destination, like a car coasting down the highway with its engine off. What's needed are space drives that will provide a constant velocity."

Anyone who has completed highschool physics should find something wrong with this statement immediatly. Since there is negligable friction in space any engine can provide a constant velocity, including fossil fuel based engines. What's actually needed are space drives that will provide a constant acceleration for long periods of time.

Sheesh, and this guy is a NASA astronaut. It really makes you wonder sometimes...

Re:Basic physics

[andymoe]

hmm well if they want constant acceleration, they can just go in circles.

Ok bye now

Re:Basic physics

[doubleyou]

Don't forget about the pull of the Sun's gravity. If an object were to "drift" across the solar system, it would settle into some sort of orbit (even if that's a decaying one). To have an effective constant velocity, one would have to counteract the gravitational pull the Sun exerts.

Usually, if you're going to go from one planet to another (within the solar system) you would want to apply an initial acceleration such that you put yourself in an orbit around the sun which is tangential with the orbits of your source and destination. (And it would have to be tangential at the right time too, so you and the planet meet at the same time.) But the acceleration only happens for a short while at the beginning, and the deceleration would happen at the end of course. But the rest of the journey would be drifting once the orbit was established (not counting minor course corrections along the way). This way you're using the Sun's gravity to your advantage, and saving fuel (but the journey takes a long time).

So what do they plan on doing with nuclear rockets? Do they plan to cut right across the orbits (thus saving lots of time)?

Re:Basic physics

[pdp11e]

>Don't forget about the pull of the Sun's gravity

If we apply Newton's law of gravitation:
Strength of Sun's gravitational field = G*M/r^2 = 0.0059 m/s^2
(G = Newtonian gravity constant; M = Solar mass ; r = Sun - Earth distance)

That is only 0.006g. Since we are traveling from Sun towards Mars, field strength is only getting lower.
Now let's do another exercise:
Earth - Mars distance varies between 55 and 350 million kilometers. Let's assume that space vehicle has to cover 100 million km. For the first part of the voyage it accelerates with constant acceleration:
a=0.01 g (+ 0.006 g to compensate for the Sun) and then spends the rest of the journey braking at -a. If you do the math (hint: s=at^2/2). it turns out that it takes 73 days to get to the Mars. It would take hundreds if not thousands of g at the liftoff and landing to do it conventional way (I am not volunteering for that mission!).
Note that we are talking about 0.01 g. That is far less acceleration in comparison to say: eighteen-wheeler, loaded with lead bricks, powered by the Yugo's engine.
Disclaimer: I haven't done the math if it is feasible to achieve 0.01 g. It is 1 AM and I don't feel up to it. Any colleagues willing to solve Meshchersky equation?

Perfectly Serious

[jeff.paulsen]

You're missing a couple of critical points:

1. First, your reaction mass is your reactor shielding. There's a whole lot of water or liquid CO2 between the pile and the crew.
2. Second, the craft only has to carry reaction mass for one way. You get to Mars, you turn on your compressor (powered by your atomic pile), and pump the local atmosphere into your tanks. This is a huge advantage. CO2 provides a lower specific impulse than, say liquid H2, but it's plenty to get back to Earth, or to push on to Titan.

In short, there are huge advantages to a nuclear rocket over a chemical rocket. Check out NERVA and NIMF, the two best treatments of the subject.

Re:Perfectly Serious

[CoopersPale]

Your reaction mass is your sheilding?

Then what happens when you run out of reaction mass? You run out of sheilding....

Re:Perfectly Serious

[Zathrus]

You also run out of reason to have the reactor actively fusing/fissioning. And while there's still radioactivity from the core, the real worry is the short half-life byproducts of the process. Shut down your reactor and those go away reasonably quick.

Of course, if all of your reaction mass/shielding is gone, you're probably sterile and/or dead anyway because of the radiation you'll soak up from the sun (depending on term of exposure and how active the sun is being, obviously).

Re:Perfectly Serious

[Cally]

> In short, there are huge advantages to a nuclear
> rocket over a chemical rocket.

Yeah, and one fsckin massive DISadvantage: it'll never happen, buddy, and you're dreaming if you think different. (for a given value of "never" meaning "not in the lifetime of anyone alive today.")

Re:Fission? He's GOT to be kidding!

[Anonymous Coward]

"Now, if someone could finally get fusion rockets to work"

Well, first lets find someone who'll get fusion to work period, let alone fusion rockets...

A clean energy source?

[robmered]

Nuclear power is not a clean source of energy as alleged in this article. The mining, production and disposal of nuclear material makes it one of the more dangerous forms of energy production. The material used in reactors remains dangerous (ie. life threatening) for hundreds of thousands of years. How can anyone (apart from dubbya) define this as clean? Sure there are no smoke stacks, but come on!

As a uranium producing country, Australia has seen a number of 'mishaps' in relation to uranium mines. Admittedly, most of them have been relatively minor, but they demonstrate that no human activity is 100% failsafe, and the potential for massive disaster is huge when compared to other forms of energy production, fossil fuels included. Of course, this does not diminish the need to find alternatives to fossil fuel sources, they are dirty and finite (ie. unsustainable). Nuclear energy is not an appropriate response, though.

Also, beyond the production and disposal of nuclear material, what happens when something goes wrong with the rocket itself? Could you imagine a nuclear version of the Challenger disaster?

I'm as much of a technocratic utopian as any other /. reader, but even I realise that the use of technology, and its impact on society, is more important than any geek factor.

Re:A clean energy source?

[fea]

wrong. Imagine all the waste of all nuclear plants in the US combined over their lifetimes. It will fit in a football field stacked up a few stories high. Now imagine all the waste of the same power source (equivalent) of coal-fired power plants. Where is the waste? Everywhere. With Nukes, you know where the waste is. The most environmentally friendly power source is nuclear. Now imagine all the windmills it will take to equal one Nuke plant. I am looking at 3 of them now from my back yard at TVA's Buffalo Mountain project. It will take 3 thousand of them which will leave absolutely no mountain, trees, or anything else for that matter. Get real man and get out of your closed world.

Re:A clean energy source?

[BigBir3d]

ever heard of a coal mine? the rock that they tunnel through is like a shale. not very sound, structurally. dangerous.

i think petroleum is combustible. dangerous.

most modern mining is automated. quicker results. less dangerous.

also, don't think of launching rockets from the earth's surface, think of launching a long distance space vehicle/rocket from high earth orbit. the necessary elements could be transported to the orbiting station via reliable un-manned rockets in the safest way(s) contrivable. it would also provide a service for the current nasa/russian/whoeverisnext shuttles later on; ferrying non-hazardous goods and people back and forth to this spaceport.

as for what to do with 'used' nuclear rockets? i think superman had a good idea; fling them into the nearest star.

Re:A clean energy source?

[Anonymous Coward]

Nuclear power is not a clean source of energy as alleged in this article.

Yes it is. It is the cleanest source of practical energy currently known to man. Even cleaner than solar and wind, when the construction wastes are included (for example, all the chemical processes used in the construction of P-N photocells).

The mining, production and disposal of nuclear material makes it one of the more dangerous forms of energy production

Ha! The only way this argument could even begin to be valid is if you were only counting radioactive wastes. And FWIW, a coal-burning electricity plant puts out more radioactives into the environment in a single hour of operation than a nuke plant does in its entire operating lifetime.

Re:A clean energy source?

[mcelrath]

Nuclear power is not a clean source of energy as alleged in this article. The mining, production and disposal of nuclear material makes it one of the more dangerous forms of energy production.

How many people have died due to gasoline fires? Oil well mishaps? The fact that people can be harmed by a technology is not a good reason to not pursue the technology. As with everything, we must minimize the risk and get on with life. As you say, no human activity is 100% failsafe. We are now, and will continue to produce nuclear material. The amount of nuclear material used in rockets will be very small compared to the amount used in power plants worldwide.

Also, beyond the production and disposal of nuclear material, what happens when something goes wrong with the rocket itself? Could you imagine a nuclear version of the Challenger disaster?

A fundamental design requirement of any nuclear reactor is that it must survive re-entry intact. Nuclear fallout is simply unacceptable. Tests can be performed. Take the reaction vessel, fill it with a volatile liquid, and drop it out the ISS airlock. If none of the liquid escapes and the vessel is recovered intact, then it's good enough to house nuclear material.

Again, this is simply a design requirement, and not a good argument to stop all development of nuclear rockets.

-- Bob

Re:A clean energy source?

[cb0y]

If detonating a nuke is so easy, then why is it so damn hard for anyone to make a nuke? If you at home had 10kg of plutonium and packed it with 50 dynamite sticks around it for force. It wouldnt go off like a nuke.

Re:A clean energy source?

[Anonymous Coward]

Nuclear power is not a clean source of energy as alleged in this article

Yes, it is. It has FAR less environmental impact than coal or oil. Burning coal releases MORE radiation than a nuclear power plant for the same energy production. Look it up.

no human activity is 100% failsafe, and the potential for massive disaster is huge

What about this scenario? A new techology is developed which is convenient and fun to use. The only drawback is that every 5 years something goes wrong and a city the size of San Francisco is wiped off the face of the Earth. Should we use this technology?

Surprise: We already are. It's called the automobile.

Re:A clean energy source?

[MtViewGuy]

There's a very dirty (quite literally) secret about coal burning few people talk about: the fact it releases a substantial amount of radioactive material into the air. People forget that trace amounts of radioactive elements exist in many forms of coal.

Re:A clean energy source?

[ahodgson]

Fossil fuel production kills people every day. Fossil fuel waste products kill thousands of people every day. They are most likely changing the entire climate of the earth, which may kill millions of people in the near future.

Nuclear power, used in the US, Japan, France, Canada, etc., has killed maybe a couple hundred people total, ever. No, I am not counting Chernobyl. I wouldn't want the moronic 12-year old bully down the block running a nuclear power plant, and the people running the Soviet Union cared even less about my welfare. But done correctly, it's pretty safe. Not cheap, but safe. And it's only expensive because fossil fuel is basically a giveaway - mother nature did all the hard work a long time ago. Sooner or later we will run that well dry.

Since these are the only 2 scaleable power sources we have available with current technology (as we've already exploited most of our hydro possibilities), I really fail to see why people consider nuclear unsafe.

Re:Fission? He's GOT to be kidding!

[martissimo]

His suggestion of the moon as a source of Helium-3 is pretty interesting though. Would sure think that trying to discover if we can use the moon as a source of the world's energy needs would be better research than the the money being spent on the International Space Station, although i so suppose that a space station would be necessary to really get to work on the moon easily as well.

lots of great reads about H3 on the net, would love to see a little more research on the stuff.

Re:Fission? He's GOT to be kidding!

[SWTP]

Basicaly the water tank will work but basically you stick the engine far in the back. Look at 2001 Discovery ship the engine is way in the back. Also with a pile generating juce it can also be used to create a field around the ship.

The real problem is not when you are out there but just getting up there when you want to for a cheep price.

An old statement goes like this:

When you get to orbit you are half way to everwhere.

Nerva + SEALAR

[Anonymous Coward]

Nothing wrong with nuclear propulsion. For the weak of stomach, you can launch in the middle of the Pacific, if there's a boo-boo, it drops in the ocean. Tough for the sharks, tough for the islanders, but they're used to it.
Oh yeah, SEALAR means Sea Launch and Recovery, from Bob Truax.

Re:Nerva + SEALAR

[robmered]

Right. Chernobyl style disaster, six miles up in the jet stream, and it's just the sharks who have to worry. Good one.

Re:Nerva + SEALAR

[Anonymous Coward]

Excuse me, Sir Dumbe Asse, but how would that have been different from launching from the ground? At least in the ocean, any incident that would would have been a disaster at ground level would have been mitigated.
And what's wrong with blowing up in the jet stream? Been there lately?

Re:Nerva + SEALAR

[praedor]

A nuclear rocket as all the proper designs are laid out CANNOT have a meltdown. You CANNOT have a Chernobyl-style accident with a nuclear rocket. We are not talking Orion either - that is a nuclear bomb rocket. A nuclear rocket is merely a nuclear core hot enough to vaporize whatever fuel you choose to pump through it. It could be water, producing high-pressure steam. It is NOT automatic that a nuclear core MUST be able to meltdown (ala Chernobyl). Nuclear power doesn't automatically mean "meltdown potential".

If there is a problem with a nuclear rocket launch, you don't need to blow it up. Actually you don't want to. You simply shutdown the engine and parachute it down for recovery and repair and try again. There is no volatile, explosive fuel to worry about (that is the only reason chemical rockets are destroyed if they have problems. Don't want a big, explosive bomb landing on anyone. It is even too dangerous to shut them down and parachute them down. They can still blow up. Not so with a nuclear rocket. They are SAFER than chemical rockets.

Re:Nerva + SEALAR

[robmered]

My point, if you care to think about it for a moment, is that the jet stream tends to carry airborne substances (like radiactive clouds) to places other than where they initiated. What goes up, tends to come down, so just because you launch at sea does not mean that a risk is not posed to some population of people somewhere else on earth.

Re:Nerva + SEALAR

[robmered]

Point taken. However, that assumes that all of these systems work. Unless you can guarantee that all of the safety systems will work all of the time, then you are still faced with the following equation: Risk = Probability(Something Going Wrong) * Cost(Something Going Wrong) With chemical rockets, the first part of the equation may be larger than for nuclear rockets. However, the last half of the equation is much larger for nuclear than for chemical.

Da Shuttle

[Latent Heat]

If it weren't for Da Shuttle, we could have had Moon bases by now. The Saturn V could take crews and payloads to the Moon -- Shuttle can barely make low-Earth orbit. Saturn launches probably run a billion dollars each, but each Shuttle launch runs a cool half billion, depending on who is doing your accounting. Besides, the Saturns were already designed while with the Shuttle they had to sink in several billion to get it going. Budgeting, say 3 billion a year, doing 3 launches a year to the Moon, by now you could have had over 30 years tons and tons of stuff delivered to the lunar surface. Instead, this same money was pissed away on the Shuttle and the stupid space station.

a constant velocity?

[QuantumG]

To go to Mars or back to the moon with slow, low-powered chemical rocket systems is asking for trouble. The best a chemical rocket can do is get up to speed (burning up all its propellant in the process) and then drift to its destination, like a car coasting down the highway with its engine off. What's needed are space drives that will provide a constant velocity.

Err, excuse me. Maybe I'm not Mr Rocket Scientist but isn't "providing a constant velocity" exactly what chemical rockets do? Maybe you mean provide a constant acceleration. Sigh. When you have to correct NASA officials maybe it's time to lose faith in space exploration.

Re:a constant velocity?

[Phosphor3k]

There are solar winds and Gravity produced by large masses(ie the sun, jupiter), that need to be resisted/overcome during planet to planet travel.

Not all highways are flat my friend.

Re:a constant velocity?

[CoopersPale]

And you would need acceleration (ie. the ability to speed up or slow down) to overcome these obstacles.... schoolboy physics.

Re:a constant velocity?

[Phosphor3k]

Its all relative jackass. You would need just enough thrust to correct for these forces to stay on course. You wouldn't be accelerating (relative to the solar system) at all. You would be moving with a constant velocity.

Re:a constant velocity?

[bellers]

Hey. That's DOCTOR Rocket Scientist to you, bub.

Good Luck

[BlackGriffen]

Nuclear is practically a dirty word. Just stick your head out the door and say it, and in 5 minutes you'll have at least 5 hippies protesting outside. They won't know what or exactly why they're protesting, but it has the word "nuclear" attached to it, so it must be bad.

It's the same way with health nuts and the word "chemicals" though they don't protest it, they just condemn it. Just walk up to someone in a health club, and ask him, "Do you know how many chemicals you have floating around in your body?" and watch him get a disgusted look on his face like you accused him of having herpes. Or ask some clerk at a health food store, "How many chemicals does this have in it?" and laugh at his ignorant @ss when he tries to claim there aren't any.

BlackGriffen

Re:Good Luck

[kawaichan]

One of the biggest problem with NASA is the lack of marketing department.

The government should have a marketing department, it shall be called Department of General Education.

Instead of calling "nuclear powered rockets", we should call it, Next Generation U235 Fission Based Rocket System.

Re:Good Luck

[Engdy]

My own personal filter is the pronunciation test. Does the hippie say "noo-cyoo-lar", or as it should be pronounced, "noo-klee-ar"? If he mispronounces it, I automatically assume he doesn't know what he's talking about and find myself another hippie.

Re:Good Luck

[Anonymous Coward]

Or just call it the Department of Propoganda like the Nazis did.

Re:Good Luck

[pclminion]

We have a hippie-type in my Alpine Environments class (I've been made fun of enough, no need no need). This guy is seriously f*cked in the head. He probably comes to class on acid or something. Anyway, we were discussing how solar radiation intensity (insolation) varies as a function of altitude, and the impacts on snow conditions, and this guy jumps up and yells out:

"You mean there's RADIATION COMING FROM THE SUN??!!?!?!?!"

Re:Fission? He's GOT to be kidding!

[Rothfuss]

Homer Hickman:

"During his long NASA career, Mr. Hickam worked in propulsion, spacecraft design, and crew training, and won many awards including the Astronaut Office's coveted Silver Snoopy award for his outstanding support of the astronaut corps, and a special commendation for overall excellence from the Director of the Marshall Space Flight Center. His specialties at NASA included training astronauts on science payloads, and extravehicular activities (EVA). He also trained astronaut crews for many Spacelab and Space Shuttle missions, including the Hubble Space Telescope deployment mission, the first two Hubble repair missions, Spacelab-J (the first Japanese astronauts), and the Solar Max repair mission. Prior to his retirement in 1998, Mr. Hickam was the Payload Training Manager for the International Space Station Program."

Mike Eckardt:

"Like many of you, I wanted to be an astronaut when I was young. It wasn't the glamor of a high profile, high risk job. It was the adventure. I lost that dream sometime during my teen years, when I realized that I wasn't enough of a Superman to join America's astronaut corps. But hope springs eternal. With the increasing availability of space flight in the 21st century, and the advent of a commercial tourist industry in space, I may yet manager to make my way into the high frontier."

Thanks for your input Mike. We'll get back to you.

-Rothfuss

Re:Fission? He's GOT to be kidding!

[NonSequor]

Take a look at this.

It works. Not well enough to be used for a power source since the costs would be so high. Eventually they should be able to get more energy out of it and reduce the cost to build the reactor.

Check your terms

[Preston Pfarner]

The best a chemical rocket can do is get up to speed (burning up all its propellant in the process) and then drift to its destination, like a car coasting down the highway with its engine off. What's needed are space drives that will provide a constant velocity.

So what's the difference between drifting and moving at a constant velocity? Spaceflight analysis really shouldn't be done by people who fail to distinguish between velocity and acceleration.

Re:Check your terms

[Phosphor3k]

The difference is overcoming things like gravitational fields of planets and the sun, solar winds, particles that get in your way and slow you down, ect ect. Drifitng will not cut it.

Re:Check your terms

[Dyolf Knip]

The thrust required to correct a well-planned interplanetary orbit could be accomplished by having an astronaut piss out the ship away from the direction they need to go.

Really, any halfway decent orbit would barely be affected by solar wind and dust particles. The overlapping gravity effects are terribly hard to figure out, but they can be done well in advance on any computer and accounted for fairly well. Note that most comets have very safe and regular orbits despite never correcting theirs.

Re:Check your terms

[Anonymous Coward]

Oh, I think he meant constant acceleration.

But don't forget you are fighting the sun's gravity, hence on a free trajectory to Mars, after launch and burn-out, you will be slowing down (apart from other forces such as solar wind).

Gee, depending on relative positions (eg. sun and moon), your rocket may even speed up first, and then slow down (all with no fuel expenditure).

Lets not get into Houghmann transfer trajectories.

You need a certain minimum energy to get to Mars (actually less than to the moon), constant acceleration speeds the time up at the cost of energy.

I think Hickham was thinking along those lines and got sloppy with the words (just as I have).

Oh my God, I'm so affraid!

[Erris]

- What happens if fission powered rockets crash? Instant nuclear disaster, unless the containment vessel holds (and it might, but the public will not be convinced it would).

Oh, you mean like Chernobyl? Not to make light of 100 or so deaths, but there are worse things in the world. It's hard to get worse than Chernobyl: Big core with high burn-up (that's lots of fision products from running), Zero containment, chemical explosions and fire at ground level.

Or perhaps you were thinking of all of the thousands of above ground nuclear bomb tests that the people have performed?

- Other countries fears that fission powererd rockets are actually orbiting nuclear weapons, able to be dropped on them at will. And again, even if they weren't bombs, orbiting fission rockets would be nuclear weapons: all you have to do is build the containment vessel so it can be blown apart on impact via conventional explosives, leaving a cloud of contamination.

Holy Armagedon, Batman! Do you think that this is a more practical means of nuking your friends than the tens of thousands of purpose built warheads lying around?! What shall we do?

I suggest we quit fooling around with bullshit fears and get some good use out of Nuclear technology. Projects Kiwi and NERVA were technical sucesses killed by ludite nonsense. We can go to Mars, we can exploit the solar system and we should do so. The sooner the beter, population expands geometricaly. We can use nukes to solve our problems peacefully, or we will use them the other way as we run out of exploitable resourses here. Chose your children's future.

Re:Oh my God, I'm so affraid!

[robmered]

Oh, you mean like Chernobyl? Not to make light of 100 or so deaths, but there are worse things in the world.

100 or so deaths at the time of the explosion. You are, of course, forgetting the disasterous impact the explosion had on farming across Western Europe, the thousands of birth defects, the thousands of people who now have cancer, the fact that no-one can live safely in the area for years and years. A potential Chernobyl sized-disaster not something worth worrying about? Good thinking, Sherlock.

As for your argument for exploiting the solar system, you leave a few things to be desired - like a cogent argument for example. Just because we can do something is no argument for in fact doing it. As for a geometric population explosion, not in the so called 'developed world', buddy. Birth rates are dropping to below the replacement rate.

Re:Oh my God, I'm so affraid!

[Dyolf Knip]

Just because we can do something is no argument for in fact doing it

Yes, good point. Let's all sit here on this one little godforsaken planet and hope that nothing comes along and does a number on it. There's really nothing to worry about. Aside from the natural possiblities like solar flares, asteroid impacts, ice ages, global warming induced flooding, and freak tectonic action, there's just the pesky manmade problems of nuclear wars, virulent diseases, and shoe manufacturing run amok. All of these could quite possibly wipe out our species, almost certainly our civilization, but there's really no need to hedge our bets by establishing Earth's progeny on other planets.

I realize that the odds of anything we can't handle coming along in the next few years is pretty slim to say the least, but I for one am not willing to bet the human race on it. Particularly when the potential rewards for moving out into space are so great.

Re:Oh my God, I'm so affraid!

[Ozx]

Yup, let's all live on Mars where it's lush, there exists eternal peace, and natural disasters are unheard of...

Re:Oh my God, I'm so affraid!

[Dyolf Knip]

It's not a question of finding a place where there are no dangers. It's about being in enough places so that the possibility of all of them being affected to a lethal degree all at once is essentialy nil. If something really bad happened to Earth, it'd be nice if there were colonies near or at self-sufficiency scattered around the solar system (and beyond?) that could build anew.

A line from "A Deepness in the Sky" by Vernor Vinge that stays with me is the one about Earth having been resettled from scratch three or four times since mankind achieved starflight. Each previous incarnation of civilization having been destroyed for one reason or another.

Re:Oh my God, I'm so affraid!

[RoguePsion]

As Heinlen said: "Earth is too small a basket for mankind to keep all its eggs in."

Re:Oh my God, I'm so affraid!

[dgroskind]

Let's all sit here on this one little godforsaken planet...

When you see how difficult it is keep tiny research stations in Antarctica in operation, never mind self-sustaining, and then consider that Mars is somewhat less hospitable then Antarctica and that Mars is far and away the most hospitable place in the solar system after Earth, it's doubtful that one increases the long-term chances of the species surviving by putting it in extra-terrestrial colonies.

The best place to try to ride out a global catrastrophe is Earth. Whatever the technology that would allow people to survive off of Earth (e.g., self-contained cities, terraforming) it could be deployed with a greater chaance of success on post-apocalyptic Earth than anywhere else.

At best, one might want to store some gear on the moon as kind of off-site backup for civilization. In the event of global catastrophe, some or all of the inventory could be launched automatically to return to Earth.

Re:Oh my God, I'm so affraid!

[lohen]

I very much doubt that the answer to the present population expansion lies in exploring the solar system. At current tech, it would take immense resources to keep even a few colonists on the most suitable planet (Mars). The same as a massively larger population back home.

The real benefits of exploring the solar system would be scientific knowledge and, medium to long term, mining of resources rare on Earth. Colonisation would be very long term - by current estimates, based on predictions for tech improvements, it would take 100 years and a shitload of resources to terraform Mars (based on an article I read in Focus a few years back). It's best that we wait until we really have the tech to do it well, and try to sort out our problems at home at home in the meantime.

Re:Oh my God, I'm so affraid!

[sgage]

"Let's all sit here on this one little godforsaken planet and hope that nothing comes along and does a number on it."

I hate to interrupt your extropian wet dream, but our little planet is the one place that's not "godforsaken" for a long, long distance.

You talk about people being paranoid about nuclear technology (justifiably paranoid, IMO), but you are willing to rush into space because an asteroid might hit us.

Now look, sooner or later we'll figure out how to get into space in a big way. But it's not worth rushing, and it's not worth poisoning the earth. It's a lovely idea to "leave home", but let's not burn down the house (where our parents still live) while we're at it.

Re:Oh my God, I'm so affraid!

[Ozx]

Everything else in the solar system is 'affected to a lethal degree,' and you would essentially be attempting to overcome this... There's no plant life, there're no sure sources of long-term general-purpose fuel, there's lethal quantities of radiation, and none of these places have the biodiversity to support human life through another "development," nor the means to obtain and support such biodiversity in the near future...

Perhaps you should stop taking your science lessons from fiction...

Re:Oh my God, I'm so affraid!

[Cally]

>> - What happens if fission powered rockets crash?
>> Instant nuclear disaster, unless the containment
>> vessel holds (and it might, but the public will not >> be convinced it would).

> Oh, you mean like Chernobyl? Not to make light of
> 100 or so deaths, but there are worse things in the
> world.

*sigh*... All I can say is that if you'd been in Europe in 1986 you'd have a slightly more realistic grasp of the effect of Chernobyl. There are some areas of the UK that are STILL banned from producing milk because the fallout that rained out > 15 years ago is still present in levels high enough to make it unfit for human consumption.

BTW, there's only one "F" in afraid ;p

Re:Oh my God, I'm so affraid!

[Steveftoth]

Does anyone realize that you could launch entire buildings into space with this technology? Think about that, with nuclear fuel powering the launch into space you could launch empire state buildings into space. Not tiny rockets like today, but huge mammoth buildings.That's what will allow us to colonize other planets, chemical rockets will never get us there.

Re:Oh my God, I'm so affraid!

[Anonymous Coward]

Only a hundred deaths at chernobyl? really? that is very interesting, especially since the cancer rates in southern Ukraine and Belorus are higher then anywhere else in the world. So is the number of still-births and deformed children. the effect is more like hunderds of thousands of deaths.

Careful people....[OT]

[univgeek]

This is probably going to end up costing you moderator status... IF you think it is interesting i.e.

Interstellar trips

[Anonymous Coward]

It would also allow slow intersteller trips of around 1% the speed of light.

That's still 400 years to the NEAREST star. What are the chances of better technology being developed before you get there?

Re:Interstellar trips

[spike hay]

Yes. Slow intersteller trips. The ship would probably be passed en route by faster ships. However, it is an easy way to send huge quatities of materials to other stars.
.1 C would be nicer for fast manned missions or probes. That would mean 40 years to Alpha Centauri. That is doable, but would require an enormous amount of fuel.
To reach .1 C, you can use several different methods.

1. Fission fragment sail or reactor.
Uses thin films of highly fissionable Americium as fuel.
The fission fragments from the nuclear reaction escape at very high velocities, propelling the ship very fast. You can't use plutonium in this setup because it cannot fission when formed into thin films. You need thin films for fission fragment propulsion so the fragments can escape.

This setup can reach a specific impulse of 1,000,000,000. 2,000 times more efficient than chemical rockets. However, this gets too expensive when you scale it up beyond a small probe. Americium is fscking expensive, millions of dollars per ounce.

2. Fusion
Fusion's great. Once power fusion reactors come on line, the fuel will be cheap.
There are several different fusion concepts. The closest to being realized is the ant-matter catalyzed fusion type. It blows up little fusion pellets at it's rear. This uses fusionable pellets of Deuterium and Tritium that are surrounded by uranium. A very small quatity of antimatter is fired at it. This starts the fission which then starts the fusion and causes the whole thing to explode.
This could be built in 20 years. Everything is here except the antimatter. You only need a few micrograms of antimatter. We could be producing that pretty soon. It could theoretically reach 200,000 seconds.
There are other types of fusion rockets that could reach 1 million seconds. These use magnets to confine the fusion plasma. Some is leaked out the back for propulsion. However, it's hard to build a self-sustaining fusion reactor. Plus the magnet weight (1,000 tons) would have to be reduced dramatically to be practical at all. That's about 50 to 70 years away.

3. Antimatter-matter
Efficiencies of 10 million seconds
A helluva long ways away. We don't know how to begin producing enough anti-matter.

4. Beamed energy
In the distant future, the best thing for fast intersteller flight.
Just a couple decades down the road, we could build Robert Forward's starwisp probe. It would be 6 kilometers wide and be made of a fine mesh. It would weigh 42 grams, if you can believe that. It would be easily propelled to .2 C by a 10 gigawatt beam of microwaves from an orbital power station. Very easy to do, especialy if we have nanotech.
For manned flights, you need gigantic solar arrays around the sun. Here, I'll talk about a project for a Class 2 civilization. That means one able to harness the power of an entire sun. Say, 100 years down the road, we decide to have thin-film photovoltaics constructed around the sun. That would capture around 1 octillion watts. Anyway, autonomous self-constructing robots and nanobots would get the materails off a large asteroid and begin constructing this. Being very thin solar cells, you'd only need maybe 1,000 square miles of materials. After a few years, we would have a working Dyson sphere.
Some of the power, maybe a quintilion watts could be funneled into lasers and broadcasted to a giant gold-foil sail the size of texas or the US or even much larger. The laser would be able to propel it to .9999 C. The gold-foil sail would be only a couple atoms thick, and supported by a scaffolding of nanotubes. The sail would weigh only a few thousand tons. The payload could be a million tons. That sounds fantastic, but an extremely advanced civilization with nanotech and AI could easily do it.

Anyway,

.01 C like you can reach with the VASIMR would be excellent for intersteller resupply, or sending huge numbers of people for colonization.

Re:Interstellar trips

[spike hay]

Sorry, got to add somthing: For laser propulsion, you need to have a giant gossamer fresnel lens about 600 miles wide around the orbit of Saturn in order to focus the beam onto the lasersail.
Also, lasersails can seperate into 2 parts to stop. 1 part is left behind. The laser focuses light on this sail. It reflects back onto the other sail, stopping it. Once at the target star system, a Dyson sphere can be constructed around that star.

Re:Interstellar trips

[Alibi]

I remember reading about a Bussard ramjet, a proposal for possible future interstellar travel.

The idea is that since interstellar space is not empty, the craft will not have to carry all its own fuel, but can rather use huge magnetic coils (around 10^6 Tesla in strength) to gather its own fuel. It would have to carry enough on-board fuel to reach a certain threshold speed, at which point it begins moving quickly enough to pass through enough space in a given time to gather all the fuel it needs.

It would work by 'funneling' hydrogen, which is the most available (though by no means is it plentiful) gas in interstellar space, into a fusion reactor. Needless to say, this is a long way off, if it will happen at all, but it's a really nifty idea.

Some quick searching reveals a quick once-over here and a more mathematical treatment here.

Re:Interstellar trips

[wurp]

Dude, your repeated use of specifics gives an impression that you know what you're talking about, but your numbers are all fucked up.

1,000,000,000 seconds is 2,000,000 times 500 seconds, not 2,000 times.

There is no way 1000 square miles of material could encompass the sun, the surface area of the sun is much, much higher than this (the surface area of the earth is ~ 200 million square miles). Maybe you meant 1000 cubic miles of material? Or maybe you're just making shit up?

I stopped reading after that point...

Re:Interstellar trips

[pixelated77]

The problem with .999c is that friction (space isn't a perfect vacuum) would melt/vaporize all known materials, so how do you construct a ship/probe that can handle that speed? IIRC, at .3C all known materials melt due to friction...

Re:Interstellar trips

[Anonymous Coward]

I just assumed that he meant 'cubic' miles.

Re:Interstellar trips

[wurp]

Dude, your repeated use of specifics gives an impression that you know what you're talking about, but your numbers are all fucked up.

1,000,000,000 seconds is 2,000,000 times 500 seconds, not 2,000 times.

There is no way 1000 square miles of material could encompass the sun, the surface area of the sun is much, much higher than this (the surface area of the earth is ~ 200 million square miles). Maybe you meant 1000 cubic miles of material? Or maybe you're just making shit up?

I stopped reading after that point...

How the hell is this flamebait? He gave numbers that are BS, I called him on it. Should we not correct people when they get things wrong?

Should lots of detail, with obvious mistakes, not be suspect?

Re:Interstellar trips

[wurp]

I would suspect that if you can get going that fast, you can get enough energy from a Bussard Ramjet engine to power a device to ionize and deflect the material that your ramject can't handle.

Re:Interstellar trips

[Cally]

Jesus, I wish you folks would learn the distinction between fact and fantasy. THIS IS FANTASY. IT IS NEVER GOING TO HAPPEN.

Re:Interstellar trips

[Ryouko]

If you're a Sci-fi fan, think Red Dwarf.

Re:Interstellar trips

[Anonymous Coward]

It is not fantasy...though it is a ways off. As we speak scientists are developing new ways to create and store anti-matter, and technologically speaking a dyson sphere is perfectly reasonable. Maybe not now...but don't forget that if evolutionary biology is correct humans will have millions of years to get it right.

Re:Interstellar trips

[spike hay]

Yeah. I make typos like that. But obviosly I meant cubic miles. Square miles is 2 dimensional. You'd have a very hard time doing anything with that amount of matter.

Anyway, 1,000 square miles is enough. We're talking about 10 atom thick solar cells. Very, very, very thin. Actualy, that might be an overestimate. I've seen figures of only 100 cubic miles needed.

Also, this isn't a star trek dyson sphere. It's just solar arrays floating in orbit so as to capture all of the light. The materials need not be strong.

I am a very poor typist. I meant 1,000,000 seconds, not a billion. A million seconds is 2000 times 500. If you had a rocket with a billion seconds, that would be pretty cool, despite violating the theory of relativity.

When I screw up like that, just try to figure out what I meant.

Re:Interstellar trips

[mshurpik]

The problem with .999c is that friction (space isn't a perfect vacuum) would melt/vaporize all known materials, so how do you construct a ship/probe that can handle that speed? IIRC, at .3C all known materials melt due to friction...


No, the problem with .999c is that THE THEORY OF RELATIVITY prevents it from happening. IIRC you clearly don't RC high school physics class.

How did both you and the guy who responded to you get modded up? This place is insane.

Mod parent down...

[OgdEnigmaX]

Although this info is quite relevant to Slashdot, and of interest for many /. users...unless Lethyos has concluded from the available evidence that Slashdot ought to be nuclearly sent into deep space, where it might perhaps be more profitable, this post most definitely does not belong here.

I'm sorry

[Wind_Walker]

I stopped reading the article when he said the following:

The best a chemical rocket can do is get up to speed (burning up all its propellant in the process) and then drift to its destination, like a car coasting down the highway with its engine off. What's needed are space drives that will provide a constant velocity.

As any high school physics student will tell you, burning up your fuel and then "coasting" the rest of the way means that you're at a constant velocity. Velocity is a vector, with two components: Speed and direction. In space, there's no (significant) drag or friction, and so your velocity is constant. If you were to keep burning fuel, you would keep accelerating (assuming an infinite amount of fuel) which anybody will tell you is not a good thing when you eventually want to stop.

I see no reason to listen to somebody talk about physics when he clearly has no respect for the language.

Re:I'm sorry

[SuiteSisterMary]

Yes, and as any high school physics student will tell you, if you have no fuel, then the only way you have to stop, rather than flipping end for end and applying thrust, is to hit something. Any high school physics student will also tell you that you WANT constant acceleration, NOT constant velocity, because you'll get to your destination faster. After all, all you need do is flip end for end at the half-way point to your destination, and turn your engines back on. Or, put another way, the sudden stop at the end of a fall at Earth normal gravity doesn't hurt because you're travelling at 9.8 meters per second; a one second fall will leave you bruised. No, the sudden stop hurts because you're accelerating 9.8 m/s per second.

Re:I'm sorry

[cott]

Well. Do you have respect for the language?

Velocity is a vector, with two components: Speed and direction

That is wrong as well! Correct: Velocity is a vector, pointing in the direction where the object (the rocket) is going. Its length reflect the speed at which the object is going. In Cartesian 3-space, any vector has 3 components. (x,y,z)

Re:I'm sorry

[jasontheking]

It is a good thing when you want to slow down. Either vector the thrust, or just turn around.

Otherwise you have to rely on pissweak little rockets to put you into orbit around a big rock. And that's a bastard if you screw it up.

Re:I'm sorry

[Wind_Walker]

Actually, we're both right. The velocity vector can be represented by two components: the magnitude of the vector and the (three dimensional) unit vector indicating the direction. The velocity vector can also be represented by an ordered set of 3 components, indicating the x, y, and z magnitudes, from which you can then derive the form I wrote.

For example, let's say that I'm moving at 30 MPH, and going in a direction due North and vertically (z-axis) at a grade of 10 degrees. That describes the velocity vector perfectly.

Alternately, I can say that I'm moving in the North/South direction with (30 MPH * cos(10)), assuming North to be positive, moving East/West at 0 MPH, and vertically at (30 MPH * sin(10)). That's your three-ordered pair (x,y,z) magnitudes.

Both representations perfectly reflect the vector in question; you say po-tay-to, I say po-tah-to. Don't mess with the physicists :-)

Re:I'm sorry

[crosbie]

The stop hurts because you decelerate far faster than 1G (9.8 m/s2).

The hurt is caused by force.

The force is proportional to your mass and its change in velocity (and inversely to the time over which that change takes place).

The soles of our feet while standing are subjected to a force equivalent to a deceleration of 1G.

Jump off a building and unless you land in water or an air bed it will be several Gs indeed.

So, no one gets hurt by accelerating at 1G. In fact this is a problem for cosmonauts, because they're not accelerating at 1G. 1G is what the body prefers, always.

Re:I'm sorry

[Anonymous Coward]

Actually the sudden stop hurts because your acceleration nears infinity for a very brief moment.

Re:I'm sorry

[Wanker]

Like you, my first thought was "heck, I can provide a constant velocity space engine right now!" It's over there!

If you assume that he meant to write "constant acceleration" (or maybe some bozo editor thought that "velocity" read better and heck, it's the same thing, right?), the rest of the article reads much better.

like NMR... call 'em "Water Rockets"

[ghostlibrary]

Nuclear does scare folks. The medical imaging of NMR (Nuclear Magnetic Resonance) got changed to MRI (Magnetic Resonance Imaging) because people were freaking out about the 'nuclear' part. Even though it was passive reading of nuclear states, not actively nuking patients.

There's a good writeup on:

http://www.urbanlegends.com/science/mri_not_nucl ea r.html

The "nuclear rocket" folks could take a page from their book. Call this "water rockets" or such and downplay the nuke, upplay the 'tea kettle' method (or what have you).

Re:like NMR... call 'em "Water Rockets"

[prefect42]

This one's a semi myth. They're not quite the same thing. MRI is a use of NMR. NMR is the principle you're using, and MRI is an application of the principle. It can be called NMRI, and that *is* equivalent to MRI.

As a footnote, I note that my local hospital (Leeds General Infirmary) calls it NMRI.

jh

Re:like NMR... call 'em "Water Rockets"

[leftsaidfred]

"water rockets" are a good idea but already taken.. I think we should try to build a hollow shuttle that holds one have of its volume in water. Then you attach it to a modified hand pump and fill with pressure. Just when you think you can't pump any more air into the ship, you relase a trigger an up it goes, shooting water out! Boy, do I miss those.. that's a clean fuel alternative, maybe NASA should look into that.

obviously you missed the point of that story

[Anonymous Coward]

Also, learn how to close your tags. thx

Yet again.. Another Huntsville, AL reference

[zoid.com]

It's really neat to see all of the Huntsille, AL references on slashdot. Most people think of Alabama as backwoods but Huntsville is the exception. Usually when there is a NASA, Ultra-Wideband or genetic reference then Huntsville is mentioned somewhere.

Re:Yet again.. Another Huntsville, AL reference

[ASimPerson]

Amen. I, too, live in the Huntsville area, and I always get a little smile on my face when I see some positiive converage of the south anywhere.

Fission Rockets: why it didn't work before nor now

[Anonymous Coward]

Come to Oak Ridge and you will find what is called the "Tower Shielding Facility" which was built to support the nuclear-powered airplane at about the same time. The main reason it never "flew" was because one could never shield the earth's surface from the radiation field that would hit all the life on earth. If shielded, it was too heavy to fly. I am going to guess the same problem exists for rockets.

Even bigger news flash ...

[OzPeter]

In parts of this world ... you can actually mix with naked women in social situations, without listening to them. For free, and no strings attached. In fact there is a beach 5km from where I sit where this is true.

Of course this is more difficult in the more progressive USA, where even partly exposing your flesh on the beach is illegal

Re:Even bigger news flash ...

[Anonymous Coward]

Deeply offtopic, but that depends on where you are in the US.

In New York, women can go topless anywhere men can go topless. (Thanks to a NY court ruling making anything else a gender inequity).

There are numerous topless beaches in Florida and the Florida Keys. I would assume California as well. The key point being that these are private, not public, beaches. Not sure if Hawaii does, since IIRC, there isn't any private beaches there (by law).

I agree that the majority of the US is way too hung up on sexuality and body issues, but at least get your facts right :)

Re:Even bigger news flash ...

[ivan256]

Even the prudish state of Massachusets has some nude beaches.

Hickman = VT GRAD

[tube013]

one of the more known grads from vpi

go hokies

Homer WHO?

[Baldrson]

Look... the guy was going great guns until he got hired by NASA. Now he's a media celebrity mouthpiece for them. He probably should have followed Von Braun out the door even though Von Braun wasn't his hero. Von Braun can't be as bad as the scum that took over and made NASA what it is(n't) today.

No

[Anonymous Coward]

Since accelaration is the product of mass and velocity, and velocity is a vector (i.e. magnitude and direction), travelling in a circle will constanly change direction => change velocity => change accelaration.

Re:No

[damn dirty ape]

Acceleration is not the product of mass and velocity. Acceleration is the rate of change of velocity.

You were lucky to post this anonymously; no one will ever know that you forgot what you were taught in your high school physics class. ;)

P.S. you were right about one thing- the acceleration is not constant in circular motion.

He's a celebrity...

[Penguinoflight]

So he speaks to people dumb and smart. Sure, many people complete HS physics, but most of them forget everything.

I am under the impression that he's just dumbing down his speech so everyone kinda understands. That or he's thinking about Mars' atmosphere.

Been there, done that

[Aighearach]

NASA is already sending out hydrogen ion stream rockets, using the magnetic ionizer you're describing. It is a complete success, and many times more efficient than traditional rockets.

As for a scramjet launcher... that is silly. You don't save a lot of money. The major expense in a launch is not the fuel, it's the craft. A reusable craft does not always result in a cheaper launch, because that requires a fancier craft. For example, Shuttle launches are more expensive than disposible rocket launches.

Saturn in a year claim is dubious. Ion propulsion gives slow, steady, efficient thrust, perfect for long cheap trips, but terrible at fast acceleration. Though a combo with chemical early stages, and ion later stages, might work well for a fast distance trip. The actual thrust in the Deep Space craft using ion propultion is about the weight of a sheet of paper... but that really adds up over a few months!

See also: ion faq at NASA

Re:Been there, done that

[Mishra2002]

The point isn't that your saving money on the fuel the point is which launch system you use. A nuclear rocket is not carrying as much mass in fuel as a chemical rocket. While launching a chemical rocket capable of interplanetary transfer may require a launch vehicle the size of an Arienne-5 a nuclear rocket which has less mass may require only a pegasus. -Mishra

bullshit

[QuantumG]

He clearly ment constant acceleration.

too true

[QuantumG]

He ment acceleration, for sure.

"not as dangerous as it sounds"

[Mr.Ned]

Correct me if I'm wrong, but I'm under the impression that sending the fuel off planet is pretty dangerous. If a second Challenger were to happen, all those nuclear materials would be spread out in the atmosphere, which sounds pretty dad-gum dangerous.

Re:"not as dangerous as it sounds"

[Mishra2002]

Prepare to be corrected. It's a common misconception that rockets simply explode for no good reason. while this can happen it's frankly rare on a flight tested vehicle. Usually when a rocket explodes it is detonated by controllers on the ground. The saftey mechanism on a nuclear rocket would most likely be designed to vaporized the uranium, thus sending it into the upper atmosphere where frankly it's not going to hurt anybody. It would take years for the stuff to come down, and would do so in such small amounts there probably wouldn't even be an increase in background radiation.

-Mishra

Re:"not as dangerous as it sounds"

[Anonymous Coward]

The molecular weight of Uranium is enormous. Even as a vapor, the density will be high. Moreover, it will not exist as a vapor for very long. It will become finely divided dust particles. The question "how long" these will stay suspended is a function of the particle size and density. In essense, the drag force on the particle must overpower the gravitational force. In the rarified upper atmosphere, there is not much air to induce drag. On the other hand, Uranium is the one of the most dense elements in existence. Gravity will win. The Uranium will come back down. It would be a problem. The only hope would be that it would be spread over such a large area, that this would not be overly harmful. This means that you must only be carrying small amounts of material. It is just a bad idea.

Re:"not as dangerous as it sounds"

[Anonymous Coward]

Are you trying to imply that ground control detonated challenger?

Re:"not as dangerous as it sounds"

[Anonymous Coward]

Care to specify why it would be a problem?
Uranium is not very radioactive, neither is plutonium, and they are ALPHA RADIATORS, even a damn sheet of paper would be enought to shield you from it, only way to get a cancer would be to inhale the stuff and get it stuck in your lungs for a long time, and as you said, it's molecular weight is enormous, it won't stay airborne long enough for people to really breath too much of the stuff. Their chemical properties as heavy metals are far more dangerous than the amount of radioactivity...

Besides, It's not like there isn't TONS of plutonium and uranium already in the ecosystem resulting from release into atmosphere in all those nuclear weapon tests.

Re:"not as dangerous as it sounds"

[fredrik70]

I believe you would store the nuclear fuel as pellets which would not be vaporated by the explosion, the stuff is most dangerous when you get it inside your body and as long you can keep it together in big chunks you'd be ok... belive that's how they done with satelites they sent of containing nuclear fuel (for electricity).

Re:"not as dangerous as it sounds"

[mpe]

Correct me if I'm wrong, but I'm under the impression that sending the fuel off planet is pretty dangerous. If a second Challenger were to happen, all those nuclear materials would be spread out in the atmosphere, which sounds pretty dad-gum dangerous.

Depends how well protected the fuel was. Even with the violence of the Challenger explosion identifiable pieces of wreckage were recovered. Aircraft carrying nuclear weapons have exploded before now.

Re:"not as dangerous as it sounds"

[zeno_2]

No.. im pretty sure he was saying that the 'usual' way a rocket will explode is because it was on purpose.

Besides challenger, we haven't had too many problems with our shuttle, id say its safer to ship a nuke into space then to ship it across the country by truck, or by jet...

Re:"not as dangerous as it sounds"

[mpe]

Uranium is not very radioactive, neither is plutonium, and they are ALPHA RADIATORS, even a damn sheet of paper would be enought to shield you from it, only way to get a cancer would be to inhale the stuff and get it stuck in your lungs for a long time, and as you said, it's molecular weight is enormous, it won't stay airborne long enough for people to really breath too much of the stuff.

If you has a solid lump of metal the risk is low. However if you have dust, is much more dangerous because it can either be ingested directly or react to form compounds which can be ingested.

Re:"not as dangerous as it sounds"

[Detritus]

It may be a fine point but the range safety officer at a launch complex does not "blow up" the rocket. The range safety systems on rockets are thrust termination systems, designed to terminate powered flight. The goal is to shut down the engines, not to blow up the rocket into many small pieces. This usually involves shaped charges that open the casings of solid fuel rocket motors and the fuel and oxidizer tanks of liquid fuel rocket motors. The desired end result is that the rocket falls in a ballistic trajectory into a safe impact area and does not endanger people on the ground. The range safety officer has an "impact predictor" display that shows where the rocket would land if all of the engines failed at the same time. His job is to push the big red button if there is a risk that the rocket could stray from its predicted trajectory. It may look like they "blew up" the rocket, but that isn't what happened.

Re:"not as dangerous as it sounds"

[Mr.Ned]

>It's a common misconception that rockets simply
>explode for no good reason

Oh, I'm not real worried about them exploding for no good reason - human error has been the problem with all the rocket mishaps I've read about. Stuff like unit conversions, faulty switches, stuff like that happens.

I'm also a little unsure about your claim that vaporizing the uranium would sent it to the upper atmosphere where it won't hurt anyone. Correct me if I'm wrong, but the last thing I'd want would be vaporization - all those nice little particles of uranium ready to be inhaled or cover the surrounding area like the iridium layer did. I doubt they'd go to the upper atmosphere - that'd have to be a pretty damn big safety mechanism considering that when bombs detonate they don't send all the stuff up there.

There was another reply to my post that was talking about putting them in fuel pellets - that seemed like a reasonable way to go about it, provided that they didn't break up or 'vaporize'.

Also, I wouldn't trust a safety mechanism. Who says that can't fail?

Re:"not as dangerous as it sounds"

[Anonymous Coward]

Ingestion of really small amounts (and small amounts they would be, if it is dust) would not be very dangerous if the stuff passes right trough the digestive system, it would not be in one place long enough to cause radiation damage.

But will it, or does it stockpile up in the system like mercury, and some other heavy metals?

Well, how about..

[josh crawley]

The way I see it, there's a continent that's largely uninhabited, yet for a good reason. It's Antartica. Stays at a toasty -120F but there's a huge area of.... nothing.

The Russians have technology of building things in very cold weather (permafrost in and above the Artic circle), and we have much of the hardware tech needed.

The way things are between us and the Russians, perhaps we could get along on this project. However, we need Financial backing of corporations. Governments are usually known to squander away our money without anything to show for it. A few Corps. will fix the government bloat.

The main reason suggesting Antartica is that even-if a nuclear shuttle does go the way of Challenger, Who's it going to hurt? The drift radiation would be surely no more than usually gotten in cosmic ray bombardment (70 rad/year).

Re:Well, how about..

[Cef]

You still really don't want any sort of radiation or radiation leak in Antartica, even if the risk might be low. One thing history has taught us is that statistics might make us feel safe, but we rarely are. We also grow complacent, and then disaster befalls us.

However Antartica and the Artic would be an ideal place to build a rail-gun transport system, using magnetism to build up speed and takeoff velocity. Getting up to speed from nothing is by far the most fuel consuming part of the process.

Once you leave the launch ramp, you can use conventional Liquid Oxygen/Hydrogren fuels to get out of the atmosphere. LOx & LH are probably the BEST choices for use, simply because the byproduct is water, and not a pollutant like most of the other propellant mixes. And dropping water vapor over the polar cap is not going to do it any harm, more likely do it some good.

The cold is a useful ally for such a setup. Less energy required to put oxygen and hydrogen into a liquid form, an abundance of water for producing oxygen and hydrogen via electrolysis, and a huge amount of wind and solar energy that can be harvested for power (in the right locations). There is also the semi-conductor properties that some substances exhibit in cold conditions that could be exploited.

Once launched, an orbiting docking facility can then fuel up a craft for longer hauls. With decent designs, the propulsion unit would be separate (and have a standard docking system) allowing changeover in orbit for another unit more suited for the job at hand, such as a nuclear propulsion unit for intra-solar missions, or one of the many other propulsion systems that are in the works.

If someone comes up with a smaller or more efficient engine design, a standard docking system between the propulsion unit and the craft allows easy retrofitting and upgrading. Craft returning to the Earth can bring back propulsion units so they can be tested, retrofitted, refueled and relaunched on the next craft.

Anyway, enough rant, I've got across my point.

Re:Well, how about..

[resident machinist]

Well, you get more "kick" when you launch from the equator.

Re:Well, how about..

[Anonymous Coward]

Governments are usually known for squandering away our money without anything to show for it

I think you've got the role of Government and Commercial confused, they act very differently. Commerical enterprises are there to make money, they generate a return on investment; if the path is too uncertain or too risky a commercial enterprise will just not do it. Basically, if there isn't profit to be found in the activity, a company won't do it. This usually boils down to items that are public goods, that is stuff that does not have significant "free ridership". A police force, roads and bridges, long-term research, etc. are examples of this latter case. Companies just won't engage here; too uncertain, too risky -- not a clear way to charge for the result.

Thus, goverments do these sorts of things. Governments are also the right place to have "monopolies", i.e., natural singeltons. If there can only be one of something, then it must be controlled by a democracy; if it isn't then the only alternative is a dictatorship. Companies have a dictatorship for control, that's why they are efficient. But, with too much power, that's also why they are dangerous. As long as there can be competition for a good or service, it belongs in the commercial zone, but very high risk, public good stuff, and natural (perpetual) singletons are the right place for government.

Now, you mention that governmetn is inneficient. Yes, due to politics. Politics is not a dirty word; it is people working out their differences -- sometimes it is painfully slow or irritating. Howevre, it's better than war and it's better than a dicatorship. So, the inneficicy is OK beacuse the alternative is worse; either something not getting done that should or someone controlling everything.

Now to the topic of space travel. There is a reason why it is, up till now, been a governmental activity. First, it's bloody expensive and the pay-offs aren't that great or are uncertain. Thus, it's high-uncertanty and very expensive. Nothing stoping a company from entering the market and going-it-alone if they wish... it just doens't make sense to do so. When the costs are so high, you don't want duplicate efforts (even though each duplicate may be efficient). Also, the primary goal of space exploration is to learn more about nature... try selling that to a bunch of investors. Sorry. Next. Have you ever tried to get venture capitol?
Anyway, I'm SICK of people trashing government when they don't have a goddam clue what government is there for (and what it's not for).

Re:Well, how about..

[robhancock]

Except that the polar regions are where the most energy is required to launch something into space - for the most efficiency you need to launch near the equator to get a boost from the earth's rotation..

Re:Well, how about..

[josh crawley]

I know, thats why there's Kennedy's Cape Canaveral. Conserves fuel due top spin, right?

Orion

[Anonymous Coward]

Forget fission engines. . .there are plenty of spare nukes around from the old Soviet countries. Instead of just stashing them in an unused piece of desert, let's build an Orion fleet!

For those who don't know, an Orion-type launch vehicle is basically a heavily shielded crew area (lead is well thought of :-D). Mount on some Cheyenne Mtn. size springs to absorb shock. Under that put a big bay full of nukes. Drop a nuke down the hatch and light it up. Exhaust out the bottom. Wash, rinse and repeat as needed. Betcha that pup accelerates out of the gravity well in a hurry. Think of dropping M-80's down a beefed up Pringles can.

OK, you really don't need Cheyenne Mtn. springs, but you do want to soak up the shock. Weight penalties need not apply, at least not in the sense of current chem-powered craft, where kilograms are significant.

Did anyone spot the real flaw in Orion? No, not the fallout---we have plenty of trashed-out test grounds to use, anyway. The problem is that even with massive payload capacity, it would probably be difficult to boost enough nukes to keep accelerating to anywhere interesting and profitable, such as the asteroid belt.

Anyway, we took the first real step in constant-boost craft already---Deep Space One. It only accelerated at about 1/1000th G, if I recall correctly, but it far exceeded expectations. That's the same acceleration you can expect from a light-sail craft, BTW, and will get you to Pluto and back in about 3 1/2 years. That's what it took to circumnavigate the Earth in the days of Magellan. But light-sails can't carry much payload. But a big brother to DS1, a real ion-powered booster, with a good ram-scoop attached to collect fual mass, could get you somewhere quickly, as Solar System distances go.

I'm sleepy and a tad incoherent---sorry. still, let's get busy and build some real constant-boost craft! Thar's metal in them thar asteroids!

Hail Bob,
Mal the Elder

Re:Orion

[Decimal Dave]

I remember seeing slow-motion video footage of one of the Orion prototypes. It was scaled down and used conventional explosives instead of real nukes. It was conical in shape and dropped timed charges that would detonate in succession to propel the craft. The accelerations were extremely violent and the engineers had to design a sophisticated shock-absorbing mechanism to keep the craft from being crushed.

I think one problem with the idea was that a full-sized ship would require thousands of standalone fission bombs. It doesn't take much imagination to view this as an orbiting dispenser of nuclear death.

Re:Orion

[Anonymous Coward]

Wasn't that a NOVA episode?

It was a super-secret project right after WWII.

I saw one of the aging, retired engineers say with almost a tear in his eye, "I wanted to go to jupiter."

peace

Re:Orion

[jonerik]

A pretty good website on the history and science behind the Orion proposal can be found here.

actually ...

[Edmund Blackadder]

i have found that many of those "hippies" are very well informed about how nuclear reactors work.

I learn more about nukes from then than from the average government or industry nuclear supporter.

Re:actually ...

[MtViewGuy]

Total ridiculous b.s.

Do these "hippies" know about physics and engineering design involved in fission power plants? Maybe ask them have they gone through the US Navy nuclear propulsion training program, where you learn everything involved in fission power plant design, including all the pluses and minuses of various reactor designs.

If you want to blame the problems of nuclear power blame it on the former Soviet Union. Between poor reactor designs, insufficient safety factors (besides the Chernobyl accident, the Soviet Navy lost several submarines due to reactor accidents), and nuclear waste storage in open pits, they should be faulted for doing all the wrong things about nuclear power in general.

Sounds Familiar

[DeadBugs]

Don't we already have fission capable rockets and wasn't there an article about who we have them pointed at?

Better idea

[Anonymous Coward]

Can't we just use Commander Taco for the source of fuel after he pulls an all-nighter at the Taco Bell?

must modularize

[oo7tushar]

The whole space program is still following its trend of keeping large modules as a whole.
The whole premise is: "if we have one large system that has few parts then less can go wrong". That is an obviously flawed system as many things still go wrong. In fact the systems that have been designed as modularized have only failed once (space shuttle O ring, 1986. Where as the moon lander never once malfunctioned). Most problems in space happen due to problems not with main systems but to smaller malfunctions like a clogged pipe (not inherent in the design or function of the overall system).
But I digress, outer space is not a good environment for large thurst engines, smaller long lasting engines are good. That compares to the large engines required to leave Earths initial gravity. Again, we try to adapt one engine to both systems.
As previously posted, high thurst reusable efficient engines for getting a space ship out of our atmosphere and into a different environment (you don't see me driving a car in the Marianas trench).
The reasons that modularized systems don't fail is because we think they're going to fail so we study them to death and make them really safe, thus no failure.

Re:must modularize

[amacbride]

...flawed system as many things still go wrong. In fact the systems that have been designed as modularized have only failed once (space shuttle O ring, 1986. Where as the moon lander never once malfunctioned). Most problems in ...

Um, didn't you ever hear of Apollo 13? While I will grant you that the lander itself didn't malfunction, the explosion in the Service Module wasn't part of the original design...just ask Tom Hanks.

Re:Fission? He's GOT to be kidding!

[mcelrath]

Now, if someone could finally get fusion rockets to work, I think we could finally go someplace.

No one has been doing research on nuclear rockets for 30 years. How long will we let our fear keep our technology from advancing? We can make "bunker busters" and reactors that fit in the bed of a truck. What if some of that effort and those new developments were applied to nuclear rockets? Would they be smaller? faster? safer? You bet.

But I am skeptical about using fission for manned missions.

How long will our fear make our decisions for us? How long will we hide in the closet with the blanket over our heads awaiting the impending World War III? How can we know if a safe manned mission can be designed if our fear prevents from doing any research at all?

It is clear that nuclear power has an energy density far superior to any chemical rocket. It is clear that we will never do anything useful on the moon or mars if the only way to get there is the Saturn V.

-- Bob

nuclear something

[oo7tushar]

I've seen a lot of posts about people getting very worried about radiation. Perhaps fussion is the answer, it seems we may be pretty close: that fusion article from last week.

Seems to be much safer and more efficient.

future technologies

[bartyboy]

Future technologies may give us speeds which double, triple or even increase hundredfolds our current speed records.

So if you're sending a ship to a system that's 50 light-years away and a propulsion system capable of light speed is invented 100 years later, our ship would be passed by the new one, no?

So why don't we hold off deep-space exploration until we have the technology for it?

Re:future technologies

[Dyolf Knip]

Same reason we keep buying new computers even though we know it'll be outdated by the time we get it home. We have to do something or we'll forever be sitting at home saying, "Just one more doubling of processor speed and I'll upgrade". A bird in the hand is worth 2 next year, as it were.

Re:future technologies

[mamba-mamba]

How do you think we will ever develop that technology if we don't take steps now? When you don't study and play (in a scientific/engineering way) with technology, you won't see advances in that technology.

Besides, no one is talking about deep space exploration. We are only talking about going to the end of the solar-system or so.

What a dishonest article

[Edmund Blackadder]

It is really annoying when some one arguing from authority (i am a rocket scientist, listen to me) gives you misleading information.

Nuclear engines are much more dangerous than chemical ones.

If a chemical rocket develops problems on ascent ground control push a button and blow it up.

What if that rocket has a shitload of uranium or plutonium on board?

We have sent nuclear material up in rockets withsome nuclear powered stelites but they have a really negligable ammount of radiactive stuff in them, compared with what is needed for a mission to mars.

And if you think that rockets do not blow up on ascent any more you have not seen NASA's record recently.

So there you have it - thats a risk that he did not mention although it is a very relevant factor. Now you may say - the risk is not that great, or it is worth it, but it should have been mentioned in an honest article.

And also the thing he said about getting energy from space is such BS. If he knows as much about nuclear power as he pretends to he should know that we have enough uranium to give us energy for a loooong time and nuclear powerplants are much safer than nuclear rockets.

Re:What a dishonest article

[shogun]

If a chemical rocket develops problems on ascent ground control push a button and blow it up.

So its not a problem all the aluminium oxides and related chemicals that will be released into the atmosphere and surrouding environment by such an explosion?

Re:What a dishonest article

[jeff.paulsen]

Nuclear engines are much more dangerous than chemical ones. If a chemical rocket develops problems on ascent ground control push a button and blow it up. What if that rocket has a shitload of uranium or plutonium on board?

But why would we want to blow it up? It's not like it's full of rocket fuel or anything - it just has some radioactive stuff in it. The radioactive stuff is solid, and even if we make a full-acceleration nosedive into basalt (which we won't, because all we have to do to stop the thrust is dump the reaction mass, not to mention parachutes), the worst that's going to happen (assuming decent reactor design, like a pebble bed reactor, if they scale that small) is that you get a few chunks of radioactive material; there isn't enough energy involved to get a pulverizing effect. Men with geiger counters go find it and clean it up.

Nuclear rockets are safer than chemical rockets (provided that the reaction mass used is something basically low-energy, like CO2 or H2O, rather than H2 or H2O2). It's like the difference between a low-pressure solar steam engine and a dragster running on nitromethanol, and you're asking about what to do if the steam engine catches fire because of the flaming exhaust it doesn't have. The risk of boost-phase abort requiring the destruction of the craft in atomic rockets is very, very low.

If you want to have something to attack nuclear rocketry on, look into on what effect the very slightly radioactive exhaust trails will have in the ionosphere. Man-made Van Allen belts? Could be, if there's enough energy. Would there be? What would those do? How radioactive would each particle of reaction mass be? How many of them would there be, and what would happen to them, during the atomic rocket's atmospheric boost phase? What kind of reactor would it have? What are this reactor's modes of failure? Is there a reactor that is, by design, immune to modes of failure we want to be particularly concerned about?

Not all of these questions were addressed by Hickam, either, but that doesn't make the article dishonest.

Re:What a dishonest article

[Wonda]

not all that long, at the current useage rate of the currently known amount of uranium, we'll be out of it in 65 years see http://www.iaea.or.at/worldatom/Press/P_release/20 00/prn2600.shtml, if everyone switches to nuclear power, it'll probably be more like 30 years or less, the article mentions that they expect there is enough to go on for 300 years, but they said that more oil would be found as well, doesn't seem to happen lately (no significant amounts anyway)

Re:What a dishonest article

[CommieLib]

Firstly, IANARS.

You substitute one fallacy (ad authoritem) with another (begging the question)...

Anyhow, the big difference between a nuclear rocket and a chemical rocket "blowing up" (to use a technical term) is that while a chemical rocket is loading to the gills with volatile fuel, a nuke rocket will just sputter out. While there's pressure in the engine, there's not a office building full of volatile fuel in the equation. This makes nuke rockets somewhat safer than conventional rockets.

The worst case scenario, of course, is a catastophic mid-launch failure that scatters nuclear material over a wide area. I've read conflicting reports, though one source for which I have tremendous respect, physicist Michio Kaku has argued vehemently against nuke rockets for this reason.

It seems to me, however, that this is not an insurmountable problem. Believe it or not, it is possible for items to survive ground zero of a nucelar explosion relatively unscathed. Now steel spheres are a long way from a working nuclear core, but perhaps we let ourselves be emotionally carried away by the visual violence of an explosion: "nothing could survive that." Well, yes some things could survive that. Perhaps we just need to build engine cores that could...

agree

[Edmund Blackadder]

this guy sounds like fusking marketing exec giving out simplistic and misleading info the get more funding.

Re:agree

[Anonymous Coward]

At least he manages to sound intelligent, so you could obviously learn something from him. "the get more funding"? What the fuck are you taking? Try coming down off it before you make yourself look more stupid than you really are. (Or maybe you really are that stupid and someone helps you manage the /. interface?)

Re:What a dishonest PERSON

[josh crawley]

Heh, with the amount of stupid spelling errors coupled with what seems to be the neo-hippie speak, you seem to be just one of those types mentioned in an earlier article.

Dod you hear them say "nu-cl-ear" ? Better start running with your signs up to the nation capital! Hurry!

Nuclear is not most environmentaly friendly

[Edmund Blackadder]

There are many places where you can put those windmills without cutting down trees. There are many places u can put solar panels. Sorry but there are so many more environmentally friendly powersources.

Re:Nuclear is not most environmentaly friendly

[Anonymous Coward]

There are many places u can put solar panels. Sorry but there are so many more environmentally friendly powersources.

You are wrong. The sad thing is, you probably believe yourself to be some kind of "environmentalist", not realizing that you are advocating some of the most polluting forms of energy known to man. The facts are that nuclear power is clean and safe. The construction of solar panels is so harmful to the environment that even lignite coal is a more environmentally friendly solution.

Re:Nuclear is not most environmentaly friendly

[Anonymous Coward]

Great.

"Wow, where is that scenic mountain they were talking about int he tour guide?"

"It's under all those goddamned windmills."

Re:Nuclear is not most environmentaly friendly

[5KVGhost]

I'm sure we'd find all sorts of environmental impact when scaling up the "friendly" power sources enough to be practical.

Windmills can chop up migrating birds, and enough of them can interfere with local wind patterns. Acres of solar panels out in the desert result in what's essentially a huge silicon parking lot, killing off the desert life underneath and creating hot spots that may have unanticipated effects on the local weather.

There's no such thing as a power source that doesn't have some environmental impact. The problem is that some environmentalists have decided that certain technologies should recieve more scrutiny than others. It's dishonest. I'm not saying that we have the best of all possible power infrastructures, but we need less FUD and hype and more rational consideration of all the alternatives.

Re:Nuclear is not most environmentaly friendly

[ryanwright]

There are many places where you can put those windmills without cutting down trees. There are many places u can put solar panels. Sorry but there are so many more environmentally friendly powersources.

You're right, of course, but the issue is not ability, it's practicality. Given the costs of various energy production methods, nuclear is the best and the cleanest available to us. Wind turbines and solar are nice, but they're too damn expensive per Kwh.

Personally, I would like to see the US Government pour billions into solar research. It would be nice to be able to slap solar-generating shingles on every home for a reasonable price.

Hydroelectric dams are the best things we've got going. The energy is clean and incredibly cheap. Unfortunately, the various terrorist groups operating in the US are forcing us to tear our best energy producers down to save the salmon, even though there is absolutely no proof that dams are the reason for the decline in salmon population. As if the people pulling them out of the river by the ton to sell in supermarkets have absolutely nothing to do with it...

Project Pluto - another nuke powered rocker

[avitzur]

He doesn't mention Project Pluto! It doesn't really support his repetition of perfectly safe and all that. http://www.merkle.com/pluto/

"What they came up with was SLAM, for Supersonic Low-Altitude Missile. SLAM was to use a revolutionary new type of propulsion: nuclear ramjet power. The project to build the weapon's nuclear reactor was given the code name "Pluto," which also came to refer to the weapon itself. SLAM's simple but revolutionary design called for the use of nuclear ramjet power, which would give the missile virtually unlimited range. Air forced into a duct as the missile flew would be heated by the reactor, causing it to expand, and exhaust out the back, providing thrust. Pluto's namesake was Roman mythology's ruler of the underworld -- seemingly an apt inspiration for a locomotive-size missile that would travel at near-treetop level at three times the speed of sound, tossing out hydrogen bombs as it roared overhead. Pluto's designers calculated that its shock wave alone might kill people on the ground. Then there was the problem of fallout. In addition to gamma and neutron radiation from the unshielded reactor, Pluto's nuclear ramjet would spew fission fragments out in its exhaust as it flew by. (One enterprising weaponeer had a plan to turn an obvious peace-time liability into a wartime asset: he suggested flying the radioactive rocket back and forth over the Soviet Union after it had dropped its bombs.)"

Re:Project Pluto - another nuke powered rocker

[jonerik]

He doesn't mention Project Pluto! It doesn't really support his repetition of perfectly safe and all that.

The Discovery Wings channel has a documentary on the Pluto project that's well worth watching. I've seen it two or three times myself. A functional Pluto cruise missile was never built, but it would have been a behemoth; "locomotive-size missile" is not hyperbole here. The engine worked quite well in ground tests, though, all things considered. The project ended for a couple of reasons. One was that by the early '60s ICBMs were turning out to be a much more practical way to lob nukes at an enemy. Another reason was that no one could figure out a practical way to flight-test the thing. One idea was to put it on a tether and fly it around the testing range that way, but the mental image of a practically unstoppable fission-powered cruise missile breaking free from its tether and flying over downtown Las Vegas at treetop height was all the Air Force needed to give up on that idea.

You called me dishonest

[Edmund Blackadder]

So please tell me where and how was I being dishonest. Notice how when i called the writer dishonest I did not resort to silly personal attacks, but clearly showed how he was misleading his readers.

And if you accuse someone of having spelling errors, then be really careful you don't have them either because then you just look like an ass.

interesting link

[earache]

There are pages here that discuss nuclear propulsion techniques and demonstrates their superior potential over chemical rockets. Interesting read ...

There is plenty of hydrogen here on Earth

[CodeBuster]

It seems logical that we should look for fossil fuel replacements here on Earth rather than looking in space. At least for the time being there is still plenty of water on the earth, which stores a vast reserve of hydrogen. The technology to separate the hydrogen from the water is well known and when this is combined with the alternative sources mentioned in the article (solar, wind, and geothermal) there should be enough energy to satisfy our needs. It is still important to develop propulsion systems for our next generation of spacecraft. However, our more immediate energy requirements can be satisfied by the resources available here on Earth. The Earth's estimated current supply of fossil fuels will most probably supply our energy needs for the next 300 years or so give or take a decade or two. After that, we can switch to hydrogen and the aforementioned alternative sources as a replacement. The ultimate technology would of course be fusion power and for that we will also need hydrogen or perhaps some of that helium3.

Just turn the ship's lights out while refueling

[U96]

To guard against the photosentitive green goo monster...

He's right. And it's sad,

[Animats]

Space travel with chemical rockets just barely works. You need too much rocket to lift too little payload. The excuse for space travel we have now works, such as it does, only because of desperate weight reduction, narrow safety margins, and throwing away much or all of the vehicle during each flight. This hasn't improved in thirty years, and it's not going to. There are basic limits to what you can do with chemical fuels, and they were reached long ago.

This guy is right. And it's sad.

A fission rocket could work. Working prototypes were built in the 1950s. But the safety problem seems hopeless. A crash would be a major radioactive mess, and eventually, a crash is likely.

Re:He's right. And it's sad,

[Anonymous Coward]

I belive the original tests were for a drive engine designed for a spacecraft to be built in earth orbit. I don't think that the nuclear powered engines were ever to be used to reach orbit.

In this case, the nuclear materials could be lifted in fractional amounts in "indestructable" containers and joined in orbit. Somewhat less risk...

Take baby steps

[Anonymous Coward]

Regardless of whether you think fission is safe
the fact is we're not very good at it. Maybe it's
due to human error but unless you're sending robots up there we need to slow down and think
first.

Aside from the fission danger why are we talking
about going to Mars when the moon hasn't been
explored fully first? You don't learn to crawl
then join the Boston Marathon the next day.

Necessity is the mother of invention and I suspect
that if people travelled to and lived on the moon
we'd learn more about space flight and develop
better technologies from practical experience.

I don't think the Wright brothers drew up plans
for the Concorde, they stuck to basic ideas and
got us in the sky. Later generations are the ones
supposed to figure out how to get to Mars.

Re:Take baby steps

[forged]

(Score:0)

It's weird that your post was not modded up, because your ideas certainely were interesting.

It already happened?

[BlueboyX]

You are worried about nukes going off on US soil? Guess what, It has already happened. Repeatedly. The difference is that the test site was in the central US as opposed to one of the coasts. But that doesn't mean thousands of Americans didn't die from it. These tests were done upwind of a town; they died of cancer...

(Area 51 is well known, but have you ever wondered where that name came from? It is a bomb grid reference. The place is radioactive.)

It is no secret, but since it hasn't gotten air time on the news alot of people don't seem to know about this. I have relatives who could see the mushroom clowds periodically from their homes.It's almost kind of like the rocket engine tests that produce huge clowds visable from Sandy, Utah. Alot of people have seen them, but few non-locals know about it.

Re:It already happened?

[Physics Dude]

These tests were done upwind of a town; they died of cancer...

You have no idea what you're talking about. Please get a clue before posting this kind of drivel.

Re:It already happened?

[Uart]

at the end of WWII and shortly after they used to test nukes in the deserts of the western US, this sometimes would happen near a town and cause a "mini-chernobyl" effect (cancer and birth defects would increase by a crapload). So he does have some idea what he's talking about. Though I do believe Area 51 is an Air Force designation that has nothing to do with what he said.

well this hick yum has this to say

[Anonymous Coward]

when g.k.o. spoke before congress, and they decided to be sloth like lizards,,,,,,well yeah years later a few kids found out about that jive.

lets see now,,,, wank worm was created by who/m?

oh yeah its not known, heh.

What am eye doing speaking here,,,,yawn waste'n time i guess, just about to task the "_ property division" of some gov in the few months,,,,,had to reverse engi some stuff and figure talking to the thugs that held up the data is Prudent at Ziss Juncture.

heh text to laff conversion is in order.

Are you sure?

[SkulkCU]

just won't happen anytime soon

While NASA's funding is down, the funding to nuclear programs, specifically, is UP. This could mean (a) Bush's energy plan is looking everywhere for power or (b) somebody realized this was the next propultion system.

Re:Are you sure?

[JabberWokky]

While NASA's funding is down, the funding to nuclear programs, specifically, is UP. This could mean (a) Bush's energy plan is looking everywhere for power or (b) somebody realized this was the next propultion system.

The DoD budget is also up. The "next" propulsion system is in use already (or very close to it). Look up Rocketplane (look at the "out and back in" military record of the president and founder), or the "Aurora" sightings (be aware like all outside accounts about classified aircraft there are also plenty of conspiracy BS about it, but some of it is very reasonable and documented). Even if neither of those is the primary focus of the US military getting to space, I have no doubt at all that they have their ways, other than the old reliable Titans.

Other key facts to look at include the fact that all the US military projections of near future battles work on the assumption of US space superiority and ability to fly birds on demand. I seriously doubt that the US DoD depends that much on NASA for such things.

Drawbacks? Simple - the US military dosen't want anybody else in space, or it loses that crucial high ground. That means other countries and civilians (including corporations like airlines, FedEx and hotels that *want* to get up there) are left out. Also NASA. The other aspect is that all military applications are pretty much limited to orbital to LaGrange space. That means that everything from the moon to the rest of the system is considered "useless".

Does this mean that I think there is a vast conspiracy and nobody will be able to get to space without MiBs knocking on the door and burning the plans? No. Do I think that there is an active discouragment of "uncontrolled" development of space technology? Yes... to what degree, I don't know. It may be very mild and just what we see publically (lowering NASA's budget), or it might be very strong (the DoD buying up tech companies that show promise). Regardless, it keeps me and my children out of space (unless they wind up wearing a US uniform), and that pisses me off.

--
Evan

Go read the World Health Organization Report

[Erris]

Thousands of birth defects? Who told you that, Greenpeace? Here is a nice sober paper for you. Outside preventable exposures in radiation workers and children, there are no statistically noticible differences.

I've read the World Health Organization's ten year report and I'd point to it if I could. Unfortunately, that one and a new one are not free information. Order it or go visit a library.

I'm not going to say there are no risks, what I'll ask you to do is weigh the risks of doing nothing. The shutdown of the US space program is a national embarassment. We beat up all the lions, tigers and bears. Even the baboons gave up (Appologies to W. Chruchill). The world is watching us and they expect results. We should show them that it is better co-operate and create new resources than it is to squabble over and destroy old ones. If we wait too long, we may no longer be able to afford the effort.

Re:Go read the World Health Organization Report

[robmered]

The WHO, cited here, "linked nearly 700 cases of thyroid cancer among children and adolescents to the Chernobyl accident". In the same source, UNSCEAR linked "some 1,800 cases of thyroid cancer" to the accident. Note that the cited source is an advocate of nuclear energy for electricity production.

Ok. These aren't birth defects, but the central point remains.

Re:Go read the World Health Organization Report

[Erris]

The WHO, cited here [world-nuclear.org], "linked nearly 700 cases of thyroid cancer among children and adolescents to the Chernobyl accident". In the same source, UNSCEAR linked "some 1,800 cases of thyroid cancer" to the accident. Note that the cited source is an advocate of nuclear energy for electricity production.

Ok. These aren't birth defects, but the central point remains.

Uhhh, what's the point? Thyroid cancer is both preventable and curable. It happens because airborn radioactive iodine concentrates in your thyroid. It can be prevented by taking massive doses of non radioactive iodine before exposure. It can be cured later, but obviously this is not desirable. Tens of thousands of "human robots" were thrown into the mess and forced to recieve much larger than necessary doses. If you look into the report, you will see that these numbers are taken into account to provide the overall mortality cited. It will be in the hundreds (180 or so), not the tens of thousands, and there are no expected increases in birth defects and other horrors.

A crashing nuclear rocket will be of comprable scale. It's a significant risk, but one that should be weighed correctly.

X-34

[belg4mit]

What we need is the X-34.
At least for the local stuff,
much more bang for your bang
than the current system and
much safer the fissile material.

Nuclear Problems

[Anonymous Coward]

Quite a few people have mentioned coments both for and against nuclear power. I work with the stuff so I'd like to put in my 2c. First off It is a safe, reliable form of power. There however have been accidents, as occur in every industry; however, as several other coments have stated they have all been operator error. I will admit that even though components fail in nuclear power applications, they fail in ever application (who hasnt had their car break down?). On top of this, operator error is avoidable by putting in so many safty systems that a trained monkey could operate a plant, then training the people who run the plant to the point where they could keep it safe without the safty features. The U.S. Navy is a prime example, although there have been minor accidents the problems have been corrected quickly and properly. Much better than most industrys where many people have to DIE before action is taken. I personaly belive that nuclear fission, or possibly fusion will be our ticket to explore the solar system and beyond, but first people have to realize that nuclear power by itself is not bad, it is the foolish use of nuclear power that is (case and point Cherynoble). Also with proper design radiation is no longer a big worry. You dont see Aircraft Carriers and Submarines being kicked out of harbor, and this is because people do their job right, and do it so well nobody cares. If you want to start worrying about dangers with energy supplies, outlaw coal mining. And as my finnal note, a nuclear powered ion engine is the way to go, research has been done for years on ion engines, and putting an energy generating nuclear platform in space is easier than most think. So why not use a fairly limitless energy supply to power an ion engine?

Wish I could say more, but then I'd have to kill ya...

We're all forgetting something important.

[LWolenczak]

Everybody forgot we now have impulse drive! Even here on slashdot, articals have been posted pointing out that we are one step from warp drive, the part about getting something inside the warp bouble.

Matter/Anti-Matter Engines

[Anonymous Coward]

Matter/anti-matter engines are more efficient than fission engines. According to Zephram Cochran, these engines should take us to Pluto and back in 24 hours.

Bad Idea, here's why--

[schmaltz]

First, there's the well-documented high failure rate of launch vehicals -about 5% for the US, 10-20% for rest of the world. This figure doesn't include experiments or tests.

Second, the atmospheric reentry of one lost rocket schlepping clicking-hot material up the well can lead to the atomization and dispersal of that material in the atmosphere, transforming the earth into a mutants' menagerie.

The Space Shuttle has experienced a lower failure rate than the rest of US launchers, about one in one hundred.

There was an uproar a few years ago, about the Cassini probe. That probe, containing over 32 KG of plutonium, was lifted by a launcher which, at the time, had a one in twenty failure rate, and was due for another.

Additionally, there have already been three catastrophic failures of launchers with plutonium-containing payloads, resulting in world-wide atmospheric dispersal of a hundreds of curies worth of plutonium.

Personally, I don't have a problem with the idea nuclear power or fission-powered space travel. But there remain serious development before it becomes considerably safer. This isn't a marketing campaign, you can't convince knowledgeable people with images of spouting teapots, not when life on this planet is at risk. Nor will risk management white-wash keep people from realizing there's a definite, likely risk that people will die from an accident. [I work in risk management.]

So, what's more important, do we need to do this now, now, now? Or can it wait a decade or three, until we have nuke power better figured out? My vote is to wait a bit.

Re: Bad Idea, here's why--

[erlando]

There was an uproar a few years ago, about the Cassini probe. That probe, containing over 32 KG of plutonium, was lifted by a launcher which, at the time, had a one in twenty failure rate, and was due for another.

Here's a fact for you. One in twenty doesn't really mean that once you've launched 19 rockets without failure the next one will go boom! .. It just means that there is a 5% risc that it does go boom. It isn't cumulative.

But I agree with you. A lot of research remains for this to become safe. But I also agree with the article. We need new energy-sources. And we might need to travel far to get to them.

Re: Bad Idea, here's why--

[fredrik70]

quite handy if it was you just send up every 20th rocket empty and then you were back in business with the 21th one!!! ;-)

Re: Bad Idea, here's why--

[Anonymous Coward]

That probe, containing over 32 KG of plutonium, was lifted by a launcher which, at the time, had a one in twenty failure rate, and was due for another.

Due for another? I suppose you knew some way of divining this from your "work in risk management", huh? Does that background include tarot cards, ouiji boards, and a crystal ball?

An exercise for the student

[leonbrooks]

Once at the target star system, a Dyson sphere can be constructed around that star.

Yup, just whip a handy-handy Sears Roebuck discount Dyson Sphere out of your back pocket, follow the directions, and you'll have your own private Dyson sphere in minutes, just like on the movies... no worries, mate! (-:

Re:An exercise for the student

[sketerpot]

This is assuming that we have enough technology to be able to make the propulsion system. Then a dyson sphere wouldn't be too hard.

Right now, I wish that some black monoliths would come along and give us one of those spheres...

Re:An exercise for the student

[ShooterNeo]

It wouldn't take very long. Three easy steps.

(1) Crewmember on spacecraft says to FriendlyHal the AI "build me a Dyson sphere around that star over there yonder".
(2) FriendlyHal 9000 version. 2.0 (verson 1.0 had a small problem...) sends out a small, self contained machine (small I mean a few thousand tons). This machine goes to the nearest source of usable mass, an asteroid around the target system, and starts converting that mass into building a second one of these machines.
(3) these 2 machines start building more copies of themselves, and so on...
In a VERY short period of time (10 years? 20?) (exponential growth) there are billions of these machines. Like bacteria in a sucrose solution, the raw materials and energy for these machines are very abundant around a star system. At some point whatever planets are here are being torn apart to make more machines. Finally, this vast array builds the Dysonsphere in a few months.

An exercise for the reader

[leonbrooks]

Once at the target star system, a Dyson sphere can be constructed around that star.

Yup, just whip a handy-handy Sears Roebuck discount Dyson Sphere out of your back pocket, follow the directions, and you'll have your own private Dyson sphere in minutes, just like on the movies... no worries, mate! (-:

Re:An exercise for the reader

[spike hay]

With the Dyson sphere, I'm talking REALLY ADVANCED. It would make Star Trek look like cave men.

It seems we really are afraid of fear itself!

[bertok]

It seems that nuclear powered rockets are a great idea, but NASA seems to be balking at the idea because they're afraid that the general population is going to be afraid. There is no real danger of course, but that doesn't seem to factor into the equation. Has NASA even tried to actualize a fission rocket, just to test the waters? Just how bad can the protest be in face of hard scientific fact? After all, the Cassini launch had greenies protesting too, but when I saw it on the news, it was something like a few dozen people outside the gates. Is that all that's stopping NASA? A bunch of doped out hippies camping outside a barbed-wire fence manned by armed security guards? I hope not...

Re:It seems we really are afraid of fear itself!

[KillerBob]

I might not agree that this message should have been modded "Troll", but did you read the article that the message made reference to?

A fission rocket is a simple and safe system that uses a nuclear reactor to heat up a liquid such as hydrogen to create thrust. Unfortunately, "nuclear" and "fission" have been dirty words in this country for the last three decades. Despite the fact that nuclear propulsion is the best and safest way to fly major missions beyond Earth orbit, NASA stopped its development back in 1972 to put nearly every penny it had into the development of the shuttle. That was a terrible decision. At that point we had successfully tested nuclear rockets in the open air in Nevada, engines that could be operated with high thrusts for long durations--the key to entering the solar system.

Hippies slightly right

[leonbrooks]

While I agree completely with you about...

Idiot hippy environmentalists [who] speak of cutting dependence on (foreign) oil by moving to electric cars.

...as if electric power were magicked out of the air. It turns out that they're right about the GM plants but for mostly the wrong reasons. GM agriculture is running into all kinds of problems including - tahdahh - lower yields. It's a research cul-de-sac so far.

Re:Hippies slightly right

[the_consumer]

...as if electric power were magicked out of the air.

Magic has nothing to do with it.

Quote from link:
"The Australian Ecogeneration Association believes that wind could contribute at least 2,950 gigawatt hours of electricity out of the 9,500 gigawatt hours MRET target. The Association has stated that the MRET target should be increased to 21,400 gigawatt hours a year by 2010, with wind capable of contributing more than 10,000 gigawatt hours. "

Misguided

[Anonymous Coward]

How many failed chemical rocket launches would it take to make Florida uninhabitable?

How many failed nuclear launches?

Remotely possible

[leonbrooks]

I don't think anywhere is really "remote", unless one just means from themselves.

Got it in one. )-:

Say what?

[leonbrooks]

he argues based on a need (energy) rather than talking about exploration and science for its own sake.

No wonder nobody else replied - you mentioned a factor that was actually important. (-:

Solar power, wind power and stuff is nice, but the bottom line is there cannot possibly be enough of it even for our current needs even if we coated the entire countryside with collectors - so we need some new source of energy.

We ain't getting it here on Earth, so the obvious answer is...

Re:Say what?

[sgage]

"Solar power, wind power and stuff is nice, but the bottom line is there cannot possibly be enough of it even for our current needs even if we coated the entire countryside with collectors"

Well, my neighbor seems to supply all the electricity he and his family need from 3 rather small photovoltaic panels.

Plus there is still a lot of room for improved efficiencies of things electric.

So your premise seems a little exaggerated.

Re:Say what?

[ryanwright]

there cannot possibly be enough of it even for our current needs even if we coated the entire countryside with collector

BS. If the shingles on my roof were all replaced with small solar cells, it would generate many times more electricity than I use now. I calculated that I would need to cover only one quarter to one third of my roof with cells to more than satisfy my electrical needs and allow for some future expansion.

If every roof shingle in the nation was an individual collector, we would have tons of excess energy. Power plants could go away for good, we wouldn't need them. The problem is cost: To satisfy my electrical needs, I need to cough up close to $75k to buy the equipment. Now, that could be reduced significantly by switching to a gas range & dryer, and I could lose another $15k if I shut my servers off, but the point is it's expensive as hell.

The technology is more than adequate. The price simply needs to come way down.

Re:Say what?

[Anonymous Coward]

If every roof shingle in the nation was an individual collector, we would have tons of excess energy. Power plants could go away for good, we wouldn't need them.

Oy! A Californian! This might be great for you, but what about those of us who live in parts of the country where it snows 4 months out of the year? I'm not looking forward to climbing on my roof in the middle of the night to shovel it off so I can get my heat and lights.

Re:Say what?

[leonbrooks]

my neighbor seems to supply all the electricity he and his family need from 3 rather small photovoltaic panels.

His panels, house, car, refrigerator, the road outside his house and so on were not built using solar power (there is one solar panel factory actually run mostly using solar panels). The shops he buys food aren't standalone solar, nor is the service station (`gas station' to Nordamericanos) he fuels up at. And so on. And he doesn't run an airconditioner, spa or chest freezer off those panels, either, does he?

Re:Say what?

[leonbrooks]

I'm not looking forward to climbing on my roof in the middle of the night to shovel it off so I can get my heat and lights.

You wouldn't need to very often. In order to collect enough power, your roof would have to be nearly vertical, and huge... er, sorry, northern neighbour... and pity those in (e.g.) Novosibirsk.

Oh, you mean like this one?

[leonbrooks]

let's all live on Mars where it's lush, there exists eternal peace, and natural disasters are unheard of...

On Barsoom, maybe, but not here.

Scientists willing to let humanity bear all risks?

[Alex Reynolds]

The problem with any nuclear propulsion system is its imperfect design, by its nature, leaving a small, but non-zero chance of explosion or other incident that would dump a quantity of isotopes and heavy metal particulates into the atmosphere.

The higher these contaminants go (up to about 35 km, where air starts to dissipate), the larger the geographic area over which these contaminants will eventually spread.

Call it tree-hugging if you will, but I am critical of letting a large chunk of the human race bear the consequences of scientific failure.

At least with Hickam's arctic explorers, those fellows who perished didn't take down the rest of the species with them. The mission was risky, but to a small group of men.

The risk of this kind of mission is simply too great for rational consideration.

A smarter, less risky idea would be to reach the moon via safer means, and mine its surface for compounds needed to propel us to further destinations.

nuclear rockets were never meant for planetside

[Anonymous Coward]

The whole idea of the use of fission rockets is to move the ship around the solar system, between planets. You still must use chemical rockets for planetside work. Fission rockets work by using the megawatts of ELECTRICTY generated by the reactor to:
1)power the ship
2)power the shields (use coils to deflect alpha, beta, (etc)particles)
3)provide thrust along the lines of the recently proven ion drive, or superheat H2 and expell it like a chemical rocket, and keep the o2 for the astronauts.
4)allow 100x more payload to be shipped around.
5)waste? ship it to the biggest nuclear reactor in the solar system => the sun.

I have yet to see a suggestion by nasa to use nuclear "rockets" to lift off from earth. Never have, never will.

Nuclear energy for a long time?

[lohen]

Perhaps, but I'm hoping that habits will change pretty soon. If you look at the ever-growing effectiveness of renewables, there's real reason to hope for a genuinely clean solution. Even at present tech, Germany gets 50% of its energy from them, and they (particularly wind turbines) are getting cheaper and better all the time.

Long term, though, I'm still hoping for fusion. Between that and fuel cells, we could (theoretically) use massive amounts of energy while only endangering ourselves a fraction as much as we do today.

Re:Nuclear energy for a long time?

[praedor]

Ah yes, the bird-killing wind turbines. You want all the open space possible to be packed with migratory bird-killing wind turbines? Instead of looking out over a beautiful, majestic rolling plain or valley, seeing trees and rolling meadows you sell 150 ft white towers with the bodies of dead birds scattered about their bases.

Wind can play a big part of Germany's energy plans because Germany is small, doesn't have much left by way of wide open space that needs protecting. The US is, of course, huge with lots of space that should be protected from development before it is wrecked with structures and roads. The US is also more energy-intensive (Germany doesn't have any deserts where air conditioning 24 hrs a day (ok, in the dry desert areas swamp coolers are a more intelligent choice) for a significant portion of the year is a requirement. It doesn't have hot, incredibly humid areas like Louisiana where air conditioning is necessary to both cool and reduce humidity in the home. Germany doesn't have some 250 million people.

It is VERY possible to create inherently safe reactors that CANNOT, NO MATTER WHAT, meltdown. It is VERY possible to reduce the radioactive waste significantly AND safely encase it in "glass" for long-term storage such that it can't enter the water systems no matter what. If you do what France does, you end up with waste that has a max halflife of only a couple hundred years instead of thousands of years like we produce. You use fast breeder reactors that produce their own fuel and you refine the waste to recycle the useable fuel - this leaves you with minor, short halflife waste that is useless for making weapons and can be safely stored without worrying about ancestors a thousand years hence stumbling upon it. By then it will be long inert.

Once again, the Pavlovian knee-jerk reaction occurs with any sentence that contains the "n" word in it. Unthinking, emotional-not-logical-or-reasoned response. Nuclear power is a bigger part of our energy future, NOT a smaller part. That is a fact of life. We are not going to ever go back to some never-existent agrarian lifestyle where all was peaceful and quiet and perfectly clean of all waste. Fact of life.

Re:Nuclear energy for a long time?

[Anonymous Coward]

Two things... first, breeder reactors can create excess ammounts of new nuclear fuels... the 60 year guess you made is actually around 170 years at current levels and not accounting for breeders.

Two, turbines are not entirely efficient, but only knee jerk tree huggers are going to go off about birds laying scatter around dead. Typical.

A better solution howerever is massive fields of solar panels, created by small, self replicating robots, built in the deserts of the world. It is estimated that if you covered the Sahara with todays best efficiency solar panels, you could power all but a few corners of the world from the power for many generations. They would also have the effect of offsetting our wonderful greenhouse gasses since the best ones are black or blue in color and absorb heat and sunlight.

Re:Nuclear energy for a long time?

[praedor]

Deserts are fragile ECOSYSTEMS. They are not wastelands open for complete exploitation. Covering fragile deserts with solar arrays is not any better than covering most openspace with wind turbines. There is a place for each type of technology but it is NOT OK to eliminate desert ecosystems, great plains ecosystems, etc, so that miles and miles of turbines or collectors can be built (and the access roads and other infrastructure necessary to maintain and use them).

Killing migratory birds IS a big deal, by the way. People like to claim how benign solar collectors and wind turbines are but ignore the fact that it takes a LOT of them and it consumes openspace and wildlife habitat and kills wildlife.

Answer? You build a little of each INCLUDING reactors and dump oil/coal-fired powerplants entirely.

Nuclear Rockets eh and acceleration.

[gorehog]

Interesting....

Except for the fact that hickman discusses "constant velocity". I think he means constant acceleration. To attain a constant velocity you mostly just have to burn some propellant and coast.

Unless, and can anyone confirm this, he's thinking of "drag" created by gravity, magnetic clouds, etc, etc....

I have always been opposed to fission as a propulsive force because it was explained to me as a series of bombs going off behind the ship. This always seemed dangerous and dirty to me. This design though seems realistic, simple opening the turbine loop of a standard nuclear reactor. Seems like it could be as safe as the average nuclear sub, combined with the average space shot. Better launch 'em in the desert. Vandenburg seems like a real good idea again.

My question is this....

Since we're talking about constant powered flight can we also talk about constant powered flight at 9.8 m/s^2? This seems to me like the best solution for problems of bone and muscle deterioration. Just build the ship as a big platform, or stack of platforms at right angles to the direction of thrust. I know someone's gonna suggest a big spinning wheel, but there is a problem if the bearing seizes, the whole ship will spin.

Eh, more food for thought.

Check your facts!!!

[BigTom]

look at http://www.solarbuzz.com/FastFactsGermany.htm

It's stats are:

German Energy and Electricity Industry German domestic energy sources in 1998 were:
Coal: 46%,
Nuclear power: 31%,
Natural Gas: 14%,
Renewable Energy: 6%
Oil: 3%.
In consumption terms, though, oil accounted for 44%

Remarkably shallow and trivial op-ed piece

[mshurpik]

Let's do some research on this opinion piece and see how deep it actually goes.

Americans love rockets, and their interest focuses on the two ends: the front end where the astronauts sit and the tail end where the rocket engines are bolted. For decades, NASA has kept the focus on the front end through an unrelenting public relations campaign touting the astronauts' importance. While this is understandable, it has unfortunately resulted in a skewed program where the Space Shuttle and the International Space Station--both based on old technology--get most of NASA's budget.

1. Human space flight gets slightly less than half of NASA's budget. Read the budget yourself at ftp://ftp.hq.nasa.gov/pub/pao/budget/2002/budget_s ummary.pdf
(Note: Slashdot malforms the url. Remove the space in "summary")

It's time to seriously work on the tail end again and build advanced propulsion systems. If we don't, space endeavors will be stuck forever in low-Earth orbit, doing no better than struggling to bolt together the space station.

2. When the Voyager spacecraft made it to Neptune in 1989, was that in low earth orbit, or was that not a space endeavor?

The station is supposed to provide information needed before sending humans on long space voyages, but we already know that living in space is essentially bad for people. It is debilitating to bones and muscles, and radiation from the solar wind and cosmic rays can cause cancer.

3. I doubt that cancer will stop a two-year mission to mars. I *think* he's trying to bash on the space station, but it's not clear how. If I were the author, I would bring up actual, logistical problems like food and psychological stress - which would bolster the argument for a faster trip.

Zubrin writes:

"...more propulsive DV is added....at a significant cost to the mission in terms of reduced delivered payload. Such payload reductions do not merely reduce mission capability, they are a source of risk to the crew, as they imply the thinning out of redundancy of backups to various mission-critical propulsion, control, and life-support systems. The failure of any one of these systems would represent a much more deadly threat to the crew than the roughly 1% statistical incidence of cancer caused by a year of exposure to interplanetary levels of cosmic radiation. Thus if crew safety is the objective, attempts to accelerate conjunction trajectories beyond certain limits must be seen to be misconceived."

http://www.nw.net/mars/docs/nearterm.txt

To go to Mars or back to the moon with slow, low-powered chemical rocket systems is asking for trouble. The best a chemical rocket can do is get up to speed (burning up all its propellant in the process) and then drift to its destination, like a car coasting down the highway with its engine off. What's needed are space drives that will provide a constant velocity.

4. As already mentioned, he means "constant acceleration," not "constant velocity." Pretty big typo for an article on rockets.

5. It's not clear why going to Mars, and especially the moon, is asking for trouble with chemical rockets. A chemical rocket manned mission was accomplished in 1969 - over 30 years ago. In fact, if I recall, they made several trips and nobody died.

6. Zubrin examines nuclear rockets for Mars travel, and while he envisions using them for certain legs of the journey, the argument is expressed in terms of cargo capacity - not time savings. In fact,

"...It can be seen that the use of NTR [nuclear rockets] for TMI [Earth-orbit launch] is highly advantageous, increasing the delivered payload by 77% for cargo and 100% for piloted flights. However, it can also be seen that NTR offers no significant advantage over chemical propulsion for Mars orbital capture. This is because the large dry mass of the NTR stage combined with the large amounts of hydrogen propellant boiloff during trans-Mars cruise (even a H2/O2 chemical stage is only 14% hydrogen, NTR propellant is 100% hydrogen) destroys any performance advantage resulting from the high specific impulse of NTR when applied to a modest DV. This logic holds even more forcefully for the trans-Earth injection burn, which occurs 2 years into the mission and is much more conveniently accomplished by a space storable CH4/O2 stage."

I think what he's saying is that by the time you got to Mars and wanted to brake, a lot of your hydrogen propellant will have evaporated during the trip. Zubrin is favorable towards nuclear rockets in general, but his conclusions with regards to Mars are to use NTR only for post-launch acceleration towards Mars.

In short, the engineering of a Mars mission is so complex that the choice of propulsion system is but one of myriad factors involved in its success.

After Norway's Roald Amundsen and Britain's Robert Scott both reached the Pole in 1911 (with Scott's party all perishing on the way back), interest waned in duplicating their feats; it was far too expensive in both money and blood to do something that had already been done. Four decades went by before the next explorers arrived at the pole. They were Americans, and they simply flew there in an airplane.

6. Actually, Scott made it to the South Pole in January of 1912, and Americans flew over the pole in 1928. Just factual errors, nothing to worry about.

A fission rocket is a simple and safe system that uses a nuclear reactor to heat up a liquid such as hydrogen to create thrust. Unfortunately, "nuclear" and "fission" have been dirty words in this country for the last three decades. Despite the fact that nuclear propulsion is the best and safest way to fly major missions beyond Earth orbit, NASA stopped its development back in 1972 to put nearly every penny it had into the development of the shuttle. That was a terrible decision. At that point we had successfully tested nuclear rockets in the open air in Nevada, engines that could be operated with high thrusts for long durations--the key to entering the solar system.

7. It's not clear that nuclear rockets have been simple, safe, or successful at all. The Federation of American Scientists has this to say about NASA's nuclear test program:

"No fuel element geometry or fuel material ever totally solved the NERVA fuel element degredation problem. Mass loss of both uranium and carbon continued to limit service life by causing significant perturbation to core neutronics during the tests. Crack development in the fuel element coating was never compleatly eliminated.... Non-nuclear testing of coated fuel elements revealed an Arrhenius relationship between diffusion and temperature. For every 205 K increase in temperature (in the range 2400 to 2700 K), the mass loss increased by a factor of ten... resulting in loss of 20% of total uranium in approximately 5 hours of testing at 2870 K."

As for testing in the open air over Nevada,

"The major obstacle to testing at NTS will be the reduced levels of radioactive debris which are allowed to transport into the public domain. The levels are more stringent than those present during the NERVA program. The current exposure limits of 150 m Rem to civilian personnel may restrict the tests of the NTR to low power levels and mass flows in the reactor... A simple solution to this problem may be to utilize one of the Pacific Ocean Islands owned by the United States -- namely Johnston Island... (an) ecological desert of ocean surrounds the area due to the stagnation of the return of the Japanese current..."

So it seems we terminated the program because we decided to stop releasing radiation into the atmosphere - hardly a radical environmental concept.

http://www.fas.org/nuke/space/c04rover.htm

It's time to resurrect the nuclear rocket and confront the critics of nuclear energy, one of the cleanest forms of energy known. Hundreds of nuclear reactors are tooling around in the world's oceans right now, propelling submarines and aircraft carriers. Newer designs, including SAFE--the Safe, Affordable Fission Engine--are now being developed at NASA's Marshall Space Flight Center in Huntsville, AL.

8. Clean? Let's start with safety, which is, IMHO, a prerequisite for cleanliness. At Brown's Ferry, Alabama in 1975, workers caused a fire and near-meltdown by using a candle as part of routine maintenance. Workers caused a fission chain-reaction at Tokaimura, Japan in 1999 by pouring the wrong amount of uranium into a purification vessel. Chernobyl caused the relocation of 326,000 people.

http://power.about.com/cs/accidents/index.htm

To conclude, nuclear reactors are delicate systems with multiple single-points-of-failure and represent ecological SPOF's themselves. As for explicit cleanliness,

"At least 50 nuclear weapons lie on the ocean bottom due to U.S. and Soviet accidents....The U.S. Department of Energy spends over $4 billion each year for the restoration and management of sites contaminated by nuclear materials....Much of this is largely maintained, decommissioned, managed, and remediated by the EM program, which is sometimes referred to as the "cleanup program." EM's responsibilities include facilities and sites in 30 states and one territory, and occupy an area equal to that of Rhode Island and Delaware combined - or about 2.1 million acres."

http://lutins.org/nukes.html

But why send humans beyond low-Earth orbit at all? One word: energy. The low energy costs Americans currently enjoy are due to the abundant supply of fossil fuels. When those eventually go away--and they will--our advanced society may well collapse, unless we take the steps to prepare alternative energy sources. Wind, geothermal, tidal and solar energy resources can be added to the mix, but they will never supplant fossil fuel energy. For that we need something big. Only a combination of nuclear and space-based energy resources can ever take the place of fossil fuels.

9. Solar energy has been powering the earth for 5 billion years. I don't see any reason why our civilization should let itself outgrow that supply. As for fossil fuels, an article (not opinion piece) in the same magazine indicates that natural gas in the deep ocean may last hundreds, thousands, or even tens of thousands of years.

http://www.techreview.com/articles/voss0102.asp

The solar system is filled with energy in a variety of forms, including solar energy, which could be microwaved back to Earth, and the isotope known as helium-3, which happens to cover the moon. Helium-3 may be the key to fusion energy; many energy researchers believe that fusing helium-3 with deuterium is the cleanest and cheapest approach to commercial fusion power.

10. Yes, and in order to acquire more solar energy, we need advanced propulsion systems to set up collectors further out in the solar system.

Nuff said.

Re:Remarkably shallow and trivial op-ed piece

[ivan256]

I know you typed for a long time, but what exactly are you trying to say here. You seem to agree and disagree with this article, and you provide a myriad of incorrect facts to "back up" your "point". For example:

A chemical rocket manned mission was accomplished in 1969 - over 30 years ago. In fact, if I recall, they made several trips and nobody died.

Actually, three people died, and we almost lost three more.

8. Clean? Let's start with safety, which is, IMHO, a prerequisite for cleanliness. At...

Here you compare an absolute with a relative descriptor. Just because something isn't completely clean doesn't mean it isn't the cleanest thing available.

Also, you compare everything he says with what Zubrin thinks. Now I'm not saying that Zubrin is flat out wrong, but he hasn't sent any more people to mars then the rest of us. His ideas and opinions are no more then that, simply ideas and opinions. He is definatly one to admit that the problem is too complex to solve all at once. Even he doesn't know if he's right. You can't write off what anyone else says about getting to mars because it's not the same as what Zubrin said. There's likely more than one way to do it.

Then at the end you say: Yes, and in order to acquire more solar energy, we need advanced propulsion systems to set up collectors further out in the solar system.
So, are you for or against nuclear propultion? Do you agree with the author dispite all the 'flaws' you found in his article, or disagree?

Re: about overbreeding, and stupidity.

[guybarr]

A common indian women was asked "how many children will you have ?"

she said:
"I've had 4 kids, 3 already died, I want to have about 10, and I expect 2 to survive"

this is a very rational probablistic view, not a stupid women at all.

the indians as a nation ARE stupid, since they allow the situation to reach this point, but the "common" people are usually not stupid when it concerns their own survival, or they wouldn't be so common.

and wether you like it or not, it IS your problem, since hungry people bite harder.

(note I don't say sending rice or whatever is a solution, I believe technological and political methods must be used jointly, with threat of force when needed, but in any case, it IS your problem)

Do you drive a car?

[Anonymous Coward]

I don't see how it's legitimate for a small group of people to make the decision to risk every one else's lives, no matter how small the risk.

Do you drive a car? If so, you're putting other people's lives at risk every day. Think about all the pedestrians who are killed by cars every year, a depressing proportion of whom are little kids. Cars are one HELL of a lot riskier than any U.S.-designed nuclear technology (I make no claims about ex-Soviet stuff), yet people accept the risk without even thinking about it.

You saw it first ...

[Anonymous Coward]

on se

http://www.sensibleerection.com/entry.php/1072

Our options have been greatly reduced.

[Orangedog_on_crack]

It is clear that we will never do anything useful on the moon or mars if the only way to get there is the Saturn V.

I don't think the Saturn V is a realistic option any longer. Don't get me wrong. That beast is an absolute wonder of engineering, but we would have an excruciatingly hard time building any more of them. There are over 1,000,000 moving parts in a Saturn V. The last I heard, no one has any hard copies of the complete blue prints, many of the old computer tapes with those files have been lost, damaged, or have degraded beyond recovery. The majority of the parts manufactures no longer exist and almost all of the original engineers and scientists who designed it have died over the past 30 years. The only way to build another one would be to reverse engineer one of the surviving Saturn V's that were built but never used after the Apollo project was cancelled. One is on display in Florida, another one is also on display in Texas. I believe there is also a third that is in pieces in a couple of different storage facillities. I do wish they still built and launched these monsters. I'd love to see one launch in person.

Temp sig: "I just send the rockets up. I don't care where they come down, that's not my department." says Werner Von Braun.

Nope

[pgpckt]

If you were to keep burning fuel, you would keep accelerating (assuming an infinite amount of fuel) which anybody will tell you is not a good thing when you eventually want to stop.

Don't see why I should respect you when you think Newton's laws are still absolute. Einstein, as you may recall, debunked your statement by saying even if you keep accelerating, you cannot pass the speed of light. Your acceleration therefore cannot be constant at a constant burn rate, but changes as you start going fast enough for time and space to show the effects of relativity.

Send it into orbit? You and what army?!

[dscottj]

The problem with launching nuclear waste into space is that the stuff is heavy. Remember, it's made out of stuff higher than lead on the periodic table. We still measure the cost of launching stuff in the tens-of-thousands-of-dollars (US) per pound. You just can't put enough of it into space with one of today's rockets.

If you could get it up there cheap, then there's no better place for it. Send it on a collision course with the sun, and you'll never hear from it again.

It's just getting it up there that's the problem.

Re:Send it into orbit? You and what army?!

[mpe]

The problem with launching nuclear waste into space is that the stuff is heavy. Remember, it's made out of stuff higher than lead on the periodic table.

Except that fission products arn't transuranic elements.They are more likely to be from the Rubidium to Xenon row on the periodic table. Indeed if you were to get symetrical fission of Plutonium you'd get Silver. (As an unplesently radioactive isotope.) Heavy Strontium and Iodine are also common fission products.

Re: manual methods

[guybarr]

"A more likely case is it will be lifted by manual methods, piece by piece "

I'm not sure there's anything you can do by hand that will give a load that much delta-V .

Nuclear waste in space is a BAD idea.

[DoctorNathaniel]

Off-topic, but here's the big objection to this:

It could blow up. Say, where Challenger did.

In fact, it is just this problem which is important when considering nuclear-anything: what happens in the worst case? For modern, well-designed, ground-based reactors this isn't so bad. (Chernoble is NOT an example of a well-designed modern reactor.) Small reactors like on Subs have the advantage that even if they do crack open, they're (a) not very big, and (b) usually aren't near populated areas.

But if you have one of these babies crack open a few miles up, you can drop radioactive fallout over a pretty impressive area. I haven't looked at the case for the motor alone, but the waste is definately a bad idea.

Even if you got it INTO space, what then? Some more useless satilites to be a hazard to future spacecraft? Or do you want to actually get it into an escape tragectory? That's not nearly so easy as getting into LEO.

And.. it's expensive. Building one-shot rockets to move nuclear waste won't move very much.. and we make a lot of it.

---Nathaniel

Re:Nuclear waste in space is a BAD idea.

[Steveftoth]

According to a special I was watching on TLC, the reason that chernobyl melted down was that they were trying to generate power when it was unsafe. They knew that when they were doing it, but the Government pushed very hard on the engineers to generate as much power as possiable that saftey was not as large a concern as it should to have been.

Re:Nuclear waste in space is a BAD idea.

[AstroJetson]

This isn't quite right. They were operating the reactor near the edge of its performance envelope, but at the low end of its power range. This particular type of reactor is unstable when operated at low power. Then some safety systems failed when the core temp started to get too high. As is usually the case in large disasters, more than one unlikely event happened at the same time.

Herpes

[lohen]

Actually (and very OT), you'd have a good chance of being right if you accused those health nuts of having Herpes too - 60-90% of the world's population has been infected with Herpes Simplex Virus 1, and it tends to kick around in a latent form. Furthermore, you could also tell them that 1% of their genome consists of viral inserts, and that therefore they are a GMO (sorta), but they might not thank you for it.

Re:Herpes

[praedor]

Correct, for the most part. I was going to make your post. I would add a minor correction, however. The amount of the genome made up of viral-DNA is more in the low double digit percentage. If you count retrotransposable elements, VERY closely related to retroviruses (like LINE1 elements) the number of those alone is 17%. Throw in Alu elements, SINES, Ty elements...you are talking a not-insignificant portion of the genome.

ObHomer Jokes

[sharkey]

Mmmmm, fission.
Noo-cue-lar, it's pronounced noo-cue-lar.
I guess I do have the Right..., what's that Stuff?
Ooohhh, isn't there anything faster than a microwave?

Re:ObHomer Jokes

[Anonymous Coward]

the only thing faster than microwave is me running to the bathroom after my wife has been using the microwave.

How to stop it?

[tandr]

And how you gonna stop this damn 0.9 C thing if you don't have a second laser on the "other" side ?

"Slow down!!! this star is only 20 minutes away!"
"We ain't have any breaks, Sir."
"Oops."

Re:How to stop it?

[zeno_2]

Hmm.. I think I remember that there were going to be 2 sails, and when it wanted to slow down, it would release one sail and make it so the craft has a sail going in front of it, and one trailing it. The laser would bounce off of the leading sail, and get reflected onto the trailing sail, thus slowing it down.

Now if it will work I have no idea. Seems hokey to me, but I dont know much about this stuff..

Remember Cassini

[Smilodon]

Considering the overblown protesting over the Cassini mission a few years back, I have little belief that the public will even allow controlled experimentation with such technology.

Cassini was well within any reasonable person's definition of "safe". The most dangerous portion was the solid rocket motors of the Titan rocket that launched it. It was a tried system that was used in the Apollo missions (yes, radioactivity in Apollo! Horrors!).

I think all that is being asked in this admittedly PR-ish piece, is that some more money be spent on experimenting with alternative "in space" propulsion systems. Deep Space 1 was a perfect example, but let's stop doing it on a shoestring. We can't do anything until we explore some possibilities.

Science has been so successful in the past that experimentation has been translated to "implementing on a large scale world-wide". Space propulsion systems actually have little to do with power sources inside the earth's atmosphere (nuke plants), bombs or radioactive waste. Although, the benefits of experimentation with space systems might be applied to them.

I agree with previous posters that we need to find our power sources "out there" or "in route", but this may be a good stop-gap measure (and has been in the past, although more as a battery than propulsion).

Smilodon
V V

Can't blame 'em...

[Grendel Drago]

You can't blame them... I mean, remember the gross misinformation promulgated in the fifties? "Of course the government has your well-being in its best interests!"

I'd feel justified in being a little skeptic of any claims The Man makes about nuclear power. (Or about anything else, come to think of it...)

--grendel drago

Careful with the methanol claims

[Anonymous Coward]

GM corn is probably the most economically feasible way, at this point, to make large quantities of methanol, which could replace gasoline very easily, simply retrofitting existing vehicles and infrastructur

I've read a study that the net energy expended in growing (fertilizing, tilling) the corn and then cracking the hydrocarbons to form methanol is actually greater than the energy yield from burning the methanol.

Sorry, I don't have links, but as you pointed out, there's a lot of idiocy in energy politics, and this may have been one 'solution' that got pushed through on politics without a hard look at the whole product cycle.

Afaik Raps or Hemp oil into Diesel is better from the energy standpoint. Diesels can also be extremely clean (see the new peugot engine).

sorry for not having more hard data.

NMR also has unfortunate homonym

[rjrjr]

At my commencement way back in the '80s, one the speakers was an eminent Korean researcher (name escapes me) who spoke a lot about NMR--which his accent rendered "Enema." Needless to say, I don't remember much else of what he said.

Dihydrous Monoxide

[Vortran]

I love to expound to people on the horrors of dihydrous monoxide, explaining how many people are killed by it every year, how common it is, etc.. etc.

...then watch the look on their faces when I explain what it is.

Ignorance != bliss

We just launched Cassini...

[RumGunner]

And it had a nuclear decay generator.

Perhaps cooler heads DO prevail.

Here's some links.

http://www.bessereweltlinks.de/english/book44h.h tm

Dirty and Expensive and Short Lived

[Anonymous Coward]

I don't think fission rockets are the ideal solution. We should skip them (we know how to build them and the general mechanics behind them) and concentrate on more energy efficient and cleaner propulsion. It's almost as bad of an idea as pocket nuke propulsion IMHO, and even more daring an engineering feat for minimal return in terms of end velocity.

First off, everyone in the space industry that has their sights beyond our own orbital boundary really needs to get off the idea of building large ships and drives inside our gravity well. This work has to be done in a low or zero g envronment. That means we need to get our butts to the moon and build stations at la-grange that are not merely scientific outposts for waving the flag, but actually working space construction yards, factories, and living quarters for training and building.

Our greatest problem for orbital stations is intitial costs and a few minor technological elements we have not addressed yet, especially in medical science:
1) Costs are hugely high. This is because this is still a handbuilt, custom industry. It needs to be commercialized, just like PC's were in the 80's. The first PC's were hugely expensive because of their rarity and lack of overall demand... now they are as cheap as some more expensive PDAs.

You have got to put the technology we have developed and built to use on a large scale. There has to be a design revelation that dispenses with the expensive design qualities of very fine tolerances and puts in sturdiness and reliable redundancy in it's place. Christ, a single simple module on the ISS costs billions, but if you built it to work in our gravity well with off the shelf technologies and parts it would be 1/10 that.

Materials are present and exist, but are currently expensive to make due to the same lack of demand. These materials could be used to make the stations more 'bullet proof', while modern manufacturing could reduce costs overall. You just have to build the lines, ala AMD's effort to build their last FAB in germany...

In other words, reduce cost by building more.

To increase demand though you have to have some reason. They are zero-g crystal and chip manufacturing, bio-medical manufacturing, advanced research, entertainment (hotels... nothing like a zero-g night of bliss on your honemoon!), and mining (either going out to get easily retrieved exotics from asteroids or towing one back to orbit... both would pay handsomely over the initial investment in equipment, training, and technology).

2) You have got to get the physiological and psychological elements sorted out for low-g and zero-g environments and how they impact human physiology. There have been alot of studies, some announced counter drugs to bone loss and fluid loss, and research on how to keep healthy. There still needs to be some research on the psychology of space and how it effects people too. These have got to be a priority if humans are to exist in space until we devise some form of artificial gravity other than centrifical spinning of ship elements (which is a mechancial and energy nightmare, but one we must do at first until we find an alternative method of producing a gravitic field).

The other item to address is propulsion / energy. These two are very inter-related so you really can't say one without meaning the other in some way. Fision is just not viable. Shielding is very heavy, fuel is rather exotic and expensive, and the dangers of accidents and other technical glitches too hard to eliminate or discount.

Excited Ion is a method. Low fuel cost and weight, easily refueled from a broad range of gases available in space or around gas giants. Engines are not too technically expensive or difficult, but the power to weight ratio is relatively low. They are efficient and clean however, but certainly not enough to climb out of a gravity well like ours.

Fusion or Fusion Plasma is another. The creation of fusion power should be our 'short term goal' here on earth. The creation of these powersources, especially if their size can be minimalized brings us to the age of clean fuels and power, with the ratio of cost of fuel to output power (figuring in construction costs of the power source) to a point where it is 'cheap power. An excited plasma torch can then be coupled to this to create a relatively clean booster that can technically accelerate an object to very high speeds over a long run (upwards of .5c)

Anti-Gravity would be great. There is some research in the rather exotic field in physics centered on wave theories and graviton particles. This is probably a long way off, though quantum computers would certainly speed up the calculations end of this. I truely lean towards the existing theories that gravity is not only a nuclear force, but a wave/particle similar to light but in such a excited state we have yet to detect it or generate it knowingly. I expect that artifical gravity is possible, but at extreme power costs for generation and control.

Anti-matter would be the best. Well duh. We are making steps here, if only baby steps, in the past decade and especially in the past three years. We understand the principals and math, the physics of it all, and are pretty sure now that we can, at huge power expense, generate the particles we are interested in and contain them. I think that AM is tied in with fusion in alot of ways as it will take great amounts of cheap power to generate AM and store it for use as a reaction fuel... but boy what a fuel it would make.

In fact, if we were to discover a cheap way to generate, store, and use AM overnight, we couldn't use it right now for manned flights at it's full potential because our physiology just won't withstand the forces of acceleration it is capable of... it would be a crippled technology until we could somehow dampen inertia or control gravity.

But, you could theoretically build a ship that could get you to Saturn in back in less than a month in system, and give .9c or better for interstellar flight.

Ultimately we need to look towards finding a shortcut around einstien and the theoretical limit barrier of 1c. This may come in the form of energy tranferance/transmission or dimensional control allowing us to move in a straight line through the dimmensional curve of space/time. Instead of 10-20 years to the nearest star, 10-20 minutes should be 'long term' goal of humanity.

We have got to get off this rock we call Earth. We are inquisitive by nature, divided amoung ourselves because we all seek our own perfect version of life and avoid our innate primal fear of the unknown in each other, and we are wasting away in on a single point of life that is one big target for mass extinction should some otherwordly or political fate befall us. With the driving force of exploration, commerce, and establishing new worlds humanity could work together and put behind some of the oddities that make us great and doom us at the same time.

Heinlein's "Torch" ships

[PopeFelix]

This sounds exactly like Heinlein's "Torch" ships in "Time for the Stars," published 1956, and some of his subsequent work. I liked the idea then, and I liked the idea now. Space is chock-full of radiation, relatively speaking, so irradiating a bit more near-vacuum shouldn't be a problem, should it?

My Point

[Aglassis]

My point was that Uranium is not radioactive as a fuel until fission begins in the reactor section of the rocket. Until fission begins Uranium is just as dangerous as any other heavy metal. You can spread it around all you want and it will not increase the risk of cancer (unless by some chemical property).

But once you start up the reactor section, the uranium doesn't make it radioactive, its the fission products, the transuranics (typically things like plutonium transmuted from uranium due to neutron absorption and subsequent beta decay if I remember correctly), and the activated metals in the housing of the reactor section. If you chemically seperated the uranium left over afterwards it would still not be radioactive.

And since there is no reason to start the nuclear section of the rocket on the earth (think multiple stages with chemical sections getting it into orbit), the reactor will not be started, hence no radioactivity until its safely in orbit. If it crashes and burns, its no bigger deal than heavy metals contaminating the environment.

Re:Fission? He's GOT to be kidding!

[Anonymous Coward]

Not that we have anything even equivalent to the Saturn V these days.

Accidents? So what!

[jafac]

So what about a few tens of thousands of people getting leukemia over the next 20 years. I wanna go to Mars now!

Nuclear Not The Only Option

[hotsauce]

Wind, geothermal, tidal and solar energy resources can be added to the mix, but they will never supplant fossil fuel energy. For that we need something big.

One can try to make fun of people for being suspicious of nuclear power, but this guy is at the other end of the spectrum. "We need something big"? Solar power and the sun aint big enough for you? Tides and the oceans aren't big enough for you? We abolutely /must/ rush out and mine the moon for fusion power?

This guy has a (theoretical) solution in search of a problem. He threatens the end of civilization when fossil fuels run out if we don't mine the stars. Let me guess, he used to write grant proposals for NASA.

Re: Bad Idea, here's why-- here is an idea

[Brigadier]

Here is a thought, use conventional measures to get to say the moon, or a space station then use nuclear power to go beyond. somewhat like the movie event horizons. It used conventional measures to go to the outer limits of teh solar system. then used its "gravity drive"

A few comments on breeder reactors

[mbessey]

Breeder reactors can refine most if not all radioactive waste from fission reactors and reduce their radiactivity back to normal ground levels, thus allowing them to simply be buried. Some waste can be refined and re-enriched enough to be re-used via a breeder reactor as well.

Um, no. Breeder reactors do very little to address the nuclear waste issue. The big "advantage" of the breeder is that it transmutes U-238 (the most common isotope of Uranium) into Plutonium. This has the effect of reducing the cost of fission power, since you get a lot more useful fuel out of each ton of Uranium ore you mine. In general, breeder reactors produce more highly-radioactive waste than "conventional" fission reactors because of the higher neutron flux.

Fast breeder reactors also have a much lower safety factor than other reactor designs. They're more susceptible to small losses of cooling ability than other reactors. The safety record of breeder reactors in the US is not particularly encouraging, either.

-Mark

Re:Fission? He's GOT to be kidding!

[Anonymous Coward]

The reactor shielding required for a manned spacecraft is pretty large. There isn't any particular mass savings through using a nuclear power source... most of the mass for a deep space mission is reaction mass, and the specific impulse developed by a nuclear rocket is only about 2 times that of a chemical rocket...

That's true if you use 19th Century technology for energy conversion and propulsion, but if you use an ion engine then you get a *much* higher specific impulse. It's true that the thrust would be nothing to write home about, but for a long trip it would be much better than anthing we could do with chemical fuels. The only real challenge to a nuclear rocket would be a solar powered rocket, again using something more efficient than a heat it up and let it expand type of engine.

Now, if someone could finally get fusion rockets to work, I think we could finally go someplace.

That would probably still be heavy and require shielding, and I'm not sure that the luddites would be any happier with it. But I would be willing to ride either a fission or fusion vessel to the asteroid belt if I were in shape and young enough. In the long run, if we don't go there we're dog food.

Yes it is full of rocket fuel.

[Edmund Blackadder]

I dont think he or anybody else is seriously suggesting using a nuclear reactor engine to get off the ground. That cannot be done safely. Readiation shields are too heavy, and the exhust will be more than "slitly radioactive", and a lot of it will be released very close to the ground. What he is suggesting is using the nuclear engine in space, so yes there will be plenty of rocket fuel while the rocket is leaving the earth. So an explosion is almost certain if the whole thing hits the ground. Even if the rocket manages to separate its rocket fuel before crashing, having so much radioactive material crash at high speed is just not safe. A nuclear rocket engine will not be low pressure. Its true current nuclear reactors are, but the rocket engine cannot be if it is to fullfill its promise of high efficiency. The whole idea of "a nuclear engine is more efficient than a conventional engine" rests on the fact that a nuclear engine should be able to shoot off water vapors at a much higher speed.

Re: about overbreeding, and stupidity.

[ivan256]

and wether you like it or not, it IS your problem, since hungry people bite harder.

As long as people like that continue to refuse considering a cultural change as a meaningful option, then it is their problem. If millions die out of stuborness then I don't see how it can be anyone's fault but their own.

Re:Fission? He's GOT to be kidding!

[sketerpot]

It truly annoys me that we can spend so much money on nuclear weapons, soldiers, stealth airplanes, and such, and yet NASA and the schools have budget problems. Space exploration has brought us a lot of great stuff and taught us many things. I still think that if we want to fight terrorism we should seek a truly permanent solution, rather than just killing a bunch of people.

The permanent solution I'm talking about is worldwide education and prosperity. Once people are happy and well educated, most of them won't feel like running planes into buildings. Space exploration is a long term investment, just like education. But it seems that few people care about potential to solve problems forever, they just think what the media and politicians and the people next door have told them to think. If people in the middle ages had thought for themselves, they wouldn't have let the Church rule over them and torture heretics. Now I don't think we'll have a repeat performance.

Why can't we look for answers to our problems, instead of just throwing bombs at them?

Si-Fi and reality

[Alehandro]

Antimater, warp-drive, antigravity busters or plasma engines or ionic drives. Unfortunatly they are not realistic. Most of them a fictional rest are not effective. Nuklear powered rockets are only way to go. Eather old fashion 50's 60's or the way americans are trying to do. You may say what about plasma. Well what will power the plasma drive?. We just don't have yet anything more powerfull then nuke. The only way to power plasma drive is a nuklear reactor. Well if someone will make warp drive to power plasma drive. That will be great, but for now:( End of cold war killed all researches in this filed. There no more competition, no more being the first. Now insted of exploring mars and europa we will better bomb someone.

advanced nasa studies funded

[techtrends]

The current president and VP are the most receptive leaders to nuclear power that we have seen. But large scale use of nuclear power in space is still not likely for the US. China maybe ?

However, there are many interesting ideas for improved propulsion that are being funded and prototypes are being produced for some ideas that are doable with todays technology.

Quick summary:
-Most of the better ideas involve solar and magnetic sails and beamed power. Some also use solar gravity assist maneuvers.
-many interesting methods for making beamed power to achieve significant .1c possible with more achievable lasers (200MW) and sub-km size optics
-magnetic sails can break against the solar wind of a target star.
-close gravity slingshots to the sun, carbon-carbon shields to within 1.4Million km (4 solar radii), would provide speed boost of 100km/s.
-Any deep space probe needs to use radioactive power sources

To see some studies of what is being considered as possible breakthroughs check out :
http://www.niac.usra.edu/studies/study_master.j sp? action=Advanced_Propulsion&rsnum=null&lastDisp=nul l

The most promising near term possibility is
M2P2. (It has cost less than $1M to demo the a system in the lab and could be Space Technology mission 7 for the New Millenium missions - less than $200M and within 3 yrs.) The M2P2 system utilizes low energy plasma to inflate a magnetic field beyond the typical scale lengths that can be supported by a standard solenoid magnetic field coil. In space, the inflated magnetic field can be used to reflect high-speed (400 - 1000 km/s) solar wind particles to attain unprecedented acceleration for power input of only a few kW, which can be achieved by solar electric units. Initial estimates for a minimum system could provide a typical thrust of about 3 Newton continuous (0.6 MW of continuous power, from intercepted solar wind), with a specific impulse of 10K to 100K seconds) to produce an increase in speed of about 30 km/s in a period of 3 months. Proposed optimization could allow the development of a system that increases the acceleration level obtained with less expenditure of fuel. The optimized system could enable a mission that would leave the solar system.

They have working prototypes in the lab. The follow on systems would likely use a nuclear power source to maintain the magnetic field for multi-year durations and acceleration to 1000km/s. Plus

Hoppy Price, manager of solar sail tech development at NASA's Jet Propulsion Laboratory, sits on a committee that evaluates technology proposals for New Millennium missions.
"It's a neat concept," he said of M2P2. "It has a lot of potential but it's also very early in the research phase."
"Most of the solar sail technologies we are looking at now are at tech readiness level four, which means we have some laboratory demonstrations of the technology," he said. M2P2 is at a lower level of readiness for the moment, he said, although fast development of prototypes and testing could make it available for use in some of the approaching New Millennium missions, such as Space Technology 7.
http://www.niac.usra.edu/studies/study_master. jsp? action=Advanced_Propulsion&rsnum=null&lastDisp=nul l
http://www.space.com/businesstechnology/technol ogy /m2p2_winglee_010621.html

Here we go again

[Mandelbrute]

Nuclear power is the only viable solution.

OK - arguments for nuclear power.

Cheap - look at the example of British Nuclear Fuels, where there are less subsidies than the US situation. How many billions do you think they have lost? All those rare earths used in nuclear components are not cheap.

Clean - Learn some chemistry or physics. Advertising will not make it clean - only careful research which has not yet been done (it's a pity the advertising money didn't go into research instead, but the advertising obviously worked on those that are now young adults).

Coal, Oil or Lime flavoured jelly is more radioactive than released wastes - This is actually quite true is you consider the total amount of the coal, oil or jelly that is used each year, the only thing is that the radioactive materials are so spread out to be completely harmless (particularly in the jelly) and are of a different type to those in high grade nuclear waste. We are talking about amounts of radiation too small to measure on an unconcentrated sample (gravity seperation can concentrate it more). Remember, some background radiation comes from the rocks beneath our feet. Ten million tonnes of coal is always going to be more radioactive than a barium enema, but the coal is somewhat spread out and there are worse wastes produced from nuclear power plants than those that are used for comparison in their advertising material.

No carbon dioxide emissions - A good reason. Personally I don't think it is a good enough reason. Nuclear power is not likely to ever happen in the country I live in anyway. There are no plans for a nuclear weapons program, so there is no economic reason to have it.

Nuclear rockets are a different issue - we're not talking about just boiling water here. Some people protest loudly whenever they hear the word nuclear (like in the case of the cassini probe, where risks were minimal and possible consequnces small). Each design will have to be looked at on it's merits. People also protest loudly and not listen to reason because of all of the lies in the past - to the extent that some people will not beleive anyone with a technical background, because they lump us in with 1980's tobacco industry medical researchers.

Three Mile Island ... caused by imbeciles

Wasn't the verdict criminal negligence? Aren't the plants still built and inspected by the lowest bidder with "self-assessment" instead of real checks and balances? I would be very happy to hear otherwise. If not, the imbeciles still have seats in congress.

Combine With Space Elevator

[Anonymous Coward]

This would be perfect to use with a space elevator. Existing earthbound Plutionium in storage for decay can be converted to fuel for such an engine (whats a fast breeder use again? Plutionium, Lithium and L*) to buzz around the solar system, it's so radioactive in space it does'nt matter. Clean up and put the waste to practicle use - that's gotta be a win win situation for the atomic industry.

Probably not a good idea for a launch vehicle, I do not like the idea of one of these things coming down, and then there is the introduction of volume radioactivity into the atmosphere, yes yes use helium.

Sure we need to reduce our reliance on oil, but unless the oil companies are interested both of these concepts will be mired in politics. I think though there would be a great demand for oil products in space though Mr oil company win for them too.

Finally an established presence in space mean we increase the human races redundancy and we can beam energy to earth - where it is needed. Controlling energy/resources has always been where conflicts start.

Re:Hippies still slightly right

[leonbrooks]

The Australian Ecogeneration Association believes that wind could contribute at least 2,950 gigawatt hours of electricity out of the 9,500 gigawatt hours MRET target. The Association has stated that the MRET target should be increased to 21,400 gigawatt hours a year by 2010, with wind capable of contributing more than 10,000 gigawatt hours.

Yes, there is a windfarm at home, but even the enthusiastic Cailfornian windfarms won't make anything like enough for half of California's power demands (which was the topic of discussion), and this is the usual case. Australia is fortunate in having enormous amounts of (mostly uninhabitable) land to plonk windmills down on.

Take two

[leonbrooks]

If the shingles on my roof were all replaced with small solar cells, it would generate many times more electricity than I use now.

By golly, you were singularly fortunate to have a skillion roof optimally aligned for your latitude!

How does it manage to track the sun? How does it arrange to collect most of its power in winter and just after sunset, when it's nost needed? How often do you wash down your roof? What is your average annual cloud cover?

Does your energy budget include storage and conversion losses? What kind of cells did you model? Does it also account for the manufactured (`inherent' or `embodied') energy in your house, furniture, fencing, solar power system, car (and propulsion thereof), street etc?

I could lose another $15k if I shut my servers off

Or ran the right MIPS boxes with no luxury items like video cards. You can just about power those from a hand-cranked flywheel.

You'd likely save more than that by replacing your existing refrigerator with an efficient DC-motor chest 'fridge.

Mass budget

[leonbrooks]

FriendlyHal 9000 [v2.0 ...] sends out a small, self contained machine (small I mean a few thousand tons).

...lofted at stupendous cost from Earth and still working after over 400 years in transit... `tap, tap, is this thing on...'? (-:

Re: about overbreeding, and stupidity.

[guybarr]

you misunderstood what I specificly wrote.

I did not discuss fault or morals, just pragmatics.

pragmatically, billions of hungry people, many of them with goverments with (or soon to be with)
nuclear weapons are a large military risk.

the overbreeding of the poor nations is not just a societal disaster for them, and an ecological menace to the world, it also leads to very bitter wars (like in africa), and as you americans noticed this 11,9 , homocidal maniacs hurt you as well.

if it can kill you => it is your problem.

Silly man

[Anonymous Coward]

"the bearing siezes"

LOL!

Hint: There is no bearing. You don't need a bearing.

Silly silly

Remarkably shallow and trivial follow-up

[mshurpik]

You seem to agree and disagree with this article, and you provide a myriad of incorrect facts to "back up" your "point".

OK so a "myriad" is two. Also, you didn't disprove my points...read on. I like how you used quotation marks, you seem very clever.


Actually, three people died, and we almost lost three more.

Nobody died in transit! And I know about Apollo 13, I saw the movie.


Here you compare an absolute with a relative descriptor. Just because something isn't completely clean doesn't mean it isn't the cleanest thing available.

Right. And nuclear energy is certainly cleaner than solar and wind power. What rock did you crawl out from under?


Also, you compare everything he says with what Zubrin thinks.

No, I compared *two* things he said with what Zubrin thinks. Once again, 2=myriad apparently.


Then at the end you say: Yes, and in order to acquire more solar energy, we need advanced propulsion systems to set up collectors further out in the solar system. So, are you for or against nuclear propultion?

God, you are such a wanker. Why would we want to collect solar energy *further away* from the sun?


Do you agree with the author dispite all the 'flaws' you found in his article, or disagree?

Why does it matter? I don't have a position for or arainst nuclear rockets. I have a position against the accuracy of Homer Hickham's information.

Sorry for the hostility, but I figured that if you could respond to my post without doing any research - or even reading it - I could respond to yours without being nice. You fucking fag.

Re:Hippies still slightly right

[the_consumer]

Australia is fortunate in having enormous amounts of (mostly uninhabitable) land to plonk windmills down on.

We have that here in the USA, too. Well, the land is habitable, but not too many people live there. There's a huge wind corridoor running from Utah through Kansas, on land which is mainly either farmed, ranched, or state-owned. There are ranchers negotiating wind-rights deal with energy producers all over the place. They get piad to lease their wind rights, we get the energy, and they can still ranch (cattle don't seem to mind windmills). And CAs windfarms are showing their age, coming close to 30 years old now. Wind generation tech has come a long way since then. Then there is the intriguing possiblity of photoelectric plastics which could be cheaply made and used nearly everywhere. What if the vinyl siding on your house produced energy from the sun? Could happen soon...