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Update on Project Prometheus
Aglassis writes "It appears that NASA is not backing down from their nuclear space initiative. Project Prometheus has recently started a new web page (under JPL) and NASA is finishing up a period of public comment (last session today). Currently Northrop Grumman is contracted to begin preliminary design of the spacecraft until 2008 for NASA (the reactor will be built by the Department of Energy's Division of Naval Reactors--the folks who control all US submarine and aircraft carrier nuclear reactors). Early specs are that it will be 60 meters long, have a 30,000 kg mass, use a 100 KW reactor using Brayton cycle gas turbines, be powered by ion thrusters with a 7000 second specific impulse, and have a science payload of 1500 kg. Early mission plans for Prometheus 1 (Jupiter Icy Moons Orbiter) indicate that the spacecraft would orbit Callisto, Ganymede, and Europa individually, and perhaps have a lifespan of about 20 years."
Disclaimer: I am not a rocket scientist.
In Soviet Rush, today's Tom Sawyer gets high on you.
For a large space and aviation company- just awarded a $400 million contract- you'd think they could afford to hire a copy editor.
:)
That was terrible. Cool project though
Thats right the Asgard, come and install their own warp engine
So they finally figured out how to stabilize naquandria...
Actually, funding for JIMO (Jupiter Icy Moons Orbiter) has been cut.
Finally, we can make some real space vehicles. Fission is the most energy dense technology we have.. it's what we should be using in space. When fusion comes along we may well have something better, but until then we should use what we have.
How we know is more important than what we know.
Wow. Am I the only one that thought the JPL must be some license agreement like the GPL, and the wondered why the hell a web page needed to be released with a special license?
Jet Propulsion Labratory
Portland, North Dakota Puppies
"Does it run Linux?" ... yes, it does. The onboard microcontrollers on the craft will run the uCLinux kernel, with Gentoo userspace. I have no idea what the boxen back at NASA supporting this will run though.
... I for one don't want to welcome our angry alien overlords after they get sick of the crashes :-)
It's a pleasant thought that the first software that aliens might encounter from Earth won't be from M$
"Prometheus Nuclear Systems and Technology will focus on enabling NASA missions by researching and developing nuclear sources that will provide power to innovative scientific instruments and robotic systems, large and small propulsion systems that run on electricity and high-speed communications systems. The nuclear power sources would allow us to extensively explore our closest celestial neighbor, the Moon, as well as Mars and other destinations. Eventually, these power sources would support human explorers as they travel through space and explore other worlds.
= mi ssions
The first proposed mission within Prometheus Nuclear Systems and Technology would be a mission to Jupiter, the Jupiter Icy Moons Orbiter (JIMO), which represents a new class of mission capabilities far beyond those possible with current power and propulsion systems. Powered by a space nuclear reactor and propelled by electric ion engines, the spacecraft would make up-close, long-term orbiting visits to three of the solar system's most intriguing moons- Europa, Ganymede, and Callisto. Beneath their icy surfaces, these moons may contain oceans of water that could have provided an environment that may have harbored life."
http://prometheus.jpl.nasa.gov/index.cfm?pageL1
Beats the heck out of me what that has to do with militarizing space. Besides, IMO, nuclear power is a lot less environmentally dangerous than other power sources except maybe solar energy (which might not work when you're x billion miles from the sun).
--- Grow a pair, liberals... stop letting the Republicans bully you!
Is a possible reason for NASA avoiding nuclear propulsion that the U.S. is worried about giving other countries yet another reason to build nuclear reactors?
http://prometheus.jpl.nasa.gov/contentImages/Blimp _over_Titan211_br.jpg
If that above picture happens in my lifetime, I will drop a load.
I hope they start with something more resonable than this. A big project will get bloated and is less likely to happen. Instead of going to Jupiter, how about getting to Mars with a little more reliability, with people?
Rosco: "If brains were gunpowder, Enos couldn't blow his nose."
what do you think absorbs the readiation from the sun? (hint, its our atmosphere) that big ball in the sky that is the solar systems largest reactor (although its fusion, not fission). Honestly, do you think it's light that heats the earth? no, it radiation. Any radiation from a little spacecraft up in space is miniscule!
What are we going to do tonight Brain?
than the real progress NASA makes.
IMHO, it's a real shame projects like these aren't far more international in scope, open to all bidders, and funded from a futures type trust and traditional venture capital funding, as well as grants and taxes. Heck, most of these projects will pay back in spades if the new technologies were only properly licensed.
It simply amazes me how we have so many business geniuses, but not one of them has even considered space as the next new continent. What ever happened to good old American ingenuity and initiative, eh? Why have we apparently just given up our collective dreams of space exploration and development? Any one care to explain?
Words to men, as air to birds.
"It appears that NASA is not backing down from their nuclear space initiative."
It'll still be lifted off the ground by chemical rockets. What happened to NERVA?
Yeah cool but please don't call till the Agamemnon is launched.
Goofing around aside. This is cool. Dangerous but cool. Let's face it. This will be the mode of propulsion that will take spacecraft around our solar system for many years to come.
What could possibly go wrong?
We used it in WWII.
And Iran would be pacifist if we never got involved in their history. They had a moderate government with some elements of capitalism. But then the USA decided to help Hussien, we sold him all the arms he needed to attack Iran for over a decade. And we let the Shah get expelled, for a very rigid Kohmeni.
Rosco: "If brains were gunpowder, Enos couldn't blow his nose."
I don't know the ins and outs but I'd imagine that if you have a nice chirpy nuclear-reactor to generate power, taking photovoltaics (solar panels) with you too would be rather pointless. - PVs would cost extra to put into space to start with and would also need trickery to align them with the sun.
Having glanced at the picture, I'd suggest it is more likely that the big flat panels are heat dissipators (heat-sinks) to get rid of the excess heat from the nuclear reactor. I presume that in space there is no conduction of heat away from the vehicle, only radiation. And that you improve the radiation of heat by increasing the surface area.
Ripping an new rectum in the fabric of spacetime.
That's 10 times the best chemical engines ever designed.
Light is, of course, radiation.
There have been at least three Russian nuclear-powered RORSATs that have fallen to Earth, one into Canada in 1978.
Not sure how big the Russian satellites are compared to this, though.
Great. Let's just hope that the ships don't encounter the Minbari along the way ...
That said, I'm happy it never really materialized. Having a universe with a human population spreading effectively in it summons an eerie image on a spherically expanding brain-tumor to my mind...
http://isbndb.com/d/book/project_orion.html
Our local observatory (with live night-sky camera) is Gummint-funded. This leads to some interesting effects.
Much of their computing equipment has been scrounged - and doesn't appear on any equipment manifests - because there was no budget for it. They have a Pentium-90 driving (pointing) their main 'scope with a backup P-90 literally sitting on the next shelf in case it dies.
The few pieces of gear that they do get grants for are typically extremely fancy. On the rare occasions when ThePowersThatBe say "yes, you can have a computer to process the incoming images," then the cost of that actual computer system and absolutely nothing else is almost immaterial as long as it fits certain criteria.
So... in the room to the left of the one housing the P-90 sits a you-beauty glow-in-the-dark (well, not literally, it would cause backscatter) state-of-the-art box with double overhead ThermalTakes and all the trimmings. Just one. And I bet they crammed memory and disks into that baby's purchasing spec until the chassis groaned under the weight.
When Mark Shuttleworth gave his amazing talk at LCA2005, one of the things he mentioned was that the Yanks didn't want their astronauts (also going up in the Soyuz with Mark) flying to Baikonur in a rattly old Tupelov transport lest it unexpectedly drop out of the sky en route, but rather than come out and say so directly they came over all clever and simply pointed out that NASA regs forbade their astronauts to travel without seatbelts, which they knew the Tupelov wasn't fitted with. This was a mistake. On the day, the astronauts were marched out to the Tupelov, and aboard - and into a minibus in the cargo bay, where they sat and wore the minibus's seatbelts for the duration of the trip.
BTW, when the video DVD from LCA2005 gets published, bend heaven and earth to get yourself a copy. It's well worth-while for Mark's presentation alone ("Welcome to Khazakstan!"), and there are many other excellent presentations on it (Keith Packard explaining the sport of Window Hurling, for example, or E'dale demonstrating how to collapse a penguin's skull).
The point in that story which I wanted to use as an illustration here was that the minibus wasn't put aboard the transport for the astronauts' benefit. There was a budget for flying the Tupelov - pilots, fuel, landing fees and so on - but no budget for getting from the airport to where they were staying. So the van (which fell under the base's budget, so was financially covered) was fuelled up and driven aboard the Tupelov for use as a taxi while the transport 'plane was prepped for the return flight. In terms of working around bizarre regulations, NASA or not, the Americans really were amateurs playing in a professional field. (-:
Got time? Spend some of it coding or testing
Because this reactor will be designed to be in a rocket explosion. It will be launched before it goes critical. it wont even be turned on, and cant be turned on, until it is safely in orbit. Beyond that, there is alot more nuclear material in your nighborhood reactor than there will be in this thing.Not only that, but NASA launches over the ocean, water is a very good radiation shield. Thats why there are several nuclear submarines lying on the ocean floor that you arent worried about.
In case you didn't realize, Uranium is the 8th most common material on the planet... Taking a few tons off of it won't do any good. There's enough uranium to last the damn planet for the next 2000 years at least. Don't argue with me, I researched the damn thing two months ago. :)
Due to financial difficulties, the light at the end of the tunnel has been turned off.
I don't know where you live grozzie. But I do know that your world is better because of those US nuclear weapons built by us hypocritical pots.
Well atmosphere and the Van Allen belts which scoot much of the dangerous radiation around us (Earth).
Of course those outside of our atmosphere and Van Allen belts are exposed to massive amounts of radiation, and without protection they would die.
As to radiation from a Nuke in Space.
1. Nuclear reactors don't explode, to explode (i.e. nuclear bomb) requires particular materials in a very specific configuration. A reactor does not meet the requirements. What you would end up with is a large hot radioactive mass.
2. 100 Miles away wouldn't make much of a difference as there is nothing to stop the radiation in the interim (Vacuum of space), so you just loose exposure geometrically as the sphere of radiation expands. Regardless radiation exposure is kind of a binary system (for you geeks) enough to kill you is enough to kill you. Adding more does not kill you more. Since deep space has enough radiation to kill you the addition of more is irrelevant. Unless it is of a type to penetrate the shielding. That type is already emitted by the Sun, and is not particularly emitted in high numbers from runaway reactors.
As to putting massive amounts of radiation into space. Well we have the Sun which is a big massive nuclear reaction dumping huge amounts of radiation. The sun is 1 million times larger than the earth. Therefore any nuclear reaction we put into space by definition is going to be less than 1 millionth the size of the sun, as a reaction 1 millionth the size of the sun would be the size of the entire earth, and any nuclear mass we put up is going to be less than that. In fact it would be less than 1 millionth of 1 millionth the size of the sun. And this puny mass would be in the solar system which is even bigger than the sun (By definition) in fact it's a lot bigger than that, much much bigger. So long as it's outside of orbit of the earth and doesn't come crashing down on East Philadelphia it would be of so little significance it wouldn't matter.
But regardless. whether it's buried in the ground of Gabon, or floating in space it's just a matter of position. It's still floating around in space, and still emitting radiation. Putting it on a deep space probe just moves it from one plce to another.
are you implying that a 100kw fission reactor in orbit presents an exposure concern to personnel? i hope you are joking. assuming average prompt gamma ray energy is 1 Mev, the reactor has NO shielding, 1 Ci of a 1 MeV gamma ray point source produces an exposure rate of 1R/hr at a distance of 1M, all of the energy is emitted from a point source, and the reactor acts as a 100,000 Ci point source(this should be conservative, someone with more knowledge might upgrade me on this?), then(neglecting backscatter buildup): DR @ 1m = 100,000R/hr DR @ 10m = 1000R/hr DR @ 1km = 0.1R/hr DR @ 100km = .01mR/hr
365 days * 24hr * .01mR/hr = 87.6 mRem(assuming 1 as a QF, i can't recall the QF for a 1MeV gamma flux right now).
assume the reactor and craft present 1 tenth thickness of shielding(should be conservative): 8.76mrem
assume the atmosphere presents 3 tenth thickness of shielding(again conservative): .00876 mRem
this craft in orbit(realizing it will not remain there) would, conservatively, increase the average persons natural radiation exposure by less than one thousandth of one percent.
this is simplistic but AFAIK conservative.
Second of all, a propulsion system has little to do with interstellar travel. Even if this thing worked (it's designed to stay in the solar system), we would still be unable to travel to other solar systems. The problems of time, distance, and physics as we understand them will almost certainly keep us in this solar system forever.
Thirdly, I think you underestimate the immediacy and gravity of the problems facing us. Making it through the looming problems of global warming, fossil fuel depletion, overpopulation, terrorism, et al has to come before bankrolling the research of private technology interests--which is all this really amounts to in the first place. If Northop Grumman wants to pursue this technology and they can do it safely, let them do it. But our economy already stands on the verge of collapse. Are we supposed to suddenly believe that the organization that lacks the funding to complete the Voyager project now suddenly has the money to undertake this much more expensive mission? Are we supposed to assume they have the competence, after two shuttle explosions and a backwards mirror in a multibillion dollar telescope, not to detonate the reactor in the atmosphere? I want my tax dollars going to more practical use, and so should we all--unless we hold stock in the contractors behind this massive scam, the same sort of people who keep insisting we need a missile shield in this world of suitcase bombs.
We aren't getting off this rock anytime soon, regardless, so we might as well try to buy a few more years here until we have the technology to terraform and settle Mars. That technology will emerge without pointless exercises in lunar exploration.
(%i1) factor(777353);
(%o1) 777353
Embedded systems use a device called a watchdog timer. Basically, it counts down from, say 2 minutes, then reboots the computer. The programs running on the computer need to continually reset the timer back to the 2 minute mark. If the computer locks up, the timer is never reset. It will count all the way down and reboot the computer.
"I'm not impatient. I just hate waiting." - My Dad
I thought you might like to know that nucleotides are those cool little thingies in your DNA that make up the genetic code.
The current plan is for fission reactors to be used outside of an earth orbit. Earth is close enough to the sun that solar panels are still a good choice for energy, so reactors aren't needed. It's on the deep space probes, like the Jupiter Ice Moons Orbiter (if it ever happens) where this becomes useful. It could also potentially be used on a manned Mars mission since the extra power it produces could be used to run an ion propulsion system.
dude.. exploring the solar system sets us up to learn how to traverse space!!! how the fuck do you think we are going to figure out how to go to other solar systems if we do not figure out how to safely travel in out solar system?
where the fuck would we be if some cave man said he was not going to let any other caveman go anywhere until they figured out a way to travel 30 miles a day? we would be no where!!!!
practice makes perfect dumbass!!!!
I am the Alpha and the Omega-3
The image was done in LightWave 5 roundabout 1996-1997. The Omega cruiser was done by Matt Stetson, and the Starfury mesh was done by Mark Kane. LightWave was the same program used to do the show as well.
Oh yes, and I know this because I created that image. :)
My old site with a bunch of Babylon 5 renders is still up, although much of it was lost several years back.
#1 - Not immediately no. The technology that is developed to do this is of significant value to future attempts at living in other environments - or space.
#2 - This propulsion system has everything to do with getting us to planets within our solar system. Up until the announcement of this project we have had chemical rockets to push us around the solar system. They are not suited to prolonged flights. This development is exceedingly important for getting us to destinations outside of lunar orbit.
#3 Consider your words more carefully. But our economy already stands on the verge of collapse. This is not, in anyway a true statement. It's an alarmist over exaggeration of what's going on. Things have a way of sorting themselves out when it comes to the economy. Given the level of data available and the fact that people are managing the markets on a day to day basis - a "collapse" is not likely.
As far as threats to the world:
Global Warming - perhaps by the end of this century this will become a problem. The reality is that it's not just a U.S. problem - thus it's not truly "fixable". Fixing global warming has very little to do with money and everything to do with policy. As far as events that pose a threat to humanity this is certainly one - however a migration to say mars, could be realistic within the time frame of this event actually causing a great deal of trouble for us.
Overpopulation is another interesting one. Did you know that densely populated areas are showing a decline in the birth to death ratio? That is more people are dying than being born. The evidence is starting to indicate that at least in urban areas populations are self limiting. Good news. Obviously this doesn't help in Africa where there just isn't enough food, and no contraception available. Again with global warming - the U.S. throwing money at this problem isn't going to fix anything.
Terrorism? How is that an immediate threat? Yes, it's a concern but as far as having the ability to destroy our civilization. Terrorism is at its worst a "new" form of combat, that isn't liked by those (G8) who play by "rules". Either way - it's not going to bring down the house. Money might help this problem - but I'm not sure that it's any more important than ensuring we (humans) survive.
The one thing that you touched on that has some validity is fossil fuel depletion. Depending on how badly the Saudis have depleted their oil fields (no one really knows) - the next 30 years could be very rough. The overarching problem with "Fossil Fuels" is not the fossil fuels but the lack of innovation in energy technology. Ideally the replacement for oil is a combination of Fusion and Hydrogen. We might have to suffice with Nuclear and Hydrogen, but the world needs to start now - and from what I can tell that is not happening. Wind, Solar, Tidal is great but it's not going to supply heavy industry with the regular and massive amount of power that is needed to run our economy. Money might actually help here - but we're not spending it.
I want my tax dollars going to more practical use, and so should we all
Who are you to tell us what we should endeavor to do with our tax dollars? In reality - "tax dollars" and actual budgets have very little in common.
Are we supposed to suddenly believe that the organization that lacks the funding to complete the Voyager project now suddenly has the money to undertake this much more expensive mission?
No my friend, they lack the desire. If they wanted to save it - they would. Apparently, like you they want to stay focused on projects that have immediate value. Those are missions within our solar system. The Great Unknown and what we could learn from it seems to be less attractive. As far as I can tell the probe is expected to continue transmitting until the 2030's but there seems to be no reference to the actual "mission" lifetime. The probes have both completed their primary mission and it would seem are fair game for discontinuation.
Nuclear fuel from a high altitude spacecraft explosion (side note, what would explode anyways?) would be spread out over an area of a square metre or two at most, as it will be in a container that can survive re-entry and crash landing, much as the "black boxes" that survive airplane crashes.
"I'm not impatient. I just hate waiting." - My Dad
On a related note, a few words about nuclear rockets. Back in the 50s and 60s some people, mostly science fiction writers, fantasized about nuclear powered rockets. In the 60s there was an actual prototype engine called NERVA. The idea was simply to use the reactor as a heat source to superheat a gas which would shoot out as rocket exhaust. The main drawbacks were the weight of the reactor core, the maximum temperature of about 3500 degrees C, and the radioactivity of the exhaust.
Here's a really interesting article that describes a design for a 100% reusable, non-polluting nuclear rocket based on the Saturn V form factor, capable of lifting 2 million pounds of cargo into orbit and returning to a soft landing. Just like in the old sci-fi movies. The design involves a gaseous core reactor, sometimes called a "nuclear lightbulb." It consists of a quartz bulb containing a cloud of uranium gas such as uranium hexafluoride, confined the center of the bulb by a buffer gas swirling around it. By adjusting the movement and pressure of the buffer gas, the compression of the UF6 can be finely regulated. When it is compressed to a critical state it heats up to about 25,000 degrees C, glowing intensely in the ultraviolet. Liquid hydrogen propellant pumped around the outside of the quartz bulb absorbs the ultraviolet light, becomes superheated, and shoots out of the nozzle. There is no leakage of radioactive fuel and no irradiation of the hydrogen. Completely clean burning. Such a rocket could burn for immensely longer times than any chemical rocket, providing the speed to get a manned mission to mars in a couple months. And not a skimpy mission, a spacious vehicle carrying 1000 tons of equipment, supplies and radiation shielding. Building a rocket like this wouldn't require any far-fetched technology, just some dedicated engineering.
I have never been a fan of nuclear reactors, but this thing sounds really good to me. The gaseous core has tremendous safety advantages over a solid core. The criticality of a cloud of gas is much easier to control and is to some extent self-regulating. For example, the problem of "hot spots" would not exist, because in gaseous form any part of the UF6 that overheated would expand, losing pressure and quenching itself instantly. The author describes several safety features, both active and passive, for letting the gas depressurize into a storage container extremely fast. Even if a gas core nuclear rocket exploded in the atmosphere, it would release a small fraction of the amount of nuclides from a single 1950s H-bomb test.
that's right, George, there's rivers and rivers of LIQUID HYDROCARBONS down there, and America's got the mineral rights!
No, the correct answer is: the US is already a declared nuclear state and the continued manufacture of nuclear weapons is therefore not a violation of the Non-Proliferation Treaty, which pretty much says "If non-nuke states don't build their own bombs, nuke states will help them build reactors." What Iran is doing is outside the bounds of the treaty.
Besides, when you already have several thousand fusion warheads, why build more?
As an anti-nuke nut, I'd like to say that I'm fine with NASA using nuclear energy.
I'm just not fine with Haliburten using it.
While we're at it, why don't we shoot all the oil and coal and natural gas into space, too? After all, they're what power all those tanks and jet fighters that fight our wars...
How about all the steel in the world, too, to keep people from making knives?
Seriously--did you ever stop to think about the fact that nuclear fission might be a useful thing?
Some of us happen to think that nuclear fuels will help PREVENT wars over dwindling fossil fuel resources. Put that in your pipe and smoke it, hippie!
Hai. Arigatou gozaimasu, Aisanhawaa-sama.
Real Daleks don't climb stairs - they level the building.
And here, ladies and gentleman, is a shining example of the output of the US public school system!
Seriously, if you're going to bash the US, do it right:
Iran had something of a constitutional monarchy after WWII, with elected offices alongside a hereditary monarch. A certain Iranian politician was getting very popular, powerful, and friendly with domestic (and possibly foreign) communists. The US didn't like that and Teddy Roosevelt's grandson had the guy killed, whereby the hereditary shah took complete control, abandoning the democratic process.
Because we installed the shah, Iran was friendly.
Then the Iranian people, not happy with the lack of democracy and all, overthrew the shah and, doing what most other revolutions do, collapsed in on itself. After a few weeks/months the "Islamic republic" we all know and love came to be, complete with everybody's favorite ayatollah. Understandably, they weren't too friendly with the US. It wasn't that we "let the Shah get expelled" so much as we didn't keep propping him up, since some bad experiences in Cuba convinced Congress to rein in the CIA and keep them from doing the whole "overthrow a national government" thing again.
At around this same time, for unrelated reasons, some nut-job overthrows democratic government in Iraq on his own and installs himself as the country's dictator.
Iran didn't go against the US because we decided to support Hussein, we decided to support Hussein because Iran went against the US. You seem to have confused cause and effect there. In the beginning, there wasn't any clear moral high-ground in the Iran-Iraq War, and so we went to the next question on our Flow Chart of Foreign Policy*: "Which side is friendlier with the Soviets?" Things went (further) downhill from there.
"And Iran would be pacifist if we never got involved in their history."
... You're funny.
In general, if said government has human beings involved, it's not pacifist.
* It could have been worse. I suspect the Iranians currently use a Coin-Toss of Foreign Policy.
And Iran would be pacifist if we never got involved in their history. They had a moderate government with some elements of capitalism. But then the USA decided to help Hussien, we sold him all the arms he needed to attack Iran for over a decade. And we let the Shah get expelled, for a very rigid Kohmeni.
I think you are a bit confused about the particulars, though your general point is correct.
Act I: Iran has a popular, secular, western-educated leader, Mohammed Mossadegh. Unfortunately this leader happens to brush American and British governments the wrong way, to the point of actually nationalising local oil companies (shock ! horror !)
Obviously our luminaries of freedom and democracy can not tolerate such an attack on western businessmen's rights. So they organise a coup to get rid of Mossadegh and put the Shah into power, leading to a few years of a rather brutal dictatorship. That's Act II.
Act III: At some point the Iranians got really pissed about it and started a revolution. This revolution was driven by two main forces: socialist intellectuals and islamic fundamentalists. As soon as the Shah was overthrown, the islamists simply eliminated the socialists and used their fanaticised support base to crush upon any kind of dissent.
Just a bit later, Saddam launched a war against Iran for seemingly no reason - but with thorough US and western backing, at least in the beginning (hey, he's against the Mollahs, so he's a good guy, right ?). One million dead. Only when reports of atrocities emerged (gasing of Kurdish populations) did the west begin to reconsider their support for Saddam.
Iranians hate the US, period. But this deep resentment against America was not instillated by their government - only exploited as a way to strengthen their power (since the Iranian government is the most outspoken opponent of the US on the world stage, anyone who dissents with the Iranian government can conveniently be called an agent of the US). Iranians have good reasons to dislike the US. By removing a moderate, popular government from office out of short-term considerations, they opened the way for a much more brutal, oppressive and dangerous regime in the end.
You'd think they'd learn.
Thomas
We're missing an opportunity here. This isn't about nuclear space propulsion, this is about:
Permanently removing nuclear material from the Earth
Look at what a wonderful service is being provided, nuclear material is being made to Go Away Forever. The minor factor that it opens up exploration of the solar system is a minor side-effect, we don't need to talk about that. Just think of the nuclear material elimination aspects.
The hurdle is to convince skeptics that it's "Challenger-proof", not "Columbia-proof". Remember that this stuff is never intended to re-enter, only launch and leave, forever. From a materials durability point of view, that's quite a difference. Much more of Challenger was recovered than Columbia, and in better shape. That suggests that nuclear containment might well better survive a launch problem than a reentry one.
I don't know if this is meant as humor, or not.
The living have better things to do than to continue hating the dead.
It's much slower than traditional orbital transfers, but so much cheaper that it's worth using. It's already been used on SMART and Galileo:
http://www.sciencenews.org/articles/20050416/bob9. asp (even mentions using it for Jupiter moon exploration!)
http://www.ufoindia.org/news_intsuperhighway.htm
PHEM - party like it's 1997-2003!
The Soviets even reused RTGs salvaged from blown up missions because thay were in usable condition after plumeting from the sky and it was cheaper than building new ones. Any US designed nuclear reactor will be just as robust (unlike Topaz).
I am becoming gerund, destroyer of verbs.
"when you take a small mass of radioactive material that gives off lethal amounts of radiation and spread it over a large geographic area you cannot get a lethal exposure. "
It really doesn't work that way. Highly-radioactive chunks of metal of various sizes hit the ground after Cosmos 954 crashed. Several of them could have delivered a lethal dose to a person whio handled them without proper protection.
Here's one reference
And another reference
That talk about the potential lethality of some of the recovered fragments from the satellite. Keep in mind that nobody knows how many of the fragments that hit the ground were actually recovered.