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."

Comments

fp

[Anonymous Coward]

I WANT!

Northrop Grumman

[TrueJim]

It's spelled Northrop Grumman.

Brayton cycle

[worst_name_ever]

Interesting that they would pick a Brayton cycle power generation scheme. Since it's open-loop, that means you limit the lifetime of your vehicle to however much working mass - not reaction mass, that's probably xenon in this case - you have on board. Of course the limiting factor might in fact be reaction mass after all, in which case it actually makes sense to have an open-loop reactor and reap the benefits of a simpler system.

Disclaimer: I am not a rocket scientist.

Re:Brayton cycle

[Smidge204]

There are open and closed versions of the Brayton cycle engine.

=Smidge=

Re:Brayton cycle

[John Seminal]

Interesting that they would pick a Brayton cycle power generation scheme. Since it's open-loop, that means you limit the lifetime of your vehicle to however much working mass - not reaction mass, that's probably xenon in this case - you have on board. Of course the limiting factor might in fact be reaction mass after all, in which case it actually makes sense to have an open-loop reactor and reap the benefits of a simpler system.

Disclaimer: I am not a rocket scientist.

I am a rocket scientist, so I can anwser your questions. The key is to find planets rich in dylithium crystals. Or we can negotitate with other civilizations.

Seriously, with everything they will need to carry with them, I hope they find a power source that is plentiful everywhere.

And this is another reason why I hope we start colonizing other planets, building little self containted cities with mines and data reasearch centers. What will happen when the space ship runs out of fuel around pluto and nobody is there to help? I know.... it is all science fiction anyways. But maybe if someone can dream it, someone can build it.

Re:Brayton cycle

[Profane MuthaFucka]

They'll use hydrogen. Xenon is used for ION engines, not nukular engines.

Re:Brayton cycle

[B3ryllium]

... they said it would use ion thrusters, would those be using Xenon by any chance?

Re:Brayton cycle

[Anonymous Coward]

I prefer tachyon burst cycles. The inverted particle beams end up using excess energy from the recombinator to power the foodarackacycle AND the port-a-potty. GENIUS.

Re:Brayton cycle

[WindBourne]

I am a rocket scientist, so I can anwser your questions.

Cool, could you explain how you end an italics in HTML? Or how to spell answer?

For the humour challenged, Just kidding

Re:Brayton cycle

[Anonymous Coward]

Call this a nitpick, but Xenon is not nukular fuel. It's quite the opposite. NR is fond of nuke power the old fashioned way, with Fission. Xenon does not fission, it absorbs neutrons and beta decays radiantly.

Re:Brayton cycle

[NarrMaster]

...Xenon would be for the Ion thrusters there buddy.

Re:Brayton cycle

[worst_name_ever]

Oh - sure. Just run the working fluid through a heat exchanger and start all over again. See, I told you I'm not a rocket scientist! Hell, I'm just glad I even remembered what a Brayton cycle engine is - thermo class was a heck of a long time ago...

Re:Brayton cycle

[Short Circuit]

Disclaimer: I am not a rocket scientist.

Then get Moofie to weigh in!

Re:Brayton cycle

[TheKidWho]

He knows, but a baryton engine requires(this is what the grandparent assumed) a working fluid to get the heat energy of the nuclear reactor to power a turbine.

Re:Brayton cycle

[starman97]

Here's Nasa's close Brayton Cycle unit
http://www.grc.nasa.gov/WWW/RT2002/5000/5490 mason. html

Only 24% of the thermal heat from the reactor is converted to electricity, but then that's probably pretty good for a closed cycle unit.
No good heatsinks in space.

Re:Brayton cycle

[Profane MuthaFucka]

Yes, those would probably be Xenon. Other ion thrusters that have flown, such as Deep Space 1, used Xenon.

Re:Brayton cycle

[Fyz]

But maybe if someone can dream it, someone can build it.

Professor: "Nothing is imposible if you can imagine it. That's what being a scientist is all about!"
Qbert: "No, that's what being a magical elf is all about!"

Re:Brayton cycle

[Smidge204]

The inky blackness of space is a balmy 4 degrees Kelvin last I checked. You can get pretty good radiative heat transfer with that.

I'd say the limiting factor for efficiency is size. That's a pretty small turbine! If they were able to build it bigger they could increase efficiency quite a bit, but I'm guessing size (and weight) restrictions are preventing that...
=Smidge=

Re:Brayton cycle

[shimmin]

On the other hand, until you get further away from the earth, you're taking in 1000 W / m^2 on the side facing the sun, and you have to get rid of that, too. The Apollo missions landed at lunar dawn for a reason.

Re:Brayton cycle

[dpilot]

You get no "transfer" to that 4K, you just get to radiate into it. As the other response says, you also have solar radiation to contend with. So your radiator has to be mirrored on the sunward side and black on the outward side. As long as your outward side can radiate more than your sunward side absorbs, it's just a matter of scale.

Re:Brayton cycle

[StarRoamer]

I dunno, my understanding is that the reason they landed at dawn was to use the contrast from low-angle sunlight to be able to read the terrain in order to pick the best possible landing site. Don't want to put a landing jack in a hole or on top of a rock. Tip that sucker over and you ain't never goin home again.

If it was for thermal reasons, as you imply, shouldn't they have landed at sunset instead of dawn?

Re:Brayton cycle

[Retric]

IANAP but it seems like building an Insulated shade would work Better than just having a Mirror. 4 layers of foil sepearted by 1cm of vacume would cause the outer layer to heat up a lot more and thus radiate more energy.

Your also working in 3d space so if your radeator is a long tail then you get a lot of surface area to that space than you have with the sun.

AKA I would build something like this.

Insulator
V V
: | | | | Reactor | - Radiator
A
Mirror

Re:Brayton cycle

[dpilot]

Good point. Kind of like how Kirk beat Khan, because the latter was still too 2-dimensional in his thinking.

Extending the idea, it's worth keeping in mind that this thing will be forever a creature of deep space, and therefore may well make feasible novel construction methods that would never hack it in 1G. Take your 3D ideas and let them get thinner and bigger, as appropriate. Imagine, f'rinstance that on the dark side of the sunshade is a double-balloon, with the outer one black, to radiate. Have helium coolant flow between the inner and outer balloons and let the outer surface radiate. Not exactly the way I'd do it on Earth, but low-strength low-density construction may well make it reasonable.

Re:Brayton cycle

[Smidge204]

When energy (heat) goes from here to there, that's called a transfer. It doesn't really matter what it gets transferred to (call it "dark matter" if it helps).

As for solar gain, that's simple... position your radiator so that it's parallel with the sun's rays. Let the sunshine hit the edge of the radiator, which would have a much smaller profile and would not be part of the heat transfer surface. You could even build a small sheild or use the craft itself to create a shadow.
=Smidge=

Re:Brayton cycle

[uluhtc]

I believe that you are confusing conductive heat transfer with radiative heat transfer. Conduction does care about the medium (and the temperature of the medium) that surrounds it. Radiation does not. Since there isn't much of a medium to go around in space, conduction is practically non-existent and there is no need to take into account the average temperature of deep space.

Also, it might seem to make sense to point the radiators edge on to the Sun, but then why do you have radiators in the first place? Radiators of this size are required to dump the heat from a reactor. The reactor is there because solar cells can't be used. In other words you are too far from the Sun to have a significant amount of solar radiation input. A shield in this case would be extra weight and money for no real benefit.

Re:Brayton cycle

[Smidge204]

Um... well first, I do not believe I'm confusing conduction with radiation. When you look out into space, which is mostly but not entirely empty, you "see" what is effectively an average temperature of 4 degrees K. There is no conduction or convection, but there is a temperature difference between you and the surroundings which causes radiative heat transfer.

As for solar cells, everyone in this thread is assuming that the reactor would be used fairly near earth to get the thing going, as well as deep space. Deep space would not be a problem, I agree, but near earth would be. That's how the topic came up.
=Smidge=

Re:Brayton cycle

[uluhtc]

Okay, I see where the misconception lies now. The temperature difference between the radiator and the surrounding does not "cause" radiative heat transfer. As I mentioned before, a medium is not required for this type of heat transfer (hence the reason it is used in spacecraft). Even if the spacecraft was close to the sun it would radiate heat. The problem then would be that the radiative heat from the Sun would more than make up for that.
The main problem with flying with big radiators near-Earth will be drag, therefore, they will be nearly edge-on relative to the velocity vector. Then to avoid a big hit from solar radiation all that is required is a near-equatorial orbit. This type of orbit is almost certainly going to be used. A shield would only be needed if the main body of the spacecraft was going to take on a lot of heat--not really an issue unless the spacecraft will be going closer to the sun, say to Venus orbit.

Re:Brayton cycle

[Nutria]

Good point. Kind of like how Kirk beat Khan, because the latter was still too 2-dimensional in his thinking.

Any fighter pilot would know to think 3D.

As would a soldier/marine in urban combat.

As would even the captain of a ship.

Take your 3D ideas and let them get thinner and bigger, as appropriate.

Wouldn't enlarging the suface area raise the possibility of meteor damage?

Re:Brayton cycle

[Nutria]

But maybe if someone can dream it, someone can build it.

Professor: "Nothing is imposible if you can imagine it. That's what being a scientist is all about!"
Qbert: "No, that's what being a magical elf is all about!"


You missed the "maybe".

Re:Brayton cycle

[Smidge204]

No, the temperature difference DOES cause heat transfer. The only misconception here is that you're being a pedantic jackass. Perhaps if I inserted the word "net" in front of "radiative" you would be satisfied?

"net radiative heat transfer"

There, happy? For all intents and purposes, if two objects are the same temperature then there will be no heat transfer between them. You can argue until you turn blue in the face that they are trading energy through radiation, but it won't get you any points outside of a classroom. Heat transfers from hot things to cold things unless you do work to go the other way. No temperature difference, no transfer.

And just to cover my bases: "hot" and "cold", as used above, are relative to the absolute temperatures of the objects involved.

How is a radiator's drag going to be any worse than that of a solar panel?

An equatorial orbit would NOT be ideal, since the earth's axis is tilted. An ideal orbit would be in the same plane of the earth's (or whatever planet's) path around the sun. This would allow you to place the panels in the ideal position for both minimum drag (lowest profile along the velocity vector) and minimum solar insulation (lowest profile to sunlight).
=Smidge=

Re:Brayton cycle

[uluhtc]

Actually, I wasn't being a pendantic jackass, I was correcting something that was wrong. Period. Not just a subtle, technical issue that will only appear on an exam; plain wrong.

You can have net heat transfer from an object even with a hotter object nearby via radiation. A radiator will lose heat (via radiation) to space regardless of what it is near. It's ability to absorb/reflect will determine if there is any heat transfer the other way. You can't just simply say what the NET direction will be based on temperature. Only for conduction and convection can you say this...not radiation. What would be the purpose of a shield by the way if you couldn't take advantage of this fact?

Not that you will want to know since you seem to "know" it all ready... the orbital plane of the Earth about the Sun that you are referring to is called the ecliptic. Since I wasn't trying to be pedantic or overly technical, I just said that it was near-equatorial. There is really no need for it to be exactly in the ecliptic for simply for thermal reasons--it would be determined based on other constraints.

As for why drag is an issue here, the radiators needed are huge, as in on the order of 500 m^2. Not that it will slow it down, but it does make attitude control an issue if you try to fly it sideways.

Re:Brayton cycle

[Retric]

Wouldn't enlarge the surface area raise the possibility of meteor damage?

Yes, but there are many ways of dealing with this. If you're doing Deep space stuff then there is little Need to worry about hitting stuff, as there is not much to hit.

My idea would be to use a system that looked like leaf where you have a large heat conducting core that branches out a few times and then has a thin film between each of those braches so if something hit's a large brach the brach would survive and if it breaks a small part of the mesh then it's ok because you can make it 10% larger to start with and know that large chunks of it are not going to be damaged. (Looking at the base you would see an X as 2 2d leaves intersect at the central shaft. Now the large shafts should be able to withstand impacts from objects that where small and you just navigate around larger objects.

Amway, they need to radiate 100 KW (or 100 KW / 24% efficient > 400KW I don't really know what there numbers are.) From a 60 meters long 30,000 kg mass ship so it's really a question of how efferent it's going to be at radiating heat as to how much and of what design there cooling system needs to be.

PS: I always thought that the whole Kirk/Khan 3d thing was a little odd but even though some people really don't think well in 3d I think it was more a plot device than anything else. I suspect real space combat would be like submarine combat where you can hide by not moving (In space you could be moving but you can't change your speed or direction.) or scream out where your position is by moving but with the distances involved and the lack of a "top" speed there is not going to be much dog fighting.

Re:Brayton cycle

[shimmin]

At sunset, the moon is already hot, so your ability to radiate is impaired by the thermal radiation from the moon beneath you. And you have to leave before it gets dark, because then you can't see anything.

Re:Brayton cycle

[Noose For A Neck]

I do wish that they'd state whether that is thermal efficiency or second law (isentropic) efficiency.

The PDF is embarrassing

[bloggins02]

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 :)

Re:The PDF is embarrassing

[Anonymous Coward]

we can't be a wasting money on a copy editor! bypass the copy and the editor and just let it out! information wants to be free!

Oh great

[Anonymous Coward]

Yay, nukes in space. Aren't there treaties to stop this kind of madness?

Yet another example of how Washington wants to militarize space.

Re:Oh great

[Anonymous Coward]

You're an idiot.

Re:Oh great

[Travoltus]

"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.

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= mi ssions

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).

Re:Oh great

[Anonymous Coward]

I second that!

Re:Oh great

[CSMastermind]

There are treaties against testing nuclear weapons in space (Or did Bush pull the US out of those? I honestly can't remember). Nuclear fuels are a good choice due to the fact that the potential for use is greatly increased while the danger a mistake leading to an explosion is small and mostly not dangerous to us or anyone with the probe far out in space. This idea has been long proposed, it's nice to see it gaining momentum. And for the record, it would benifit everyone to colonize space. We already have missiles that launch from space (thanks to clinton) which Bush has already used...there's not really much more that could be done with the militarization of space.

Re:Oh great

[X0563511]

Not so dangerous? What exactly happens when a nuke is detonated in space? I know that there would be no pressure wave or firestorm, but there is no atmosphere or ground to absorb the radiation...

Re:Oh great

[Anonymous Coward]

URL to missles that launch from space?

Re:Oh great

[QuantumRiff]

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!

Re:Oh great

[John Seminal]

Not so dangerous? What exactly happens when a nuke is detonated in space? I know that there would be no pressure wave or firestorm, but there is no atmosphere or ground to absorb the radiation...

We don't know what would happen. There is a whole cluster of scientists who believe in SuperString Theory, that we have 10 dimensions but can only percieve 3 of them. Imagine a newspaper comic strip. That character exists in the X and Y plane. What happens if you fire something in Z plane? To him something will appear and disappear quickly. Kinda like how we percieve electrons?? So say we fire off that nuke, and in reality it sends some wave we can't percieve. And that wave hits something else which causes the nuclear action to continue. The whole universe could collapse on itself.

And in those final seconds, I can just hear Bush's voice "Trust me, I know what I'm doing".

Re:Oh great

[X0563511]

Well, I was thinking of a nuclear detonation (think meltdown but worse). And, you have a good point. I forgot about the sun :)

Re:Oh great

[Anonymous Coward]

me thinks sun is far worse than a nuke

Re:Oh great

[Anonymous Coward]

If that happens I'll eat my hat. I really doubt it will though.

Re:Oh great

[Bad D.N.A.]

We know exactly what would happen because we have already done it. http://www.phy6.org/Education/whtrap1.html

Re:Oh great

[complete loony]

But if there is a problem on take off, and the craft burns up in our atmosphere...
Not an insurmountable problem, the design of the engine will need to withstand an aborted take off and be launched over an unpopulated area like the sea.

Re:Oh great

[Profane MuthaFucka]

Oh damn, a nuke in space would turn it into a harsh environment that would kill a person quickly unless they were wearing a special protective suit! Can't let that happen.

Re:Oh great

[X0563511]

I would feel sorry for anyone in a space station or vehicle in the vicinity. The sun is a long way away. If a nuke detonated 30 miles from a space shuttle, I bet the crew would still have some serious radiation complications.

Re:Oh great

[grozzie2]

What exactly happens when a nuke is detonated in space?

Most of the immediate damage caused by a nuke, comes from the pressure wave from the blast. In space, no atmosphere, no pressure wave. So, the impact from the pressure wave doesn't exist, so not much is damaged immediately. The chain reaction also lets off a lot of heat, that would definitely effect things in the immediate vicinity, it may even melt them. There will be a localized concentration of radiation for a period, but, there's lots of various forms of radiation in space already, again, will only effect things that cant take it (electronics and such), have little effect on things that can (rocks et al).

This is why i laugh every time the issue of meteor impact comes up here on /., and various folks want to 'nuke it'. A large meteor on an impact trajectory with earth is not going to be affected much by a nuclear explosion, unless the device is detonated well below it's surface. Just landing on it and blowing up, without an atmosphere, isn't going to do much of anything. Blowing up 'in the vicinity' is just going to shower the rock with more radiation, and make it even deadlier when it arrives. The only real solution to an impact trajectory meteor is to adjust it's trajectory, and a nuke the absolute WRONG way to do that. A controlled small expenditure of energy, over a long period, is the best way to adjust a trajectory. A large, uncontrolled expenditure of energy is the worst way to do it.

Re:Oh great

[X0563511]

Yea, I knew that the pressure wave would be absent. But still, if anything (space craft) were in the local (within 100 miles I would say) area the radiation would cause issues. The sun (and other sources of radiation in space) are a loong way away, and we have a large atmosphere to absorb it.

The space craft I mentioned earlier in this post has neither distance or atmospheric shielding. But still, I have never heard of a reactor "Detonating" when it failed and melted down... at least recently. But ships and subs have the scram system. A spacecraft doesn't have a vast supply of cold salt water to drown the reactor in.

Re:Oh great

[SidV]

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.

Re:Oh great

[TheKidWho]

bet you don't even know what a meltdown is...

=) You: 0 Science: 1

Re:Oh great

[luna69]

i call thirds.

Re:Oh great

[taniwha]

I'm not worried about that - what worries me is if something carrying long-life nucleotides reenters and breaks up in the atmosphere - the result would be not unlike Chernobyl or an atmospheric test - I'm not much worried about gammas from orbit, I do worry about specs of Pu in my lungs.

So by all means launch them (from over the US, don't follow you previous nuclear plans and do it in the Southern Hemisphere for 'safety reasons', I live here - you take your own risks) - but once they're up use them outside earth orbit, I don't want them coming back down years from now

Re:Oh great

[iamlucky13]

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.

Re:Oh great

[Anonymous Coward]

I'm not worried about that - what worries me is if something carrying long-life nucleotides reenters and breaks up in the atmosphere

I have some VERY bad news for you; your body currently has litterally BILLIONS of nucleotides in it at this very moment. I suggest you seek a medical professional and ask that these nucleotides be removed as soon as possible, for both your safety and the safety of the human race.

Re:Oh great

[Anonymous Coward]

I was under the impression that a meltdown was an uncontrolled reaction (that incedently melts its way out of wherever it was reacting). A detonation would be something more... explosive. I don't think that can happen accidently, but meltdowns still are not pretty.

Re:Oh great

[WhiplashII]

The true badness of a nuke going off in space is that the Xrays (I think) ionize everything they hit - including metal sattellite skins, wiring traces, etc. The resulting surge of "static" electricity kills the entire electrical system.

I don't think humans would be bothered too much - we are pretty much transparent to Xrays - though they probably wouldn't survive too long afterwards with no electronics...

You can harden electronics against this of course.

Re:Oh great

[ShagratTheTitleless]

Make sure any treaties have an exception for the sun. Idiot.

Re:Oh great

[Anonymous Coward]

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).

Who will develop the reactor? The Naval Reactors (NR) program.

Will they release the design to public examination? No. NR spent several months arguing with NASA and even with some engineers within NR about classification. In the end much of the reactor design will be secret. Therefore the public will have an insufficient basis on which to question the safety of the system. Instead safety for launch and flight will be determined by a panel whose conclusion will be public, but whose basis for conclusion will be secret. This is no way to run a civilian space program.

Re:Oh great

[Anonymous Coward]

The current plan is for fission reactors to be used outside of an earth orbit.

All reactors used in space up to today have been used in low earth orbit. The USSR used about 40 such reactors to power spy satellites in low earth orbit. The US ran 1 such reactor in low earth orbit; this reactor is now in a 1000 year orbit of earth.

For those dreaming of a 10 or 20 year JIMO mission, it's worth noting that the US was able to run a reactor in space for just over 1 month before it broke. The record of the USSR is 1 year, but most of their reactors also ran on the order of a month.

Re:Oh great

[Anonymous Coward]

What exactly happens when a nuke is detonated in space?

If in earth orbit, large numbers of energetic charged particles are released, wrap around the earth's magnetic field, and fry satellites in reachable orbits. This has been studied as an anti-satellite weapon. It is very effective, but not very specific.

Re:Oh great

[Lockjaw]

Your original question, while not related to nuclear reactors (yep, they can't detonate), is a good one. The sun is very big, but very far away. A nuclear weapon up-close can exceed the sun's apparent output for a short time. The radiation from a weapon is different, too - there aren't any nuclear reactions at the sun's surface.

Check this out for more info on what a nuclear blast in near space can do: http://science.howstuffworks.com/e-bomb2.htm/. People don't die, but computers do.

Re:Oh great

[Ironsides]

We already have missiles that launch from space (thanks to clinton) which Bush has already used

Please provide link to source for missles in space. Could not find any information on space bassed missiles, much less any that were launched.

Re:Oh great

[X0563511]

But if the computers die, the people die shortly, right? So it is still a bad thing unless we shield the electronics.

Re:Oh great

[Retric]

30 miles still vary close when your talking about objects in space

I think the main advantage is there would be almost no fall out and you would be protected by the hull of your space ship / hull.

Anyway, 3d space so...

Looking at www.hiroshima-is.ac.jp/Hiroshima/radiation.htm
10 rads = No Apparent symptoms
100 rads = Changes appear in lymphocytes produced by bone marrow

2,500m from hiroshima would you got 12 rads now at 700 you are going to die but 12 is more a small long term risk. But at 30 miles you get (1 / (48 / 2.5)) ^2 of that dose which would be 1 / 368.64 of that or 0.03 rads which is fairly safe.

And yes I am skiping alpah and beta rays but:
A single piece of paper can stop an alpha ray effectively
Depending on its energy (i.e., speed), a beta ray can traverse different distances in water--less than 1 mm for tritium to nearly 1 cm for phosphorus-32.

Their might be some fallout stuck to your space ship with out gravity to pull it down and consitrate it on you your geting a lot less fallout than you would normaly. Your also not going to injest any radio active fallout which will help a lot. Now clearly there are larger bombs something 1000x that would fall into the 32 rads range which would increase your risk of canser over the long term but with a little shielding from the space ship your probably going to be fine.

PS: Once again this is in space at 30miles on the ground you get stuck eating / breathing fallout at that range which greatly increases your risks.

Re:Oh great

[Cyberherbalist]

That's probably why they're using NR for the source. You know, Naval Reactors, those reactors that sit in the US submarines and surface warships and operate nearly without break for years between refueling? If they were to put a Soviet-designed and built NR in there, I think I would not be so confident, though.

I saw this before

[Tracccer]

Thats right the Asgard, come and install their own warp engine

Re:I saw this before

[wfijvvz]

They don't want to end up being shackled.

Not to mention being tormented by an eagle as it tore at their immortal flesh and tried to devour their livers.

-
destroyed

Re:I saw this before

[mabhatter654]

actually, the Prometheus was Gou'ld based technology.. the asgard mearly enhanced it's materials to their maximum potential. Deadleus on the other hand is an Asgard based ship... and it's powered with a ZPM... so Gou'ld are offically a 'nusiance'...

I want to see replicators vs. wraith!!!

ahhh they stabilized it

[Anonymous Coward]

So they finally figured out how to stabilize naquandria...

Re:ahhh they stabilized it

[Fadeproof69]

Bah! I, for one, welcome our new Go'auld overlords.

Re:ahhh they stabilized it

[nightznoe]

bah, screw the Goa'uld, can I get Supreme Commander Thor's chariot? Ah the O'Neill...with 2 L's

Re:ahhh they stabilized it

[PakProtector]

What do you mean, 'new', human?

Re:ahhh they stabilized it

[quantum bit]

bah, screw the Goa'uld, can I get Supreme Commander Thor's chariot? Ah the O'Neill...with 2 L's

You want to get blown up?

Re:ahhh they stabilized it

[metlin]

Indeed, Master Anonymous Coward.

Re:ahhh they stabilized it

[rlp]

Bah! I, for one, welcome our new Go'auld overlords.

Oh, I get it - it's a reference to that TV show - "Wormhole Xtreme".

Re:ahhh they stabilized it

[Ride-My-Rocket]

Jaffa, kree tall!

Re:ahhh they stabilized it

[EvilTwinSkippy]

Quiet fool. You give away our presence prema...

Oh look at the ID number on that chucklehead. Gloat away.

JIMO

[Anonymous Coward]

Actually, funding for JIMO (Jupiter Icy Moons Orbiter) has been cut.

Re:JIMO

[nametaken]

Wait, then what's all the JIMO stuff on NASA's Prometheus site for? Did they just forget to take it all down? Or haven't gotten to it yet?

http://prometheus.jpl.nasa.gov/index.cfm?pageL1= mi ssions&pageL2=jimoSpacecraft

Re:JIMO

[applemasker]

Indeed, here is a quick link I was able to find.

Re:JIMO

[NOLAChief]

They're proposing to cut/reduce the funding for JIMO /Prometheus for the next FY. The entire budget's vaporware until Congress passes it, usually a couple months after it's supposed to be done in October.

That said, every NASA visitor's center I've been in still has X-33/Venture Star still prominently displayed. Go figure.

Re:JIMO

[Anonymous Coward]

I would not be surprised if it was cut. I think there is a 50-50 chance the mission will never occur, and is just being used as a loophole to develop nuclear reactors for Dept. of Defense purposes, under the guise of a scientific program.

Thank god

[QuantumG]

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.

Re:Thank god

[NanoGator]

"Finally, we can make some real space vehicles."

Yeah, but there's always the knee-jerk question about what would happen if a Columbia-esque accident occured with one of these. I'm not anti-nuclear, but I wouldn't blame somebody for pointing out that wreckage was found over a HUGE area.

Re:Thank god

[William Robinson]

Yes, This cerntainly is good news.

There are few reasons why fission (and fusion) based spacecrafts are supposed to be bad choices. 1. The mass of reactor is lot higher. 2. The nuclear(fission) reaction is not clean. The radiation (yes no shielding is enough) can be hazardous to equipments. 3. There are safety hazards for manned missions. 4. Failed launches will spread debris of nuclear waste all over the earth. 5. Operation/automation of nuclear reactor is much more complex task than operating the spacecraft itself. Fusion technology has a long way to go before it becomes operational in space. Maybe Cold Fusion first, yes.

Re:Thank god

[QuantumG]

Yeah, build it in space and launch the nuclear materials piece by piece.. a vehicle like this is never ment to enter the atmosphere.

Re:Thank god

[grozzie2]

You dont have to guess about the issues, just look at history. The soviets had a satellite de-orbit over northern canada many years ago. The search area for nuclear debris was rather large.

The politics of why they even bothered to look, and what was actually found, are another subject/debate unto themselves...

Re:Thank god

[NanoGator]

"Yeah, build it in space and launch the nuclear materials piece by piece.. a vehicle like this is never ment to enter the atmosphere."

I hear ya, man. Don't forget the ignorant masses, though. I personally don't fear a serious accident by this, but I know people that'd suddenly go shopping for fallout shelters.

Heck, a member of my family actually thinks a microwave can go bad and cause a mushroom cloud. Ugh.

Re:Thank god

[flyingsquid]

Yeah, but there's always the knee-jerk question about what would happen if a Columbia-esque accident occured with one of these.

Easy. We rename Project Prometheus to "Project Hubris".

Re:Thank god

[Short Circuit]

Heck, a member of my family actually thinks a microwave can go bad and cause a mushroom cloud. Ugh.

Throw a stack of CDRs in his microwave and watch him cower in fear. :)

Re:Thank god

[puzzled]

Coal is somewhere between one and thirteen parts per million Uranium. You can google and check the math but these numbers are not out of line:

We put twenty five *tons* of bomb grade Uranium 235 into the air each year with our current coal consumption. U235 is .72% of naturally occuring Uranium which means we're putting up about 3,500 tons of U238 as well. U238 which gets hit by neutrons from cosmic rays becomes ... Plutonium.

http://greenwood.cr.usgs.gov/energy/factshts/163 -9 7/FS-163-97.html

Don't tell any tree hugging antinuclear activists, but our most common form of electricity production will *always* produce more radiation than the most horrific nuclear fuel accident. Changes the picture a bit, doesn't it?

Its all cold war BS that we don't have nuke powered space vessels to take advantage of the 1,000X energy density improvement over chemical fuels. I hope this comes to an end soon ... I want fast Mars shots before I'm too senile to appreciate them.

Re:Thank god

[Thing 1]

I, too, am so glad that we aren't judged by the cows who share our genetic material.

(To think, I almost believed that idiot backwoods of Maine aunt (at least it was by marriage!) who burned (fucking burned!!! ) the Madonna tapes my sister gave her daughter, saying they were evil. It's so easy to blame your destructive behavior on evil, but in the end, well, you're just behaving destructively towards the people your God told you to protect and serve, so you're not really setting up a good future relationship, are you? </rant>)

Re:Thank god

[SidV]

Thank Jeff that 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.

In other words the background radiation of the debris area was less than the natural background radiation of natural Uranium rich areas like Western Africa, or in fact many parts of Canada, which have higher radiation levels than the debris area.

Re:Thank god

[khrtt]

There is simply nothing else that can power a long range mission. Bad as it is, fission power is really the only choice.

1. The mass of reactor is lot higher.

The energy density of that reactor is also a lot higher.

2. The nuclear(fission) reaction is not clean. The radiation (yes no shielding is enough) can be hazardous to equipment

You bet! It's about as bad as it gets. Radiation hardening of equipment is an old science, though, from the 60s. Modern integrated electronics are more delicate than the '60s transistor-based stuff, but still, radiation levels are not a show-stopper. Besides, no matter what you use for propulsion, you have to deal with cosmic rays anyways.

3. There are safety hazards for manned missions.

With a nuke you can go faster, reducing the exposure to cosmic rays, thus balancing out the radiation from the reactor.

4. Failed launches will spread debris of nuclear waste all over the earth.

What if you launch with a cold reactor, and only bring it online in orbit? Then the only radioactive material in the reactor at time of launch would be the fuel itself, i.e. only a few kilos of plutonium, inside a hardened shell that would survive reentry if the launch fails. This could be made safe enough - even safer than running a reactor on Earth.

5. Operation/automation of nuclear reactor is much more complex task than operating the spacecraft itself.

Just send Homer Simpson:-).

Seriously, Do you think the reactors on the submarines are manually controlled? Of course, on an unmanned mission there are no humans around to service it if it fails, but that's a problem with any space equipment.

Fusion technology has a long way to go before it becomes operational in space.

Fusion technology (short of bombs and stars) has a long way to go before it becomes operational. Period. This is one good reason to use a fission nuke. BTW, fusion, even cold fusion, would still create neutron radiation, so all the problems with the shielding remain.

Re:Thank god

[ramblin billy]

Uhhh...was it because they were by Madonna or as a protest of the lame outmoded audio cassette format? Inquiring minds want to know...

billy - damn, I just got used to 8 tracks

Re:Thank god

[Anonymous Coward]

As long as it doesn't turn to Project Debris...

Re:Thank god

[Anonymous Coward]

Uh oh, I suspect you're using facts and logic in your argument. Don't you know they've been strictly outlawed in public debate over the environment? Sheesh, next thing you know you'll be making an economic argument. And then Meryl Streep will have to personally attack you.

Re:Thank god

[Anonymous Coward]

By almost a dozen orders of magnitude.

Re:Thank god

[Guppy06]

"Yeah, but there's always the knee-jerk question about what would happen if a Columbia-esque accident occured with one of these."

Nuclear reactors are a lot more mass-efficient than chemical rockets, to the point where unpowered free-fall descents (like the one Columbia broke up in the middle of) may eventually become a thing of the past.

Also, the reactors are a lot more durable than a space shuttle orbiter.

Re:Thank god

[TheKidWho]

They say that the genetic difference between Aristotle and Einstein versus Average man is greater then the difference between Man and ape.

=)

Re:Thank god

[TheKidWho]

"BTW, fusion, even cold fusion, would still create neutron radiation, so all the problems with the shielding remain."

Depends on the fuel you use for Fusion =)

Re:Thank god

[hplasm]

Aha! To Mars and the outer planets in a coal powered spaceship!!!

Re:Thank god

[atom_pheer]

Coal is somewhere between one and thirteen parts per million Uranium.

Not to mention sulfur (that forms sulfur dioxide and causes acid rain), nitrogen, arsenic, mercury...

But really, I was under the impression that coal plants must filter out the heavy stuff, at least. How efficient we actually are at that? Anybody knows?

Re:Thank god

[puzzled]

We are pretty good, but go tour mainland China.

FYI the funny thing is ... there is a lot of natural radioactivity. Go read that report closely - coal fly ash = your average granite in terms of output. The big deal with coal burning is that you're putting breathable particles into the air ...

Re:Thank god

[nickstance]

Note: I am not an anti-nuke nut but the problem with your argument is this:

those 25 tons of uranium are spread over the whole globe, not just a small area. Chernobyl didn't realase that much radiation when it had its little boo-boo but that didn't stop a 30+ people from dying immediately, and another 200 or so being treated for radiation poisoning (not to mention varying degrees of contamination of the land, an increase in the thyroid cancer rate in the Ukraine, etc.)

You will never be able to convince people who live ANYWHERE near the launch site of this vehicle that "hey, it's ok we promise you won't die from this".

Re:Thank god

[QuantumPion]

"U238 which gets hit by neutrons from cosmic rays becomes ... Plutonium."

Not really, since free neutrons decay into a proton an electron with a half life of 5 minutes.

Re:Thank god

[Anonymous Coward]

Also, the reactors are a lot more durable than a space shuttle orbiter.

Why? You mean they could be more durable. But they don't have to be. And since the reactor will be desinged by a rather secrative group (the naval reactor labs at Bettis and Knolls Atomic Power) it's unclear how convincing they will be concerning the robustness of their design. (For which they have no previous experience, since this reactor will look nothing like a sub or aircraft carrier reactor.)

Re:Thank god

[DoraLives]

You will never be able to convince people who live ANYWHERE near the launch site of this vehicle that "hey, it's ok we promise you won't die from this".

Phoo.

I'm practically in the shadow of the launch pads here in Florida. Been here since the 50's. Lotta nuclear stuff has gone up over the years (despite the best ranting and raving the anti's could muster) and nobody seems to have panicked or moved away from the area. In reality, it's the fucking hurricanes that people need to watch out for. And they're not doing such a sterling job of that, either.

Re:Thank god

[mwood]

I hadn't noticed that they intend to leave the thing in Earth orbit very long either. You don't get to Callisto that way.

The whole thing is designed to go far, far away and not come back. Exactly what a lot of people would like to see happen to all radioactive material, near as I can tell.

Re:Thank god

[PhraudulentOne]

In other words the background radiation of the debris area was less than the natural background radiation of natural Uranium rich areas like Western Africa, or in fact many parts of Canada, which have higher radiation levels than the debris area.

That's why we have such killer Weeeed, maan!

heh

Re:Thank god

[mwood]

I'll accept your numbers for now, but we must also bear in mind that the U coming out of a smokestack is much more evenly distributed in space and time than the sudden eruption of relatively larger particles from a worst-case reactor breach. Spreading the stuff across a million km^2 over 30 years is a bit different from spewing 1/10 that amount over a thousand km^2 in an hour.

I agree that nuclear power isn't inevitably disastrous or even (when well run, which it sometimes isn't) inherently more harmful than any other way we have of releasing energy, but the raw numbers can be as misleading as raw fear. Carelessness with a nuke plant *can* cause a much worse mess than carelessness with a coal plant. Let's use nuclear energy, but let's also be careful in proportion to our ability to screw up really bigtime with that kind of power.

Re:Thank god

[Anonymous Coward]

It sounds like it was more because she thought they were a vehicle for Satan to enter into the poor innocents' minds

Re:Thank god

[Anonymous Coward]

Help me out here.. I can't decide what's funnier..

That "they" said it. (and who might they be?)
That you believed it.
That you repeated it.

And if you meant it tongue-in-cheek then.. err.. I meant this post that way too, so ignore it ;)

Re:Thank god

[EvilTwinSkippy]

Frankly we all die from something.

And pound for pound, a lot of the propellents used to get the nuclear stuff into orbit is FAR deadlier than the nuclear payload.

Re:Thank god

[Anonymous Coward]

Which is why the Cassini containment vehicle was designed to free-fall from orbit and impact on rock (or water, which reacts to impact similarly to rock at those speeds) without loss of containment. No, we have no experience with sending nuclear power into space.

Re:Thank god

[Ironsides]

but there's always the knee-jerk question about what would happen if a Columbia-esque accident occured

Columbia was re-entry. Challenger was take-off. I think you mean Challenger-esque. That aside, we have already built and sent into orbit reactors capable of surviving a launch pad explosion. In fact, one rocket did blow up and the reactor (or at least the radioactive material casing) survived intact, was recovered and was sent up on a later mission.

So, old technology and already been developed and tested.

Re:Thank god

[TheKidWho]

heh =)

Re:Thank god

[VoidCrow]

Search for 'accelerator driven systems'. It's a new type of fission reaction that requires an external fast neutron input to sustain it. This is where we should be looking, both for civil reactors, and for power sources for space drives.

Re:Thank god

[cthulhu11]

This is one reason why we should abandon the idea that coal is derived from swamp plants that died and decayed anerobically.

Re:Thank god

[tjstork]

Yeah but when you are talking about particles with a halflife of millions of years, who cares how much it is spread out.

Re:Thank god

[mwood]

SiO2 particles have a half-life of a hillion-jillion years, but they don't worry me. Time of exposure is only half the story, and besides, no living being is going to be exposed to radioactive material for millions of years.

One atom of U235 doesn't worry me. As the same amount of material is spread more and more thinly, there comes a point at which the dose for any individual is so small that he's very likely to die of age before it makes any significant difference. The damage is proportional, not just to length of exposure, but also to intensity of radiation, which is proportional to the amount of radiating stuff per unit volume. People didn't die instantly when they bought pottery glazed with uranium pigments; I honestly don't know whether anybody has shown significant health effects from long-term exposure to uranium-glazed dinnerware.

JPL

[tyleroar]

Project Prometheus has recently started a new web page (under JPL)

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

Re:JPL

[Anonymous Coward]

No because fortunately I'm not an idiot.

Re:JPL

[Anonymous Coward]

Yes.

Re:JPL

[Anonymous Coward]

>> No because fortunately I'm not an idiot.

unfortunately you are also a twit

Re:JPL

[eclectro]

Wow. Am I the only one that thought the JPL must be some license agreement like the GPL

Actually it is. It's the Jerk Public License.

Like for Nikon and their ilk.

Re:JPL

[Anonymous Coward]

Yes, you are the only one.

You haven't heard of NASA's JPL and you call yourself a NERD? Go back to la la land or wherever the heck it is you came from....

Before you ask ...

[Anonymous Coward]

"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.

It's a pleasant thought that the first software that aliens might encounter from Earth won't be from M$ ... I for one don't want to welcome our angry alien overlords after they get sick of the crashes :-)

Re:Before you ask ...

[dotslashdot]

Hopefully they won't mess up and forget to turn on some really important flag in the kernel, only to discover none of their software is compiled for USB.

Re:Before you ask ...

[grozzie2]

You obviously missed that chapter. The M$ software is proprietary, and will be kept here as the 'secret weapon'. When we do finally stumble on the borg (or they stumble on us), we'll seed the collective by planting Windows onto a drone. It'll only take a few days, and the entire collective will consist of millions of machines working at 2 tasks, first trying to fight off infections from other drones, and second, trying to infect other drones. The collective will grind to a halt, and humanity will prevail, until next week's episode....

Re:Before you ask ...

[GileadGreene]

Given that this mission is still in the conceptual design phase it's highly unlikely that they've spec'ed either a microcontroller or an OS at this point. Besides, JPL typically favors VxWorks as its RTOS (for example, both Pathfinder and MER use VxWorks). Do you happen to have a link to support your assertion about uCLinux?

Re:Before you ask ...

[B3ryllium]

... yeah, because then they'd never be able to dock their USB key from 50 million miles away ... no flash upgrades for you, jose!

On the other hand, if they made the USB key bootable and had the BIOS configured properly, they could (assuming the trajectory was precise enough ;-)) just plug it in and have something do a reset to boot from it ...

Re:Before you ask ...

[Anonymous Coward]

How the hell did this misinformation get rated "Informative"?

Re:Before you ask ...

[WindBourne]

When we do finally stumble on the borg (or they stumble on us), we'll seed the collective by planting Windows onto a drone.

Based on comments, and icons, on /. (and from what I have seen), I think that the Borgs have already landed and have successfully installed their OS on our planet.

Re:Before you ask ...

[GileadGreene]

Forgot to mention that, from what I can see on the uCLinux website, uCLinux hasn't been ported to any rad-hard or space-qualified processors. Which further reduces the odds that JPL would use it for a mission as important as JIMO/Prometheus.

Re:Before you ask ...

[Ender's in use2]

Imagine a Beowulf cluster of these things!

Re:Before you ask ...

[wfijvvz]

Mod this guy down. Or mod him funny. It's funny. But it's a sad funny that I can't bring myself to laugh at.

Re:Before you ask ...

[Excelsior]

we'll seed the collective by planting Windows onto a drone....The collective will grind to a halt, and humanity will prevail.

Your scenario highlights that Windows Activation actually will doom humanity when the borg are unable to install Windows on multiple systems.

Re:Before you ask ...

[ramblin billy]

Speaking of crashes...

Are we uping the anty concerning the possible negative ramifications of shouting out into the void? Right now we're basically yelling -

"Hey it's us! We're called h u m a n s. Look isn't our planet great? Look at all the resources! Look at all the people! See how advanced we are - we can send uncontrolled unmanned probes who knows where. We're peaceful too! With this technology we don't have much choice. Well, here's where we live - just follow the TV signals. See ya soon!"

So the new plan is to send a toxic little present with the message. I hope we don't lose the whole planet in a liability judgement.

billy - yes I'm paranoid...now go away before you set off the booby traps

Re:Before you ask ...

[Anonymous Coward]

Yes, in the 24th century there is no money, thus no corporate edition.

Re:Before you ask ...

[rjw57]

PARENT IS KNOWN TROLL.

Even the most cursorary investigation will reveal this to be false.

Re:Before you ask ...

[Anonymous Coward]

Darn tootin' ....
You wouldn't believe how many times I've seen that bastard 'Anonymous Coward' trolling this site!

Re:Before you ask ...

[cybergrue]

The onboard microcontrollers on the craft will run the uCLinux kernel, with Gentoo userspace.

OK, so are they going to get Arthur C. Clark to come in and type "emerge world" if the probe needs an update while it is orbiting Europa?

Re:Before you ask ...

[Anonymous Coward]

Gentoo, huh?

I'll work on the nuclear reactor/ion drive. It's probably twice as easy as installing Gentoo. (BTW, how long will it take to emerge from Europa? I gotta quit complaining about DUN!)

Solar Panel

[dotslashdot]

Looks like runs on Solar power as well, based on the project pictures. Is that for running the experiments or also for running the guidance computers?

Nuclear worries

[MagPulse]

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?

Re:Nuclear worries

[__aaclcg7560]

That's right. If Iran and North Korea decide to build a nuclear-based space program, then that would be a problem for the U.S. since Radical Islamists and Crazy Commies can now terrorize space instead of their neighbors. China is a different story as long as U.S. companies get contracts to build subcomponents at a hefty profit.

Re:Nuclear worries

[psychgeek]

No one really worries that much about Nuclear technology in space. If it were NUCULAR on the other hand...... then there would be cause for concern!

Is this science fiction?

[John Seminal]

Because there ain't no way the Bush White House is paying for this.

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?

Re:Is this science fiction?

[Surt]

Unfortunately, what we really want is for the converse to be true. Sadly, the converse is far less likely.

Re:Is this science fiction?

[TummyX]

What do you mean? It's nuu-ku-laa powered!!

Re:Is this science fiction?

[Deanalator]

there ain't no way the Bush White House is paying for this

Think of who you are talking about. Can you think of anyone with a 5 year old mentality who wouldnt get excited about getting a nukeuler spaceship?

Especially when he can be the first kid on his block with one. I dont know who comes up with these names, but a nuclear space initiative called Prometheus (the greek god who brought fire to earth) just seems a bit creepy.

Re:Is this science fiction?

[Anonymous Coward]

Wow. That was absolutely the worst photoshopped picture I've seen in a year. Fark has NOTHING on NASA.

Re:Is this science fiction?

[Ender's in use2]

Actually it was the Bush Jr. Whitehouse that started pushing for nuclear powered spaceflight again.

And just how often do you get to use Larry Flint as a source of reference material to back up your /. post?

Re:Is this science fiction?

[FleaPlus]

Because there ain't no way the Bush White House is paying for this.

Actually, the Bush administration explicitly gave the go-ahead and requested funding for Project Prometheus. I dislike most of what Bush does, but this was one of the few things he did that I supported.

Of course, this made anti-nuclear folks like Bruce Gagnon quite spastic.

Re:Is this science fiction?

[Prune]

Instead of going to Jupiter, how about getting to Mars with a little more reliability, with people?

Unfortunately, the technology they are developing has very low thrust and takes forever to accelerate. Nuclear electric propulsion first converts nuclear energy to electricity, and uses that to drive efficient ion engines. This allows very long acceleration and eventually huge speeds, but the low thrust is inefficient for people. As for nuclear thermal propulsion, which allows enormous thrust, these have been tested back in the early 60s, but will not be used anytime soon due to anti-nuclear public opinion.

Re:Is this science fiction?

[CaptainAvatar]

It's not just anti-nuclear people who don't like this. Robert Zubrin was pretty damning about the way the nuclear electric lobby hijacked JIMO and caused the cost to balloon due to unrealistic program goals, leading Bush eventually to not request any more money for it. It's a cool idea and I'd love to see it tried out, but the nuclear industry's greed has postponed it, at best.

Re:Is this science fiction?

[Anonymous Coward]

I really don't get this. I mean, if we're going to be launching reactors in space, why wouldn't nuclear thermal propulsion be an option?

Re:Is this science fiction?

[johnjay]

Two things to make your fears come true.

W.'s term in office has, so far, been more space-friendly than either of his two predecessors.

These are the BIG GOVERNMENT Republicans in charge. They haven't met a government program they didn't like. Why should NASA be any different?

At least the second one allows you to keep saying bad things about Bush...

Re:Is this science fiction?

[FleaPlus]

Thanks for the link.

To clarify my position, I'm actually very much in favor of Project Prometheus, but I'm not so sure that JIMO is the best initial application for this. I'd prefer to see a prototype nuclear reactor on a much smaller and less complex test mission first, before sticking it on something massively complicated like JIMO.

Space.com had an article on possible alternatives a little while back. A snippet:

NASA is reviewing a list of fission-powered missions that could pre-empt the Jupiter Icy Moons Orbiter (JIMO) effort now being eyed for space travel no sooner than 2015.

A special study team has identified six potential candidate missions that could be done sooner, have shorter mission durations, and would be far less difficult to implement... The six ideas are:

* Technology Demonstration Mission to test fission power system in deep space with no specific science goal or destination.

* Lunar Geophysical Orbiter that in extended mission mode could serve as a telecom asset for future lunar missions.

* Next Generation Mars Telecommunications Station.

* Near Earth Object (NEO) Asteroid Mission that would involve stopovers at multiple objects, perhaps landing hardware on a NEO to assess the ability to modify the trajectory of a celestial body.

* Venus Orbiter, more like a Magellan II spacecraft that would carry out low altitude runs over the cloudy planet with state-of-the-art radar.

* Astrophysics Mission that would use high power levels from a fission power source, likely sending collected science information at very high data rates.

Re:Is this science fiction?

[syousef]

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?

You think manned space flight to Mars is more reasonable and less bloated? It ain't a 3 day trip like it was to the moon.

Re:Is this science fiction?

[Craig_P92669]

You should be ashamed of yourself for insulting 5 year olds in such a manner.

Re:Is this science fiction?

[NardofDoom]

An industry lobby hijacking a government program to make its masters money?!? That's unpossible!

Re:Is this science fiction?

[Anonymous Coward]

Geez, you can put the ppls in suspended animation with hydrogen sulfide gas already. It's not like biology is rocket science or anything.
http://www.freep.com/news/nw/less22e_20050422.htm

Re:Is this science fiction?

[RichardX]

Re: your sig..
How can you be skeptical of alternative medicine when there are such wonderful and scientifically proven products out there as GulliGo, the homeopathic remedy for gullibility? ;)

Russian nukes have been in space for decades

[Anonymous Coward]

Just google rorsat

That liquid is oil!

[Anonymous Coward]

Start grunting!

The U.S. has a good track record.

[crottsma]

The reason it's not an issue for the U.S. to use nuclear power is because we're genuinely interested in only using nuclear power in virtue of its energy-providing capabilities, not in virtue of its WMD capabilities. If Iran had a consistent record of pacifist-endeavors, it, too could be part of this wonderful cause. The minute that NASA workers strap nukes to their chests and run amok in downtime Washington D.C. is the minute I revoke my support for the U.S.

"Nu-cul-ar, it's pronounced, nu-cul-ar."

-Homer Simpson

Re:The U.S. has a good track record.

[John Seminal]

The reason it's not an issue for the U.S. to use nuclear power is because we're genuinely interested in only using nuclear power in virtue of its energy-providing capabilities, not in virtue of its WMD capabilities. If Iran had a consistent record of pacifist-endeavors, it, too could be part of this wonderful cause. The minute that NASA workers strap nukes to their chests and run amok in downtime Washington D.C. is the minute I revoke my support for the U.S.

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.

Re:The U.S. has a good track record.

[grozzie2]

The reason it's not an issue for the U.S. to use nuclear power is because we're genuinely interested in only using nuclear power in virtue of its energy-providing capabilities, not in virtue of its WMD capabilities.

I'll believe that when the US stops manufacturing nuclear weapons. Until then, it's just a bunch of hypocritical pots hollering at the kettle....

Re:The U.S. has a good track record.

[ThreeE]

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.

Re:The U.S. has a good track record.

[Anonymous Coward]

I thought it was common knowledge that the United States has not manufactured nuclear weapons in over 15 years. See http://nuclearweaponarchive.org/Usa/Weapons/Wpngal l.html

And what that has to do with space based nuclear power systems is beyond me. I don't see the point you're trying to make here, care to elaborate?

Re:The U.S. has a good track record.

[Anonymous Coward]

But then the USA decided to help Hussien, we sold him all the arms he needed to attack Iran for over a decade

Idiot. Hussein's weapons came from the former Soviet Union, Communist China, and France. While there were a small number of weapon sales from other countries (just about every weapons producer on the planet, in fact, with the notable exception of the USA), not a single weapon in Iraq's arsenal was from the U.S. The only thing that even comes close were a few helicopters (Bell 212s, for example), and those were unarmed VIP transports sold as civilian aircraft, not military.

This can be easily verified by looking at a copy of Janes from the appropriate time, available at just about any decent library.

The United States DID sell weapons to Iran, however (even the remarkable F-14, although that was done during the period of rule by the Shah). Iran (not Iraq, Iran) was sold the TOW ATGM, the HAWK SAM system, and various other defensive weapon systems during the Reagan administration (although technically such sales were through Israel, strangely enough).

No doubt you can find a number of "sources" that support your lie that the "US armed Iraq", but that simply shows that you lack the intellectual integrity to distinguish even the most elementary self-evident truths. Sure, the media repeated that lie a great number of times. But that's no excuse, because you could see for yourself in those same media reports that Iraq was using T-72s and Type 69 tanks, not M1A1s or M60s, used BMPs and BTRs, not Bradleys, and was firing AK-74s (or 47s with some reserve troops), not M-16s. Their aircraft were various Migs and the occasional Mirage (F-1, M3, M2000), not F-16s. In every category where even the slightest information was available, it was obvious where Iraq was getting its equipment. But with all the vast evidence, you and your band of tiny-brained little twits insisted on believing something so ridiculous that it was demonstrably false just by spending a few seconds in thought.

So the only real question is, are you an idiot, or just a damned liar that believes everyone else is an idiot?

Re:The U.S. has a good track record.

[Anonymous Coward]

Selling weapons to Iraq had absolutly nothing to do with the Shah being deposed and kohmeni coming to power.

Anyway, at the same time we were BUYING weapons from Iran to sell to the Contras in Nicaragua...

Re:The U.S. has a good track record.

[Guppy06]

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?

Re:The U.S. has a good track record.

[Anonymous Coward]

How?

Re:The U.S. has a good track record.

[meringuoid]

But I do know that your world is better because of those US nuclear weapons built by us hypocritical pots.

Hai. Arigatou gozaimasu, Aisanhawaa-sama.

Re:The U.S. has a good track record.

[Guppy06]

"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."

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.

Re:The U.S. has a good track record.

[Thomas Miconi]

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

Re:The U.S. has a good track record.

[coopex]

Go read Secrets of the Samurai by Oscar Ratti and Adele Westbrook, and realize that Japan would have lost more than half of its population in an insane struggle for "honor" had it not been for the A bomb.

And this concludes today's lesson on why revisionist historians are complete morons.

Re:The U.S. has a good track record.

[John Seminal]

And here, ladies and gentleman, is a shining example of the output of the US public school system!

My knowledge did not come from the US School systems, it came from someone who lived in Iran during the Shah rule. His gradnfather was a judge, and his father worked in the government. Once the revolution started they ran to France. From there they came to the USA. He said that he had some family which was not able to leave Iran in time, and was executed.

According to him, the USA did support the fall of the Shah. To hear him say it, the difference between living in Iran during the Shah and after is like night and day. Iranians had freedoms under the Shah, they could watch western TV, they could buy just about anything. After the Shah fell, women had to dress up, no more western TV, no more freedom. Reading the wrong books could get you arrested.

As for Hussien, he was a nobody. They USA helped his bathist party gain power. Once in power, the USA realized it was in our interest for Iraq and Iran to stay in a constant fight. So we supplied Iraq with weapons.

You might be able to tell me what is in the books, I can tell you what people who lived there told me. I'll take their first hand account as real.

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 this is a reason for war? Country A is more friendly with the USSR than the USA, so we'll aid countries to make war with Country A?

What was the USA worried about? What would have happened if Iraq and Iran never went to war? They would not have spent their oil money on wepons and huge armies. I seem to remember from history class that both countries at one time had a good university system. Could we have had a super power in the middle east if they were no so buy spending money on war?

Re:The U.S. has a good track record.

[John Seminal]

I posted many comments here instead of duplicating them:

http://hardware.slashdot.org/comments.pl?sid=14734 1&threshold=1&commentsort=0&tid=160&mode=thread&pi d=12345978#12348850

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.

This is not wholly true. I know some Iranians, and while they love the US people, they might strongly disagree with the US government. They know firsthand how the USA makes foriegn policy, and how the USA is willing to have "collateral damage" if it is in the interest of the USA.

I think the Iranians hate the USA government as much as their own.

Re:The U.S. has a good track record.

[ThreeE]

See any basic high school history text. Winning the cold war, ending WWII in the Pacific, etc.

How quickly you forget.

Why, snails could move faster ...

[2TecTom]

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?

Re:Why, snails could move faster ...

[Daniel Dvorkin]

Don't blame NASA. I guarantee you there are a shitload of NASA scientists and engineers who are chomping at the bit to build this thing, and have been for decades. It's the politicians who make the spending decisions you should blame, and more generally, the voters who elect those politicians; if it weren't for our general loss of national will as regards space exploration after we beat the USSR to the Moon, we'd have a fleet of nuclear-powered spacecraft moving both cargo and people all over the Solar System by now.

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.

Because the vast majority of businessmen, "geniuses" or not (mostly not) are incapable of thinking past next quarter's results. The potential ROI on space travel is huge, but it's also very long-term. Interesting that you mention "new continent" as an example -- it's worth remembering that the early voyages of the Age of Exploration were done on government funding. I think the lesson here is pretty obvious.

Re:Why, snails could move faster ...

[QuantumG]

Space development is the same old problem. As soon as you know enough technical information to make informed decisions about space travel you have lost the ability to think like a business man. If you could get a 500% return on a 10 year investment with minimal risk I guarentee that you would see private efforts to acheive that. As we don't, it is clear that no-one has come up with a business plan that can deliver that kind of return as of yet. Even a similar return over a 25 year period would be acceptable to some investors.. 50 years is somewhat more pie-in-the-sky and looks even more risky.

Re:Why, snails could move faster ...

[rebelcool]

"Because the vast majority of businessmen, "geniuses" or not (mostly not) are incapable of thinking past next quarter's results."

Actually you can blame this too on the general public. The funds needed to undertake such projects are such that you need public investment. It's the investors who don't look past the next quarter's return.

There are plenty of businessmen willing to gamble on it. But nobody will give them enough money to try.

Re:Why, snails could move faster ...

[Anonymous Coward]

Maybe the lesson is that if we set up colonies on other planets, they'll declare freedom and start bombing other countries on Earth.

Re:Why, snails could move faster ...

[B3ryllium]

Colonization was done by companies. I know this because PBS told me via the medium of Reality Television, aka Colonial House. :)

Re:Why, snails could move faster ...

[2TecTom]

Oh, trust me, I agree, the politicians are far, far worse, however, I doubt the engineers and scientists really get to call the shots at NASA or anywhere else for that matter. Pity, eh?

However, I also don't dismiss the resposibility of the "People" either. In my opinion, we, as a society, have simply sold out.

Oh, and as to the government funding of the early American explorations. It is true the first few were, in part, funded by the respective crowns, however, that changed very quickly and the next century was filled by eutreprenurial ventures of exploration and trade, military conquest, imperialism, and quests for personal fame and glory.

In fact, we've never moved so slow, or been this affuent. Perhaps there's a connection?

Re:Why, snails could move faster ...

[2TecTom]

so sry, it's spelled "responsibility" of course. Darn finglers, anyways. |~)

Re:Why, snails could move faster ...

[ion_nation]

Part of the problem for some of this technology is that the development time is very long. The Prometheus ion thruster will probably have to run for over 20,000 hours. To get a good idea of the erosion on the thruster (the life limiter), they need to run in a vacuum tank for quite some time- probably at least 8,000 hours in this case. Of course, simulations can predict life to some extent (that's actually what I do), but NASA doesn't rely on it. The NEXT ion engine is what I've been working on for the last three-four years, since it's inception. They've done a 2,000 hour wear test and are getting ready for a longer one. All this before it ever gets put on a spacecraft, because you don't want the thing failing halfway through a mission. Even though NEXIS and HiPEP (the two possible Prometheus ion engines) are under development right now, I don't expect they'll be ready before 2010.

Re:Why, snails could move faster ...

[Anonymous Coward]

It's not a matter of just long term.. it's that space is potentially not even profitable at all.
Although every slashdot poster probably thinks that cheap launch systems aren't around merely because of 'NASA myopia', the facts point towards the ignorance of the critics.
Launch, even to orbit... is very difficult and very expensive. Scaled Composites (Rutan et al, spaceship one) only had to hit 100k ft. or so, and were not required to achieve orbital velocity. It's not that accelerating is impossibly difficult in space, it's that carrying all the g'damn fuel up that high isn't energetically profitable.

I don't see anything but a -100% ROI until some major breakthrough in launch propulsion comes along.

Re:Why, snails could move faster ...

[Short Circuit]

I dug up some corroborating evidence for you. It doesn't explain Spanish conquistadores, though.

Re:Why, snails could move faster ...

[TheKidWho]

Your an idiot, there doesn't need to be a major advancement in launch propulsion. You wanna take a guess as to how much the fuel for a Delta IV heavy costs? Less then a million dollars. The problem is an engineering and logistics problem not propulsion.

Also SPACE IS NOT PROFITABLE??? Yeah sure... Trillion Dollar asteriods are certainly not profitable right right right???

Re:Why, snails could move faster ...

[QuantumG]

Asteroids.. I bought that line too, it was good and it made me feel warm inside. But getting those asteroids back to a market is expensive. It's not cheap launch capacity we need, it's cheap de-orbit capacity. Then we could send an automated probe to mine these asteroids, make rocket fuel from the resources on them, fire payloads back to earth, perform magical de-orbit technique, collect materials from where they land, perform any processing necessary, and sell em. All that would take so much logistics that a simple launch will look easy in comparison.

Re:Why, snails could move faster ...

[Anonymous Coward]

Your an idiot...

Actually, it's "You're an idiot". Who's looking dumb now?

Re:Why, snails could move faster ...

[Anonymous Coward]

Scaled Composites (Rutan et al, spaceship one) only had to hit 100k ft. or so

No, they hit 100km.

Re:Why, snails could move faster ...

[WhiplashII]

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?

I am currently working on this - so perhaps I can give you some insights. The main problems are conflicting visions for the future, and people having problems basing business plans in the present.

For example - it makes no sense to start an aerospace company right now. There are more aerospace companies than there are payloads to orbit (literally - there are 50 orbital flights a year, and hundreds of little space startups). Even if you have "special sauce" that makes you 10x better than your competition, making others believe your rocket is reliable enough to launch their billion dollar payload will take a lot of planning, flights, and sales dollars. Not to mention that you are competing in a government controlled industry, where the winners have already been chosen to a large extent. Progress is being made, but it is slow.

Additionally, the comercial launch people (who are the most likely to be on your side) also have a conflict of interest - they have already launched billion dollar satellites. What happens when you suddenly launch their competition at 1/10 the price? Suddenly they lose a couple billion of their balance sheet. (To be honest, this won't stop them - but it effects them psychologically at least!)

The last major problem is that everything you can think of in rocket design has been thought up and patented or made public. Even though the patents have expired, it means that a startup company that makes a cheap rocket has no IP protection - so the second to market gets to use their IP without having to fund the development, so they would wipe the floor with them. Making information on your super rocket design public is a sure way to kill it. And just to make sure you know, rocket design is still hard! The rocket has to be 80-95% fuel. The engine has to operate at temperatures far higher than the melting point of any possible material - even diamond or tungsten. The engine has to be nearly 100% efficient (except exhaust losses), because it can't weigh much but has several GigaWatts flowing through it!

All of these problems must be addressed in your business plan - and remember, your business plan needs to be convincing enough that your wife would be willing to invest. That's why I am taking it slowly, spending two years finalizing my business plan - making sure that I have covered all the angles. I need to talk to all the stakeholders, and make sure that they will not fight against the project. Hopefully, in one year the public will hear about it. (Of course, the fact that I get my EMBA at that point is also convinient.)

I am optomistic though - the plan has a 10x return in the first 2 years (high risk), 2x return in the next year (medium risk), and a somewhat normal return for the remaining years (almost no risk).

Of course, I could also have answered your question with this line:

What are you waiting for? If you think it will work, why don't you do it? Startups are what make our economy work!

Re:Why, snails could move faster ...

[WhiplashII]

You say that it is engineering and logistics, but the problem is deeper. As you point out, the direct costs of fuel are miniscule (about $10-$20 per pound), but all that fuel has to be carried in a tank. And the tank cannot weigh more than 1-5% of the fuel weight. And the engine cannot weigh more than 1-2% of the fuel weight. Etc, etc, etc.

Then you have to think about what happens when this rocket crashes or goes off course. You are carrying so much fuel and oxidizer that you will make a spectacular explosion - so you have to get all sorts of government clearances to launch. On top of that, you need insurance - if your payload costs $1B, and you can only prove a 90% safety record, your insurance will be at least $100M.

Of course all this added together only reaches about $1500 per pound, while current launches cost $5000 per pound. The single largest contributer to launch cost is vehicle R&D. Because it is so hard to make a rocket work, rockets are extremely expensive to design. I am sure you have heard how most rockets cost billions of dollars in R&D - well, spread that over 100 launches. You say "Hey, thats only $10M per launch! What gives?

The time value of money raises it's ugly head. If you launch twice a year, then you must earn the amount of money a similar investment (say in the stock market) would have made - otherwise your investors don't give you their money, they invest it in stocks (duh!). So assume really low risk (which isn't really true unless you are doing government launches), so you need a 10% return. Say we spent $2B in R&D. 10% is $200M - over 2 flights, $100M per flight!

The only way around this is a higher flight rate - but there is no market for that. (Remember, your business plan has to deal with the current reality, not a perfect world where everyone comes and uses your rocket!)

And yes, I think I have solved these problems...

Re:Why, snails could move faster ...

[Anonymous Coward]

if it weren't for our general loss of national will as regards space exploration after we beat the USSR to the Moon, we'd have a fleet of nuclear-powered spacecraft moving both cargo and people all over the Solar System by now.

That's ridiculous. The moon could be made of nothing but uncut cocaine and it still wouldn't pay for the costs of a space program. There's a reason the loss of national will for the space program - it was propoganda half of ICBM research spending, and that's it. There is no good reason to put man on the moon other than to plant an American flag.

Countries aren't stupid. If there was a large financial incentive towards moving cargo around space, countries would be tripping over themselves to do it.

And comparing the exploration of space to the exploration of foreign continents is simple-minded.

Re:Why, snails could move faster ...

[TheKidWho]

My point still stands =) The majority of the cost is in the logistics and engineering of the thing.

Personally I can't wait until SpaceX can get the FalconV launched, with the promised $/lb ratios they have, that thing is going to be a hit if it is very reliable.

The DC-X was also an awesome project that NASA shouldn't have cancelled, althought it wouldn't have been capable of heavy lift it could certainly have worked very well and cheaply for the launch of humans, not to mention it could work as a lunar/mars lander(send the cargo in super heavy lift vehicles). Because of this im also really interested in what Blue Origin(Owner of Amazon's company) is going to be doing. A bunch of their engineers were from the DC-X project and considering that the Owner of Blue Origin is reach as heck, they might be able to do something very very interesting.

Just curious, any more info on this company you are starting up?

Re:Why, snails could move faster ...

[FleaPlus]

The single largest contributer to launch cost is vehicle R&D.

Are you certain about that? I was under the impression that the largest cost contributor, at least for manned systems, it's the cost of paying the "standing army" required for maintaining and prepping the craft while it's on the ground. I recall hearing a figure of around 20,000 people needed to maintain the shuttle.

Re:Why, snails could move faster ...

[Eminence]

• Hopefully, in one year the public will hear about it.

Ugh... then... when do I apply for a job there? *cough*

Re:Why, snails could move faster ...

[TheKidWho]

Yeah, I understand those problems. They are biggies and IMO anything short of a super shuttle or a space elevator isn't going to make the goods from an asteriod cheap to bring back. But still, there are industries that can develop in space with nearly unlimited resources. Personally I think that's something definetly worth pursuing. Also, we probablly COULD develop a super shuttle with 500kg deorbit capability, or send all the raw goods into LEO, and send up a big capsule with a cheap rocket to LEO to pick up the goods and bring them back down. Although both of those things might end up making the goods cost way too much. How about just keeping things in space and let people start living in space, develop new industries there.

As far as logistics go, they could be, in my opinion automated enough so that it would only take a minimal amount of ground crew to actually transport the goods.

Plus its not like in the 1600's when they were growing tobacco in the colonies they had cheap access back to england. But they did it and profited off of it!

Oo and the reminds me, one concept that NASA had was to use Mass drivers on the lunar surface to send lunar manufactured goods down to the earth. With strong enough heat resistant casings, you could easily send large amounts of cheap raw materials onto the earth.

AND Since the moon has 1/6 the earth's gravity and a negligible atmosphere, you could in theory actually bring down asteriods into a lunar crater and mine it there and then ship it straight off to a lunar mass driver.

Re:Why, snails could move faster ...

[TheKidWho]

That's for the space shuttle, he's reffering to commercial launch vehicles like the Pegasus or Atlas/Delta Rockets.

And yes for the shuttle the reason its so expensive is because the thing basically has to be rebuilt every time its flown, and it takes a LOT of people to do that.

Re:Why, snails could move faster ...

[QuantumG]

Putting people in space does not help people make a return on their investment. That said, I'll now contradict myself. Suppose you built a nice big space station on which 1 million people could live. Each of these 1 million people would have to pay a heck of a lot of money to keep themselves supplied with goods. Water will be the top priority. When people are living in orbit and paying $100/ltr for water they're gunna jump at the chance to pay $50/ltr for water mined from an asteroid. Of course, this is not a sustainable colony we're talking about, that's just a business model for really rich tourists to go to space.

As for the moon, there's no real need to "bring down" asteroids into a lunar crater.. craters were formed by asteroids in the first place. Every major crater probably has more asteroid material in it than any of the near earth asteroids we are tracking today. So mining the moon probably is more economical than mining near earth asteroids as moving to a new crater once you've mined out an existing crater is a very cheap operation.

Re:Why, snails could move faster ...

[coopex]

Hmmm..., I'll agree about coke, but if the moon was made of carfentanil, 4000x potency of heroin, with heroin at about 100k/kg, bring back only 100kg, and you get 40 billion in revenue.

Re:Why, snails could move faster ...

[Anonymous Coward]

maybe all space programs are pointless because the govts know the aliens are out there and have their element115 technology and can fly everywhere for free, but wont release that info until sometime in the future, so until then no point wasting lotsof effort, except token research and blackops funding.

Makes total sense tho, only reveal the tech once its either total war, or total economy collapse, its not the first time govts kept high tech secret for eons, re telescope first invented 100 years before the official date.

Re:Why, snails could move faster ...

[2TecTom]

I understand your point, and yes, you are correct. These aren't easily or quickly accomplished.

My point here is that the time involved in engineering is far exceeded by the time wasted economically and politically dithering. However, my main point is that these extremely entrenched plutocracies are incapable of producing effective results. They seem to exist largely for the benefit of those whom we entrust to guide them.

Re:Why, snails could move faster ...

[2TecTom]

While I greatly appreciate the information and even admire your goals, my point was aimed at the speed of space development on the part of NASA. Indeed, I'm a big fan of the current home brew space race, and I believe it's the result of how others have also become frustrated. Sadly, as a technical writer, I find it somewhat difficult to construct a working spaceship in my garage. Really, I think I'm putting my faith in all the hardware hackers out there. Engineers, you just gotta love em.

Re:Why, snails could move faster ...

[WhiplashII]

My point still stands =) The majority of the cost is in the logistics and engineering of the thing.

Ah, I see - sorry, I thought you were talking about unit creation engineering, not R&D.

Just curious, any more info on this company you are starting up?

Unfortunately no, other than that it will be cool! ;-)

I have to get all the proof of concept and legal work done before I can talk about it. Maybe it will be the first site I submit to /.

Re:Why, snails could move faster ...

[WhiplashII]

You have to understand that NASA is not in the business of providing space access - they provide science and research. If NASA had a rocket that could fly to the moon and back for $0.20, you would not be allowed to go in it. Only astronauts (and senators, apparently) would be allowed (though if it really was that cheap, friends would sneak on board and be overlooked).

The problem is that NASA, as a government entity, would not be allowed to take you even if they wanted to. Private industry would have to step in.

BTW, the problem is not an engineering one - those are solved, and have been for some time. The problem is a business problem - and a technical writer would almost certainly be useful there!

Re:Why, snails could move faster ...

[2TecTom]

So ... where's the research and the science? Yes, I know about Hubble and all the rest, however, my point is we should have so much more by now. I think private industry did step up, only I fear that only the big boys were really invited to play, and look how they mucked that up, eh!

We need to get back to grassroots, open, shared and practical development. The government needs to stop being an overpaid nanny. These people at the top need to be convinced they'd be even better off, if we were better off. I can't think of a better way to get the economy off than a wholesale expansion. Seriously, I believe that only by moving past our boundries, can we hope to overcome our current seemingly overwhelming limitations. The future is up there. Shouldn't we be trying a little harder to get there?

Oh, and on that note, I've noticed a sad lack of appreciation for technical matters on thew part of the so-called business people. The last time I looked, I'm sure the founding fathers meant for the economy to serve us, not the other way around.

Re:Why, snails could move faster ...

[WhiplashII]

Oh, and on that note, I've noticed a sad lack of appreciation for technical matters on thew part of the so-called business people. The last time I looked, I'm sure the founding fathers meant for the economy to serve us, not the other way around.

Interesting comment. Would it be fair to say that there is also a "sad lack of appreciation for business matters on the part of the so-called technical people." It is one of the most interesting things that I learned from my marriage is that different people have different viewpoints, and that both viewpoints are valid. By trying to see the other viewpoint, we can learn about ourselves.

As for the economy serving us or them, the economy is a machine - it serves anyone that knows how to use it. In the US, that machine doesn't even require a password (nobility, born into the right family, etc.). Those that believe that the economy should be serving them do not understand how that machine works - and therefore only minimally profit from its existence.

For example, what is money? Money is not a source of power, money is not a tool, money is not the root of evil - money is a device used by society to measure the relative value of objects, plans, and effort. This can be abused, of course, but that is the basic idea. If someone else is making more money than you, what that person is doing is (at least locally) more valuable to society. Don't try to tear that person down, try to get yourself to that position - do what they do. The way the economy works it that I make your life easier and we share the difference in ease. (The same statement as you make my life easier and we share the difference in ease.)

I could go on for hours, but you really didn't want to hear any of this, ne? Sorry!

Re:Why, snails could move faster ...

[2TecTom]

In my humble opinion, the problem it what you say seems to be in the "we share the difference in ease".

Actually, the way it is, the profits earned are hardly shared, if at all. In fact and as far as I can see, the great majority of those doing the work, sure don't seem to receiving an equitable or fair share of the profits. Or, for that matter, calling any of the shots!

Which brings us nicely back to NASA. ;~)

Re:Why, snails could move faster ...

[WhiplashII]

That's why I said ease, not profits, because the word profits seems to confuse people. Since you asked, I'm going to keep spouting my ideas - you may feel free to ignore me if you want.

Management (especially building a new company) is a lot harder to get right than most people think - and it is far more valuable to society than any other endevour I can think of. Thats why the rewards for successfull management are so large. But to get back to the split of "ease":

The worker gets a certain percentage of the profits directly - they are paid. In addition, since society as a whole is better off (and they are a member of society), they receive an additional compensation. The manager almost always gets a larger payment. Since, as I stated earlier, money is the way society evaluates value added - it is apparent that the manager has done something worth a lot more. You probably don't believe me here, but ask yourself these questions:

If the worker decided to leave, what is the cost it would take to replace them?

If the manager decided to leave, what is the cost to replace him/her?

You would have to agree that there is a difference in price. Ask yourself why that difference exists. What is the value created from an additional laborer in the workforce? What is the value created from an additional company in the economy? The ratio of good managers to management required is lower than the ratio of good workers to workers required - so there is a (large) incentive to get people to stop being workers and start being managers.

Society is using money to tell you what it needs - but all you see is that someone else is getting the money. Become what society needs! We need more entrepenours! Do it!

If you do it (to help society, not to get cash), you will get rich in all senses of the word. But you will also learn that it is amazingly hard work, high risk, and worht every penny society pays for it.

Then you can be like me and try to pull up those that follow...

Re:Why, snails could move faster ...

[2TecTom]

Sadly, I'm afraid I must completely disagree with you here. The difference in price you work so hard to justify is exactly that; too hard to justify. The ratio of CEO compensation to lowest paid employeee is some 475 to 1 in the USA but only 15 to 1 in some European countries. In actual fact, the reason management is so overpaid is simply due to self interest on the part of senior management. In fact, recently several very large and long established enterprises have been bankrupted by the greed of these same managers whom you seem to feel somehow deserve all the profits while taking few, if any, personal risks.

If employees truly enjoyed a fair profit sharing pay system, more people would have more money. How anyone can expect capitalism to function, when so few have access to any real capital, quite frankly, is completely beyond me.

I hope this completely states my position, as I'm not sure it's possible to be more clear.

Re:Why, snails could move faster ...

[WhiplashII]

I agree that their are problems, but I disagree that they are as widespread as you seem to beleive. To put it simply - those companies go out of business, and the CEO no longer makes that much money. To me, that is the market working propperly. If money were taken away from managers and "given" to employees, fewer people would become managers. (You agree there, right?) Without managers, there are fewer positions for workers. So by "fairly" spreading profits and not paying managers the market value, you change the economy so that instead of having almost everyone employed for what the market will bear, you have less people employed for higher wages.

The most useful person in our present society is someone that can derive excess value from the work of others - managers. Good managers are exceptionally rare - so rare that most managers are doing jobs that they are not qualified for. I beleive that is the real problem.

We need more managers, we need more people that can create value from jobs. Otherwise, we can only play a zero sum game...

Re:Why, snails could move faster ...

[2TecTom]

Actually, no, sorry but I can't agree that fewer would become managers nor that the money would be "given" away. Rather, the employees are not being paid the fair amount that they have earned. This demoralize a company and poor products and service is the end result. We aren't as competitive as we could or used to be. We've become overweight and top heavy. In fact, while any other single country would be hard pressed to accomplish what the USA has done, several economic blocs all already poised to. Globilization is leveling the playing field. We need to become leaner instead of meaner.

See?

Re:Why, snails could move faster ...

[Anonymous Coward]

How is comparing the exploration of space to the exploration of foreign continents being simple-minded? I'll bet you can't justify that assertion!

Re:Why, snails could move faster ...

[WhiplashII]

All I can really say is that I disagree. I think that what you say is true of large companies in general, but it has always been true of them. I think the economy is built by small companies, and large companies exploit the returns. I think top heavy large companies get replaced by smaller companies, employees get only their replacement value - just like the managers.

I have used this knowlege to position myself to take advantage of the larger companies weakness - and to put me in a position to replace their functionality. I have gone from the lowest income bracket to one of the highest - with no monetary assistance from anyone. I am disabled, but the government did not bail me out - and that made me stronger. I am not bragging, but I really do think the world would be a better place if more of us stepped up and started small companies. And those that do will reap the benefits.

Giving people money always ends up hurting them. Look at past examples: welfare families, lottery winners, etc. It puts you in the wrong mindset. (Mind you, I understand what you are saying - when I was bedridden and the givernment refused to help me I was pretty mad!)

It is interesting that you mention globalization. I grew up living in various countries, and as you say "globalization is leveling the playing field." What I have noticed, though, is that the other countries are starting to become competitive with the US (to the enormous benefit of their populace), not that the US is getting weaker. It is not a zero sum game - and the more people we pull to the top with us the better off we all are!

I guess as I have dealt with businesses, and seen how corporations work at the highest levels, it has made me realize that the people at the top are just people, for the most part just trying to do the best that they can. Of course all you see in the press are the bad apples - but there are over a million companies in the US, so there will always be something bad to talk about. You just have to realize that the view the media gives you is very one sided. (Whenever the media reports something, think this: How could that man (or woman) be a good man that is being taken advantage of by the media?)

The only other thing I want to say is this: business deals are built on trust. There is always a way to wiggle out of a contract. There is always a way to stiff your partner. The reason the economy works is because people are good for the most part, and so you can trust them. Something that worked extremely well for me was to find someone outside my area of expertise (he was a businessman, I was an engineer) and befriend him. He saw things differently than I did - and my friendship allowed me to understand where he stood, which got me to where I am today. (Wonderful apartment on the 54th floor of a high-rise with my daughter crawling all over me!)

Do what is best for you! I wish you all the luck in the world!

Re:Why, snails could move faster ...

[2TecTom]

Sure, you made it without assistance. However, it's an assumption of yours that everyone has the same strength of character that you seem to enjoy. Sure, you had disadvantages, but I'd bet you also had advantages such as a supportive and caring upbringing. The problem is you now expect everyone to have the same advantages and strengths that you were able to draw upon. I'm terribly sorry to have to inform you of this, but sadly, it simply isn't true. Many people simply don't have the inner strength to overcome the difficulties they face. As a society, it behooves us to help others to help themselves. The small things that could be done to help those who need it the most would be paid back in spades once these people became self sufficent. In truth, most people don't receive the help they truly require due simply to the greed of the people above them.

It is how we treat others that most reveals how much we truly can care about ourselves.

Re:Why, snails could move faster ...

[WhiplashII]

Well, we just seem to have different points of view on human nature. I can understand your point of view and I am glad people like you exist, because we all have times when we need help - and your existence makes the world a better place. I agree that helping others become self sufficient repays society a hundredfold, we just seem to disagree on what the best method of providing help is. You seem to lean towards the caring and giving love camp, while I lean towards the tough love camp. But I also strongly believe that having both types of love is essential!

One point I would like to add - humans are amazingly maleable. The same people that under Hitler or Tojo became the most infamous human rights abusers are now the most pacifistic under different conditions. So people that do not currently have any necessary qualities (such as strength of character) can aquire them. That's a lot of my objective. I strongly recommend change of environment - for better or for worse, you will learn something.

I respect your viewpoint, I think people with your viewpoint are essential - but not sufficient.

Ehhh..

[Guppy06]

"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?

Re:Ehhh..

[Anonymous Coward]

One (maybe the only surviving) NERVA rocket is on display in the back yard of the US Space and Rocket Center in Huntsville, AL. Huntsville is the home of NASA's Marshall Spaceflight Center.

Re:Ehhh..

[Anonymous Coward]

NERVA was the 1960s. What you are looking for is TIMBERWIND.
http://www.thebulletin.org/article.php?art_ofn=ja0 3rogers_014
Google "TIMBERWIND nuclear" and I'm sure you'll be uber-happy.

Isn't that quaint

[chaffed]

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.

Re:Isn't that quaint

[Anonymous Brave Guy]

Way O/T, but what the heck...

That model was always the odd one out. Most of the human ships and technologies in B5 are remarkably credible for a SF series; rumour has it the guys designing the Star Fury model talked to some guys from NASA about how they'd design such a ship for real, for example. But who in their right mind would design a carrier ship where the main egress for the small craft was right at the front, where all the incoming fire is going?

They'll be putting the bridge of a starship right on top, next to the hull with pretty lights saying "Shoot here!", next... <sigh>

Re:Isn't that quaint

[Anonymous Coward]

But who in their right mind would design a carrier ship where the main egress for the small craft was right at the front, where all the incoming fire is going?

I guess it's so they fighters have an inital velocity in the general direction of the enemy, or perhaps the ship designers for the show didn't think about that. However, since they went through the trouble to actually calculate and model the effect of the spin on B5's Star Fury bays during launch, I think we can cut them a little slack.

Re:Isn't that quaint

[Anonymous Brave Guy]

I guess it's so they fighters have an inital velocity in the general direction of the enemy, or perhaps the ship designers for the show didn't think about that.

I'm guessing the latter; as you say, if they're thinking deeply enough to launch the fighters from B5 using the rotation, I'm sure they'd also have considered that your fighters probably wouldn't want to be heading directly for your enemy in combat. Maybe they should go watch a few episodes of Andromeda to learn about how tactics in spacefights work? ;-)

EVACUATE! EVACUATE!

[solafide]

A malfunction has caused the spacecraft to dump its highly radioactive fuel onto [insert densely populated area]. Evacuate this area immediately! If you do not, possible side effects are nausea, vomiting, and death!

LOL!

Heat Sinks / Spreaders?

[reality-bytes]

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.

Re:Heat Sinks / Spreaders?

[GileadGreene]

You are 100% correct. The large panels are radiators to dissipate excess heat. Large radiators are a standard feature in designs for space-going reactors, since the conversion from thermal energy to electrical energy is far less than 100% efficient.

Re:Heat Sinks / Spreaders?

[qbwiz]

Consider, also, that the first project will be the Jupiter Icy Moons Orbiter. Ther's a reason that those moons are icy, and that reason is lack of sunlight.

Re:Heat Sinks / Spreaders?

[Anonymous Coward]

So the nuclear-heated turbines are for electrical generation, and will be far more efficient than the traditional thermonuclear batteries (ala SNAP)?

Re:Heat Sinks / Spreaders?

[GileadGreene]

Different mode of operation. Most of the SNAP series are Radioisotope Thermoelectric Generators (RTGs). They produce thermal energy through radioactive decay of Plutonium (not fission!), and directly convert it to electrical energy using thermoelectric devices (the Peltier effect). I don't recall what the efficiency of thermoelectric conversion is off the top of my head, but I don't think it's that good - the main draw for using it the the lack of moving parts.

The move to fission is driven by a desire to get more power (even a large RTG will only produce a few hundred Watts, versus the kilowatts they expect to get from a reactor). I don't know exactly what the trade-offs are with using Brayton cycle vs thermoelectric (or thermionic) conversion. The Russians have flown a number of thermionic nuclear reactors (the Topaz series), and they seemed to work fairly well. I suppose it's possible that Brayton cycle reactors are more efficient than thermoelectric/thermionic conversion. But even if you assume a (highly unlikely) 90% conversion efficiency, a 100kW reactor would leave you with 10kW of thermal energy to dump. At this point it's probably worth noting that even the most high-power satellites we currently fly (the Boeing 702 comm-sat) operate on a mere 15kW of power. So you're talking about being able to radiate as much energy as most satellites generate in total. And as I said, that's based on some pretty optimistic assumptions about the efficiency of the Brayton cycle.

Re:Heat Sinks / Spreaders?

[Ender's in use2]

"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"

You're right that taking photovoltaics would be pointless, but this has more to do with the low Watts/m^2 of the solar light as far out as Jupiter. Past about Mars orbit you need nuclear power, whether it's a reactor like in this case, or simply the heat given off by radioisotope decay like with Cassinni.

Re:Heat Sinks / Spreaders?

[Anonymous Coward]

so making popcorn isn't going to be an issue?

Re:Heat Sinks / Spreaders?

[iamlucky13]

In fact, you have to get rid of nearly all of the energy. Most of the energy that is converted to electricity is then used to operate something which then converts it back to heat (like a computer chip). The two energy expenditures I can think of that don't yield waste heat are the propulsion system (ideally), and the radios (again, ideally).

I read somewhere that the Brayton cycle generators they plan to use will have a thermal efficiency of approximately 25%. That means that a 10kW electrical system will need to deal with 40kW of heat. Of course, I expect it would be possible to use a significant portion of that to heat the propulsion fuel.

Re:Heat Sinks / Spreaders?

[GileadGreene]

In fact, you have to get rid of nearly all of the energy. Most of the energy that is converted to electricity is then used to operate something which then converts it back to heat (like a computer chip).

A good point. In fact, thermal design for spacecraft (at least at the preliminary stages) is typically carried out under the assumption that all of the electrical energy not leaving the spacecraft as RF radiation is converted into thermal energy.

The two energy expenditures I can think of that don't yield waste heat are the propulsion system (ideally), and the radios (again, ideally).

Unfortunately, both of those items are less than ideal. It's not uncommon for a spacecraft transponder to be on the order of 20% efficient (or worse). Likewise, the ion propulsion systems they are planning on using for Prometheus have an electrical->thermal conversion efficiency of around 70-80%. Which for a 20kW thruster (e.g. the proposed NEXIS thruster) means 4kW+ of waste heat.

Of course, I expect it would be possible to use a significant portion of that to heat the propulsion fuel.

The current proposals for Prometheus involve nuclear-electric propulsion rather than nuclear-thermal propulsion. I don't believe that heating the propellant in a NEP system helps (although I'm not really a propulsion expert, so I'm quite prepared to be corrected on this).

Re:Heat Sinks / Spreaders?

[Suidae]

[RTGs] produce thermal energy through radioactive decay of Plutonium (not fission!), and directly convert it to electrical energy using thermoelectric devices (the Peltier effect). I don't recall what the efficiency of thermoelectric conversion is off the top of my head, but I don't think it's that good

Efficiency of production RTG's is about 3% to 7%. Nobody has produced one that hits 10%.

Re:Heat Sinks / Spreaders?

[GileadGreene]

Thanks.

Woah..... 7000 Seconds

[illectro]

That's 10 times the best chemical engines ever designed.

Re:Woah..... 7000 Seconds

[NarrMaster]

Mmmm... Ion drive goodness.

Re:Woah..... 7000 Seconds

[Fadeproof69]

Can't we just launch the ion engine in a steel ball, paint it black, and add black rectangular wings to the sides? I call it a (using the doctor evil finger quotes) "TIE fighter"

Re:Woah..... 7000 Seconds

[Anonymous Coward]

It's better than that. The 700s chemical fuels are fairly exotic (tri-propellants and the like). Your standard H2-O2 mix tops out at 528s and the Shuttle's engines for various reasons only run at 460s. (numbers from The Starflight Handbook)

Re:Woah..... 7000 Seconds

[anderskc]

well, a specific impulse of 7000 seconds is a bit deceiving. True, conventional fuel/oxidizer rocket engines have, at best, a specific impulse of around 450 seconds. But thrust = Isp*dm/dt*g0. For the ion engine, the mass flow, dm/dt, is very small. Despite a specific impulse much greater than conventional rocket engines, the thrust provided by the ion engine is miniscule. Moreover, because Prometheus is so massive, the corresponding acceleration is tiny.

The point is you cannot run a conventional rocket for months at a time. Also, the specific impulse of the nuclear powered ion engine is much larger than that of previously used ion engines (Deep Space One's ion engine had an Isp of about 1200 seconds I think).

Re:Woah..... 7000 Seconds

[WhiplashII]

Heh, I seem to remember a chemical Isp in the 850s - something amazingly nasty like flourine - ozone - lithium - Hydrogen.

Of course, you could do one better with radioactive ozone (it's lighter) - that way when your rocket explodes you could spread radioactive goodness all over the launch area!

Light is, of course, radiation. [n/t]

[Alexei]

Light is, of course, radiation.

Re:Light is, of course, radiation. [n/t]

[Manhigh]

Hey, thats text!

Re:Light is, of course, radiation. [n/t]

[Anonymous Coward]

Err... electromagnetic radiation (photons) isn't the same thing as particle radiation (alpha particles, beta particles, neutrons, etc).

Re:Light is, of course, radiation. [n/t]

[Anonymous Coward]

You're right. Light radiation (e.g. gamma, X-rays) is dangerous at far longer distances.

At least three Russian RORSATs have fallen

[Anonymous Coward]

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.

Re:Oh great - It's a question of size really...

[TechnoGrl]

>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!

Not really... the sun puts out something like 1400 kiowatts/meter^2 before it gets to the surface... and that's mostly *not* in the form of gamma rays .

A small 100kw nuclear reactor core puts out a lot more radiation in a smaller form factor (like a cubic meter or so) ...and most of *that* is in a far more energictic and harmful form that *does* produce gamma rays and other nasties...

Prometheus, you say?

[Anonymous Coward]

Great. Let's just hope that the ships don't encounter the Minbari along the way ...

Re:Prometheus, you say?

[Anonymous Brave Guy]

Nah. Goa'uld, sure. Asgard, maybe. But I'm pretty sure Minbari is a different series.

Re:Prometheus, you say?

[shutdown -p now]

As long as Minbari don't have oil, they should be safe.

Re:Prometheus, you say?

[Anonymous Coward]

(Grandparent poster).

Babylon 5. One of the pivotal events that happened before the start of the series was the Earth-Minbari war. The war started when a Human vessel encountered a Minbari vessel. The Minbari did something that was intended as a peaceful gesture; the humans misinterpreted, panicked, and attacked.

The name of the Human vessel was the Prometheus.

Re:Prometheus, you say?

[Anonymous Brave Guy]

Well, I'll be... There is someone in the world who's even more of a B5 nut than me! Sorry, I got the Minbari half of the reference but missed the Prometheus bit entirely. Time to go watch In The Beginning again. ;-)

Re:Prometheus, you say?

[drhamad]

You make me sad ;) But yeah, SG1, B5, both Prometheus. Can I start a "bring back B5" campaign now? ;)

Hmm.. Prometheus?

[Anonymous Coward]

Was I the only one that immediately thought of the ridicious ship that was on ST Voyager? You know, the one that splits up into three pieces?

Ah, nevermind.

JIMO a no-go?

[elh102]

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."

Looks like those "early mission plans" have been revised. See the second half of this article. Here's the relevant paragraph:

JIMO, whose launch had already been pushed back from around 2012 to 2015, faced what NASA called "concerns over costs and technical complexity," leading the agency to effectively cancel the mission. JIMO was intended to be the cornerstone of Project Prometheus, a nuclear power and propulsion program; NASA will instead seek a less-complex alternative mission to demonstrate those technologies.

Nuclear power is not relevant to this discussion

[dbIII]

The reason it's not an issue for the U.S. to use nuclear power is because we're genuinely interested in only using nuclear power

Nuclear power as applied today is an expensive way to boil water and the peaceful side of the bomb. This spacecraft is something completely different and has little to do with those 1950's white elephants, and should be taken on it's own merits.

Some radioactive things are very good ideas.

The thing to do with Uranium

[Veteran]

The best hope of man kind long term is to burn up as much uranium and plutonium as possible - if there are no nuclear fuels, there won't be any nuclear war.This project not only burns up fuel, it gets it off of the planet - where we don't have to deal with the waste.

Before it is activated the nuclear fuels are not very radioactive so a crash on takeoff doesn't do much.

Re:The thing to do with Uranium

[MarkLR]

Its possible to extract uranium from seawater. It's not economical compared to mining but if that's all you have to make nuclear weapons from you can afford to do it.

Re:The thing to do with Uranium

[Anonymous Coward]

I think you are thinking of deuterium, not uranium.

Re:The thing to do with Uranium

[crypto55]

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. :)

Re:The thing to do with Uranium

[ckaminski]

Care to post that paper?

Re:The thing to do with Uranium

[SidV]

Deuterium is part of some water molecules.

Uranium is dissolved in seawater in solution.

Re:The thing to do with Uranium

[MoralHazard]

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!

Re:The thing to do with Uranium

[coopex]

Uranium is about $80/kg http://www.romawa.nl/nereus/uranium.html, while gold is $436/oz = $15347/kg.http://goldinfo.net/gold1.html

Took less than a minute with google.

Re:The thing to do with Uranium

[ckaminski]

Which has fuck-all to do with whether Uranium is the 8th most plentiful metal on earth?

Re:The thing to do with Uranium

[spauldo]

According to this link uranium occurs about 4ppm in the earth's crust.

This site seems to agree, although I'm not overly sure how the whole "log" thing works with abundance - it's parts per million, but put into a log scale. Perhaps a geologist would like to comment on that.

Neither one suggests that uranium is the 8th most abundant material in the earth's crust As far as the mantle and core go, who cares? It's not like we'll be able to get to them any time soon.

These Links both suggest that uranium is certainly not the 8th most abundant element in the crust. although they disagree on if it's potassium or magnesium. Uranium isn't anywhere near those scales, since 4ppm is 0.0004%.

Comments from someone with geology training would be helpful here.

Re:The thing to do with Uranium

[coopex]

Let's review some basic economics. When there is a greater supply of some good, ceteris paribus, the price is lower. Uranium has a large supply, being the 8th most common metal, so its price is correspondingly much lower than gold. Learn to use your brain dumbass.

Re:The thing to do with Uranium

[draco ni]

According to: this page, Uranium is the 92nd most common element in Earth's crust. Due to its density, it's probably more common in Earth as a whole, but for the forseeable future, unless it's in the crust, we won't be getting our hands on it.

Re:The thing to do with Uranium

[ckaminski]

Sorry that came off antagonistic... I typed faster than I thought.

But still, where in those two links does it mention Uranium being the 8th most common metal? Other than being more plentiful than gold and silver.

The only table *I* came across that purports to list this data http://gpc.edu/~pgore/Earth&Space/minerals-notes.h tml
via google (most common elements in earth's crust) (no parens in search) doesn't list uranium at all.

In fact, based on the process of nuclear fusion, I call bunk. Elements lighter than Iron will be much more plentiful than the higher elements simply because everything degrades to Iron.

So I say: Prove your claim with a link. Price of a material has absolutely nothing to do with its abundance in nature. Witness diamonds. Nuff said.

Re:The thing to do with Uranium

[coopex]

I apologize for the rude remark.

So, after far too much time searching, I finally came across this site: http://www.physicsdaily.com/physics/Abundance_of_t he_chemical_elements#Abundance_of_elements_in_Eart h.27s_crust.

From the chart it appears that Uranium is about the 50th most commen element. So crypto is full of shit and should be modded into oblivion, and ckaminski should be modded informative. This should be obvious, as ckaminski points out by how heavier elements are created.

Re:The thing to do with Uranium

[ckaminski]

Thanks for the link. I'd sure like to know what you did differently, because I never found it. :-D

Re:The thing to do with Uranium

[cmsavage]

Uhh, check that table again. 92 is its atomic number, not its abundance. Only the first 20 entries in that table are ranked by abundance.

Re:The thing to do with Uranium

[coopex]

In the order I see them in my history:

eighth most common metal
"eighth most common metal"
"first second... tenth most common metal"
10 most common metals
10 most common metals uranium
most common elements
most common elements tungsten tin (since www.uic.gov said that uranium was about as common as them, about 2 ppm)
uranium most common metal
common metals
uranium most common metals
most common metals in the curst
abundance of tin
abundance of uranium
eight most common metals
most common metals
most common metals uranium
most common metals uranium tungsten tin
most common metals uranium tungsten tin earth's crust

Finally, abundance of elements.

So it was over an hour of work, and finding out that aluminum is the most common metal in the crust, how the various rankings change based on in the universe, solar system, earth, and earth's crust, and that thinking for a second (re: production of elements by fusion and supernova) would save much time.
In the interest of providing this info for future reference, I followed the webelements on wiki, and present you this:

For the first time, on the internet, a list of the most common elements, with their abundance in ppm by weight.
http://slashdot.org/~coopex/journal/

This typing is just extraneous, to circumvent the gayass lameness filter. I shall now just be typing conversations I hear in the computer lab, to make the average of characters per line greater than it is currently at 11.5. You know alot more about it than we do. It'll be like a white stripe. See what I'm thinking, Check this out. Then I flatten it out, I flatten the hose out. But the problem is, getting those, getting that texture to lay on the ground. Mitchell is somewhat busy right now. What am I doing? My question is does that sound like a good idea? But apparently... people want. You know just avaoid the whole hose. Now it is at 15.2 characters, So I shall entertain you with a reading. Ahem, The Walrus and the Carpenter. The sun was shining on the sea, shining with all his might, doing his very best to make the billows smooth and bright, and this was odd because it was the middle of the night. The moon was shining sulkily because she thought the sun, had got no business to be there after the day was dune, it's very rude of him she said, to come and spoil the fun. The spelling nazis must remake about my correct use, I verily did use it's and not its did I use, and furthermore grammar did I spell not with e or u. The walrus and the carpenter were walking close at hand, they wept like anything to see such quantities of sand. If this were only swept away, they said it would be grand. If seven maids with seven mops, swept it for half a year, do you suppose the walrus said, that they could get it clear, I doubt it said the carpenter, and shed a bitter tear. etc etc, they trick a bunch of oysters to come with them, the mother oyster warns them they the walrus and the carpenter are up to no good, and the walrus and the carpenter eat all the baby oysters. Dammit, its still only 20.5 characters per line. WTF is with this lameness filter, considering our "beloved" leader has said the most lame comment ever, "No wireless. Less space than a Nomad. Lame." Yep, the firehouse should not need a clip anymore. I'm just trying to figure out why you can't. Yeah I see what you mean it looks like it's just teleporting. Oh I know why. Why? Go to... Oh scott, can I submit to this version in here. Ok, I'm gonna download... Just download torque SVM, yeah, I'd check it out to the local machine. And now some unauthorized retyping of the dailyillini.
Garbage plan won't charge UI students.
By Eric Chima, Staff writer
A new Champaign law would charge landowners for leaving trash on their property during move-out week, but area landloards say students living in the city have no need to fear suprise fines being passed on to them. The Law, which unanimously passed a Council poll April 12, and will come up for a f

Re:The thing to do with Uranium

[ckaminski]

Excellent! With your permission I'd like to post this @ ckaminski.com (I collect all sorts of esoteric knowledge). You can email me with proper attribution if you'd like.

Lovely work. :-D

Re:The thing to do with Uranium

[coopex]

Go right ahead, just put "Organized by Joe Cooper from webelements.com"

Actually...

[BobPaul]

Project Prometheus has recently started a new web page

Actually, I was trying to figure out how a yet-to-be-built space craft has designed a web page. But, I suppose it isn't rocket-surgery.

Risk

[spagetti_code]

Can we talk about risk here...

Its one thing to have a nuclear reactor down the road with a million to one chance against blowing up...

Its another to be lobbing one up into space where, during launch, there is a 100 to one chance of it blowing up.

Risk = chance of happening x consequences

Here the consequences are catastrophic. Can anyone enlighten me on how this is a good thing?

Re:Risk

[Anonymous Coward]

Plutonium can be incased in high temperature ceramics that can survive reentry. This would prevent the spread of plutonium should the rocket fail to reach orbit.

This type of technology could be used to divert Asteroids in the path of Earth. The rewards out weigh the risks.

Re:Risk

[cybercuzco]

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.

Re:Risk

[Anonymous Coward]

Are these minutes from a NASA funding hearing?

Re:Risk

[Rorschach1]

No, he wasn't worried about the nuclear submarines because he didn't know about them.

Now you've done it.

Re:Risk

[spagetti_code]

It wont be a point source of radiation, should be there an explosion (especially a high altitude one) - it will be a widely dispersed contamination of radioactive material.

And I am actually worried about nuclear submarines - not because of their current state, but when they degrade and release their material.

Re:Risk

[the_2nd_coming]

hmm.. some uranium dust spread over a few thousand square miles... as compared to the radioactive crap spewed out by coal power plants every day? dude. you are nuts to be worried about 2 pounds of uranium that MIGHT blow up and spread out a bit.

Re:Risk

[uberdave]

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.

Re:Risk

[spagetti_code]

Ok - I am feeling somewhat mollified by the comments. Thanks.

Re:Risk

[WhiplashII]

You are talking about simple risk handling. USA launch permits require that the probability of death be less than 30 deaths per million launches.

This is not hard stuff - their are similar requirements for terrestrial reactors.

Re:Risk

[naveenkumar.s]

An interesting question about nuclear wastes. The vehicles may not come back to Mother, with the A-energy they can be at space for long periods. What can they do with the wastes. Just let it float away in space?
It may be a 6' X 6' box, but it still gives an eerie feeling to leave it there. They can someday reach our orbit, or even our atmoshpere
May be I am just paranoid?

Re:Risk

[Fizzl]

May be I am just paranoid?

Yes, definitely.

Re:Risk

[Anonymous Coward]

Yeah, see, that's the thing, I mean.

...and perhaps have a lifespan of about 20 years.

Then what? It just uneventfully stops working... we hope. Sure it may go chernobyl, and sure it is orbiting a gigantic ball of hydrogen/unexploded star, but hey, why not? Carpe diem!

When your car throws a rod, that's bad. When a nuke throws a rod, that's really bad!

Re:Risk

[wiredlogic]

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).

Re:Risk

[spagetti_code]

hmmmmm... 30 deaths per million launches.

If you are talking about the shuttle, then we are currently running at 14 deaths from about 100 shuttle launches (rounding for simplicity), or over 100,000 per million shuttle launches. The shuttles are running a bit behind.

If you are talking about satellites, then I don't know what the numbers are, but they blow up all the time. The fact that they achieve 30 deaths per million launches is because they are unmanned and usually launched over the sea, not because of any inherant safety record.

Re:Risk

[WhiplashII]

Sorry. That is, of course, 30 uninvolved persons deaths. It doesn't count if you kill yourself - that is perfectly fine...

frost 4ist

[Anonymous Coward]

hand...don't you nee3 to succeed

Mod parent up!

[Anonymous Coward]

Mod parent up!

Project Orion was cooler, though

[armed ahmed]

Of all the atomic propulsion systems, project Orion is the one that struck me as 'reasonable', despite the atmospheric miniature nukes. The sheer payloads that it would enable make Orion the number one option for human spacefarization.

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...

...anyone interested in nuclear propulsion and the most avant-garde of rocketry, read about "Project Orion" if you already haven't.

http://isbndb.com/d/book/project_orion.html

Re:Project Orion was cooler, though

[argent]

Yeh, Orion was the hottest thing this side of project Pluto.

Re:Project Orion was cooler, though

[Eminence]

• 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...

Then why do you keep on living? Remove yourself - one cell of a brain-tumor - immediately from the universe.

Re:Project Orion was cooler, though

[FleaPlus]

Having a universe with a human population spreading effectively in it summons an eerie image on a spherically expanding brain-tumor to my mind...

I find it curious that you'd think of it as a brain tumor, instead of just a rapidly expanding brain. Personally, I can think of few goals more noble than expanding intelligence and conscious thought throughout the universe.

Re:Project Orion was cooler, though

[FleaPlus]

Oops, that was supposed to be posted to the GP, not the P.

Re:Project Orion was cooler, though

[spauldo]

Ob. Comment:

We have to find it first!

Sorry, had to say it.

Re:Project Orion was cooler, though

[armed ahmed]

Being a part of a malignant growth that recognizes its future outlook, I feel that it is more productive to try and do whatever I can to change the course of human developement into a more sustainable kind.

As I said, humans have not yet started to spread effectively in the Universe, so I don't really know whether removing myself or any other part of humankind from the universe would be a good or a bad thing at this stage. That said, even though I haven't removed myself from the universe, I think I have removed myself from the tumor by making the decision of never parenting a child :)

I would hope that if humans ever reach the level of consensus needed for projects like Orion, they would also find a way of leading a sustainable existence so we could avoid the whole "tumorness".

Re:The thing to do with Uranium is...

[Anonymous Coward]

Uranium/Plutonium standard.

The Gold Standard used to be the basis for our money. We should go to Uranium and Plutonium as the basis for money. The life of a general that wants to start a nuclear war and bankrupt his country in ten minutes will probably be much shorter than that. It will be a strong disincentive for nuclear war.

This is not un-typical for Gummint projects

[leonbrooks]

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. (-:

Re:This is not un-typical for Gummint projects

[ckaminski]

How does one get this mysterious DVD?

Re:This is not un-typical for Gummint projects

[Anonymous Coward]

It's TUPOLEV.

Re:This is not un-typical for Gummint projects

[mwood]

"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."

That's actually rather good provisioning. A P-90 as a motor controller is probably 99% idle even when it's moving things, and you'd want redundant gear anyway because, hey, even brand-new equipment fails and scope time is hideously valuable.

Re:This is not un-typical for Gummint projects

[mwood]

That's okay; he also misspelled "Kazakhstan", so it balances out. :-)

Re:This is not un-typical for Gummint projects

[wiredlogic]

Agreed. Anything more powerful than an 8086 is overkill in such a simple application. For the sake of maintaining a simple 32-bit code base I'll grant the possbility of using a 386 but a Pentium is unnecessary.

Re:This is not un-typical for Gummint projects

[Rei]

Are Tupolevs really that bad? Lets see... in 1999 (first year that I found numbers for), Russian airlines carried 20 million passengers, and had 43 deaths. Assuming an average distance travelled of 1,000 miles, that's about 0.215 fatalities per hundred million miles. While that's 10 times more dangerous than current US airlines, it's only one sixth as dangerous as it was to fly in the US in 1960, and is still 8 times safer than driving an equivalent distance. Talk about much ado over nothing - they're not flying deathtraps or anything :P

Yes, Russia is poor, and can't afford all of the maintainance and training that they need. But barring a *relevant* risk to your astronauts, why insult your host country over it?

Re:This is not un-typical for Gummint projects

[Humorously_Inept]

Has either of you ever opened up one of those handheld computers that come with Meade and Celestron telescopes? I'd be interested to know what sort of CPU's inside. Probably a Z80 or some other 8-bit microcontroller like a PIC.

A warning

[Anonymous Coward]

All these worlds are yours except Europa.
Attempt no landings there.

Massive waste of money

[mclaincausey]

I think we have more pressing issues than bankrolling pointless exercises. I'm curious about the solar system, but am more concerned with dealing with the immediate crises facing us here on the Third Stone.

Re:Massive waste of money

[Zebra_X]

I think you are wrong. We (humans) are always going to have issues; almost every human on earth has problems. Our issues are not getting any less complex or solvable as time progresses.

Thus, if you think long term - our races only choice will be to travel to other stars and planets to ensure our survival.

Programs like this will better prepare us for the road ahead.

Re:Massive waste of money

[mclaincausey]

First of all, exploring the moons of Saturn or Jupiter affords us no advantage in finding a new home whatsoever. It is scientific discovery for the sake of scientific discovery with few practical applications, and therefore, no essential relevance. I love scientific and intellectual pursuits, and think we should follow them when possible--but this is impractical given our limited resources.

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.

Re:Massive waste of money

[the_2nd_coming]

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!!!!

Re:Massive waste of money

[Zebra_X]

#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.

Re:Massive waste of money

[Anonymous Coward]

The massive waste here is that there are so many people who have no clue in this country. The reason we have personal computers and half of the plastics we have is the space program. No, it would not have happened without it. Get over yourself. That we should spend the money on more pressing concerns at home is just a false cry by those who would rather not spend the money on anything. It helps gain support among those who might otherwise think you were a miser.

Re:Massive waste of money

[Anonymous Coward]

This platitude is marked "Insightful"? As if every sententious alogical couch potato back to Cain hasn't muttered this infamous sophomorism? Sheesh.

Oh yes, absolutely. Let's wait until no human ever commits an evil deed, everyone earns over the median income, and all our children are above average before we explore the cosmos. Great idea. Insightful, even!

Re:Massive waste of money

[Anonymous Coward]

> I'm curious about the solar system, but am more concerned with dealing with the immediate crises facing us here on the Third Stone.

So am I. That's why I want to leave.

Re:Massive waste of money

[mclaincausey]

#1 - Not immediately no.

My point exactly.

#2 - This propulsion system has everything to do with getting us to planets within our solar system.

You haven't made the case for this being an immediate concern.

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.

A collapse is entirely likely, and it has very nearly happened before. Several years ago, if it hadn't been a holiday in the Asian markets, due to a glitch in the very dangerous currency speculation markets on which our global economy is now based, it would have happened. "Things have a way of sorting themselves out" is a statement of Bushian ignorance.
Our economy is in many ways a petroeconomy. Now that we see oil passing its peak production, and have massive debt and foundering Third World markets, we must be very careful. People were "managing the markets" in 1929 too.

As far as threats to the world: Global Warming - perhaps by the end of this century this will become a problem.

Another dumb statement. Are you so familiar with the ins and outs of the ecosphere and the weather system that you can definitively say what the effects of global warming, or even a butterfly flapping its wings, will be? No, you're not. This is a problem that must be fixed. It takes research, and therefore money, to look at alternative fuels and ways of restoring the ozone layer. This is a problem that we are more likely to solve, or at least alleviate, sooner than interstellar travel or interplanetary settlement. It doesn't have the panache or the military-industrial interest, so it gets ignored.

Overpopulation is another interesting one. Did you know that densely populated areas are showing a decline in the birth to death ratio?

There's no sign of decline in overall population, so we're going to have to start investigating colonizing the sea, harvesting kelp, and making agriculture and birth control more universal, instead of letting agribusiness continue to fuel the population boom. Gonna take money. I never suggested "throwing money" anywhere: I'm suggesting careful research.

Terrorism? How is that an immediate threat?

Silly question, let's just ignore the elephant in the room. Terrorism could not only kill millions of people, it could wreck the economy. I should't have to answer such an obvious question.

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.

I agree, but if we are going to start now, it's going to take money. That's why I think it's foolish to proceed with Prometheus.

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.

Did I tell you what to do with your tax dollars? I could have sworn I said "I wany my tax dollars..." It's my right as a taxpayer to say what I want done with my money. Obviously the government usually doesn't listen, but I tell them anyway.

they lack the desire. If they wanted to save it - they would.

Well, that's not encouraging either.

Columbia broke up on re-entry.

Touche, I should have specified that. Fact is, too many fuckups for them to be sending nuclear materiel up.

Not with people like you who need a clue stick to the head, no. Do you think the technology to terraform and settle Mars is just going to appear out of no where? How do you propose that we migrate people from earth to mars? Eight at a time on ships that take months to get from one planet to another? Probably not.

The technology to terrafo

Re:Massive waste of money

[mclaincausey]

All you AC's are using straw man tactics and inflammatory bile instead of entering the debate with intellect. The argument isn't that we should attain perfection or solve problems before looking to the stars, it's that we have immediate and dire circumstances that we have a higher probability of deferring if we address them than we do of escaping them to outer space in time. Our survival as a species depends upon us making the right decisions, and I don't think this is one of them. If we had unlimited resources and a better safety record, I'd totally be behind this program. But we don't. Thoughts (i.e., not invective bullshit)?

Oh you mean W2k-style power management?

[leonbrooks]

You know, the "shut down the USB hub because we can, then wonder why we never get a keyboard or mouse interrupt" style of power management? Except that in this case the keyboard is, like, tens of millions of kilometers away and there's nobody around to rip out the power cord for a few seconds when the wheels eventually do come off.

Oh, wait... maybe the aliens can do that for us?

I bet the next major W32 LAN virus author would also be so pleased to know that his software is running a billion-dollar satellite out there, somewhere, although maybe not so pleased at the van-load of scientists who rock up from the nearest earth station shortly thereafter with hot soldering irons in their hands and cold looks in their eyes.

FYI, everything's a module these days. If they forgot an important bit, they'd just rebuild the appropriate module (if necessary), then remove and re-insert it.

Re:Oh you mean W2k-style power management?

[uberdave]

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.

Re:Oh you mean W2k-style power management?

[Anonymous Coward]

Ofcourse, it doesnt help if the timer runs on ME.

Re:Oh great - It's a question of size really...

[Short Circuit]

The atmosphere tends to absorb stuff with energy levels equal to or greater than X-rays. That even extends downwards a bit into UV.

There's also an article in this month's Scientific American about how cosmic ray absorption might be triggering lightning cascades.

Real reason for this development

[Anonymous Coward]

work is to provide nuclear power capability for military systems in space. Under applicable treaties, the U.S. can't legally develop space-borne reactor technology for military applications using DoD or similar (i.e., 'black') funding sources. Exceptions apply to reactor technology developed for and/or by scientific endeavours, so NASA can develop this technology in the clear. JIMO will be a cool mission, to be sure, but make no mistake, the boys in black are the ones underwriting this and waiting for the results.

Re:Real reason for this development

[Anonymous Coward]

Except it is not even "in the clear." A significant amount of development of the Prometheus reactor will be classified. The Naval Reactors program is a very secretive group. How this system will launch with proper public scrutiny is beyond me.

Re:Real reason for this development

[spauldo]

I'm unsure on exactly why the "boys in black" would care about nuclear reactors in space.

I mean, nuclear weapons, sure, but reactors? We're not going to declare war on the moon anytime in the next 50 years, and by then we'll have the space elevator so we can put big reactors in space.

OK, offtopic, but....

[Penguin Follower]

exactly which app is that screen shot from? I gotta know! :)

Re:OK, offtopic, but....

[mcelrath]

Dunno, but you have to see the Babylon 5 total conversion for Freespace 2.

Yes, you can play on linux!

Excuse me, I have to go wipe the drool.

Yes, I've played all the way through both of the missions (using wine). The linux client has a couple crasher bugs that need fixing.

Re:OK, offtopic, but....

[WombatControl]

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.

MOD PARENT UP!

[SUB7IME]

Project Orion is sweet - mod parent up!

Stargate

[outriding9800]

I could not find anything about the asgard shields. Can someone post a link to them ? Thanks

Re:Stargate

[iowa119900089]

So "going to Jupiter" means that we really need to get some ships ready for the impending Wrath attack fleet. I think I'll go ascend now.

Re:Stargate

[Hinhule]

Please don't do that, you'll get kicked out in a year and it will be a awkward situation getting rid of your replacement.

Re:Oh great - It's a question of size really...

[__aaxtnf2500]

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.

A fistful of rebuttals...

[uberdave]

1. Although the mass is higher, the mass per unit power is probably a lot lower. In other words, to provide the same power using solar panels or batteries would likely be a lot more massive.
2. There may be a certain level of radiation, but the thing about spacecraft is that they can take up a lot of space. Every time you double the distance from the reactor, you cut the radiation by a factor of four. So, you can put the equipment, or the reactor, on the end of a long boom.
3. Nuclear subs prove that humans can live beside reactors for long periods of time without undo difficulty. (See above comment about lowering the radiation hazzard.)
4. Failed launches do not spread nuclear waste anywhere. Nuclear fuel is specially contained to survive launch accidents, as has been shown in the past. Also, NASA's launch facilities and direction guarantees that any debris will fall into the Atlantic.
5. Automating a nuclear reactor is probably less complex than operating the craft itself. The reactor has only one task to do: produce power. Automating the spacecraft involves orienting sensors, buffering data, performing course corrections, monitoring the AE-35 unit [grin], etc.

Fusion does have a long way to go, and I'm pulling for the He3 fusion mentioned on Slashdot before. Cold fusion is likely a statistical error. At least most nuclear physicists seem to think so.

Re:A fistful of rebuttals...

[Anonymous Coward]

Also, NASA's launch facilities and direction guarantees that any debris will fall into the Atlantic.

I for one welcome our mutant cod overlords...

Re:A fistful of rebuttals...

[Anonymous Coward]

Cold fusion is likely a statistical error.

No, it's a logic error. You do a complicated chemistry experiment involving hydrogen and get a lot of heat out. But zero neutrons and zero high-energy gammas. What are your choices for probable explanation?

1. I screwed up the experiment, didn't insulate stuff right, connected the black lead to the + terminal by mistake, et cetera and so forth.
   
2. I didn't think of all possible chemical reactions. Some reaction is going on that lets off a fair amount of heat. . .um, like hydrogen burning in air. . .
   
3. Whoa! I've discovered a new form of nuclear fusion that doesn't emit any neutrons or high-energy gamma rays! Patent Office here I come!
   

If you picked #3, then you're ready to apply for your first research grant in cold fusion -- to the Marahishi Quantum Healing Institute, 'cause the NSF will laugh you out of the FastTrack. . .

Re:A fistful of rebuttals...

[uberdave]

Right. I should have picked a better word. I guess it was because the last time I heard cold fusion being debunked they were talking about margins of error.

Re:A fistful of rebuttals...

[norkakn]

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.

Heat Engine Efficiency

[mosb1000]

Of course, the efficiency is related to the temperature of the cold reservoir being used and the temperature of the working fluid when it is heated. If you can heat it to 800K (typical for a HTGCR) )and then cool it to 3K (sometimes called the temperature of space), you'd have nearly complete efficiency (apart form the inefficiency of the turbines, that is). Obviously, on the earth there are practical reasons you cant get the temperature that low (you're pretty much stuck with 300K), but in space if you angled the radiators correctly and were relatively far form the sun, you could probably get it down to say 150 K, and have maybe 70% efficiency, rather than the 50% you'd get with a HTCGR on earth.

They stole the name of my web site

[SpiritHex]

I used to run "Operation Cyber Prometheus", at ocprometheus.org, a tech web portal (circa 1996) featuring links to any tech material that existed on the net, which I left to die when search engines started getting more popular and updating links manually grew too tedious a process :)

If you check that url, you'll see someone else registered it to capitalize on the name, it still exists. And guess where hardOCP got their name from too ;)

And now Project Prometheus? Coincidence? I THINK NOT! They stole my name! Well I guess Project Prometheus is a rather generic name..

Did I mention how I got Google started too? Well I'm kidding about that, former is 100% true however. Oh well, maybe someone cares somewhere.

I'm so fucking sick of people like you

[Anonymous Coward]

Ooooo! We can't do anything off planet until we solve the problems here on Earth!

IT'S NOT GOING TO HAPPPEN, YOU WHINEY DUMBASS PUSSY!

We will not solve the miseries of human nature for thousands of years. It's not going to happen. Not in your lifetime. Not in yout great grandchildren's lifetime. To put progress on hold because thee Earth is filled with morons who can't get their acts together is completely insane.

You know you could use your fucking browser..

[Anonymous Coward]

..and look it up yourself, you ignorant, demon-haunted fucktard.

Duoh ....

[taniwha]

I mean "radionuclides" ....

Gaseous Core Nuclear Reactor Rockets

[serutan]

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.

Re:Gaseous Core Nuclear Reactor Rockets

[avandesande]

just a small detail... does uranium hexaflouride have enough uranium per cross section to go supercritical? even more so with the gas.....

Re:Gaseous Core Nuclear Reactor Rockets

[jafac]

does uranium hexaflouride have enough uranium per cross section to go supercritical?

Maybe as a Bose-Einstein condensate. . .

Maintaining Cryogenic conditions in a substance undergoing nuclear chain-reaction is an excercise left for the no-bid contractor. . .

NASA must have told Bush there's oil on Titan!

[mbkennel]

that's right, George, there's rivers and rivers of LIQUID HYDROCARBONS down there, and America's got the mineral rights!

Re:NASA must have told Bush there's oil on Titan!

[CdXiminez]

That lander was European.
You'll be sharing those mineral rights with liberal Europeans who signed the Kyoto protocol...

just don't stand under it

[SiggyRadiation]

Like LSD: the only way it can kill you is if you'd be hit by a truckload of it.

Re:just don't stand under it

[cheekyboy]

or if you started to drive the truck

Socio/psycho aspects of this

[Eminence]

• The potential ROI on space travel is huge, but it's also very long-term.

Hm it's also interesting how the concept of a family in the society and changes in it affect attitudes here. Since we generally don't see our families now as clans going on for centuries across generations any ROI that is likely to happen after your death is not worth much trouble. I guess people who have kids have a slightly different view, but even then, I think most people concentrate at things that will happen within the span of the life they're living now. It has also much to do with the assumption, deeply rooted in our culture, that we have only one single life.

If you sum all that up there are a lot of psychological incentives to concentrate rather on stuff that would bring fast, tangible results within one's lifespan so that he can enjoy them.

Re: "We used it in WII"

[j_w_d]

Research this some. You may be forced to conclude that the decision actually saved tens of thousands of American lives and literally millions of Japanese. I once tried researching the possibility of writing and SF novel predicated on Truman deciding not to use atomic weapons. I concluded that it could never be published. Too grim and no one wanted to read about the Soviets as the single surviving super power.

Shooting money into space

[j_w_d]

It's the politicians who make the spending decisions you should blame, and more generally, the voters who elect those politicians...

You have that right. I have talked with people who literally seem to think "all the money we have shot into space" is somehow really in orbit out there. Arguing that "all that money" was really spent right here on the ground and that we are all benefiting from the knowledge it paid for often falls on deaf ears.

Re:Shooting money into space

[cheekyboy]

wake up dude, 90% of the populace are inherintly stupid MOFOS, otherwise they would be experts in every field.

Yes mr X citizen, go read 1500 essays and spend 50000 hrs researching XYZ topic, then come back and do it again re topic #2.

Most rather just watch american idol then go to bed with their SO.

Oh come on...

[Corpus_Callosum]

Because there ain't no way the Bush White House is paying for this.

You know this is just a cover story for additional funding for UFT based antigravity craft. The people have to see something going on. It can't all be black..

Step 0...

[leonbrooks]

...is wait for it to be finished (chopped, possibly remixed from different audio if needed, possibly direct video from the screen pasted in - a job I don't envy in this case since Mark had OOImpress set for automatic advance and kept going back, rendered into a compressible format) and released. (-:

Let the organisers know that you care. Conf delegates and speakers get a CD/DVD set snailmailed out automagically, you may be able to buy and/or download a DVD (or just the video) later as well.

Anyone dumb enough to fly a w2k-controlled reactor

[leonbrooks]

...is also dumb enough to make the watchdog timer a USB device.

Re:The thing to do with Uranium is...

[Fizzl]

Except that uranium is so common material, that it would be akin to basing the currency on iron. (or something...)

So what's the *acceleration* ???

[Ancient_Hacker]

It would be nice if they mentioned the acceleration of this thingy.

That's one heavy mothership to be pushed by shooting out tiny amounts of ions!

At a first approximation, the acceleration's gotta be somewhere under 0.00001G's, which makes the whole scheme rather slothful and boring.

And if there's going to be pumps and turbines involved, how're they going to keep the thing from spinning wildly in several axes? Surely not with reaction thrusters. The more I think about this thing, the more it looks like some gigantic delayed April Fools joke.

Project Orion - a REAL nuclear spaceship

[hairykrishna]

Give me projec torion anyday:

http://en.wikipedia.org/wiki/Project_Orion

There's some thing much coooler about the idea of riding into space on top of a series of A-bomb explosions. Bit of a public relations nightmare of course but you can't have everything.

Prometheus

[Anonymous Coward]

Where did the name come from?
Are they:
a) planning on stealing fire from the Gods?, or
b) expecting it to get it's liver ripped out?

Re:Prometheus

[spauldo]

They expect to have their funding approved and rejected over and over again.

Hence, the liver metaphor seems to work best.

death due to life.

[cheekyboy]

Geee, doesnt life itself cause death, lets outlaw life then.

Why is everyone turning into pussy little gay girls, get some damn guts. Life is cheap, risk is easy, payoff is huge.

Just think of all the badass pollution/lead contamination, especially in LA/Sanfran where they build new condos over old waste disposal sites from the 60s that have tonnes of crap burried, but no one cares because local govts get some good cash from land taxes and banks get more sales and builders build more houses.

Re:death due to life.

[Gothmolly]

Nice troll, but you gave yourself away when you misspelled "tonnes". Go back to your side of the pond.

Selling nukes in space

[dpilot]

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.

Gaseous core reactors not for deep space travel?

[Richard Kirk]

Thanks for the link. Seriously fun. However, isn't this something between the conventional chemical rocket (low exit velocity, so lots of momentum per unit energy, but you run out of stuff to chuck out the back end quick) and the ion drive (tiny thrust for the wattage, but the same weight lasts for ages)? The Prometheus could use the waste heat of the reactor to drive this way, but then they would have to pack extra propellant mass, which takes away the whole point. This is why they have radiative heat sinks instead of evaporative cooling. I don't think this is the sort of thing that would leave its motor on for the months it would take to get to Mars, but it could accelerate a large craft for some hours, and decelerate it at the other end, which would amount to the same thing.

With a nuclear source and/or solar panels we can get lots of energy. The problem is always getting enough mass to check away to get momentum. There is not a lot of stuff out in space, but there is enough to drive a solar sail. If we can trap a bit of this, then we can use this as propellant. I dimly remember a proposal for a craft with an electromagnetic scoop for interstellar hydrogen (the Daedalus, I think it was called). If we can scoop enough to keep a gaseous core reactor busy, then we would be cruising indeed.

PS.

If it blows up in the atmosphere, the uranium might not be a huge problem, but the fluorine you get when the UF6 splits up in the UV would do in the ozone layer something rotten. Be prepared for considerable community service slapping factor 30 suncream on angry emperor penguins.

Yes, you are

[wiredog]

and not just today, either.

money is cheap, trillions are lent each year

[cheekyboy]

Dude, look at the M3 money supply, how much trillions is lent out each year just for housing/credit cards. (http://financialsense.com/resources/fed/moneysupp ly.htm)

Those old farts who own pension funds dont mind lending out trillions to teenagers credit cards and 20somethings home loans that might never be paid off, just so grandma can keep living cheaply. But if you want real investment, nooooooooo, because all those old people will die before they see a return, pitty, trillions of wasted money all going on immediate returns just so grandma can get her titanium hip.

Dont forget, the FED creates tonnes of new money out of thin air, they could easily say, "well lets print 1000 billion in Tbills , sell em at 5% and give the cash to NASA"

Re:money is cheap, trillions are lent each year

[Rich0]

Dont forget, the FED creates tonnes of new money out of thin air, they could easily say, "well lets print 1000 billion in Tbills , sell em at 5% and give the cash to NASA".

Uh, the FED doesn't set the interest rates on Tbills. The Tbill-buyer does that.

Forgive me for not knowning the exact details, but the process is something like:

I have here bills that plege to pay you $10,000 in 10 years. Anybody willing to pay $10,000 for them? No? Ok, how about $9,000? And so on.

The bills are sold for the highest price available on the market. The interest rate is essentially what you get if you put a principal value of the selling price and a P+I value of $10,000 into the compound-interest formula and solving for the rate.

If the Fed just wanted to issue a trillion dollars in tbills they'd have to practically give them away since nobody has that much money to buy them.

When the government issues $1 million in savings bonds they don't get $1 million. They get somewhat less. The more they issue, the less they get compared to what they have to give back.

Supply and demand...

Fission in space

[displague]

On Earth, we use water to cool fission reactors (right?). So in space, would they use diffusion of heat into the void to cool systems?

I hope they've played with this stuff in gravity free environments. What would happen if you had the reactor on before breaking free of gravity? Would the change be disruptive to the plasma?

( I'ld rather have the Prometheus from SG-1 )

Re:Fission in space

[Anonymous Coward]

On Earth, we use water to cool fission reactors (right?)

We have used water, CO2, He, Na, NaK, air, and other things too.
Space reactor designs have focused on liquid metals (e.g. Na) and gas (He). A large radiator is needed to radiate waste heat to space.

I hope they've played with this stuff in gravity free environments.

Reactors have flown in earth orbit before. The USSR flew many, and the US has flown 1.

Prometheus: a bad choice of name

[Traf-O-Data-Hater]

From NASA's overview:
"Prometheus brought down the gift of fire from the heavens to humanity".
That will go down well with the environmentalists... it does not inspire much confidence about keeping this (nuclear) fire up there instead of down here, does it?

Re:Prometheus: a bad choice of name

[TheRealStubot]

Yeah, Prometheus was also punished for his deed. Chained to a rock, so a huge buzzard could eat his liver (!) every day, which would grow back every night... byproducts of all the plutonium released into the atmosphere, I guess.

Really efficient orbits using Lagrange points

[Dr. Manhattan]

Turns out there are orbits that can easily and naturally 'fall' from one Lagrange point to another. And the Lagrange points for a complicated moon system like Jupiter's intersect frequently, so you can use to very efficiently hop from one moon to another while using orders of magnitude less fuel.

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

Specific Impulse Units: N*s/kg

[radtea]

Despite the weight (or was that mass?) of immemorial tradition, the units of specific impulse are not seconds. Pounds force are not pounds mass. Giving them the same name does not allow one to cancel them, any more than one can cancel the "d"'s in a derivative.

The units of Isp are lb-f*s/lb-m, or better yet, N*s/kg. lb-m isn't even a good Imperial unit--it ought to be slugs.

Isn't it about time rocket scientists got with the 21st century?

--Tom

Re:Specific Impulse Units: N*s/kg

[Manhigh]

Specific impulse is usually "normalized" by g at earth sea level.

Exhaust Velocity = g * Isp

Therefore, Isp is uaually listed in units of seconds.

OMFG! EVIL NEO-KKKON PLOT TO POLLUTE

[Anonymous Coward]

. . . the solar system with RADIATION!!!

Damn you Chimpy Bushitler!

A fundamental error

[GMFTatsujin]

Guys, I'm here to tell you that this project is doomed to failure. Nothing to do with the science involved...

It's the name.

PROMETHEUS? Why not name it the Titanic Initiative while you're at it? Or the Pandora Project? Or maybe pay some homage to the Kobayashi Maru? (You know: that one ship that was TOTALLY FREAKING DOOMED and there was NOTHING you could do about it.)

This is the problem with scientists: they fail to think *dramatically*. It is only sensical that a project of this type will open a dimensional rift to Hell, mutate the human race, and/or ignite the core of the Earth in a catastrophic conflagration that will blow the Moon out of orbit.

When are we going to learn? Never, *never* name a first-of-its-kind endeavor after any legend that concludes with the high price of human hubris. Likeways after anything that will be considered ironic when it inevitably goes down in flames.

Re:A fundamental error

[Anonymous Coward]

So Icarus is right out, then? Pity.

Re:A fundamental error

[Anonymous Coward]

Why not "Death Star", then?

Re:Gaseous core reactors not for deep space travel

[Anonymous Coward]

You're speaking of the Bernard ramscoop. EM funnel several light-seconds across funnelling hydrogen and other fuseable elements into a scoop to use as a reactor mass.

Re:Gaseous core reactors not for deep space travel

[jafac]

It's called a "Bussard Ramjet" after the guy who dreamed it up.

Better still, was an idea for a variation on the Solar Sail, which creates a magnetic field from an onboard power-source. Solar-wind drag on this magnetic field is what then propels the craft - which solves the propellent problem. As with a "conventional" solar sail - accelleration is very low (as compared to the very low accelleration of today's ion-drive technology, akin to the weight of a sheet of paper) - but top speed is limited by the speed of the solar-wind, which is higher than the top speed attainable by ion-drives by a couple of orders of magnatude. . . which is also, higher than the top speed attainable via chemical rockets by another couple of orders of magnatude (ie. you can't travel any faster than the speed of the stuff you're chucking out the back).

We already stoped

[Ironsides]

The US hasn't made a nuclear weapon in over a decade. Read the list. We just keep up maintainence on the current ones.

Not exactly...

[mbessey]

"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.

reincarnation

[Hyperhaplo]

.. yes.. but when it all goes to hell you know there's always a group of people waiting to fish you out of the deep water/fire/space

It's a pity they don't care at all.. for all the power/s they have.

Much like any government really..

Prometheus

[Anonymous Coward]

Am I the only one to remember that Prometheus after giving the fire to the humans was punished by the god.

From Wikipedia:
"Zeus [...] had Prometheus carried to mount Caucasus, where a vulture or an eagle named Ethon [...] would eat out his liver; it would grow back each day and the eagle would eat it again"

It would be quite easy for any opponent to the subject to make a similarity that after sending it the economyy would have to suffer for 30'000 years.

Nils

Fighting in space

[Nutria]

with the distances involved

Just like real world military aircraft need "homes", either land bases or aircraft carriers, military space fighters will need "spacecraft carriers" or space stations (either orbiting planets, or deep space, a la Star Trek).

and the lack of a "top" speed there is not going to be much dog fighting.

Lack of "top speed"??????

Huh?

Anyway, this is all moot until the requisite power source is discovered.

It's moot anyway, I think. Space is just so hostile, building small fighter craft would just be too expensive.

Re:Fighting in space

[Retric]

I don't think it's an isue of building small fighter's will cost to much I think larger ships will get to pull just as many g's as small ships so it's pointless. Let's say your building space station X and it's a target if it can't move at all I can just take a 10kg rock get it up to say 1/10c and pop goes space station. The only way to stop this is to not be where they thought you would be when they lauch the thing.

At to the lack of a top speed well on earth it's easy to pull 10 or 20 g's if you bank hard but you can't keep speeding up at 10 g's for vary long thus you end up dog fighting. But to pull 10g's in space I need a huge rocket that let's me pull 10g's now at that point I can just use that rocket to go 10g's for as long as I have fule so if I can now go at such speeds that nobody can catch me.

Think of it this way, if I can go 10g faster than you I get to be 1km from you in 5seconds, 4.9km from you in 10, 11km from you in 15 and 176.4km from you in 60 seconds but now in the air I can do that by banking hard and or diving but in space it's all about the size of the rocket so I could do that going in a straight line. Also in space there is no need to put the guns on the front of the ship so I can have rockets pointing in all directions and it works just as well. So why not just do a flyby at say mach 3,000 fire everything I got before I get to you and keep on going you don't get to catch me if I am going mach 30,000 and you start pulling 10g's I get to pull 10g's and I sill pull away from you at mach 3,000.

Last I checked fusion will let you pull 1g+ for days so you could easly do this type of fighting inside a solar system using tech that's well within our reach.

No, Tupelovs are not that bad

[leonbrooks]

The US dudes making the decisions thought they were, which is what matters. They also thought they'd be cute about it, which was not a particularly bright approach to people who have been immersed since birth in a culture where multi-level messages and indirection are the norm.

I think the Tupelov-fearers would have had massive coronary palpitations when Mark got to the fuelling-tech anecdote, though. (-: