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Update on Project Prometheus
Aglassis writes "It appears that NASA is not backing down from their nuclear space initiative. Project Prometheus has recently started a new web page (under JPL) and NASA is finishing up a period of public comment (last session today). Currently Northrop Grumman is contracted to begin preliminary design of the spacecraft until 2008 for NASA (the reactor will be built by the Department of Energy's Division of Naval Reactors--the folks who control all US submarine and aircraft carrier nuclear reactors). Early specs are that it will be 60 meters long, have a 30,000 kg mass, use a 100 KW reactor using Brayton cycle gas turbines, be powered by ion thrusters with a 7000 second specific impulse, and have a science payload of 1500 kg. Early mission plans for Prometheus 1 (Jupiter Icy Moons Orbiter) indicate that the spacecraft would orbit Callisto, Ganymede, and Europa individually, and perhaps have a lifespan of about 20 years."
Disclaimer: I am not a rocket scientist.
In Soviet Rush, today's Tom Sawyer gets high on you.
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?
than the real progress NASA makes.
IMHO, it's a real shame projects like these aren't far more international in scope, open to all bidders, and funded from a futures type trust and traditional venture capital funding, as well as grants and taxes. Heck, most of these projects will pay back in spades if the new technologies were only properly licensed.
It simply amazes me how we have so many business geniuses, but not one of them has even considered space as the next new continent. What ever happened to good old American ingenuity and initiative, eh? Why have we apparently just given up our collective dreams of space exploration and development? Any one care to explain?
Words to men, as air to birds.
"It appears that NASA is not backing down from their nuclear space initiative."
It'll still be lifted off the ground by chemical rockets. What happened to NERVA?
That's 10 times the best chemical engines ever designed.
The politics of why they even bothered to look, and what was actually found, are another subject/debate unto themselves...
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.
Easy. We rename Project Prometheus to "Project Hubris".
That said, I'm happy it never really materialized. Having a universe with a human population spreading effectively in it summons an eerie image on a spherically expanding brain-tumor to my mind...
http://isbndb.com/d/book/project_orion.html
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.
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>
If you disagree, post your argument. (-1, Overrated) isn't your personal censorship tool for views you don't like.
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.
The real Captain Avatar is a fictional character, so I suppose he doesn't mind if I impersonate him.
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?
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. . .
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.
"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.
No, the correct answer is: the US is already a declared nuclear state and the continued manufacture of nuclear weapons is therefore not a violation of the Non-Proliferation Treaty, which pretty much says "If non-nuke states don't build their own bombs, nuke states will help them build reactors." What Iran is doing is outside the bounds of the treaty.
Besides, when you already have several thousand fusion warheads, why build more?
As an anti-nuke nut, I'd like to say that I'm fine with NASA using nuclear energy.
I'm just not fine with Haliburten using it.
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.
The Soviets even reused RTGs salvaged from blown up missions because thay were in usable condition after plumeting from the sky and it was cheaper than building new ones. Any US designed nuclear reactor will be just as robust (unlike Topaz).
I am becoming gerund, destroyer of verbs.
"when you take a small mass of radioactive material that gives off lethal amounts of radiation and spread it over a large geographic area you cannot get a lethal exposure. "
It really doesn't work that way. Highly-radioactive chunks of metal of various sizes hit the ground after Cosmos 954 crashed. Several of them could have delivered a lethal dose to a person whio handled them without proper protection.
Here's one reference
And another reference
That talk about the potential lethality of some of the recovered fragments from the satellite. Keep in mind that nobody knows how many of the fragments that hit the ground were actually recovered.