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ToSeek
2003-Jan-19, 02:07 AM
White House Go-Ahead on NASA Nuclear Prometheus Project (http://www.space.com/businesstechnology/technology/nuclear_power_030117.html)

Word is that President Bush will be announcing in his State of the Union address that NASA will be receiving significantly increased funding to support research into nuclear propulsion, which could make crewed missions to Mars much easier.

So maybe there will be human beings on Mars in my lifetime, after all.

Jigsaw
2003-Jan-19, 02:59 AM
Wow, I saw that article on space.com and I came hustling over here, I thought there'd be a two-page thread on it already. Where IS everybody? /phpBB/images/smiles/icon_biggrin.gif

So, what does this mean?

Spin control

NASA spokesmen were busy calling into question details revealed in a January 17 story in the Los Angeles Times. The story stated that the Bush Administration has given an agency go-ahead to build a nuclear-powered rocket. Not only would the project make human travel to Mars feasible, the story suggests, work on the nuclear space rocket would be a boon to California aerospace firms.

< snip >

NASA spokesman, Don Savage, said that the Los Angeles Times story misstated some elements of what O'Keefe discussed regarding the agency's Nuclear Space Initiative (NSI). NASA formally requested the newspaper for clarification of several points in the story that could be misconstrued, he said.

NASA spokesman Glenn Mahone acknowledged that O'Keefe did talk generally about the upcoming State of the Union but did not make a prediction that Bush would use it to make any NASA-related announcements.

< snip >

"O'Keefe didn't say that there would be announcement in the State of the Union concerning NASA. He doesn't know what's going to be in the State of the Union and certainly wouldn't get out in front of the President," Savage responded to SPACE.com.Are they waffling? Are they issuing a big, "Um...not really?"

Did the reporter just jump the gun?

John Kierein
2003-Jan-19, 03:13 PM
Nuclear power cause cancer? Cancer grows faster in space.
http://www.space.com/missionlaunches/sts107_update_030117.html

A.DIM
2003-Jan-19, 05:53 PM
I see this as a sort of retort, what with increased talk about nuclear abilities, Iraq, N.Korea, et al.

Cool though, is the idea of humans walking on Mars in our lifetimes.

Rodina
2003-Jan-19, 06:17 PM
I think the Space.com article (I read it last night when I was sleepy) mentions, in part, that the NASA proposal is, in part, meant to improve the efficiency of RTGs so you can get more power out of the same amount of Plutonium and my guess, if it is part of a larger nuclear initative, this administraion will want to lead with that.

"I direct NASA to research and improve its nuclear technology so we can make safer and more successful probes to the outer planets" is better PR than

"Let's build a solid-core nuclear rocket"

I'm for both, mind you, but I think part of this spin on the LA Times report is that they don't want the story to be largely "nukes in space" they want it to be "improving the safety of power sources for space probes"

g99
2003-Jan-19, 08:46 PM
I am tottaly for any kind of Space reaserch and tech. The only problem i have is that i Live in Florida and if that think blows up during a launch, well lets say i won't need a flashlight to go to the bathroom anymore at night. /phpBB/images/smiles/icon_smile.gif

Glom
2003-Jan-19, 08:58 PM
The group has campaigned against the launch of Galileo and Cassini missions in past years. A "No Nukes in Space Protest Vigil" is slated in early February, outside a symposium on nuclear space power to be held in Albuquerque, New Mexico.


Anarchist nurks!

How do they feel about the Sun then?

I'd personally prefer to have the limited supply of fissile material available being used to power scientific mission millions of kilometres away then have it used to make nuclear bombs.

Any hawks that try to use this to develop space weaponry will have to face the rest of the world over their breach of The Outer Space Treaty.

<font size=-1>[ This Message was edited by: Glom on 2003-01-19 16:09 ]</font>

Glom
2003-Jan-19, 09:06 PM
On 2003-01-19 15:46, g99 wrote:
I am tottaly for any kind of Space reaserch and tech. The only problem i have is that i Live in Florida and if that think blows up during a launch, well lets say i won't need a flashlight to go to the bathroom anymore at night. /phpBB/images/smiles/icon_smile.gif


Do you regularly have blackouts in Florida. In Britain, we have mains electrics.

Still, I think it could be a good thing. It would be more energy efficient. Lower electrical costs.

Mind you the light pollution would radically increase whenever someone went outside. Imagine trying to get dark adapted for a night out observing only to have it ruined everytime you look at your hand.

That's why you've got scientists looking at that sort of thing. If you left it up to me, it would be no good.

g99
2003-Jan-19, 10:38 PM
I think a nuclear powered rocket or space station would be very good. It could stay up there for much, much longer than normal. I just hope they have greater safety measures on the launches.

We only get lots of blackouts during the summer where it rains alot (at 4:00 P.M. every day to be picky (within a half hour or so). There are lots of thunderstorms and since we have such a high ground water level, we cannot bury lots of power lines. So most are above ground, thus a lightning strike, and boom, power is out for a few hours. But otherwise, i am just too lazy to turn on the light and end up stubbing my toe on my bedside table. /phpBB/images/smiles/icon_smile.gif

Argos
2003-Jan-20, 01:36 AM
On 2003-01-19 15:58, Glom wrote:

Any hawks that try to use this to develop space weaponry will have to face the rest of the world over their breach of The Outer Space Treaty.



I´m affraid that treaties aren´t worth the paper they´re written on, these days [regrettably]. But I favor the development of nuclear technology for space propulsion, provided that we can rely on adequate safeguards.

<font size=-1>[ This Message was edited by: Argos on 2003-01-19 20:43 ]</font>

Tuckerfan
2003-Jan-20, 05:02 AM
Go, Georgie, go! Let's do it! I wanna walk on the Moon before I die! (Heck, I'd rather walk on Mars, but I ain't gonna be greedy about it.)

daver
2003-Jan-21, 01:40 AM
On 2003-01-18 21:59, Jigsaw wrote:
Wow, I saw that article on space.com and I came hustling over here, I thought there'd be a two-page thread on it already. Where IS everybody? /phpBB/images/smiles/icon_biggrin.gif
...
Did the reporter just jump the gun?



I read a couple of articles; as far as i can tell, nobody who knows anything is saying anything. One article (maybe space.com) said something about tripling the speed available from space probes, and then went on to equate this to reducing the transit time for a manned Mars mission from six months to two months [the math here looks pretty suspicious]. Another looked like the proposal was going to be for better RTGs.

Colt
2003-Jan-21, 04:25 AM
I am glad to see that NASA is finally getting in gear about nuclear propulsion technologies. NASA developed workable nuclear propulsion many years ago but was abandoned for one reason or another. -Colt

daver
2003-Jan-21, 06:39 PM
On 2003-01-20 23:25, Colt wrote:
I am glad to see that NASA is finally getting in gear about nuclear propulsion technologies. NASA developed workable nuclear propulsion many years ago but was abandoned for one reason or another. -Colt



I had seen a post claiming that DUMBO looked to have superior performance to NERVA. I looked around on the web a couple months ago and found a few papers on DUMBO--it looked pretty nifty. It looked like they might have a hard time shutting it down once they started it up, but i'm not a nuclear engineer; they likely had some method.

No, i don't really think the project was shut down because of fears of a trademark infringement lawsuit from Disney.

Ilya
2003-Jan-21, 07:57 PM
Sorry, but the media may have blown this out of proportion:

http://www.spacedaily.com/news/rocketscience-03a1.html

If the above article is correct, Bush's initiative is limited to unmanned probes.

RafaelAustin
2003-Jan-22, 02:45 PM
According to this Wikipedia (http://www.wikipedia.org/wiki/Nuclear_thermal_rocket) article, nuclear thermal rockets have problems with vibrations. The fuel rods are so fragile that they tend to break up.

Does anyone here know if these type problems have been solved or are there any other practical problems that stop the development of craft large enough for manned missions?

Avatar28
2003-Jan-22, 06:59 PM
On 2003-01-22 09:45, RafaelAustin wrote:
According to this Wikipedia (http://www.wikipedia.org/wiki/Nuclear_thermal_rocket) article, nuclear thermal rockets have problems with vibrations. The fuel rods are so fragile that they tend to break up.

Does anyone here know if these type problems have been solved or are there any other practical problems that stop the development of craft large enough for manned missions?


What we need to look at is fusion propulsion. Then you don't have to worry about fuel rods That is still probably a couple of decades away at least. But there are other possibilities that may work sooner.

VASIMIR (http://www.ornl.gov/ridgelines/rocket.htm) is one.


The VASIMR’s plasma, which consists of helium ions and electrons, is generated by a helicon plasma injector and confined and shaped by high-temperature superconducting magnets. The plasma would be guided through a rocket chamber formed by a magnetic field and further heated by rf waves at ion cyclotron frequencies.

“The helium can be heated to very high temperatures, which provides a directed, very high-velocity exhaust plume,” Milora says. “The magnetic field is like a hose. As the helium ions come down the hose, spinning at the cyclotron frequency, we jack ’em up further with the rf power tuned to that frequency.”

What comes out of the rocket’s magnetic nozzle is 1 million degrees hot, at a velocity of 70,000 meters per second.


A Gas Dynamic Mirror Engine (http://www.space.com/news/antimatter_engines.html)is another.



NASA engineers are developing a radically new type or rocket engine that harnesses the power of stars to cut travel time to Mars, for example, from the current nine months down to three months. Called the gas-dynamic mirror engine, it traps and heats gas to temperatures as sizzling hot as those found at the core of the sun. That's hot enough to allow for nuclear fusion by combining lighter atomic nuclei into heavier nuclei.

Within a few months, a six-foot long model of the engine will be fired-up by injecting a superheated gas confined between powerful magnets at either end of the engine. Within a couple of years, the engineers hope to achieve a sustained nuclear fusion reaction in the hot plasma.


With any luck, either or both of these will get new funding as well. If we spent even a fraction of what we spend on the military on things like fusion research, I imagine we would have working fusion reactors and propulsion by n ow.

daver
2003-Jan-22, 10:16 PM
On 2003-01-22 13:59, Avatar28 wrote:
...
With any luck, either or both of these will get new funding as well. If we spent even a fraction of what we spend on the military on things like fusion research, I imagine we would have working fusion reactors and propulsion by n ow.


I don't. Nuclear fusion is hard; sustained nuclear fusion might be impossible outside of a sun. Implosion fusion could be the best bet, and it's not all that clear that more money would speed up the progress on that.

xriso
2003-Jan-23, 05:46 AM
Nuclear rocketry sounds like a great thing. How do nuclear technologies for launch and space-navigating compare to conventional ones?

Glom
2003-Jan-23, 05:21 PM
As with all things nuclear, you get more bang.

Nuclear reactions involve a lot more energy than chemical reactions so for a given mass of fuel, you can get more energy.

The Saturn V had the energy equivalent of a nuclear bomb locked up in its tanks, so what took over 100m of rocket to do with chemical engines, could be done with probably about a Redstone sized rocket.

tjm220
2003-Jan-23, 05:29 PM
On 2003-01-22 09:45, RafaelAustin wrote:
According to this Wikipedia (http://www.wikipedia.org/wiki/Nuclear_thermal_rocket) article, nuclear thermal rockets have problems with vibrations. The fuel rods are so fragile that they tend to break up.

Does anyone here know if these type problems have been solved or are there any other practical problems that stop the development of craft large enough for manned missions?


What about this fusion (http://www.newscientist.com/news/news.jsp?id=ns99993294) design?

daver
2003-Jan-23, 10:26 PM
On 2003-01-23 00:46, xriso wrote:
Nuclear rocketry sounds like a great thing. How do nuclear technologies for launch and space-navigating compare to conventional ones?


Right now i don't know of any serious nuclear launch proposals (which doesn't say much--i haven't been following). For launch, you want high thrust; specific impulse isn't as important. In fact, for part of it you might want fairly low specific impulse, just so your launch pad doesn't vaporize.

The proposals i've seen involve exhausting the output of fisson reactors into the open air, or detonating nuclear bombs under the ship. The PR campaign that lets you launch is going to be more expensive than any other aspect of your design.

In-space fission drives come in a couple of varieties--one uses the reactor as a power source to run a more conventional drive (like ion). The other uses the reactor to heat your working fluid (nuclear thermal). There's another variant, the nuclear salt rocket, which, if it only worked, would be the nuclear fuel of the interplanetary space operas (high thrust, high Isp, insanely radioactive).

Nuclear reactors for ion drives are pretty much what you'd expect--low thrust, high efficiency engines, good for outer system stuff.

Nuclear thermal are higher thrust, lower efficiency (but better than chemical) engines. For a manned Mars mission, i'd guess nuclear thermal would fit the bill better.