VASIMR

[Sky Captain]

To prevent spreading of a nuclear fuel in case of rocket crash it can be put into strong containers designed to withstand a rocket explosion like is already done with RTG`s. Also one can choose a launch site that allows to launch over an ocean or desert (like is already done with most space launches).

Anyway a rocket is going to be a bigger danger than it`s nuclear fuel payload in case something goes wrong. No one is going to ban a space launches because there is a remote chance a rocket malfunctioning and hitting a populated area. Also there are no other options. If we are going to start a major space program and launch large manned deep space missions nuclear power is the only practical method to do it and only way how to get nuclear reactors in orbit is to launch them atop rockets.

 

[RisingFury]

I'm not against nuclear reactors in space... this discussion has only been started cos I said that we won't see anything in the near future. Yes, 20 years into the future, a VASIMR powered by a nuclear reactor might be delivering supplies to a Moon base... but let's not get overexcited and think we'll be heading to Mars in 10 years.

 

[francisdrake]

I wonder if todays politicians would approve a program involving launching nuclear reactors into space, no matter how good the safety containment may be. I guess this aspect killed the JIMO orbiter and the Prometheus program.

As far as I remember the reactors in space were launched in the 1960s, when the risk of radioactivity was judged much lower.

Cassini had quite a bad press over here in Europe during its Earth flyby, because of the fission material in its RTGs. I heard they even raised the flyby perigeum, to reduce the risk of an accidential reentry, which could have spilled the radioactive material into the atmosphere.

On the other hand, without a decent energy source space travel will remain quite limited. Solar arrays make sense only out to Mars orbit and are good only for small consumers (like ion engines). To power a reasonable VASIMR engine would require football-field sized solar arrays.

Do you think a nuclear space program could find political acception in the US, or in Russia?

 

[pattersoncr]

[snip]
Cassini had quite a bad press over here in Europe during its Earth flyby, because of the fission material in its RTGs.

Not sure what you mean by "fission material", but RTGs don't contain fissile material or fission products.

 

[Andy44]

Besides, you're not really trying to justify the loss of life for space exploration, are you? Even if you feel that loss of life is necessary for space exploration, I don't think you felt the same way if someone close to you lost it.

Why not? We justify using STS, which has killed 14 crew members. The response to those deaths was not to give up, but to make procedural and engineering changes to prevent those failure modes from occuring again.

How many people are killed in auto accidents each month? We justify cars, anyway.

Far fewer people would be killed by launching fresh fission fuel into space in launch-proof containers than by cars. The launch really isn't the risk.

If there is a risk, it's from nuclear-powered vehicles operating in LEO or returning to LEO from deep space, which may have accidents like the Cosmos 954 reactor whose orbit decayed, causing it to crash in Canada. These accidents can be prevented by proper operational and safety procedures. In the unlikely event this does happen again, the chances of it doing serious harm to humans or the environment is small, due to the fact that these are not Chernobyl-like accidents.

When I walk through the northern Canadian forest, I am far more fearful of grizzley bears than running across a chunk of spent Soviet reactor fuel.

 

[RisingFury]

Why not? We justify using STS, which has killed 14 crew members.

And we know that BOTH of these two could have been prevented. With Challenger, the engineers on the ground produced report after report why the shuttle shouldn't fly. With Columbia, the impact was spotted and satellite images requested, but engineers again got turned down by the management. There was a choice if the management was gonna risk their lives and look where that got them.

If we are gonna take such reckless decisions in the future with nuclear propulsion, thins are eventually gonna go horribly wrong.

The response to those deaths was not to give up, but to make procedural and engineering changes to prevent those failure modes from occuring again.

And all of those could have been prevented if the management wouldn't go ahead with such reckless decisions.

How many people are killed in auto accidents each month? We justify cars, anyway.

And yet most of these deaths occur because people fail to follow rules and guidelines. Speeding, texting, drunk driving and other such failures to follow the rules lead to the vast majority of those deaths.

If there is a risk, it's from nuclear-powered vehicles operating in LEO or returning to LEO from deep space, which may have accidents like the Cosmos 954 reactor whose orbit decayed, causing it to crash in Canada. These accidents can be prevented by proper operational and safety procedures. In the unlikely event this does happen again, the chances of it doing serious harm to humans or the environment is small, due to the fact that these are not Chernobyl-like accidents.

When I walk through the northern Canadian forest, I am far more fearful of grizzley bears than running across a chunk of spent Soviet reactor fuel.

That was luck.
Radioactive material could have been spread over a populated area or contaminate food and water sources.


I'm not expecting a Chernobyl like disaster any time in my life, due to nuclear rocket propulsion... or ever. But that doesn't mean that smaller scale disasters don't count.

 

[cinder1992]

post removed: was on second page.

 

[Marcel]

Wow, I go away for a day and find a fascinating discussion going on!
My comments:
If all we can do for now is solar powered engines that's fine by me! We can go to Mars, and perhaps someday mine it or the Moon or Mercury robotically for nuclear materials for deep space cruisers. This may not occur in any of our lifetimes, but it's going to happen someday.
Here's a link to vasimr stuff on Orbit Hanger Mods.

http://www.orbithangar.com/search_quick.php?text=vasimr&submit.x=0&submit.y=0

 

[Ark]

NASA needs to be dumping a ton of money into this, because trying to get to Mars with chemical rockets is just stupid. We've got concepts and prototypes for viable next-gen propulsion systems, and we need to be using them.

 

[Andy44]

trying to get to Mars with chemical rockets is just stupid.

Bingo!

Unfortunately, NASA will be lucky just to get enough money to build a rocket that can launch this stuff.

 

[Marcel]

Unfortunately, NASA will be lucky just to get enough money to build a rocket that can launch this stuff.

Well, NASA is going to install it on the ISS as a proof of concept. If we can't use the Ares 5 for some reason, the interplanetary spacecraft could be launched on the Proton, or perhaps the Chinese would be able to do it. I can see it now, Chinese space cruisers zipping around the solar system and NASA thinking, "WTF happened? Maybe we should research this stuff!"

edit: Just had a thought, If VASIMR works, we could send robotic vessels to grab the Voyager probes and bring them back to the Air and Space Museum!

Well, it's a nice thought, anyway.

The concept of chemical rockets to Mars vs VASIMR reminds me of the sci-fi meme where a colony ship travels to another solar system in some form of stasis. The colonists awaken at their destination around 100 years later to find the planet already inhabited by humans. The faster than light drive was invented shortly after they left.

 

[tblaxland]

An update:
VASIMR VX-200 Reaches 200 kW Power Milestone
http://www.onorbit.com/node/1577

Ad Astra Rocket Company's VASIMR(R) VX-200 rocket prototype reached its highly- coveted 200 kW maximum power milestone at 11:59 am (CST) in tests conducted at the company's Houston laboratory. The DC power trace actually exceeded the design requirement by 1 kW and exhibited the clear signature of a well established plateau at peak power.