Originally posted by: Mday
it's being tested. their next thing is ion propulsion. and it would still take forever to get to mars.
Yeah, the force they exert was described as being similar to that exerted on your hand by a piece of paper resting on it. Not a good way of speeding up a craft, but it will provide that little bit of force for a long time.
There needs to be some system, assuming it's even possible, to reduce the inertial forces acting on the passengers of a ship, before we can really get anything fast. I unfortunately can't remember enough of my physics math to figure out how long it'd take to accelerate to the speed of light, and keep the forces under 1G...I'll try though.
Assume 10m/sec squared acceleration. Light travels at around about 300,000,000m/sec. I don't think it's as simple as 300,000,000/10; isn't it a trinomial equation here? I just can't remember it anymore.
It'd take a really long time though just to get to that speed. Then there'd be the wait while the ship would decelerate without killing everyone onboard. Even going to the Enterprise's 1/4 impulse speed would take awhile.
Originally posted by: Fencer128
We already do on a regular basis. Not for propulsion but for onboard power.
I was under the impression that very nearly all satellites use solar power for onboard systems. Could you link me to some of these nuclear reactors that go up on a regular basis?
Cheers,
Andy
Satellites that orbit Mars or planets closer to the Sun use solar power; I think that Galileo around Jupiter is nuclear powered - beyond Mars, the sunlight is just too weak to power a satellite, using current solar cell technology anyway, so they use nuclear generators. Not many interplanetary probes are launched though.
Originally posted by: sgtroyer
It's been done. Cassini (which went to Saturn, I believe) had a small nuclear reactor, and it was very controversial. Lots of risk assessment to figure out whether it could come back down and contaminate something. Lots of people were pretty worked up about it.
I don' t think the benefit was lots of thrust, but rather a very small light source of long lasting power.
Ah yes, that controversey. I think that NASA said that the way the (small amount of) radioactive material was contained, it could have survived re-entry without killing everything on the planet, and even better, without spreading any dangerous radiation into the environment. All these people worked up over this...we face a greater threat of nuclear disaster from sources already on the planet, contained in warheads that are
designed to cause destruction.
Originally posted by: Smilin
Sorry Andy, no immediate link for you on this. I became aware of it because of some big protests over the launch of this one with a particularly large reactor. I didn't even know we did such a thing but when I was reading the news concerning this one launch I found out that it was far from the first launch of a reactor into space.
I think the Pioneer spacecraft that went out past Jupiter were nuclear powered; both Voyager craft were also nuclear powered.