NASA Wants Revolutionary Radiation Shielding Tech

coondoggie writes "Long term exposure to radiation is one of the biggest challenges in long-duration human spaceflights, and NASA is now looking for what it calls 'revolutionary' technology that would help protect astronauts from harmful exposure. 'It is believed that the best strategy for radiation protection and shielding for long duration human missions is to use electrostatic active radiation shielding while, in concert, taking the full advantage of the state-of-the-art evolutionary passive (material) shielding technologies for the much reduced and weaken radiation that may escape and hit the spacecraft.'"

Comments

Huh?

[StefanJ]

With the exception of Project Orion, all of the nuclear propulsion concepts I've read about, and even the actual trials made in the 1960s, have much lower thrust than chemical fueled rockets. In the case of ion and plasma thrusters, vanishingly little thrust. Even in the case of fission/thermal rockets (e.g., NERVA), only about a third of the thrust of chemical rockets. They are less suitable for getting stuff into orbit than chemical rockets.

Once you're in orbit (or beyond), thrust counts for much less than exhaust velocity.

And as for Project Orion: Yeah, some of the proposed designs could heave a pretty damn big ship into orbit, But the fear of fallout from hundreds of little atomic bombs going off in the atmosphere is anything but irrational. One of the principles of the project, Freeman Dyson, specifically stated that the risk wasn't worth it. (I mean, maybe if there was a big asteroid on the way . . .)

And . . . jeeze:
"Water, when exposed to vacuum, freezes."

No, it evaporates.