NASA Returning To Nuclear Programs

Popular Mechanics ^ | FR Post 6-16-02 | BY STEFANO COLEDAN

[vannrox]

The Kuiper Express spacecraft may be sent to Pluto.

NASA Returning To Nuclear Programs

BY STEFANO COLEDAN

NASA may go nuclear again to provide power for both instruments and propulsion to spacecraft flying on deep-space missions. With Sean O'Keefe as its new chief, and the blessing of the Bush administration, the space agency plans to bring nuclear fission reactors back in style.

Besides getting all the electricity they need from radioisotope thermoelectric generators (RTGs), spacecraft propelled by nuclear engines will cut considerably the travel time to distant planets, says Ed Weiler, NASA's chief scientist. "For 40 years NASA has been doing planetary science in the same way. That is, you accelerate for 5, 10, 15 minutes, and then you stop. And you coast, and you coast, and you coast," Weiler says. "That's not the way to do exploration."

The first to take advantage of NASA's new nuclear trend could be Kuiper Express, a spacecraft designed to take the first closeup look at our solar system's outermost planet--Pluto. Even though the mission was recently killed, it could come back to life as a candidate for nuclear propulsion. The last time NASA launched a nuclear-powered spacecraft was in 1997, when it sent Cassini and 72 pounds of plutonium toward Saturn. Since then, the space agency has let its RTG inventory dwindle down to one.

Unlike chemical rockets, which burn for only a few minutes, nuclear engines can burn for months. That means spacecraft can go much faster, conceivably turning a round trip to, say, Mars from a 3-year affair into a cruise that would last only about 12 weeks.

Other Nuclear Rocket Plans

• NASA's Antimatter Spaceships

• Nuclear Space Cruiser

[vannrox]

Exciting.

[Rebelbase]

I just hope they remember to lube the O rings prior to launch.

[Straight Vermonter]

I have hoped to hear this for quite a while now. After reading about the early successes in the nuclear space program I realize we might have been shooting for the outer planets by now rather than just our nearest neighbor.

[Imal]

Exciting indeed! Certainly, when dealing with such deadly substances as plutonium, extra precautions must be taken. But the rewards of allowing for more potent power sources on spacecraft outweigh the risks.

Imal

[jennyp]

I forget. How would a nuclear rocket engine work? Does it heat up something & shoot it out the back? Why would this be more efficient than a controlled chemical explosion (i.e. conventional method)? And how much of this expelled matter would it have to keep onboard for a Mars trip?