NASA's Top 5 Technical Challenges Countdown: #2: More Power
What we have now just…isn't going to cut it. Right now if you want power in space you essentially have two options: solar panels, and a kind of nuclear power called radioisotope thermoelectric generators.

What we have now just…isn't going to cut it. Right now if you want power in space you essentially have two options: solar panels, and a kind of nuclear power called radioisotope thermoelectric generators.