OOPS: NASA’s Plutonium Problem Could End Deep-Space Exploration. “The country’s scientific stockpile has dwindled to around 36 pounds. To put that in perspective, the battery that powers NASA’s Curiosity rover, which is currently studying the surface of Mars, contains roughly 10 pounds of plutonium, and what’s left has already been spoken for and then some. The implications for space exploration are dire: No more plutonium-238 means not exploring perhaps 99 percent of the solar system. In effect, much of NASA’s $1.5 billion-a-year (and shrinking) planetary science program is running out of time. The nuclear crisis is so bad that affected researchers know it simply as ‘The Problem.'”