NASA is running out of the special kind of plutonium needed to power deep space probes, worrying planetary scientists who say the U. S. urgently needs to restart production of plutonium-238.
But it’s unclear whether Congress will provide the $30 million that the administration requested earlier this year for the Department of Energy to get a new program going.
Nuclear weapons use plutonium-239, but NASA depends on something quite different: plutonium-238. A marshmallow-sized pellet of plutonium-238, encased in metal, gives off a lot of heat. more>>>