Stories, updates, insights, and original analysis from The Planetary Society.

The ASRG Cancellation in Context

ASRGs could have stretched NASA's limited supply of plutonium to potentially enable missions to the perpetually-shadowed polar craters on our moon, to flyby Uranus, or to float for months on a Titan lake.

NASA Just Cancelled its Advanced Spacecraft Power Program

The Advanced Stirling Radioisotope Program (ASRG) was just cancelled by NASA. This was to be the saving grace for Plutonium-238 availability, as it was a much more efficient way to generate electricity than classic RTG systems.

Power From the Isotopes

We report on the current state of Plutonium-238 production in the United States, a crucial fuel source for planetary exploration spacecraft.