Wow, such negativity. > There's no spacecraft-related reason to select this—it's strictly worse—it's just the US/EU are in a decades-long ongoing shortage of P

Wow, such negativity. > There's no spacecraft-related reason to select this—it's strictly worse—it's just the US/EU are in a decades-long ongoing shortage of Pu-238, and this is the only available alternative. I don't think this is "pioneering" in any positive sense of the word. IMHO, it's embarrassing. No, but there are practical reasons to select this. It doesn't matter _why_ Pu-238 is unavailable, it matters that it is unavailable and this has been a heavy constraint on space missions. New Horizons almost got postponed (with a danger of cancellation) due to this. And even then it launched with 80% fuel. The question is, can they deliver americium RTGs ? That would be great.