Doesn't talk about the downsides, which are mainly that Am-241 has about five times lower power density than Pu-238, and also needs additional radiation shielding.
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.
https://en.wikipedia.org/wiki/Radioisotope_thermoelectric_ge...
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.