But it’s also hideously expensive. Plutonium is, apparently, one of the safer ways to build these things, because it is easy to shield, and the power density is good. But plutonium, as it’s not naturally occurring, is stratospherically expensive.
Additionally, the decay product of Pu-238 is U-234. Though a relatively 'safe' alpha emitter, it's half-life is ~200,000 years.
Note: With alpha emitters, it's 'safe' if it's outside your body, your skin can absorb it. But once you eat or inhale it, you get the full blast right into the quickest dividing cells in your body.
The first nuclear bombs cost billions of dollars each.
I wish I could say that’s a good thing. But no, after the first of them, nuclear weapons seem to have justified their own existence, no matter the cost.
I would rather see remaining weapons material repurposed as deep-space power sources. If that were to solve problems.
But it’s also hideously expensive. Plutonium is, apparently, one of the safer ways to build these things, because it is easy to shield, and the power density is good. But plutonium, as it’s not naturally occurring, is stratospherically expensive.
https://en.wikipedia.org/wiki/Radioisotope_thermoelectric_ge...