On: Ion engines could take us to the solar gravitation...

[perihelions]

All space nuclear fission reactors use weapons-grade uranium—they'd be impractical otherwise.

[littlestymaar → perihelions]

Is there anything like a "space nuclear fission reactor" in the first place? My understanding was that all the so called "nuclear reactors" in space where jus powered by radioactive decay of short-lived material, not by fission.

[two_handfuls → littlestymaar]

Oh yes there is. The soviets launched two 6 kilowatt fission nuclear reactors in space.

https://en.m.wikipedia.org/wiki/US-A

[littlestymaar → two_handfuls]

Ah, I wasn't aware of that, thanks!

[philipkglass → littlestymaar]

Also one American reactor: https://en.wikipedia.org/wiki/SNAP-10A

[Iwan-Zotow → littlestymaar]

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