Title: How to Make Plutonium
Headings: How to Make Plutonium
How to Make Plutonium
1 RECEIVE NEPTUNIUM-237
2 ELIMINATE PROTACTINIUM
3 CREATE TARGETS
4 IRRADIATE NEPTUNIUM
5 EXTRACT TARGETS
6 SEPARATE PLUTONIUM
7 SEND TO LOS ALAMOS

Content: It's got your calcium, platinum, and titanium. Your ytterbium, your strontium-90, and of course uranium-235 and plutonium-239 (responsible for Hiroshima and Nagasaki). In this catalog, plutonium-238 is the only-on-one-model-year carburetor from the old car you've somehow kept running: useful, unique—and discontinued. And the old car is a spacecraft: NASA missions bound beyond the influence of the sun, where solar power isn't an option, use radioisotope power systems (RPS) to create electricity from the heat of atomic decay. RPS that use 4.8 kilograms of fuel have powered experiments on the moon and Mars and launched golden records etched with the essence of human civilization to the edge of the solar system. They run only on plutonium-238, which is (relatively) cheap, has a suitable half-life, and gets plenty hot. But it was a by-product of Cold War–era nuclear weapon factories—now decommissioned—and by the 2010s there were fewer than ten RPS' worth remaining for NASA to use. So scientists lobbied the DOE to start making it again.