Military-Grade Awesome

Oh SNAP-10A! Nuclear Space Odyssey FTW

Let me begin by saying that the Wild West era of space exploration is an endless source of tech-geek pron, as you, dear readers, already know. engineerd’s™ Buran post yesterday tickled that part of my brainstem that demands to surf Wikipedia articles concerning space tech for several hours, and I am helpless to do anything but obey. And look what I found – the SNAP-10A (Systems for Nuclear Auxiliary Power), an orbital nuclear reactor! And it ain’t no radioisotope decay thermoelectric unit, neither – this is the real fission-filled deal.

This radioactive ice cream cone is still orbiting the Earth (bone-chilling foreshadowing: although not in one piece. We’ll get to that later), so let’s figure out what’s up there. First, you have the tiny reactor – 9″ wide by 15″ long – which is the toaster-sized object at the top of the cone (I couldn’t resist). Inside were 37 uranium-zirconium-hydride fuel rods, controlled by a series of beryllium-coated reflectors that reflected radiated neutrons back into the rods to continue and control the reaction. If the reactors were disabled, the reaction would fizzle out. This was a controllable option – explosive bolts could hurl the reflectors off into space, shutting the reactor down. I assume this involved pushing a fantastic-looking button under a glass case, guarded by robot sharks and a sexy double-agent femme fatale. EurythmicEutectic sodium-potassium alloy was circulated through the reactor core to cool off the system, as well as to convey thermal energy to the thermoelectric generator, producing about 30kW (about 40 HP to our engine-oriented friends) due to the Seebek effect, utilizing the rather intense temperature differential between the cold vastness of space and the hot sodium-potassium.

They bide their time. They have 4,000 years. Their day will come.

Hurtled skyward on an ATLAS Agena D rocket into low-earth orbit in 1965, the 10A worked flawlessly for 43 days. Unfortunately, it was designed to run for a year. Whoops! A voltage regulator crapped out, and the reactor shut down, stranding the 10A in a 700-mile-high orbit around Earth. This orbit should be stable for 4,000 years, at which point lemurs will have overthrown us and set up a highly advanced civilization based on the Macintosh OS – so we’re cool, right? Well, two problems. First is that uranium has a half-life of approximately a gazillion years, and the second is that in 1979 an “anomalous event” occurred that caused SNAP-10A to shed approximately 50 pieces. That’s the alarmist spin. The objectivist spin is that even supposing that a micro-meteor impacted our dear SNAP reactor and sent its death-rattle of uranium hurtling outward, 700 miles is a LONG way from the atmosphere, and the heat produced from the friction of reentry is going to do a pretty good job of destroying or widely dispersing a the radioactive material. So don’t start bowing down to your lemur overlords just yet. You’ll be good and properly dead before SNAP-10A gets its revenge by giving two lemurs a 15% greater chance of developing tail cancer. So there.