9.73% Chance That US Spy Satellite Will Crash on or Near a Human Being

Duck and cover boys and girls. A broken-down photo-recon satellite the size of a shortbus has had it with piping close-ups of the blinding bald patches of C.I.A. operatives into their own Blackberries as they distribute Kalashnikovs and crack to third-world babies. [Phew.]

The disillusioned satellite is reported to have given its entire record collection to an obsolete cellphone satellite and seems to be inching ever closer to the precipice of uncontrolled reentry.

At 20,000 pounds, the U.S. spy satellite is about an eighth of the size of the abandoned space station Skylab, which in 1979 broke apart and crashed into the Indian Ocean (as well as maybe speed-cooking a few wallabies in the far Australian outback).

Generally speaking, when the U.S. Government wants to dispose of a spy satellite, they gently guide its poisonous bulk into one of those reservoirs of biodiversity, our planet's oceans. This strategy is meant to eliminate the possibility of the 'enemy' reverse-engineering the satellite or retrieving any information from the air-fried remains.

But never mind the litter—the squid and angler fish could use a little space-themed jungle gym down there! And some hydrazine. Yes, the chief poison aboard our errant robo-spy is the rocket-fuel element hydrazine. Hydrazine has been described as "highly toxic and dangerously unstable." So, aside from activating the "Act of God" clause in someone's home or habitat, the satellite is going to rain various forms of biomedical plague on whatever it lands near.

Since oceans cover approximately 70.8% of the earth's surface, there is of course, a 70.8% chance that it will land in one. Hydrazine is a recognized carcinogen and can be found residually in the bodies of some fishes living in contaminated water. Generally speaking though, in the water the substance degrades into "less toxic" substances in a matter of weeks, and is not found at high levels over long periods of time.

3 quarters of the earth's population lives on 20% of its non-ocean land surface. More precisely, in the book Human Population Dynamics, John Clarke writes, "The earth's inhabited area . . . occupies less than a third of the earth's surface and despite massive world population growth, is remarkably stable."

So—someone hit the tympani and roll a menacing organ chord please—this means that by a conservative estimate there is a 9.73% chance that the satellite will land in an inhabited area.
If it doesn't instantaneously frappé or flash-fry you, here is the outlook for acute exposure to hydrazine (woot!): "nausea, vomiting, uncontrolled shaking, inflammation of the nerves, drowsiness, or coma," as well as, "coughing and irritation of the throat and lungs, convulsions, tremors, or seizures." Not to mention, "dyspnea and pulmonary edema." And lets not forget that dogs, rats, and mice have been shown to die shortly after acute exposure. Oh, yeah. Cancer.

But don't worry, when vaporized in air hydrazine degrades in minutes or hours. Bonded to soil this takes a few hours. Not recommended as a condiment though.

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