How NASA Prevents a Space Plague Outbreak

In the early days of space exploration, NASA basically made up procedure on the fly. With little knowledge of the world outside our atmosphere, agency physicians worried what humans might encounter out there. Maybe John Glenn would go Space Blind. Maybe the Apollo 11 crew would track an Andromeda Strain through the Lunar Command Module, unleashing a deadly moon virus on a defenseless earth.

Better safe than sorry, NASA figured. Here's how scientists attempted to protect our planet—and the rest of the solar system—from the threat of extraterrestrial microbes.