By the time the alarms go off, he’s back on his feet, hoping the rover wasn’t filming, but knowing that it was—that his face-first sprawl on the surface of Phobos has been recorded for posterity. The visor’s fiber-optic display flashes ominously: suit breach. His body, or some small sliver of it, has been exposed to the raw, airless vacuum of a Martian moon.
An astronaut can die many ways, but decompression is one of the more gruesome. A punctured space suit means a race to sanctuary, before the envelope of pure oxygen surrounding the body bleeds away and hypoxia causes the person to black out. Rapid pressure loss isn’t explosive, but it’s ugly: Water in the body begins to vaporize and tries to escape, the lungs collapse, and circulation shuts down.
No one’s dying today, though, at least not on Phobos. The suit he’s wearing isn’t a pressurized balloon. It’s the reverse, really—a squeeze suit, with a lattice of smart-memory alloys that binds it to the body, replacing an oxygen cus...