The animal that survived the vacuum of space

Tardigrades, also called water bears, live in moss, on the seabed and in almost any drop of water on the planet. When their surroundings dry out, they push out nearly all their internal water, curl into a little ball called a tun and shut their metabolism down almost completely.

In that state they endure the unthinkable: temperatures near absolute zero, crushing pressures and doses of radiation that would wipe out any other animal. In 2007, the European FOTON-M3 mission placed tardigrades outside the spacecraft and left them exposed to open space. Many survived the vacuum, and a few even withstood direct solar radiation; several laid healthy eggs once back home.

It's not that they're indestructible: in everyday life they're fragile. But they know how to switch off, wait and switch back on. Life, it turns out, can fit on pause inside a speck of dust.