Everybody's favorite adorably-monikered, microscopic
invertebrate continues to prove that it's also one tough little
"bear". Water bears*—long recognized as hardiest animals on
Earth—can also, apparently, survive in the vacuum of space,
according to a European Space Agency experiment published in the
journal Current Biology. But, before offering the inevitable
welcome speeches to our water bear overlords, it's worth noting
a couple caveats. First, these water bears weren't just hanging
out in open space, wriggling around. Instead, they were in a
dehydrated state—a sort-of mega-hibernation that allows water
bears to go without water, and appear dead, for years, before
being revived. In the video above, you can see a water bear
drying out into a little nub, called a tun. But he revives after
water floods the petri dish. It was tuns that went to space, not
active water bears. Second, the creatures didn't hold up nearly
as well against the Sun, as they did against Space, itself. New
Scientist explains: Ultraviole