Tardigrades: The Microscopic Time Travelers

In 2007, eight species of tardigrade floated outside the FOTON-M3 spacecraft for more than ten days, unprotected in the vacuum of low Earth orbit. The temperature swung from 149 degrees below zero to more than 212 above, ultraviolet radiation bombarded every cell, and cosmic rays-100 times stronger than on Earth’s surface-smashed through their bodies. A single second of exposure to that radiation would shred most animal DNA, but more than 68% of the tardigrades returned not just alive, but able to lay eggs that hatched normally. Some even came back with their signature lumbering walk. And the secret wasn’t a shell or thick skin, but a protein called Dsup, first sequenced from Ramazzottius varieornatus in 2016, that wraps around their DNA and blocks radiation damage at the atomic level. This is how a microscopic animal less than half a millimeter long can travel through outer space-and wake up as if nothing happened.