They grow to 1mm long. But don't let their size fool you.
They like to live near water.
These tiny creatures once hitched a ride on the outside of a space shuttle.
They barely even noticed.
On Earth, they've been found at the top of a mountain in the Himalayas.
And under 80m of ice in a glacier in the Arctic.
And in Japanese hot springs.
A trip to the bottom of the Marianas trench would be no big deal for a tardigrade. They can survive under SIX TIMES as much pressure.
They cope with less-than-ideal conditions by shutting down their bodies until they're almost dead.
And have been known to hang around like that for 120 YEARS.
Too much radiation can damage their DNA. But that's ok, they'll just repair it.
It's basically impossible to kill a tardigrade.
So let's just hope they don't get any ideas.