They live in the highest peaks of the Himalayan mountains. You can find them in the deepest trenches of our oceans. You can even scoop them up when you pick up moss in less exotic locations like Central Park.

They are everywhere—thriving in the most harshest conditions, from the frigid cold to boiling hot temperatures. They can live through intense radiation. They have even survived the most deadliest place of all: the vacuum of space.

In recent years, the Internet has become obsessed with Tardigrades (otherwise known as water bears). And, really, that’s a good thing considering microscopic creatures don’t exactly make for a sexy story.

But there’s something about these resilient critters that continue to captivate biologists and non-biologists alike, even though they don’t do much with their lives other than eating plants and bacteria (and sometimes, they’ll even eat other tardigrades, too!)

Heres the thing: Tardigrades are strange. Really strange. Maybe that’s why they have taken over the Internet—because they’re fantastically weird. I also have to admit: Water bears are also incredibly cute!

Or maybe we love them because they’re the closest we’ll ever get to seeing immortality in the flesh. Something that’s coveted by humans who—let’s face it—are really quite fragile.

So the big question on everyone’s mind is: How can these little guys survive such harsh environments?

Whenever they find themselves in sticky situations–like a dry lake or the vacuum of space—tardigrades can enter a sort of suspended animation where they dry up and turn into a lifeless ball. It’s like death in a way.

What’s more amazing? They can survive in this state for years or even decades without food or water. They are revived again whenever they reenter water or are reintroduced to their naturally mossy environments.

The big question, though, is how they can survive “drying out” in the first place? Being completely devoid of moisture, is, well, deadly for most animals.

During the process of drying out, tardigrades “produce a special type of ‘bioglass’ to hold essential proteins and molecules together until they’re rehydrated back to life,” according to a recent University of North Carolina study shared by user unique_leek_critique in Reddit’s science community. When tardigrades are exposed to water, the glass melts.

In fact, the researchers discovered specific genes that code for proteins that are responsible for the production of tardigrade glass.

“When you remove the water, they very quickly coat themselves in large amounts of glassy molecules. That’s how they stay in this state of suspended animation,” said University of Chicago researcher and molecular engineer, Juan de Pablo.

We are only just beginning to understand the weird world of tardigrades, but researching their survival methods can perhaps lead us to invaluable discoveries in the future.