Scientists have calculated what it would take to sterilize the planet. No wait, stay with me! It's not as morbid as it sounds!
Three scientists from Oxford and Harvard universities were interested in just what it would take to sterilize the Earth — not just wipe out humanity, but get a really deep scrub in there and completely wipe out life.
What they found is that life could survive pretty much anything the universe is going to throw at us for at least 7.6 billion years.
To figure this out, they looked at the greatest survivors ever.
Not humans. Not sharks. Tardigrades.
Big, impressive life — humans and whales and Tyrannosaurus rexes — are actually kind of fragile. We depend on very specific environments to survive. But there are much tougher creatures out there, wriggling around, like tardigrades.
[rebelmouse-image 19529581 dam="1" original_size="420x237" caption="Tardigrades are basically tiny little Terminators. GIF from "Cosmos."" expand=1]Tardigrades are basically tiny little Terminators. GIF from "Cosmos."
Also known as water bears, these microscopic little guys are tough as nails. Tardigrades can be frozen, irradiated, starved for decades — heck, they've even survived the vacuum of space!
After doing a bunch of math about radiation and pressure and other factors, the scientists determined the only way to wipe out these little buggers would be to boil the entire ocean. Let me repeat that: The only way to get rid of them is to boil the ocean.
And boiling the ocean just isn't likely to happen anytime soon. You'd have to slam the planet with a truly gigantic asteroid, or hit it with a supernova or an ultra-powerful gamma ray burst. The scientists did the math, and they say all of those are just too rare or too far away to matter to a tardigrade.
"Life, once it gets going, is hard to wipe out," study co-author Dr. David Sloan said in a press release.
[rebelmouse-image 19529582 dam="1" original_size="430x257" caption="GIF from "Jurassic Park."" expand=1]GIF from "Jurassic Park."
Basically, life on Earth is probably going to survive as long as the sun does.
Unfortunately, there is an end point. In about 7.6 billion years, the sun's going to evolve into a red giant star. At that point, it'll either devour the Earth or be bright enough to, yes, boil the oceans.
That's a long way away. Life has only been on Earth for about 3.8 billion years — multicellular life even less. In only about 600 million years, we went from worms to dinosaurs to Carl Sagan. Imagine what another 7.6 billion years will get us. Life on Earth hasn't even hit middle age yet.
The researchers say this gives hope to the possibility of finding life on other planets.
Perhaps the deep soils of Mars or the volcanic oceans of Europa or Enceladus have their own little microscopic Terminators too.
"If tardigrades are Earth's most resilient species, who knows what else is out there," said Dr. Rafael Alves Batista, a co-author of the study.
That doesn't mean we humans should take our sturdy little home for granted, though.
Remember that tardigrades are little Terminators. We're not. Humans, it turns out, really like Earth the way it is now.
If we want to last as long as the tardigrades do, we have some work ahead of us — like preparing for climate change, protecting the biosphere, and maybe keeping an eye out for some of those smaller asteroids.
But if these scientists are correct, no matter what, life on Earth is going to survive a long, long time.
So take that, universe, you're stuck with us.