Space agencies already have a shortlist, and the top contenders are wildly unexpected.
If you think the first animal to survive on another planet is going to be some photogenic lab dog in a tiny space helmet, think again. The real contenders are a mix of tiny, bizarre, and almost unfairly tough. We’re talking creatures that can shrug off radiation, play dead for decades, and come back to life after being frozen solid. The more you learn about them, the more you’ll realize… humans might be the weak link.
1. A microscopic survivor already passed a space test.
Tardigrades are basically the Marvel superheroes of the microscopic world. NASA literally launched them into open space in 2007, and they survived the vacuum, radiation, and freezing cold like it was just a weird weekend away. Then they got rehydrated and carried on with life as if they hadn’t just been in the void.
When they’re in “cryptobiosis,” their bodies shut down almost completely, letting them survive being boiled, frozen, or blasted with cosmic rays. They’re already proven they can handle space without a fancy life-support system. Honestly, if anyone’s going to colonize Mars first, it’s going to be these indestructible fuzz-specks.
2. The insect with a built-in astronaut suit.
Cockroaches may be gross to you, but to scientists, they’re like self-sustaining space janitors. As stated by entomologists who study radiation resistance, German cockroaches can handle high-radiation environments, live on next to nothing, and thrive in sealed habitats.
They’re basically the perfect maintenance crew for a closed-loop space station—turning scraps into something useful, cleaning up the ecosystem, and not caring if the atmosphere shifts a little. Sure, they won’t win a cuteness contest, but in space, usefulness is the only beauty standard that matters.
3. A fish that can breathe without water for days.
The climbing perch is a fish that plays by its own rules. It has lung-like organs that let it breathe air for nearly a week, and it can walk—yes, walk—across land to find new water. Australian marine biologists have seen it do this without missing a beat.
That means in a Mars aquaponics setup, it could still survive if a pump failed or the water system wasn’t perfect. You wouldn’t need to baby it like delicate aquarium fish—it’s more of a “figure it out and keep going” kind of roommate.
4. An Antarctic bug that treats freezing as a nap.
There’s a midge in Antarctica that literally freezes solid every winter and thaws out in the spring like nothing happened. It loses most of the water in its body and still functions, thanks to its built-in antifreeze proteins.
On another planet, that trick could be priceless. You could put it in stasis for transport, then thaw it out to start life in a controlled habitat. If it laughs in the face of Antarctic winters, it’s not going to be bothered by a chilly Martian night.
5. A worm that ignores high radiation levels.
Some nematodes are like the honey badgers of the microscopic world—they just don’t care. They can withstand insane levels of radiation thanks to their ridiculously efficient DNA repair systems.
On another planet, they’d be the underground crew—literally. Working in the soil, breaking down waste, and creating fertile ground without keeling over from cosmic rays. They’re not glamorous, but they’d be doing the grunt work no one else wants to do.
6. A shrimp that can survive in a vacuum.
Brine shrimp—aka your childhood “sea monkeys”—have eggs that can survive being dried out for years, then spring back to life when dropped in water. Some of those eggs have even been exposed to space vacuum and still hatched.
This means you could ship them to another planet in a bag, store them for ages, then start a mini aquatic food chain whenever you’re ready. They’re like little protein packets you can keep in a drawer until it’s go time.
7. A beetle that thrives on almost nothing.
Darkling beetles basically live in extreme desert conditions on scraps, so a sealed Mars habitat is going to feel like a five-star resort to them. They’re moisture-hoarding champions with a knack for breaking down waste into something useful.
Plus, they won’t be picky about what’s for dinner, which makes them an easy fit for a closed ecosystem. They’re not flashy, but they’re the kind of low-maintenance, always-working tenant you want in your cosmic apartment building.
8. A snail that hibernates for years without harm.
Some desert snails can seal themselves in their shells for literal years, waiting for conditions to improve. No food, no water, no problem—they just hit pause on life.
That makes them incredibly easy to transport between planets. You could send them into space, wake them up on arrival, and they’d be ready to do their thing like no time had passed. They’re basically the masters of long-haul travel without the jet lag.
9. A frog that turns itself into a popsicle.
The wood frog freezes solid every winter, heart stopped and all, then thaws out in spring ready to hop off. It uses glucose in its blood as antifreeze to protect its organs from damage.
In space, that same strategy could be a goldmine for figuring out how to put bigger animals—or people—into stasis for long trips. For now, the frog’s just out here being a walking science experiment.
10. A tiny crustacean that eats waste and cleans water.
Amphipods are little, shrimp-like scavengers that munch on decaying material while naturally filtering water. They don’t need perfect conditions, and they can adapt to different water chemistries like champs.
Stick them in an off-world aquatic system and they’d quietly keep it running—recycling waste, cleaning the water, and providing a bonus protein source. They’re the silent workhorses you’d never notice… until something breaks and you realize they’ve been holding the whole system together.