We might find alien life in 2027 days. That's not science fiction — it's NASA's latest bet on one of Jupiter's moons.
For decades, scientists have suspected Europa might harbor life. Forty-two years after Arthur C. Clarke first suggested it in his novel "2010 Odyssey 2," NASA is actually launching the most advanced mission ever designed to hunt for signs of alien life. The spacecraft is called the Europa Clipper, and it's heading toward Jupiter's moon Europa.
But there's a problem: Jupiter kills almost everything that gets close to it.
The gas giant generates a magnetic field nearly 20,000 times stronger than Earth's. If you could see this magnetic field from Earth, it would appear twice as big as the full moon. Right in the middle of Jupiter's system lies Io — the most volcanically active world in our solar system. Io shoots out tons of sulfur dioxide every second. These particles get trapped inside Jupiter's magnetic field and accelerate to over 300 kilometers per second, whipping around the planet and slamming into other moons.
This creates massive radiation belts that span past Europa and all the other Galilean moons. For electronics, this intense radiation is like kryptonite. Even with modern shielding, a spacecraft within these radiation belts would only survive about three months.
So how will NASA's mission survive for over four years without getting fried?
The solution is elegant: it won't orbit Jupiter continuously. Instead, the Europa Clipper will orbit Jupiter from afar and then swoop in every few weeks to quickly fly by Europa before escaping again. The spacecraft will do 49 flybys, mapping almost the entire surface. That's how it got its name — inspired by the fast and nimble 19th-century clipper ships that dipped in and out of ports.
Why Europa?
Of all the places in the solar system to look for life, why Europa? If you stood on its surface, you'd be hit with 5,400 millis of radiation in a single day — that's 1,800 times more than the annual dose here on Earth. You'd die from radiation sickness after a couple hours.
But Europa holds a secret. When Voyager 1 passed by Jupiter in 1979, it took this photo of Europa. Compare it to most other moons in the solar system and you'll notice something missing: craters. Every planet and moon has been bombarded by asteroids over billions of years, and most planetary surfaces show that history. But not Europa.
Something recent — say, over the past 60 million years — must have been happening on Europa to erase most of these craters from the surface.
Sixteen years after Voyager, Galileo arrived at Jupiter and spent eight years studying both the gas giant and its moons. The mission picked up something interesting: Jupiter's magnetic poles aren't aligned with its geographic poles. As the planet rotates every 10 hours, the whole magnetic field wobbles. This changing field induces a relatively strong magnetic field on Europa, and readings from Galileo indicate it must be somewhere close to the surface — only tens of kilometers deep.
What kind of conductive layer? Europa's white surface is almost entirely covered in a thick crust of water ice. These reddish-brown regions, when observed through a spectrometer, fit the description of hydrated salts, sulfuric acid, or even bacteria. Scientists need more data to be sure.
But recent experiments at JPL found that sea salt, when bombarded with intense radiation, turns from white to this same brownish color found on Europa. So scientists suspect there's a whole saltwater ocean inside Europa that could be 100 kilometers deep — meaning Europa would contain twice as much water as all of Earth.
How Can Liquid Water Exist Here?
The Jupiter system only gets about 4% of the sunlight we get here on Earth. You'd expect the entire ocean to be frozen solid since Europa's surface is constantly below 160 degrees Celsius.
But there's a way to generate heat that doesn't rely on the sun. Europa's orbit around Jupiter isn't a perfect circle. It's because Io, Europa, and Ganymede are all in orbital resonance: each time Ganymede completes one orbit, Europa completes two, and IO completes four. Because of that, IO tugs Europa inward on one side of the orbit while Ganymede pulls it out on the other, making its orbit more eccentric.
Jupiter's pull is stronger on the closer side of the orbit than on the farther side. So Europa is constantly being stretched and squeezed — like this rubber ball getting warmer as it's squeezed. Scientists believe the friction caused by the tidal flexing of the entire moon can generate enough heat to keep the ocean liquid.
If there's no ocean, Europa should flex by only about one meter in amplitude. But if there's an ocean in there, then it flexes with an amplitude of 30 meters — that's an enormous deflection that will show up clearly in gravity data.
The Case for Life
How long has Europa had this ocean? It could be 4 billion years. We don't know for sure, but that amount of time could give life the opportunity to evolve in those oceans.
We're not talking about searching for fishes or whales or squids — we're looking for single-cell organisms. Organisms can use methane, carbon dioxide, sulfur reactions. Any chemical reaction you can think of that might happen in the ocean can potentially be used as a fuel for that organism's metabolism.
On Earth, we find hydrothermal vents thousands of meters below the surface with no sunlight. These vents are oases for ocean life. The life forms down here rely on unique bacteria that feed on the minerals from the vents rather than from the energy provided by the sun.
The radiation bombardment actually makes Europa a better candidate. Those high-speed particles hitting Europa's surface give water and carbon dioxide molecules enough energy to form new compounds like perchlorates or hydrogen peroxide, and these can serve as food for life beneath the surface — if they can get down that deep.
We have evidence of overturn of the icy shell at chaos zones where the icy crust seems to have collided and material has been shoved into the icy shell. There may be ways for this fuel for life to get down into the ocean.
The Mission Itself
The Europa Clipper won't need to touch down on the surface to confirm this. There's a red spectrometer to look at the chemical fingerprints of light bounced off the surface to help identify and map out where the salts are, find if there are organics. There's a ultraviolet spectrograph aboard the spacecraft to look for plumes — are they there?
And then there's imaging of essentially the whole globe at better than 100 meters per pixel resolution. One camera will take swaths of images as we fly over the surface — that's called the wide-angle camera. And then the other camera is the narrow-angle camera from 50 kilometers altitude; it will get half-meter-per-pixel images. It'd be able to resolve this desk if it were on Europa.
A future mission like a lander would actually search for signs of life at Europa. Studies suggest we can get a lander living on the surface for months — that's sufficient to go in there, scoop some stuff up from below the depth of radiation processing, and put it into a mass spectrometer to see what we see.
The European Space Agency's JUICE mission — or Jupiter Icy Moons Explorer — is already on its way. It will arrive at the system just 15 months after Clipper and do a few flybys of Europa before settling into a tight orbit around Ganymede. Having two spacecraft there at the same time would mean we could coordinate observations: we'd see a big burst coming from Jupiter in our magnetic signals, and JUICE might say they felt that over there in their magnetic signals. We wouldn't have to do anything different except talk to each other and make sure the sum is even bigger than its parts.
When Will We Know?
The Europa Clipper was scheduled to launch on October 10th, 2024, but NASA is waiting for Hurricane Milton to clear Florida before the spacecraft can take off safely. When will we get the first results? You'll start seeing distant observations coming in in 2030 as we look at Europa from afar and search for plumes. Then you'll see the first really high-resolution data in 2031.
After 26 years of thinking about a mission to Europa, how does it feel to be so close to launch? It's a little surreal — it's occasionally hitting me that our spacecraft is going to be up there in the heavens, right on its way.
Critics might note that Europa's intense radiation makes it a hostile environment for life as we know it. Some scientists argue Enceladus seems like a stronger candidate since we've already captured images of plumes shooting out of Saturn's moon and even flown through them — we're almost 100% certain there's a subsurface ocean there. But Europa has been evolving for much longer, and the radiation actually provides chemical energy that could feed life.
"We might find alien life in 2027 days."
Bottom Line
The strongest part of this argument is clear: we have real evidence of a vast subsurface ocean on Europa, with tidal heating providing constant warmth, and chemical energy from radiation feeding potential life. The mission is actually launching soon. But the biggest vulnerability is that we still don't know if life actually exists there — the Clipper can only confirm whether conditions are right. Finding actual organisms would require a future lander mission, and even then we'd need to hope those single-celled life forms left enough trace evidence for us to detect. The clock is ticking: in about 2,027 days, we might finally know if we're not alone.