Life on another planet. It almost seems like a buzz-“phrase” at this point, with scientists keeping the search up for over 100 years. What started as astronomers examining the planets through telescopes and claiming that they saw “canals” on Mars has expanded into sending countless robots and probes to other worlds, but, as of now, we still haven’t found anything indicative of life existing, or ever having existed, on another planet. But what if we’re looking in the wrong place?
Enter: Jupiter. It’s not exactly the most obvious place to search for life. As our solar system’s largest planet and a gas giant, as far as we can tell it doesn’t exactly have conditions conducive to hosting life. But Jupiter has another thing: moons. While Saturn has slightly more, Jupiter clocks in with an impressive 95 confirmed moons, several of which, the Galilean moons (named as such because Galileo could see them with his telescope), are quite large. These moons are, in order of how close their orbits are to Jupiter, Io, Europa, Ganymede, and Callisto. But, for this article, we’re going to be focusing on Europa, one of the most fascinating objects contained within our solar system.
Europa at first glance is relatively unassuming. It looks pretty much like any other moon we’d imagine, rocky and gray, with several craters pock-marked across its surface. Upon closer inspection, however, you may see that there aren’t that many craters compared to some other objects with negligible atmospheres. In fact, Europa has the smoothest surface out of any solid body in our solar system, because it’s made up almost entirely of water ice. That alone is cool enough, but what exists underneath this shell of ice is even cooler… Well, not literally.
Beneath the shell lies a vast ocean of liquid water. Astronomers believe that this ocean is likely twice the volume of all of Earth’s oceans combined, with the highest estimate having it as around 100 miles deep. This ocean is where scientists hope to search for life, and it might be where they have luck. While the ocean is located a fair distance underneath the ice crust and is likely inaccessible to us with current technology, Europa is notable for having cryo-geysers that likely eject material from deep within the oceans. The European Space Agency and NASA are both in the process of sending missions to Europa in order to examine these geysers further, with NASA’s “Europa Clipper” already having been launched, and expected to arrive in the year 2030. While Europa Clipper will not land on the surface, it hopes to be able to analyze the plumes from deep within Europa from orbit, providing more information than we’ve ever had before on the matter.
Who knows if life will really be found in Europa’s oceans. But what better place to look than a giant ocean of liquid water? It seems to me like it’s a better spot than the rusty plains of Mars or the hellscape that is Venus! Maybe we’ll finally get lucky and answer one of the longest-running questions; “Are we alone in the universe?”
