Europa and Enceladus are two ocean moons that scientists have concluded have liquid water oceans underneath their outer icy shells. The Europa Clipper mission should reach Europa around April of 2030. If it collects data hinting at the moon’s potential habitability, robotic lander missions could be the only way to confirm if there’s really life in there or not.
To make these lander missions happen, NASA’s Jet Propulsion Laboratory team has been working on a robot that could handle the search for life and already tested it on the Matanuska Glacier in Alaska. “At this point this is a pretty mature concept,” says Kevin Hand, a planetary scientist at JPL who led this effort.
Into the unknown
There are only a few things we know for sure about conditions on the surface of Europa, and nearly all of them don’t bode well for lander missions. First, Europa is exposed to very harsh radiation, which is a problem for electronics. The window of visibility—when a potential robotic lander could contact Earth—lasts less than half of the 85 hours it takes for the moon to complete its day-night cycle due to the Europa-Jupiter orbit. So, for more than half the mission, the robot would need to fend for itself, with no human ground teams to get it out of trouble. The lander would also need to run on non-rechargeable batteries, because the vast distance to the Sun would make solar panels prohibitively massive.
And that’s just the beginning. Unlike on Mars, we don’t have any permanent orbiters around Europa that could provide a communication infrastructure, and we don’t have high-resolution imagery of the surface, which would make the landing particularly tricky. “We don’t know what Europa’s surface looks like at the centimeter to meter scale. Even with the Europa Clipper imagery, the highest resolution will be about half a meter per pixel across a few select regions,” Hand explains.
