In addition to a drill or cutter to extract samples, the team recommends that the lander include a camera system to see what’s going on outside, instruments for analyzing the chemistry of Europa’s icy crust, and something to monitor geologic activity, like a geophone.

“The important thing to remember is that this is intended to be a ‘bug hunt,’ this is designed to land in a place where based on the Europa flyby mission, there would be deposits from the ocean, organic materials, that sort of thing,” Lunine said. “So the intent is to use instruments that can detect the signs of life on those samples.” The team is especially interested in finding biosignatures— isotopes or molecules that suggest past or present life.

There are a few reasons why scientists have long been keen to hunt for life on Europa.


“Europa provisionally is a great place to go,” Lunine said. “It has a very large amount of rocks, it’s got a lot of heat [at its core], so at the base of the oceans there are undoubtedly hydrothermal systems. Everything we know about it makes this a good [place] to look for life.”

Doug Vakoch, president of METI International, which focuses on seeking out radio signals from more advanced extraterrestrial life, agrees that Europa is a great place to look, but feels that scientists probably won’t get many answers until they can extract samples straight from the ocean.


“To have the best chance of finding life on Europa, we’d love to be able to drill beneath the icy crust,” Vakoch told Gizmodo. “That won’t happen with the first lander that NASA is now discussing, which would dig down only four inches.”

That said, Vakoch is still very supportive of the 2031 mission and what it could find.


“The top priority of this lander mission will be to search for evidence of life on Europa,” he said. “But even if that main goal isn’t met, we will learn a great deal about the potential habitability of this icy moon, which will be essential for future, even more ambitious missions.”


Both Vakoch and Lunine noted the similarities between Europa and Saturn’s icy moon Enceladus. Enceladus also has a subterranean ocean beneath its crust, but unlike the Jovian moon, its south pole features geysers that constantly spew ocean water out into space—offering free samples, so to speak. Cassini discovered these geysers in 2005, and has since made several flybys through Enceladus’ south polar plume.

There are rumors that NASA is considering a mission to search for life on Enceladus, which could launch as early as 2025. With all these missions occurring over the next few decades, our chances of finding beyond outside Earth are looking better than ever.


“Where do we have a better chance of finding life—Europa or Enceladus?” Vakoch said. “At this point, it’s a tossup. Both deserve exploration, and I’d hate to have to choose between them. If we really want to understand the prospects for life arising in subsurface oceans, some day we need to go to both.”