CASEY STATION, Antarctica — Near a nice, big hole in the ice and beneath the stone gray, midday Antarctic summer skies, six Adélie penguins stared at six men toiling with tools. The chasm in the ice might have been an inviting entry to the krill-rich waters below. None of the members of the tuxedoed recon party dove into the hole, a square about six feet across. The risk of leopard seals was just too great.

But had they leapt in, the penguins would have discovered not a seal, but a robot.

In November, scientists and engineers from NASA’s Jet Propulsion Laboratory successfully field tested Bruie — the “Buoyant Rover for Under-Ice Exploration” — beneath the ice of eastern Antarctica. The remotely operated rover was built to crawl along the underside of sea ice and ice shelves. These tests on Earth have a long-term goal of one day seeking evidence of life beneath the thick frozen shell covering Jupiter’s ocean moon of Europa. Beneath that ice is three times more liquid water than can be found in all the oceans on Earth.

[Sign up to get reminders for space and astronomy events on your calendar.]

It will be years before a spacecraft from Earth lands on Europa, which was most closely studied by NASA’s Galileo mission in the 1990s. The next robotic probe to visit that world will be Europa Clipper, scheduled to launch no sooner than 2025. When it arrives some years later, that spacecraft will orbit Jupiter and encounter Europa dozens of times at different angles to thoroughly scan and map the moon, considered one of the best candidates in our solar system to be inhabited by some form of extraterrestrial life.