Europa, the large icy moon of Jupiter, is one of the more interesting worlds in the solar system because scientists believe that an ocean of liquid water–which could harbor life–may exist beneath the moon’s icy crust. Reaching any ocean, though, will require drilling through perhaps tens of kilometers of ice, a challenge here on Earth, let alone on a distant world. The BBC reports that a German team had developed a prototype for a system that could work there: a probe with an electrically-heated tip could slowly melt its way through the ice to reach the ocean below. During a test in Antarctica, the prototype made it to a depth of 220 meters in 75 hours.