The surface of Europa, one of Jupiter’s four main moons, is covered in a crust of ice 20 kilometers deep marked by mysterious dark double lines called linae. Now, a new study comparing the surface of Europa to the Earth’s icy crust of Greenland might shed some light on what those lines really are.
The moon Europa is covered in raised parallel lines hundreds of miles long. Each sector of the satellite’s surface is marked with a crisscrossing matrix of these double lines, but scientists have never known for sure how they formed.
This is where Greenland’s Double Ice Lines come in, which appeared regarding a decade ago and hide large pockets of water just below the surface. Scientists traversed Greenland’s ice crust using radar and scans showed water below the lines.
“This is the first time we’ve seen double lines like these on Earth,” Riley Culberg, a graduate student at Stanford University and lead author of the new study, told Space.com.