Jupiter’s moon Europa is roofed in bizarre pairs of ridges, they usually might come from the refreezing of shallow pockets of liquid water hiding throughout its icy shell
19 April 2022
Jupiter’s moon Europa is roofed in unusual pairs of parallel ridges. Now, researchers have discovered an identical function in Greenland and used it to unravel how such ridges kind – which can assist us perceive how Europa’s subsurface ocean interacts with its icy shell.
Europa has parallel pairs of ridges lots of of kilometres lengthy and lots of of metres excessive all throughout its floor, however it has been troublesome for researchers to elucidate how they took place as a result of we now have no direct knowledge on what’s going on underneath the floor.
“It’s a bit of a mystery to us at the moment what the structure of the ice shell is,” says Riley Culberg at Stanford University in California. “These double ridges are the most common surface feature that we see, so they have potential to be a particularly good way to understand the ice shell more generally.”
Culberg noticed an identical pair of ridges in satellite tv for pc pictures of the Greenland ice sheet. He and his colleagues analysed how these shaped and located that it was because of pockets of liquid water throughout the ice sheet. When a few of that water refreezes, it expands, creating cracks within the floor and pressurising the remaining water, which pushes upwards on both aspect of the refrozen part. That upwelling causes the parallel ridges.
If the identical course of creates the ridges throughout Europa, that suggests that there’s shallow water inside its 20 to 30-kilometre-thick shell of ice – one thing that has been steered earlier than, however by no means in reference to the ridges. “Double ridges are so common across the surface, you really have to have this shallow water pretty much everywhere,” says Culberg.
This is perhaps good for the prospect of life on Europa. “If there’s a lot of shallow water in the ice shell, it means that there has to be some amount of exchange between the ocean and the surface,” says Culberg. “That kind of movement allows for the mixing of chemistry and heat that you need in order for life to happen.” If there may be life in Europa’s ocean, it may additionally make its manner into these pockets of fluid, making it far simpler to search out, he says.
Journal reference: Nature Communications, DOI: 10.1038/s41467-022-29458-3
Sign as much as our free Launchpad publication for a voyage throughout the galaxy and past, each Friday
More on these subjects: