Underwater snow on Earth gives clues about Europa's icy shell

Studying a bizarre underwater snow below ice shelves on Earth can help understand the ice shell Jupiter's moon Europa, according to researchers.

Europa is a rocky world about the size of the Earth's moon that is surrounded by a global ocean and a miles-thick ice shell. Below Europa's thick icy crust is a massive, global ocean where the snow floats upwards onto inverted ice peaks and submerged ravines.

The underwater snow is much purer than other kinds of ice, which means Europa's ice shell could be much less salty than previously thought, revealed the study published in the journal Astrobiology. The finding is important for mission scientists preparing NASA's Europa Clipper spacecraft, which will use radar to peek beneath the ice shell to see if Europa's ocean could be hospitable to life. Previous studies suggest the temperature, pressure and salinity of Europa's ocean nearest to the ice is similar to what you would find beneath an ice shelf in Antarctica.

The new information will be critical because salt trapped in the ice can affect what and how deep the radar will see into the ice shell, so being able to predict what the ice is made of will help scientists make sense of the data. Knowing what kind of ice Europa's shell is made of will also help decipher the salinity and habitability of its ocean, said the team from the University of Texas at Austin.