Saturn's moon Titan has a mysterious ice formation that stretches nearly halfway across its massive surface.
Scientists, who are unsure what type of geologic feature the ice block may indicate, based their new research on data gathered from NASA's Cassini spacecraft, which spent 13 years examining the Saturn system.
"It's a good example of how we're doing really well at continuing to mine these amazing Cassini data for new results," Jani Radebaugh, a planetary scientist at Brigham Young University who wasn't involved in the new research, told Space.com. "We're far from being finished with understanding Titan to the degree we can with Cassini."
Titan, which is 50 percent larger than Earth's Moon, has an atmosphere that's rich in nitrogen – and contains some methane, hydrogen and other gases – where liquids made of organic compounds rain down on its surface. The moon's surface temperature is a bone-chilling −179.2 degrees Celsius, and Titan only receives 0.1 percent of the light that the Earth gets.
"What we're curious about is, beyond that global gentle snowfall of organics, what's happening?" Radebaugh told Space.com. "It can be really hard to see through that layer to be able to see what's going on."
Researchers used a technique called principal component analysis, which allows them to pick up on smaller elements in the data that might be overlooked otherwise, according to Space.com.
Still, scientists said more research is needed to discover what exactly caused the uncovered ice on Titan's surface.
"It's a big feature that tells us something about the way that Titan was in the past, but we don't know really what it is," lead author Caitlin Griffith, a planetary scientist at the University of Arizona, told Space.com. "I think right now it's basically telling us that it's complicated, the surface is fairly complicated."
The research is described in a paper published in the journal Nature Astronomy.