New evidence of a deep ocean on Pluto

May 21. () –

Mathematical models to explain cracks and bulges observed by NASA’s New Horizons mission in Pluto’s Sputnik basin support the existence of an ocean at great depth.

This basin was the site of a meteorite collision billions of years ago. Calculations by Patrick McGovern, of the Lunar and Planetary Institute (LPI) and Alex Nguyen, a doctoral candidate at Washington University in St. Louis, indicate that the ocean in this area exists beneath a layer of water ice 40 to 80 kilometers thicka protective blanket that likely prevents the inland ocean from freezing.

They also calculated the likely density or salinity of the ocean based on fractures in the ice above. They estimate that Pluto’s ocean is, at most, about 8% denser than Earth’s seawater. Their findings are published in the journal Icarus.

As Nguyen explained, that level of density would explain the abundance of fractures observed on the surface. If the ocean were significantly less dense, the ice sheet would collapse, creating many more fractures than actually observed. If the ocean were much denser, there would be fewer fractures. “We estimate a sort of Goldilocks zone where the density and thickness of the crust are just right,” he said. it’s a statement.

For many decades, planetary scientists assumed that Pluto could not support an ocean. The surface temperature is about -220°C, a temperature so cold that even gases such as nitrogen and methane freeze. Water shouldn’t stand a chance.

“Pluto is a small body,” Nguyen said. “It should have lost almost all of its heat shortly after forming, so basic calculations would suggest it is frozen to its core.”

But following the flyby of Pluto by NASA’s New Horizons mission, prominent scientists have gathered evidence suggesting that Pluto likely contains an ocean of liquid water beneath the ice. That inference came from several lines of evidence, including Pluto’s cryovolcanoes that spew ice and water vapor. Although there is still some debate, “it is now generally accepted that Pluto has an ocean”, Nguyen said.