A salty sea could lurk beneath the heart of Pluto

Pluto

An ocean of salty water might lurk beneath Pluto’s Sputnik Planum, the left side of the dwarf planet’s famous heart, seen in this image from the New Horizons spacecraft.

NASA, JHUAPL, SWRI

A salty ocean more than 100 kilometers deep might lurk beneath Pluto’s icy heart, a new study suggests. The buried reservoir could have helped tip the dwarf planet over at some point in its past, bringing the heart-shaped region in line with gravitational forces from Charon, Pluto’s largest moon.

A subsurface ocean isn’t a new idea; researchers proposed the possibility in March to explain the alignment between Charon and Sputnik Planum — the frozen impact basin that forms the left side of Pluto’s heart. Brandon Johnson, a planetary scientist at Brown University, and colleagues ran computer simulations to estimate the thickness of the putative sea. They report their results online September 19 in Geophysical Research Letters

Christopher Crockett is an Associate News Editor. He was formerly the astronomy writer from 2014 to 2017, and he has a Ph.D. in astronomy from the University of California, Los Angeles.