Pluto’s biggest satellite Charon might have once harbored a subterranean ocean of liquid water. According to a NASA-funded study, it’s possible that the icy surface of Charon is cracked, which means its interior was once warm enough to maintain a subsurface ocean of liquid water. Pluto, a one-time planet, is now characterized as a “dwarf planet.” Today, the planet and all its moons have a bitterly cold environment with -229?C, where there is no possibility of any liquid water.

Pluto Charon

‘New Horizons’ spacecraft to reach Pluto next year

Anyway, it could only be probed after NASA’s New Horizons spacecraft reaches Pluto and Charon in July next year. Scientists have discovered that two frigid moons with cracked surfaces, Jupiter’s Europa and Saturn’ Enceladus have underground oceans. The cracked surface of Charon could show the same thing. Charon probably doesn’t support a liquid ocean today. But friction created by tidal forces long ago could have warmed its interior.

Alyssa Rhoden of NASA’s Goddard Space Flight Center said that her model predicts different fracture patterns on the surface of Pluto’s biggest moon. By comparing her predictions to the actual observations of New Horizons, NASA could discover if Charon ever had a subsurface ocean, driven by high eccentricity. Researchers believe the tidal forces that warmed Charon’s interior would have been created by the moon’s very eccentric orbit in the past.

Scientists have discovered five moons orbiting Pluto

Charon was probably formed after a giant impact blasted Pluto’s pieces off into space. Those little pieces initially orbited the dwarf planet, subsequently coalescing into the moons, NASA scientists said. Besides Charon, there are four other moons orbiting Pluto. NASA said in a statement that there would have been tides on the moon as well as its parent planet as gravitational tug-of-war caused their surfaces to bulge toward each other. It flexes the interiors of the moon and generates friction. Researchers believe this tidal heating had kept Charon’s interiors warm and subsurface oceans liquid.

Rhoden said Charon’s orbit around Pluto is very much circular today, eliminating the possibility of the moon still having a liquid underground ocean.