Sputnik Planitia is a large, partially glaciated basin on Pluto. About 1,400 by 1,200 km in size, Sputnik Planitia is partially submerged in large, bright glaciers of nitrogen ice. From Wikipedia
A recent study reveals that Pluto's iconic heart-shaped structure, Sputnik Planitia, formed from a slow, oblique collision with a planetary body, challenging previous theories of a subsurface ocean.
