Mysterious nitrogen ice patterns on Pluto linked to sublimation
Scientists use modelling to show that sublimation of nitrogen ice fuels convection in Pluto’s Sputnik Planitia impact crater by cooling its surface
An international team, including researchers from École normale supérieure (ENS) in Lyon, France and the University of Exeter in the UK, has figured out why an impact crater on the surface of Pluto called Sputnik Planitia is filled with nitrogen ice that is surprising polygonal in shape. The scientists were able to show that this astonishing pattern of flat polygons separated by narrow troughs is formed by ice sublimation, a process by which the ice turns directly into gas without going through a liquid state. The team concluded that this sublimation is what seems to power convection in the ice layer of Sputnik Planitia by cooling down its surface.