Numerical Simulation of Convective Cells (IMAGE) Washington University in St. Louis Caption Computer simulations show that Pluto's Sputnik Planum is covered with icy, churning, convective "cells" 10-30 miles across, and less than a million years old. The scene above, which is about 100 miles (165 kilometers) across, is part of the highest resolution scan taken by the New Horizons spacecraft. The picture below shows a depth cross-section of what the convection pattern in the nitrogen ice layer might look like, with warmer nitrogen ice (in red) rising to the surface and spreading out, then cooling (in blue) and descending back to the bottom of the layer. Credit NASA/JHUAPL/Southwest Research Institute/Washington University Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.