New evidence from the Messenger spacecraft orbiting Mercury hints that the tiny planet may be harboring water ice in some of its most extreme terrain. The Messenger spacecraft has found that bright radar spots previously detected by the Arecibo Observatory in Puerto Rico appear to be in permanent shadow, according to camera views from the probe's Mercury Dual Imaging System (MDIS).
"We've never had the imagery available before to see the surface where these radar-bright features are located," Nancy Chabot, an instrument scientist for MDIS at the Johns Hopkins University Applied Physics Laboratory, said in a statement. "MDIS images show that all the radar-bright features near Mercury's south pole are located in areas of permanent shadow, and near Mercury's north pole such deposits are also seen only in shadowed regions, results consistent with the water-ice hypothesis."
The Daily Galaxy via space.com and nasa.gov/mission