Icy Darkness

This image combines observations from ground-based radio telescopes and the MESSENGER spacecraft to depict possible locations of ice deposits near the north pole of the planet Mercury. Red, from MESSENGER, shows regions that are in perpetual shadow, so they are especially cold. Yellow, from ground-based radio telescopes, shows possible exposed ice deposits. The Moon may have similar ice deposits near its poles. [NASA/JHUAPL/CIW/NAIC/Arecibo]