NASA Confirms Presence Of Water Ice On Mercury

Messenger's Wide Angle Camera imaged this never-before-seen patch of terrain near Mercury's North Pole during its first pass over the region after the camera was activated. At this point Mercury is just 280 miles above the surface. The spacecraft's elliptical orbit brings it as close as 125 miles from the surface and as far away as 9,300 miles. NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

Daytime on Mercury’s equator can break the 800-degree mark, but nonetheless there’s long been speculation that the first planet’s poles might be icy. A new analysis of neutron-spectrometry data returned by the Messenger probe confirms the hypothesis: there’s ice in some polar craters!

When radar detected brightness near Mercury’s poles in 1992, the prevailing theory and hope was that it was H2O, but there are other reflective substances it might have been: lovely white sand deserts, perhaps.

Messenger, the NASA probe that’s been orbiting Mercury for a couple of years now, analyzed neutrons coming from the planet, and noticed that the quantity was lower above the polar bright spots — exactly commensurate with the way water ice absorbs neutrons.

Time to build a Mercury colony.

[Science via New York Times]