Radar-Bright Deposits in Mercury's North Polar Region

MESSENGER's highly eccentric orbit, which passes low over Mercury's north polar region, enables higher-resolution views of Mercury's surface in the north than in the south. Shown here is a subset of this image; the large 100-km diameter crater in the center is located at 72.5° N, 67.4° E and was recently named Stieglitz, for the American photographer Alfred Stieglitz. Of particular note are the craters hosting radar-bright features at low latitudes, extending southward to 67° N, and the many small craters that host radar-bright deposits. Low-latitude and small craters provide thermally challenging environments for water ice to persist. A thin (few tens of centimeters thick) layer of insulation is likely required to cover and to lower the temperature of these deposits if they are water ice. However, the smallest craters and the lowest-latitude locations may prove a challenge for water ice stability over extended periods of geologic time even with such cover.

Instrument: Wide Angle Camera (WAC) of the Mercury Dual Imaging System (MDIS)

Image credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

Note: For a similar image showing a wide-area map of the north polar region, see PIA15530: Radar-bright Deposits near Mercury's North Pole.