Astronomy Picture of the Day

Discover the cosmos! Each day we feature a different image or photograph of our fascinating universe, along with a brief explanation written by a professional astronomer.

November 28, 1995

Shadow at the Lunar South Pole
Credit: Clementine, BMDO, NRL, LLNL

Explanation: In 1994, the space probe Clementine spent 70 days in lunar orbit mapping the Moon's surface. Shown above is a dramatically detailed composite view centered on the Moon's South Pole constructed from 1500 Clementine images. The top half shows the part of the Moon which faces the Earth while the bottom half is the lunar Farside. The images reveal a major depression very near the South Pole itself, probably caused by the impact of a comet or asteroid. The shadow region near the impact site is extensive and may be permanent - creating an area cold enough to trap water of cometary origin as ice.

Tomorrow's picture: Releasing Compton

Authors & editors: Robert Nemiroff (GMU) & Jerry Bonnell (USRA).
NASA Technical Rep.: Sherri Calvo. Specific rights apply.
A service of: LHEA at NASA/ GSFC