Astronomy Picture of the Day

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

March 15, 1999
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Happy Face Crater on Mars
Credit: Malin Space Science Systems, MGS, NASA

Explanation: Even Mars can put on a happy face. The Martian crater Galle has internal markings reminiscent of a smiley face symbol. Such markings were originally discovered in the late 1970s in pictures taken by the Viking Orbiter. A large meteor impacted the Martian surface to form the crater. Conventional wisdom holds that the markings inside the crater are placed by chance by natural processes. The Mars Global Surveyor (MGS) spacecraft currently orbiting Mars took the above picture. MGS recently started the global surveying phase of its mission.

Tomorrow's picture: S Marks the Sun

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Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (USRA)
NASA Technical Rep.: Jay Norris. Specific rights apply.
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& Michigan Tech. U.