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.

2000 April 25
See Explanation.  Clicking on the picture will download 
 the highest resolution version available.

Layers of the Martian South Polar Cap
Credit: Malin Space Science Systems, MGS, JPL, NASA

Explanation: The South Pole of Mars is stranger than was previously thought. Pictured above are unexpectedly complex layers photographed recently by the Mars Global Surveyor spacecraft currently orbiting Mars. The layers probably include carbon dioxide ice, water ice, rock and dust. The intricate structures might indicate erosion patterns that hold clues to the history of the Martian climate over the past 100 million years. The above image covers a region five kilometers across, resolving details as small as 25 meters across.

Tomorrow's picture: Cygnus Loop

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Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (USRA)
NASA Technical Rep.: Jay Norris. Specific rights apply.
A service of: LHEA at NASA/GSFC
& Michigan Tech. U.