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.

July 21, 1995
See Explanation.  Clicking on the picture will download 
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The Search for Life on Mars
Picture Credit: NASA,Viking Project,

Explanation: Although images of Mars taken from space revealed the planet to have a barren and cratered surface, scientists did not give up the search for martian life. In 1976 NASA's Viking project succeeded in landing two robot probes on the surface of Mars. These landers were able to carry out sophisticated chemical experiments to look for signs of microscopic life in the martian soil. However, the experiments failed to produce any convincing evidence for life on Mars. Cameras onboard the Viking Landers also returned spectacular photos of the rocky martian landscape, like the one above, which showed no sign of martian animal or plant life.

For more information about the picture see The NSSDC Mars Photo Gallery.

The exploration of Mars is chronicled by the Center For Mars Exploration.


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Astronomy Picture of the Day is brought to you by Robert Nemiroff and Jerry Bonnell . Original material on this page is copyrighted to Robert J. Nemiroff and Jerry T. Bonnell.