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 19, 1995
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The Mountains of Mars
Picture Credit: NASA,Viking Project

Explanation: Volcanic activity on Mars has produced towering mountains. The largest one, Olympus Mons, is pictured here in this Viking Orbiter image. Olympus Mons is a shield volcano nearly 15 miles high and over 300 miles wide at its base. By comparison, Earth's largest volcano, Mauna Loa in Hawaii, is just over 5 miles high and about 12 miles wide.

For more information about volcanic mountains on Mars see Calvin J. Hamilton's Mars page.

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.