Magazine article Science News

Mars Views Hint at Early Land of Lakes

Magazine article Science News

Mars Views Hint at Early Land of Lakes

Article excerpt

For 30 years, ever since spacecraft recorded what appeared to be dried-up channels on Mars, scientists have sought to determine whether water ever flowed on the Red Planet. High-resolution images unveiled this week offer more evidence that parts of ancient Mars resembled a land of lakes. They also point out prime locations to look for fossils that would indicate life once existed on the planet.

The images, taken by the Mars Global Surveyor spacecraft, show in unprecedented detail that massive structures of layered rock, like Earth's Grand Canyon, are widespread on Mars. On Earth, such structures are made of sediments deposited over eons. The layers often sandwich fossils between them. Common at the site of dried-up lakes, these structures preserve our planet's ancient history.

In the Dec. 8 SCIENCE, Michael C. Malin and Kenneth S. Edgett of Malin Space Science Systems in San Diego report their analysis of the Surveyor images and argue that the Martian features also stem from water deposition.

Other mechanisms, such as fierce wind from a once-thick Martian atmosphere, could have sculpted the deposits, they caution. The team notes, however, that most of the layered topography resides in or near craters, which could have provided basins for standing water.

The locations of the structures "may be a good argument for water-laid sediments," agrees Harry Y. McSween Jr. of the University of Tennessee in Knoxville.

Although the layering of Martian rocks "has been well recognized since the days of Mariner 9" in 1969, the new images "have honed our information about where we should look next," notes Jim Garvin, NASA's Washington, D.C.-based project scientist for Mars exploration. He finds the idea of landing on the layered terrains to search for signs of the earliest Martian life "incredibly provocative. …

Search by... Author
Show... All Results Primary Sources Peer-reviewed


An unknown error has occurred. Please click the button below to reload the page. If the problem persists, please try again in a little while.