Does Mars have mountains or did it have oceans? Carrie Straight 05.25.01 By using satellites orbiting Mars, astronomers took great pictures of the surface of the planet. One area, called the northern plains, is very flat ), except for these ridges that run across them. Scientists suggested that the northern plains might have been an ocean and the ridges the shoreline. Scientists from the United States wanted to test that theory. They measured the elevation (the height) of these ridges and the pattern of the ridge using the Mars Orbiter Laser Altimeter. The scientists realized that the ridges didn’t match the shorelines of an ancient ocean. The ridges correspond to where stress from volcanic, and tectonic activities probably occurred, so the scientists think that volcanic and tectonic processes, and not ocean waves, caused them. Withers, Paul, and Gregory A. Neumann. 2001. Enigmatic northern plains of Mars. Nature 410: 651. ©2001 The Aurora Collection, Inc. All Rights Reserved. Site Development by: Interactive Multimedia. Inc.