NASA Satellite Finds Interior of Mars Is Colder

New observations from NASA's Mars Reconnaissance Orbiter indicate that the crust and upper mantle of Mars are stiffer and colder than previously thought. 

The findings suggest any liquid water that might exist below the planet's surface, and any possible organisms living in that water, would be located deeper than scientists had suspected. 

"We found that the rocky surface of Mars is not bending under the load of the north polar ice cap," said Roger Phillips of the Southwest Research Institute in Boulder, Colo. Phillips is the lead author of a new report appearing in this week's online version of Science. "This implies that the planet's interior is more rigid, and thus colder, than we thought before." 

The discovery was made using the Shallow Radar instrument on the spacecraft, which has provided the most detailed pictures to date of the interior layers of ice, sand and dust that make up the north polar cap on Mars. The radar images reveal long, continuous layers stretching up to 600 miles (1,000 kilometers), or about one-fifth the length of the United States. 

"In our first glimpses inside the polar ice using the radar on Mars Reconnaissance Orbiter, we can clearly see stacks of icy material that trace the history of Mars' climate," said Jeffrey Plaut of NASA's Jet Propulsion Laboratory, Pasadena, Calif. Plaut is a science team member and a co-author of the paper. "Radar has opened up a new avenue for studying Mars' past."