This graph contains information about the surface temperature of Mars. Click on image for full size version (53K JPG) Image from: NASA/JPL

This image shows how cold the surface of Mars can be. The temperature was measured by the Mars Global Surveyor spacecraft. The scale to the left shows that purple regions are the coldest, about -170 degrees F (-113C), while the yellow areas are the warmest at about 17 degrees F (-8C). The surface of Mars may often become warmer than 17 degrees. Other data returned by Mars Global Surveyor shows the temperatures can be 30 degrees F (~0C) or more. These temperatures are very cold, however. The surface is either freezing cold or much colder than freezing. No wonder the water of Mars may be frozen into the ground! Freezing temperatures may have something to do with the thin atmosphere and lack of a greenhouse effect.

Temperature data from the surface of Mars is being returned everyday now that Mars Global Surveyor has reached Mars. Check the Mars Global Surveyor Image Archives or the Mars Global Surveyor Webpage, below, for sample data. Scientists are interested in learning if temperatures ever come above freezing for long period of time. This would affect theories about Martian water and climate. Recent Martian exploration is directed at these and other questions.