This figure shows the first ever atmospheric temperature profile measured from the top of the Mars atmosphere all the way to the surface. It was made using the combination of a temperature measurements derived from the Mars Global Surveyor thermal emission spectrometer (lines) and temperature measurements from the Mars Exploration Rover Opportunity’s miniature thermal emission spectrometer instrument (dots). The orbiter’s instrument can measure the temperature downward from the top of the atmosphere, but cannot see accurately all the way to the ground. From its position on the martian surface, the rover’s instrument can measure the temperature looking upward, but can only see to about 6 kilometers (4 miles) high. The region where these two measurements cross (about 4 to 6 kilometers or 2.5 to 4 miles above the martian surface) match very closely. The region also provides the first ever profile that extends from about 60 kilometers (37 miles) above the surface all the way down to the surface.