This image shows the nighttime (2AM) temperatures measured by the Thermal Emission Spectrometer (TES) instrument on the Mars Global Surveyor wrapped on to a globe. The coldest temperatures (shown in purple) are -120C and the warmest temperatures (white) are -65C.
The view is centered on Isidis Planitia (15N, 270W), which is covered with warm material, indicating a sandy and rocky surface. The small, cold (blue) circular region to the right is the Elysium volcanoes, which are covered in dust that cools off rapidly at night. At this season the north polar region is in full sunlight as is relatively warm at night. It is winter in the southern hemisphere and the temperatures are extremely low(~-120C).