Mars Crater
NASA’s Mars Global Surveyor camera recently captured four
wide-angle pictures of craters in both the northern and
southern middle and polar latitudes of Mars that demonstrate
how the camera is used to monitor changes in Martian weather
and the seasonal coming and going of polar frost.

It is spring in the Northern Hemisphere, and frost that
accumulated during the most recent six-month-long winter has
been retreating since May. Examples of frost-rimmed craters
include Lomonosov and an unnamed crater farther north. It is
autumn in the Southern Hemisphere, and frost was seen as early
as August in some craters, such as Barnard; later the frost
line moved farther north, and frost began to appear in Lowell
Crater in mid-October.

The images are available at or
or .

Mars Global Surveyor is managed by NASA’s Jet Propulsion
Laboratory, Pasadena, Calif. JPL is a division of the
California Institute of Technology in Pasadena. Malin Space
Science Systems, San Diego, built and operates the camera
system. JPL’s industrial partner is Lockheed Martin
Astronautics, Denver, which developed and operates the