86.5°N, 324.0°W --- 16 December 2000 --- illuminated from lower left 10 km (6.2 mi) wide by 3 km (1.9 mi) high
85.7°N, 307.9°W --- 2 December 2000 --- illuminated from upper left 2 km (1.2 mi) wide by 0.9 km (0.6 mi) high
87.0°N, 263.8°W --- 12 December 2000 --- illuminated from upper left 10 km (6.2 mi) wide by 3 km (1.9 mi) high
On Mars, Northern Hemisphere Summer (and Southern Hemisphere Winter) began on December 16, 2000. In this December holiday season, many children across the U.S. and elsewhere are perhaps anticipating an annual visit from a generous and jolly red-suited soul from the Earth's North Pole. As the December holidays were approaching, the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) was busy acquiring new views of the region around the martian north pole. The three best views obtained this month are shown here. The top (A) and bottom (C) views show many layers exposed and eroded into the form of ridges and troughs on shallow slopes within the martian north polar cap. The middle (B) view is a picture of the rugged, eroded polar ice cap surface itself. The layers are believed to have formed over tens to hundreds of thousands of years by deposition of dust and ice each cold martian winter. These surfaces today all appear to have been eroded. The brightest material in each image is frost--temperatures at this time of year indicate that the frost is composed of frozen water. In winter, temperatures can be cold enough to freeze carbon dioxide, as well.