Frosted Southern Plains in Early Spring
The Martian southern hemisphere was nearly 2 months into its spring season when this picture was taken by the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) on September 25, 1999. The scene covers a vast, frost-coated plain south of the Martian antarctic circle. The icy terrain in the image has an almost pastel-like character, owing to the mixture of reddish dust both on, in, and under the white frost. The frost--mostly frozen water at this time of year--is left over from winter, which ended August 2, 1999. One martian year is about 687 Earth days long, thus each of the planet's four seasons are nearly twice as long as seasons on Earth. The largest crater in the upper left is Lau Crater, named for the Danish astronomer, Hans E. Lau (1879-1918). The dark spot near the center of the image has no name, and its origin is unknown. The picture covers an area about 1,020 km (634 mi) across by approximately 1,240 km (771 mi) down. The center is located near 76°S, 97°W, and north is toward the upper right. Sunlight illuminates the scene from the upper left. This is a color composite of M07-04748 (red) and M07-04749 (blue) wide angle MOC images. To see what the raw MOC image data look like, visit the newest data releases (for Mission Subphases M07 - M12, covering September 1999 through February 2000) in the MOC GALLERY.