4 January 2004
This picture is a composite of Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) daily global images acquired at Ls 145° during a previous Mars year. This month, Mars looks similar, as Ls 145° occurs in mid-January 2005.
This picture shows the Tharsis face of Mars. Over the course of the month, additional faces of Mars as it appears at this time of year are being posted for MOC Picture of the Day.
Ls, solar longitude, is a measure of the time of year on Mars. Mars travels 360° around the Sun in 1 Mars year. The year begins at Ls 0°--the start of northern spring and southern summer. In January 2005, it is northern summer and southern winter. The seasons on Mars occur according to Ls, described in the following table:
Ls | Season |
0° - 90° | northern spring, southern autumn |
90° - 180° | northern summer, southern winter |
180° - 270° | northern autumn, southern spring |
270° - 360° | northern winter, southern summer |