TOPOGRAPHY OF THE POLAR ICE CAPS ON MARS: RECENT RESULTS FROM THE MARS ORBITER LASER ALTIMETER

The spacecraft exploration of the planet Mars in the last two decades provided scientists with an enormously rich data base. This talk presents some aspects of the Mars Orbiter Laser Altimeter (MOLA) investigation related to the advances on the knowledge of the Martian Polar Ice Caps. The MOLA instrument continues to function on board of the Mars Global Surveyor Spacecraft (MGS). Precise topographic grids compiled by the MOLA instrument allow us for the first time an access to the shape of some very interesting features. Polar ice caps and polar layered deposits are the major known reservoir of water on Mars. Their shape was very poorly known prior to the MGS mission. Cited errors were at 1km level MOLA measurements allowed us to reconstruct the shape of the ice caps down to less than 5m absolute error. It may be even possible to track changes in the seasonal snow cover. The evolution and origin of the residual ice caps and layered deposits are poorly understood. The layered deposits are thought to be a record of the climatic variations on Mars, which are possibly due to variations in the planet's orbit. Just like the core samples from the Antarctic, they can help us to look in to the past climate of Mars. We will discuss the current understanding of the subject polar cap evolution in the light of the recent topography and imagery taken by the instruments on board of the Mars Global Surveyor Spacecraft.

Abstract Co-Authored by the MOLA Science Team