Mars Orbiter Laser Altimeter News 12 Jan 2001
MOLA is the Mars Orbiter Laser Altimeter, an instrument currently in orbit around Mars on the Mars Global Surveyor (MGS) spacecraft. The instrument transmits infrared laser pulses towards Mars at a rate of 10 Hz and measures the time of flight to determine the range of the MGS spacecraft to the Martian surface. The range measurements are used to construct a precise topographic map of Mars that has many applications to studies in geophysics, geology and atmospheric circulation.
MOLA maps with major surface features labeled are now available here:
http://ltpwww.gsfc.nasa.gov/tharsis/map_lab.html
Top 10 Scientific Achievements from MOLA
http://ltpwww.gsfc.nasa.gov/tharsis/mola.top10.html
On January 31, 2001, Mars Global Surveyor will complete its primary mapping mission of Mars. The mapping mission consists of the spacecraft observing Mars continuously for one full Mars year (687 days), in order to globally map the planet and monitor seasonal changes. Fortunately, the spacecraft and instruments are still healthy and collecting excellent data. NASA has recognized the importance of MGS’s contribution to Mars science and has approved an extended mission that will commence directly after the mapping mission. So MOLA data will keep flowing. But in light of the end-of-mapping mission milestone, the MOLA Science Team has collectively looked back at the scientific advances enabled by MOLA observations and made a list of the "top 10". Believe it or not, there was almost no argument about the items on the list, which are presented in no particular order.
(1) The most accurate global topographic map of any planet in the solar system, including a two-order-of-magnitude improvement in the geodetic grid (latitude/longitude system) of Mars.
(2) Recognition of the flat northern hemisphere of Mars.
(3) The pole-to-pole slope and Tharsis control the shape of the planet.
(4) Detection of buried basins beneath the northern hemisphere plains that has clarified the large impact basin population.
(5) The first reliable inversion for the crustal structure of Mars (using both MOLA and MGS gravity data from the Radio Science Experiment).
(6) Establishment of the pathways for the flow of past water and the locations, sizes, and volumes of watersheds.
(7) All craters greater than a few kilometers in size display ramparts, indicating that water was pervasive in the Martian subsurface.
(8) Present-day surface water inventory from polar cap/layered terrain volumes.
(9) Detection of the heights of clouds and identification of dynamical features in the atmosphere, such as gravity waves.
(10) Stay tuned. Paper to be submitted shortly.
MOLA Science Team
