Mars Global Surveyor NASA’s Mars Global Surveyor spacecraft, which has
collected more information about the red planet than all
previous missions combined, completes its primary science
mission today and begins a new era of continued exploration.

“By any conceivable measure the scientific impact of Mars
Global Surveyor has been extraordinary. In many ways we now
know Mars to be a different planet than when the spacecraft
arrived in 1997, and our perspective continues to evolve as
the data keep flowing,” said Dr. Arden Albee, Global Surveyor
project scientist at the California Institute of Technology in
Pasadena. “In some aspects, we now have better maps of Mars
than we do of Earth.”

During the primary science mission, the spacecraft
studied the climate, surface topography and subsurface
resources and mapped the entire planet,” said Tom Thorpe,
Global Surveyor project manager at NASA’s Jet Propulsion
Laboratory, Pasadena, Calif. “The extended mission will
continue to take advantage of these extraordinary mapping
capabilities and the data will be used to select future
landing sites for several upcoming missions.”

Mars Global Surveyor’s extended mission has been approved
through April 2002.

The robotic orbiter was launched on Nov. 7, 1996, and
arrived at Mars on Sept. 12, 1997. The spacecraft began its
primary mapping mission in March 1999 and has collected data
for a full Martian year, equivalent to about two Earth years.
Those comprehensive observations are proving invaluable to
understanding the seasonal changes on Mars.

Some of the most significant findings of the mission include:

— Enticing evidence for recent liquid water at the Martian

— Dramatic evidence for layering of rocks that points to
widespread ponding of water or lakes on Mars in its early

— The first good estimate of the amount of water currently
trapped in both Martian polar caps combined — about one and a
half times the amount of ice in Greenland.

— Topographic evidence for a South Pole-to-North Pole slope
that controlled the transport of water and sediments, and
recognition of the flat Northern Hemisphere that has been
proposed as the possible site of an ancient ocean.

— The surprising detection of highly magnetized crust in the
Southern Hemisphere, which indicates rapid cooling of Mars in
the beginning of its history that may have contributed to its
earlier, warmer climate.

— The first reliable models of the crustal structure of Mars,
including the detection of ancient impact basins and possible
channels buried beneath the northern plains.

— Identification of the mineral hematite, indicating a past
surface-hydrothermal environment that may be an analog for the
kinds of areas in which early life developed on Earth.

— Significantly improved understanding of the dynamics of the
atmosphere, including the monitoring of cyclonic storms, and
the daily and seasonal behavior of carbon dioxide and water
ice clouds.

— Extensive evidence for the role of dust in re-shaping the
recent Martian environment in the form of dust devils, dust
storms, dunes and sand sheets.

As of 4:33 p.m. PST (7:33 p.m. EST) January 31, 2001, the
spacecraft will have made 8,505 orbits of the planet and taken
more than 58,000 images, 490 million laser-altimeter shots to
measure topography and 97 million spectral measurements.

The Global Surveyor mission is managed by JPL for NASA’s
Office of Space Science, Washington, D.C. Lockheed Martin
Astronautics, Denver, Colo., developed and operates the
spacecraft. JPL is a division of the California Institute of

Additional information on the mission can be found at: