Mars Global Surveyor
While Spirit and Opportunity, Nasa's Mars Rovers are getting all
the attention, largely overlooked bonanzas of information about
the Red Planet are being reaped by the Mars Global Survey.
Originally launched for the first time successfully on September
12 1997, the Mars Global Surveyor has given Nasa much more than
its expectations by living beyond its primary mission which was
intended to end in January of 2002. Remaining in good condition
as of this point, Nasa has extended its mission for a third time
through 2006 and believe if funding is allocated the Surveyor
could remain in space around Mars' orbit for another five to ten
years. On September twelfth of this year, the Global Surveyor
passed Viking I as the longest lived spacecraft in Mars space
mission history.
Among the discoveries made by the Surveyor, the most dramatic
since its mission began was a discovery of a fossilized river
delta in a crater known as "Eberswalde". This delta proved the
existence of water flow among Mars at one time, resulting in the
production of sedimentary rock as found by Spirit and
Opportunity.
The most exciting recent discovery has been that of the
formation of new gullies on Mars. This evidence has changed the
estimates of the age of Mars. In addition, the Mars Global
Surveyor discovered a shrinking of the southern polar ice cap of
three feet a year. This proved to Nasa that Mars is undergoing
more frequent changed than previously believed. In addition, the
Surveyor has gathered data on the well-known dust storms of
Mars, showing them to be seasonal, varying, and covering only
part of the planet at a time. The dust storms were found to be
higher in the atmosphere than previously suspected. This meant
the surface of Mars is calmer than previously believed during
these interludes.
New technology has allowed Nasa to increase its utilization of
the Surveyor in ways never dreamed of at the onset of its
mission. Resolution of its cameras made it possible to determine
that boulders no larger than one to two meters exist in ripples
caused by a catastrophic flood. This technique, is known as
"compensated pitch and roll targeted observation". In May of
this year, the Surveyor again made history by being the first
spacecraft to ever take images of other spacecraft in orbit,
taking images of the European Space Agency's Mars Express and
NASA's Mars Odyssey.
Nasa - National Mars Exploration Program -
http://www.nasa.gov/home/: :
1) One Mars Orbiter Takes First Photos of Other Orbiters
2) Mars Orbiter Sees Rover Tracks Among Thousands of New Images
3) Nasa Press Releases September 20, 2005 4) Recent Changes on
Mars Seen by Mars Global Surveyor Michael C. Malin and Kenneth
S. Edgett, Malin Space Science Systems, September 2005