NASA's twin robot geologists, the Mars Exploration Rovers, launched
toward Mars on June 10 and July 7, 2003, in search of answers about the history of water on Mars. They are scheduled to arrive on Mars January 3 and January 24 PST (January 4 and January 25 UTC).
The Mars Exploration Rover mission is part of NASA's Mars Exploration
Program, a long-term effort of robotic exploration of the red planet.
Primary among the mission's scientific goals is to search for and
characterize a wide range of rocks and soils that hold clues to past
water activity on Mars. The spacecraft are targeted to sites on opposite sides of Mars that appear to
have been affected by liquid water in the past. The landing sites are at Gusev Crater, a possible former lake in a giant impact crater, and Meridiani Planum, where mineral deposits (hematite) suggest Mars had a wet past.
After the airbag-protected landing craft settle onto the surface and
open, the rovers will roll out to take panoramic images. These will give
scientists the information they need to select promising geological targets
that will tell part of the story of water in Mars' past. Then, the rovers will
drive to those locations to perform on-site scientific investigations over the
course of their 90-day mission.
These are the primary science instruments to be carried by the rovers:
- Panoramic Camera (Pancam): for determining the mineralogy, texture,
and structure of the local terrain.
- Miniature Thermal Emission Spectrometer (Mini-TES):
for identifying promising rocks and soils for closer examination and for
determining the processes that formed Martian rocks. The instrument will
also look skyward to provide temperature profiles of the Martian atmosphere.
- Mössbauer Spectrometer (MB):
for close-up investigations of the
mineralogy of iron-bearing rocks and soils.
- Alpha Particle X-Ray Spectrometer (APXS):
for close-up analysis of the
abundances of elements that make up rocks and soils.
for collecting magnetic dust particles. The Mössbauer Spectrometer and
the Alpha Particle X-ray Spectrometer will analyze the particles
collected and help determine the ratio of magnetic particles to non-magnetic
particles. They will also analyze the composition of magnetic minerals in
airborne dust and rocks that have been ground by the Rock Abrasion Tool.
- Microscopic Imager (MI): for obtaining close-up, high-resolution images
of rocks and soils.
- Rock Abrasion Tool (RAT):
for removing dusty and weathered rock
surfaces and exposing fresh material for examination by instruments onboard.
A goal for the rover is to drive up to 40 meters
(about 44 yards) in a single day, for a total of up to one 1
kilometer (about three-quarters of a mile).
Moving from place to place, the rovers will perform on-site geological
investigations. Each rover is sort of the
mechanical equivalent of a geologist walking the surface of Mars. The
mast-mounted cameras are mounted 1.5 meters(5 feet) high
and will provide 360-degree, stereoscopic, humanlike views of the
terrain. The robotic arm will be capable of movement in much the same
way as a human arm with an elbow and wrist, and will place instruments directly up against rock
and soil targets of interest. In the mechanical "fist" of the
arm is a microscopic camera that will serve the same purpose as a
geologist's handheld magnifying lens. The Rock Abrasion Tool serves the purpose of
a geologist's rock hammer to expose the insides of rocks.