Mars Pathfinder Data Summary
Mission Objectives
 Demonstrate the feasibility of low-cost landings on Mars
 Demonstrate the feasibility of low-cost exploration of the Martian surface
 Obtain atmospheric entry data
 Conduct long-range and close-up surface imaging
 Characterize the Martian environment for further exploration
“NASA’s Mars Pathfinder mission – the first spacecraft to land on Mars in more than 20
years and the first ever to send a rover out to independently explore the Martian
landscape – is set for touchdown July 4, initiating a new era of scientific exploration that
will lead eventually to human expeditions to the red planet.”
Mars Pathfinder Landing Press Kit, July 1997
Lander Instruments
 Imager for Mars Pathfinder (IMP)
 Meteorological Station
Rover Instruments
 Two stereo cameras in the front and a rear color imaging system; cameras
worked in tandem with a laser system to detect and avoid obstacles
 Alpha-Proton-X-Ray Spectrometer (APXS)
Data and imagery from the Mars Pathfinder mission follows.
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Geology
The image below summarizes different materials found on the Martian surface near the
Pathfinder landing site:
RED ARROWS: Point to rounded rocks, possibly shaped by the action of water.
BLUE ARROWS: Point to sharp-edged rocks, thought to be impact ejecta or volcanic.
Point to the light areas believed to be deposits left behind by
evaporating water.
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Alpha Proton X-Ray Spectrometer Results
Igneous rocks are usually classified according to the minerals they contain. In the
absence of mineralogic data, volcanic rocks can be classified using their chemical
compositions. Shown here is a scheme which classifies volcanic rocks on the basis of
their alkalis (Na2O and K2O) and silica (SiO2) contents. This commonly used chemical
classification for lavas shows that Barnacle Bill and Yogi (corrected for adhering dust)
are distinct from basaltic Martian meteorites (shown as red squares).
Meteorology
Temperatures measured from the top of the 1 meter mast on Mars Pathfinder varied
from daily highs of about 260 K (-13° C) to lows of 196 K (-77° C). This is about 10 K
degrees warmer than Viking 1 Lander measurements made at 1.6 meters.
Imaging of the sky and the sun at different elevations above the horizon showed the
atmosphere to be moderately dusty, consistent with what was seen by the Viking
Landers. Approximately 35% of direct sunlight at noon was scattered or absorbed by
dust. Visibility tended to be about 30 km. The dust appeared to be spread vertically high
into the atmosphere and globally distributed. The sky did not appear to have the clear
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skies postulated before the landing, but was hazy and salmon-colored, as it was for
Viking.
Extensive water-ice clouds were imaged in the pre-dawn hours by the Lander camera.
The clouds typically moved from the NE at about 7 meters per second (15 mph) and
would disappear right around sunrise. The clouds are thought to consist of frozen water
condensed around dust particles.
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360° panoramic image of the Pathfinder landing site in Ares Vallis.
True color image of pre-dawn clouds in the eastern sky. This image was acquired at 05:13 local solar time on Sol 39.
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The Sojourner rover awaits deployment on the Pathfinder landing system.
The Sojourner rover takes spectroscopic data from a large rock near the lander.
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Sojourner rover image of the rock “Half Dome.”
Sojourner rover image of the rock “Moe.”
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