Mission Type: Rover: "Sojourner" Launch: December 4, 1996 UTC Launch Vehicle: Delta II Launch Location: Cape Canaveral Air Force Station, Florida Landing: July 4, 1997 Landing Site: Ares Vallis, Mars End of Mission: September 27, 1997
Mars Pathfinder was launched December 4, 1996 and landed on Mars' Ares Vallis on July 4, 1997. It was designed as a technology demonstration of a new way to deliver an instrumented lander and the first-ever robotic rover to the surface of the red planet. Pathfinder not only accomplished this goal but also returned an unprecedented amount of data and outlived its primary design life.
Both the lander and the 23-pound (10.6 kilogram) rover carried instruments for scientific observations and to provide engineering data on the new technologies being demonstrated. Included were scientific instruments to analyze the Martian atmosphere, climate, geology and the composition of its rocks and soil. Mars Pathfinder used an innovative method of directly entering the Martian atmosphere, assisted by a parachute to slow its descent through the thin Martian atmosphere and a giant system of airbags to cushion the impact.
NASA's Sojourner rover and undeployed ramps onboard the Mars Pathfinder spacecraft can be seen in this image, by the Imager for Mars Pathfinder (IMP) on July 4, 1997 (Sol 1).
Pathfinder's Airbag Landing
From landing until the final data transmission on September 27, 1997, Mars Pathfinder returned 2.3 billion bits of information, including more than 16,500 images from the lander and 550 images from the rover, as well as more than 15 chemical analyses of rocks and soil and extensive data on winds and other weather factors. Findings from the investigations carried out by scientific instruments on both the lander and the rover suggest that Mars was at one time in its past warm and wet.
Artist's Concept of Pathfinder's Airbag Landing
Rover Sojourner & "Yogi"
This 1997 image from NASA's Mars Pathfinder shows a close up of Sojourner as it placed its Alpha Proton X-Ray Spectrometer (APXS) upon the surface of the rock 'Yogi.'
The lander, formally named the Carl Sagan Memorial Station following its successful touchdown, and the rover, named Sojourner after American civil rights crusader Sojourner Truth, both outlived their design lives — the lander by nearly three times, and the rover by 12 times.
Mars Pathfinder Science Instruments
Alpha Proton X-ray Spectrometer: Determined the elemental composition of rocks and soils.
Three Cameras: provided images of the surrounding terrain for geological studies, and documented the performance and operating environment for Pathfinder mission technologies.
Atmospheric Structure Instrument/Meteorology Package: Measured the Martian atmosphere during Pathfinder's descent to the surface, and provided meteorological measurements at the lander.
Top Mars Pathfinder Science Findings
Rounded pebbles and cobbles at the landing site, and other observations, suggested conglomerates that formed in running water during a warmer past in which liquid water was stable.
Radio tracking of Mars Pathfinder provided a precise measure of the lander's location and Mars' pole of rotation. The measurements suggested that the radius of the planet's central metallic core is greater than 800 miles (1,300 kilometers) but less than roughly 1,250 miles (2,000 kilometers).
Airborne dust is magnetic, and its characteristics suggest the magnetic mineral is maghemite, a very magnetic form of iron oxide, which may have been freeze-dried on the particles as a stain or cement. An active water cycle in the past may have leached out the iron from materials in the crust.
Dust devils were seen and frequently measured by temperature, wind and pressure sensors. Observations suggested that these gusts are a mechanism for mixing dust into the atmosphere.
Early morning water ice clouds were seen in the lower atmosphere.
Abrupt temperature fluctuations were recorded in the morning, suggesting that the atmosphere is warmed by the planet's surface, with heat convected upward in small eddies.
This image from NASA's Mars Pathfinder has been rotated so that the main points of interest, which are the 'Rock Garden,' the rover Sojourner and the rock 'Yogi,' are visible arching across the upper hemisphere.
Yogi' is a meter-size rock about 5 meters northwest of NASA's Mars Pathfinder lander and was the second rock visited by the Sojourner Rover's alpha proton X-ray spectrometer (APXS) instrument. 3D glasses are necessary to identify surface detail.
Yogi' is a meter-size rock about 5 meters northwest of NASA's Mars Pathfinder lander and was the second rock visited by the Sojourner Rover's alpha proton X-ray spectrometer (APXS) instrument. Sol 1 began on July 4, 1997.
Image of NASA's Pathfinder Lander on Mars taken from Sojourner Rover left front camera on sol 33. The IMP (on the lattice mast) is looking at the rover. Airbags are prominent, and the meteorology mast is shown to the right. Sol 1 began on July 4, 1997.
Based on the first direct measurements ever obtained of Martian rocks and terrain, scientists on NASA's Mars Pathfinder mission report in this week's Science magazine that the red planet may have once been much more like Earth.
The Twin Peaks are modest-size hills to the southwest of the Mars Pathfinder landing site. They were discovered on the first panoramas taken by NASA's IMP camera on the 4th of July, 1997. Sol 1 began on July 4, 1997.
In 1997, NASA's Mars Pathfinder took this image of 'Shark' (upper left center), 'Half Dome' (upper right), and a small rock (right foreground) revealing textures and structures not visible in lander camera images.
Pebbles are seen in lander images, along with cobbles. For example, this image taken by NASA's Imager for Mars Pathfinder (IMP) shows the same pebbles that were visible in the Sojourner rover image of the 'Cabbage Patch.' Sol 1 began on July 4, 1997.
This color image shows NASA's Mars Pathfinder (MPF) Sojourner rover's Alpha Proton X-ray Spectrometer (APXS) deployed against the rock 'Moe' on the morning of Sol 65. This image was taken by by NASA's Mars Pathfinder (MPF).
This is the right image of a stereo pair taken by NASA's Sojourner rover in the area behind the 'Rock Garden' at the Pathfinder landing site and gives a view of the Martian surface not seen from the lander. Sol 1 began on July 4, 1997.
This is a close-up of the sunset on Sol 24 as seen by NASA's Imager for Mars Pathfinder (IMP). The red sky in the background and the blue around the Sun are approximately as they would appear to the human eye. Sol 1 began on July 4, 1997.
Details of one of Pathfinder's deflated airbags adjacent to a lander petal are prominent in this image, taken by NASA's Imager for Mars Pathfinder (IMP). The blue tiles on top of the petal are solar cells that are used to give power to the lander.
This is an image of the rover Sojourner at the feature called Mermaid Dune at the MPF landing site. Mermaid is thought to be a low, transverse dune ridge, with its long (approximately 2 meters) axis transverse to the wind.
This image was taken by the Imager for NASA's Mars Pathfinder about one minute after sunset on Mars on Sol 21. The prominent hills dubbed 'Twin Peaks' form a dark silhouette at the horizon, while the setting sun casts a pink glow over the darkening sky.
This image features a different perspective of one of the first pictures taken by the Imager for Mars Pathfinder (IMP) lander shortly after its touchdown at 10:07 AM Pacific Daylight Time on July 4. Sol 1 began on July 4, 1997.