NASA Celebrates Mars Pathfinder Landing Anniversary
July 5, 2013

Mars Pathfinder Touched Martian Soil 16 Years Ago

Lee Rannals for - Your Universe Online

Independence Day not only marks the date on which America became a free nation, but also when NASA's Mars Pathfinder mission landed safely on Mars in 1997 allowing the US to stake its first claim on another planet.

Mars Pathfinder was carrying Sojourner, which was the first US Martian rover. The Soviet Union launched its Mars 3 rover in 1971, but communication was lost about 20 seconds after landing. Sojourner was the first successful rover mission, lasting from July until September 27, 1997.

The mission sent its first set of data back to NASA after 5:00 pm on July 4, 1997, followed by the release of images at 9:30 pm. The Sojourner rover spent the next three months relaying images and other data from Mars back to a lander. Sojourner had to communicate directly with Pathfinder, instead of Earth. The rover operated on the surface of Mars three times longer than expected and returned a tremendous amount of new information about the Red Planet.

NASA said Pathfinder's Ares Vallis landing site holds clues to a warmer, wetter Martian past, showing a floodplain covered with a variety of rock types, boulders, rounded and semi-rounded cobbles and pebbles. These rocks and pebbles are thought to have been swept down and deposited by floods which occurred early in Mars' evolution in the Ares and Tiu regions.

During its three months of operations, the mission was able to return about 2.6 gigabits of data, including over 16,000 images of the Martian surface from the lander camera, 550 images from the rover and about 8.5 million temperature, pressure and wind measurements.

In 2007, NASA's Mars Reconnaissance Orbiter (MRO) took an image of Pathfinder's landing site using its High Resolution Imaging Science Experiment. NASA said the lander's ramps, science deck and portions of the airbags can be seen in the images. The parachute and backshell used in the spacecraft's descent can be seen in the south, along with portions of the heat shield.

"Pathfinder's landing site is one of the most-studied places on Mars. Making connections between this new orbital image and the geological information collected at ground level aids our interpretation of orbital images of other places," Dr. Alfred McEwen of the University of Arizona, Tucson, principal investigator for the High Resolution Imaging Science Experiment said in 2007 when the image was released.