Thirty years after the first successful landing on Mars by NASA's Viking spacecraft, the ambitious mission continues to evoke pride and enthusiasm for future space exploration.

NASA's Viking 1 and 2 missions to Mars, each consisting of an orbiter and a lander, became the first space probes to obtain high resolution images of the Martian surface, characterize the structure and composition of the atmosphere and surface, and conduct on-the-spot biological tests for life on another planet.

Viking 1 was launched August 20, 1975, and arrived at Mars June 19, 1976. On July 20, 1976, the Viking 1 lander separated from the orbiter and touched down at Chryse Planitia. Viking 2 was launched September 9, 1975, and entered Mars orbit August 7, 1976. The Viking 2 lander touched down at Utopia Planitia September 3, 1976.

"The Viking team didn't know the Martian atmosphere very well, we had almost no idea about the terrain or the rocks, and yet we had the temerity to try to soft land on the surface," recalled Gentry Lee, Solar System Exploration chief engineer at NASA's Jet Propulsion Laboratory, Pasadena, Calif. "We were both terrified and exhilarated. All of us exploded with joy and pride when we saw that we had indeed landed safely."

"The Viking mission looms like a legendary giant, an incredible success against which all present and future missions will be measured," said Doug McCuiston, Mars Exploration Program director at NASA Headquarters in Washington.

Originally designed to function for 90 days, the Viking spacecraft continued collecting data for more than six years. The landers accumulated 4,500 up-close images of the Martian surface. The accompanying orbiters provided more than 50,000 images, mapping 97 percent of the planet. Measurements of the atmosphere and surface of Mars obtained by the orbiters and landers are still being analyzed and interpreted.

Viking provided the first measurements of the atmosphere and surface of Mars. The data suggested early Mars was very different from the present day planet. Viking performed the first successful entry, descent and landing on Mars. Derivations of a Viking-style thermal protection system and parachute have been used on every U.S. Mars lander mission, including Mars Pathfinder and the Mars Exploration Rovers, Spirit and Opportunity.

NASA's Langley Research Center, Hampton, Va., managed the Viking Program. The Jet Propulsion Laboratory built the orbiters, provided the deep space network and managed the science mission. NASA's Glenn Research Center, Cleveland, designed the Atlas/Centaur rockets that propelled the spacecraft on their journey. NASA's Kennedy Space Center, Fla., provided the launch facility for the program. Scientists from across NASA served on the Viking science teams.

For more information about Viking, visit:

http://www.nasa.gov/viking

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