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NASA
The Mars Surveyor Program
Born as a result of the failure of Mars Observer (MO), the Mars Surveyor Program was designed to explore Mars with all the original measurements planned for MO, and a lot more. It varied from the MO mission in that the Surveyor Program would use vastly cheaper spacecraft, and newer, more experimental engineering and design. Among the questions the Mars Surveyor Program was designed to address was where is the Martian water?The program was suppose to consist of spacecraft to be launched about every 26 months. The launchings were designed to take advantage of periods when the Earth and Mars were closest together.
The spacecraft were named: Mars Pathfinder, Mars Global Surveyor, Mars '98, Mars 2001, Mars 2003, and Mars 2005. The Pathfinder mission was a huge success. And the Mars Global Surveyor is still taking measurements. However, the Mars '98 Orbiter and Lander were lost. After this great disappointment, NASA saw a need to rethink Mars exploration. This concluded the Mars Surveyor Program.
In 2000, a new Mars Exploration Program was announced. This new program includes the Mars Odyssey 2001 mission which was launched in April 2001. It also provides for five other major Mars missions in the next decade. NASA plans to launch twin rovers which will land on Mars in 2003 and a powerful scientific orbiter to be launched in 2005. A mobile science laboratory and the first of several smaller Scout missions are planned for 2007. Wrapping up this phase of exploration would be a sample return mission possibly as early as 2011.