Mars Exploration Rovers (2003- )

Spacecraft exploration of Mars began in 1964 with Mariner 4. Previous attempts by both the USSR and United States to send a spacecraft to Mars had failed. Mariner 4 reached the red planet on July 15, 1964 and returned photographs and atmospheric measurements. Three more Mariner spacecraft, Mariner 6,7 and 9, successfully orbited Mars by the end of 1971.

Mariner Mission Information and Images

The Viking Mission consisted of two orbiting spacecraft, each carrying a lander that was deployed to the surface of Mars. Viking was the first mission to successfully land and operate from the surface of Mars. See The Viking Mission for details of the mission experiments and image data.

The Mars Pathfinder spacecraft landed on the surface of Mars on July 4, 1997. The Lander camera and instruments returned data on the Mars atmosphere and surrounding terrain in an ancient floodplain in the Ares Vallis region. The rover Sojourner became the first micro-rover to operate on another planet, analyzing rocks and soils and testing new rover technology for use in future planetary exploration.

More Information:
Mars Pathfinder website: http://marsprogram.jpl.nasa.gov/MPF/

The Mars Global Surveyor spacecraft entered Mars orbit in September of 1997. The spacecraft began high-resolution mapping of the Mars surface in March of 1999. The spacecraft gathered data on the planet's topographic, thermal, mineral and magnetic properties. After studying Mars four times as long as originally planned, Mars Global Surveyor orbiter succumbed to battery failure in 2006.

More information:
Mars Global Surveyor website: http://marsprogram.jpl.nasa.gov/mgs/

The 2001 Mars Odyssey is an orbiter spacecraft that was launched to Mars April 7, 2001 and arrived in October, 2001. The Orbiter carries 3 science instruments: The Thermal Emission Imaging System (THEMIS) designed to map mineralogy and morphology or the Martian surface, The Gamma Ray Spectrometer (GRS) used for global mapping of the elemental composition of the surface to determine the abundance of hydrogen in the shallow subsurface, and the Mars Radiation Environment Experiment (MARIE) which examines the near-space radiation environment to assess radiation-related risks to human explorers.

More information:
Mars Odyssey website: http://mars.jpl.nasa.gov/odyssey/

The European Space Agency with cooperation from NASA and the Italian Space Agency launched the Mars Express spacecraft in 2003 to explore the atmosphere and surface of Mars from polar orbit. The mission objective is to search for sub-surface water from orbit. A small lander named Beagle, was sent to the surface, but communications were lost. The spacecraft carries seven scientific instruments, including some similar to the European instruments lost on the ill-fated Russian Mars '96 mission.

More information:
Mars Express website: http://www.esa.int/marsexpress

In 2003, two large rovers called Spirit and Opportunity were launched to Mars to explore the Martian surface in much the same way that the Mars Pathfinder Sojourner rover did in 1997. However, these rovers have greater maneuverability and range, traveling up to 100 meters (about 110 yards) across the surface in a Martian day. Each rover carries instruments designed to search for evidence of liquid water that may have been present in the planet's past. Spirit's mission was to explore Gusev Crater which may hold ancient lake deposits, and Opportunity's site is Meridiani Planum which contains a large deposit of hematite, an iron mineral. In March 2004, Opportunity discovered a rock with cross-bedding, a sedimentary structure formed by flowing water. This, combined with chemical data, indicates that the rock formed in a shallow, salty body of surface water.

The Mars Reconnaissance Orbiter launched in 2005. Two of the spacecraft's instruments include HiRISE, a high resolution imager, and SHARAD, a shallow subsurface sounding radar. HiRISE is studying the layering and structure of the martian surface. SHARAD is mapping subsurface geologic deposits and searching for buried water ice.

Scientists from the National Air and Space Museum's Center for Earth and Planetary Studies have been selected as science team members for this mission. Dr. John Grant is a co-investigator on HiRISE and Dr. Bruce Campbell is a member of the science team for SHARAD.

Discoveries and data from Mars Reconnaissance Orbiter, Mars Exploration Rovers and Mars Express are displayed in the Mars section of the Exploring The Planets gallery, updated in 2010.

More Information:
Mars Reconnaissance Orbiter website: http://www.nasa.gov/MRO/

Mars Science Laboratory (MSL)

The Mars Science Laboratory (MSL) mission continues NASA's Mars Exploration Program following the Mars Exploration Rovers, Mars Reconnaissance Orbiter, and Phoenix missions. The mission is sending "Curiosity" Rover to explore the surface of Mars. Center for Earth and Planetary scientist John Grant co-chaired the MSL Mars Landing Site Steering Committee. Read more about Gale Crater, the landing site selected for the Mars Science Laboratory.
More information:
NASA Mars Science Laboratory website
Follow @MarsCuriosity on Twitter

Find out more about future missions to Mars at http://www.nasa.gov/mars