Model of Mars Reconnaissance Orbiter A half-scale model of Mars Reconnaissance Orbiter shows the high-gain antenna at the top. To the sides are the solar panels; below the antenna are the scientific instruments. Image credit: NASA/JPL Link to Full Res

The Mars Reconnaissance Orbiter is the first of its kind, with a unique payload to accomplish an ambitious set of goals. It is being developed at a cost of $500 million for the spacecraft, all the on-board equipment, and the Atlas V rocket that will launch it into space.

After reaching Mars, the orbiter will study the red planet using a fully equipped scientific laboratory of instruments designed in several states and one foreign country, including California, Arizona, Colorado, Maryland, and Italy.

Together, the instruments will return up to 40 times more data to Earth than any previous Mars mission.

	Phoenix lander The Mars Reconnaissance Orbiter will pursue NASA's strategy to "follow the water" and help pave the way for future missions to Mars. One of those missions is the Phoenix lander, pictured here. Image credit: NASA/JPL Link to Full Res

One of a Series of Spacecraft

Each of the scientific experiments will build on information from earlier missions to Mars and pave the way for future missions. They?re all part of NASA?s strategy to ?follow the water? to look for signs of present or past life on Mars, understand its climate and geologic history, and provide data that supports eventual human exploration.

Just as earlier Mars orbiters helped scientists and engineers select the two landing sites now being explored by the NASA rovers Spirit and Opportunity, the Mars Reconnaissance Orbiter will help researchers select landing sites for future missions. One of these is the Phoenix lander, scheduled for launch in August 2007. Another is the Mars Science Laboratory, the next robotic rover planned for launch in October 2009.

Water features on Mars Orbital images of gullies emerging from layered outcrops, meandering channels, and fan-shaped aprons of debris on Mars are evidence of erosion involving a fluid, such as water, running downslope. This image was taken by the Mars Orbiter Camera on board the Mars Global Surveyer. Image credit: NASA/JPL/Malin Space Science Systems Link to Full Res

Evidence of Water on Mars

In 1998, NASA's Mars Global Surveyor identified hematite, an iron mineral that can form in the presence of water, at the Opportunity landing site. An infrared spectrometer detected a substantial deposit of gray hematite in a 500-kilometer-wide region called Sinus Meridiani, where Opportunity landed. Hematite is known to form in the presence of water.

Halfway around the planet, imaging data indicating that water may once have flowed into and through Gusev Crater drove the selection of the Spirit landing site.

After entering orbit around Mars in 2006, the Mars Reconnaissance Orbiter will provide detailed images, mineral composition maps, subsurface radar profiles, and atmospheric data to help Phoenix mission planners make their final selection from a handful of sites near the north pole of Mars.

	Cross-laminae in martian rock NASA's Mars Exploration Rover Opportunity discovered fine layers of rock that dip toward each other, known as cross lamination. These features were likely formed when flowing water formed ripples in underwater sediment and then pushed the ripples downstream. Image credit: NASA/JPL/Cornell/USGS Link to Full Res

Water-related Minerals

The Opportunity site was somewhat exceptional in that it was the only region in which a water-related mineral exposed at the surface had clearly been identified. More recently, the Mars Express, a European Space Agency orbiter, discovered kieserite, a water-bearing mineral that also contains magnesium and sulfur. The kieserite was found in patches of Valles Marineris, a huge canyon whose length from end to end is comparable to the distance from New York to Los Angeles.

Valles Marineris Valles Marineris, the largest canyon in the solar system, is one of several sites where researchers may send future rovers to Mars. The Mars Reconnaissance Orbiter will collect the detailed data needed to help pave the way. This northward-looking view is a composite of images from the Viking orbiter. Image credit: NASA/JPL Link to Full Res

Search for Future Landing Sites

Mars Reconnaissance Orbiter will survey the entire planet at the same higher resolution (level of detail) as that used by Mars Express, and will be able to zoom in even closer on special features. It will be able to determine the composition of surface features as small as 30 feet across, the size of Eagle Crater, where Opportunity landed. This new, more detailed data will help scientists and engineers search for the best landing sites. One such site is Valles Marineris, which is likely to be suggested as a potential destination for the Mars Science Laboratory, according to Gentry Lee, chief engineer of the Planetary Flight Projects Directorate at JPL.