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2005 Mars Reconnaissance Orbiter:
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Aerobraking. With the spacecraft in orbit above Mars, the navigation team was able to start a six-month process of changing the initial 35-hour highly-elliptical orbit to a close-in more-circular orbit that would require only two hours for MRO to circle the planet.
That technique for changing the spacecraft's orbit is known as aerobraking. Flight controllers back on Earth are sending MRO on a series of shallow dips in the top of the Martian atmosphere. The atmospheric drag on the spacecraft slows it down slightly and change its orbit. Gradually, the spacecraft adjusts the shape of its orbit by using friction from those carefully calculated dips into the top of the Martian atmosphere.
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The powerful MRO science spacecraft carries six research instruments in the search for water and future sample-return landing sites on the surface. Among its tools is the most powerful telescope camera ever flown to another planet. The high-resolution camera will be able to see features on the planet as small as a few feet in diameter.
MRO will function as both weather satellite and geology explorer. A radar system known as SHARAD, supplied by the Italian Space Agency, will see a third of a mile below the planet's surface for signs of water ice. For instance, it might see permafrost extending deep into the planet. Scientists have wondered if water that once may have been in Mars' atmosphere might now be frozen underground.
MRO will start its scientific research in November 2006. During its first two years over the Red Planet, MRO will add to human knowledge of the history of ice on Mars.
From its orbit above the Red Planet, the Martian satellite will record extraordinarily-sharp images of thousands of rocks and other objects on the Martian landscapes about the size of a beach ball. That's a resolution of eight to twelve inches.
MRO has the largest and most powerful telescopic camera ever sent to another planet.
Mars today is cold and dry with frozen water caps covering its poles. Eons ago, it may have been wet and warm. That might have fostered life there.
MRO also is on the lookout for places where robot explorers could land on Mars. The probe's primary mission ends in 2010, but it may have enough fuel to work until 2014.
NASA will launch Phoenix Mars Scout in 2007 to look for organic chemicals, and Mars Science Laboratory in 2009.
High speed data transmission. For the second phase of its mission, MRO will work as a communications relay between Earth and other robot explorers on Mars.
Mars Reconnaissance Orbiter has the largest communications antenna ever carried to Mars. The spacecraft can transmit ten times as much data per minute as any previous Mars spacecraft.
MRO already has transmitted information at a rate of 6 megabits of data per second. At that speed, it could fill a CD-ROM in about a quarter-hour.
MRO is expected to return several times more data about the Red Planet than all previous Mars missions combined, according to NASA's Jet Propulsion Laboratory (JPL) at Pasadena California.
That data will include detailed observations of the Martian surface, subsurface and atmosphere by the instruments on the orbiter and enable data relay from other landers on the Martian surface to Earth.
Scientists back home on Earth will use the data to study the history and distribution of Martian water. Learning more about what has happened to the water will assist the ongoing search for possible past or present Martian life.
Observations by MRO also will help future Mars missions by finding and examining potential landing sites and providing a communications relay between the Martian surface and Earth.
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MRO joined a trio of spacecraft currently orbiting around Mars – Mars Express, Mars Odyssey, and Mars Global Surveyor.
The two-ton MRO carries some of the most sophisticated science instruments ever flown in space, including a telescopic camera that will record the sharpest images yet of the planet's surface.
Search for water. The orbiter is seeking evidence of water on the surface and sites where future robot explorers can land. It also acts as a communications relay for data headed to Earth.
The mission is analyzing the surface at new scales to follow hints of water detected in images from the Mars Global Surveyor spacecraft, and to bridge the gap between surface observations and measurements from orbit.
The spacecraft's scientific objectives include:
- researching present and past climate changes on Mars
- searching the surface and shallow-subsurface Martian landscape for evidence of water-related activity
- investigating the ubiquitous layers that have been observed on Mars
- probing the shallow-subsurface to identify regions where three-dimensional layering could indicate the presence of ice or possibly liquid water
- An ultra-high resolution, multi-color, stereo imaging system to return pictures of the Martian surface at six times higher resolution than previous images. It should improve understanding of surface processes related to water and to help identify future landing sites for sample-return missions and human exploration missions.
- A spectrometer for mapping minerals to provide extremely high-resolution hyperspectral images of areas on Mars in visible light to short-wave infrared (wavelengths from 0.4 to 4.0 micrometers). That helps researchers identify key mineral indicators of water and hydrothermal systems at scales even smaller than a football field. That data will be vital for targeting future landing missions.
- Italian Space Agency Sharad shallow-subsurface sounding radar
- gravity measurements
- accelerometer science
Other instruments aboard the Mars Reconnaissance Orbiter are experiments flying again after the loss of the Mars Climate Orbiter mission. In fact, MRO follows clues in hopes of finding where previously lost landers – the U.S. Mars Polar Lander and the U.K. Beagle 2 – might be.
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Launch of the MRO had been scrubbed on August 10 and 11. It took off at the scheduled moment on August 12.
For trips from Earth to Mars, the planets move into good position relative to each other for only a short period every 26 months.
The best launch position, which MRO used, is when Earth is about to overtake Mars in their concentric orbit "racing lanes" around the Sun.
Falling into orbit. As it approached the Red Planet, MRO fired its engines to slow down so it could be captured by the planet's gravity.
- At 2050 UTC (3:50 p.m. ET) on March 10, the orbiter pressurized its fuel in preparation for igniting its six main thrusters.
- At 2124 UTC (4:24 p.m. ET) the thruster burn started.
- The thrusters fired for 27 minutes.
- At 20 minutes into the burn, MRO disappeared, as planned, from Earth's view as it traveled behind Mars and out of radio contact with mission control in California.
- Controllers listened for a radio signal at the time when it had been predicted MRO would fly back into view as it traveled around the planet.
- When that radio signal was received, controllers knew MRO had successfully dropped into orbit around Mars.
- The navigation team at mission control was able to confirm the craft was in orbit half an hour after the signal was received.
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Team approach. The 2005 Mars Reconnaissance Orbiter spacecraft is an integrated scientific-observation platform that brought together teams from universities, industry, NASA centers and other organizations. It was built by Lockheed-Martin Astronautics, Denver.
Mars Reconnaissance Orbiter mission is managed by JPL, a division of the California Institute of Technology, for the NASA Science Mission Directorate at Washington, D.C. Lockheed Martin Space Systems, Denver, built the spacecraft and was prime contractor for the project.
NASA's Launch Services Program at the Kennedy Space Center (KSC) in Florida integrated and launched the spacecraft on the the Atlas-5 rocket. Atlas-5 combines a first stage, Russian-built, RD-81 rocket engine with a NASA-designed Centaur upper stage. MRO was the first government launch of a Lockheed Martin's Atlas-5 space rocket.
NASA has described the mission as an essential "scientific gateway" to the future of landing and sample-return missions at the heart of its Mars exploration program.
NASA's Mars Reconnaissance Orbiter home page »
