Category: Mars

Image showing the heat being emitted from the day and night side of Mars. Image credit: NASA Click to enlarge
Now firmly in orbit around the Red Planet, NASA’s Mars Reconnaissance Orbiter has begun a series of maneuvers through the atmosphere to slow itself down even further. The process is called aerobraking, and each successive pass slows it down a little bit, lowering its orbit. After 6 months of aerobraking, sweeping through the atmosphere 550 times, the spacecraft will be in its final science orbit.

NASA’s Mars Reconnaissance Orbiter yesterday began a crucial six-month campaign to gradually shrink its orbit into the best geometry for the mission’s science work.

Three weeks after successfully entering orbit around Mars, the spacecraft is in a phase called “aerobraking.” This process uses friction with the tenuous upper atmosphere to transform a very elongated 35-hour orbit to the nearly circular two-hour orbit needed for the mission’s science observations.

The orbiter has been flying about 426 kilometers (265 miles) above Mars’ surface at the nearest point of each loop since March 10, then swinging more than 43,000 kilometers (27,000 miles) away before heading in again. While preparing for aerobraking, the flight team tested several instruments, obtaining the orbiter’s first Mars pictures and demonstrating the ability of its Mars Climate Sounder instrument to track the atmosphere’s dust, water vapor and temperatures.

On Thursday, Mars Reconnaissance Orbiter fired its intermediate thrusters for 58 seconds at the far point of the orbit. That maneuver lowered its altitude to 333 kilometers (207 miles) when the spacecraft next passed the near point of its orbit, at 6:46 a.m. Pacific time today (9:46 a.m. Eastern Time).

“We’re not low enough to touch Mars’ atmosphere yet, but we’ll get to that point next week,” said Dr. Daniel Kubitschek of NASA’s Jet Propulsion Laboratory, Pasadena, Calif., deputy leader for the aerobraking phase of the mission.

The phase includes about 550 dips into the atmosphere, each carefully planned for the desired amount of braking. At first, the dips will be more than 30 hours apart. By August, there will be four per day.

“We have to be sure we don’t dive too deep, because that could overheat parts of the orbiter,” Kubitschek said. “The biggest challenge is the variability of the atmosphere.”

Readings from accelerometers during the passes through the atmosphere are one way the spacecraft can provide information about upward swelling of the atmosphere due to heating.

The Mars Climate Sounder instrument also has the capability to monitor changes in temperature that would affect the atmosphere’s thickness. “We demonstrated that we’re ready to support aerobraking, should we be needed,” JPL’s Dr. Daniel McCleese, principal investigator for the Mars Climate Sounder, said of new test observations.

Infrared-sensing instruments and cameras on two other Mars orbiters are expected to be the main sources of information to the advisory team of atmospheric scientists providing day-to-day assistance to the aerobraking navigators and engineers. “There is risk every time we enter the atmosphere, and we are fortunate to have Mars Global Surveyor and Mars Odyssey with their daily global coverage helping us watch for changes that could increase the risk,” said JPL’s Jim Graf, project manager for the Mars Reconnaissance Orbiter.

Using aerobraking to get the spacecraft’s orbit to the desired shape, instead of doing the whole job with thruster firings, reduces how much fuel a spacecraft needs to carry when launched from Earth. “It allows you to fly more science payload to Mars instead of more fuel,” Kubitschek said.

Once in its science orbit, Mars Reconnaissance Orbiter will return more data about the planet than all previous Mars missions combined. The data will help researchers decipher the processes of change on the planet. It will also aid future missions to the surface of Mars by examining potential landing sites and providing a high-data-rate communications relay.

Test observations from the Mars Climate Sounder, other images and additional information about Mars Reconnaissance Orbiter are available online at http://www.nasa.gov/mro and at http://marsprogram.jpl.nasa.gov/mro .

For information about NASA and agency programs on the Web, visit http://www.nasa.gov .

Original Source: NASA News Release

ESA’s Mars Express took this photograph of Libya Montes, which is south of the large Isidis Planitia impact basin on Mars. The region contains a 400 km (248 mile) long valley that was carved into the early Martian surface; probably by water when the planet was warm and wet. Scientists estimate that the same amount of water was probably flowing out of the region as middle reaches of the Mississippi river in the US.

These images, taken by the High Resolution Stereo Camera (HRSC) on board ESA’s Mars Express spacecraft, show the region of Libya Montes, south of the Isidis Planitia impact basin on Mars.

The HRSC obtained these images during orbit 922 with a ground resolution of approximately 14.3 metres per pixel at equatorial latitudes near longitude 81 degrees East.

The images show the central reaches of a 400-kilometre long valley that was carved into the surface in early Martian history, approximately 3500 million years ago.

The central parts of the broad valley show traces of an interior valley, documenting the flow of water that once occurred on the surface of the planet during periods of wetter climate.

Determinations of discharge volumes on the basis of high-resolution HRSC derived digital terrain models reveal discharge rates that are comparable to those of the middle reaches of the Mississippi river in the USA.

On the basis of crater-size frequency distributions on the valley floor and surrounding terrain it has been shown that the formation time of the valley amounts to approximately 350 million years.

Measurements of erosion rates suggest that the active phases of valley development are characterised by short periods of intense fluvial activity rather than sustained liquid flow.

Details on valley formation have been published by R. Jaumann (DLR) and colleagues, as an article ‘Constraints on fluvial erosion by measurements of the Mars Express High Resolution Stereo Camera’ in Geophysical Research Letters, 32, L16203, doi:10.1029/2005GL023415).

***image4:right***The colour scenes were derived from the three HRSC colour channels and the nadir channel. The perspective views have been calculated from the digital terrain model derived from the stereo channels.

The 3D anaglyph image was calculated from the nadir and one stereo channel. The black and white high-resolution images were derived from the nadir channel that provides the highest detail of all the channels.

Original Source: ESA Mars Express

A portion of the first full-resolution image returned by MRO. Image credit: NASA/JPL. Click to enlarge.
After years of development and months of spaceflight, NASA’s Mars Reconnaissance Orbiter is beginning to return photos of the Red Planet. The spacecraft pointed three of its cameras at the surface of Mars on Thursday, and started snapping pictures. This photo was taken when the spacecraft was at an altitude of 2,489 kilometers (1,547 miles), which is about 9 times as high as its final orbit – the pictures are going to just get better. Even so, the resolution at this altitude is about the same as the best pictures returned by other Mars orbiters.

The first test images of Mars from NASA’s newest spacecraft provide a tantalizing preview of what the orbiter will reveal when its main science mission begins next fall.

Three cameras on NASA’s Mars Reconnaissance Orbiter were pointed at Mars at 8:36 p.m. PST Thursday, while the spacecraft collected 40 minutes of engineering test data. The cameras are the High Resolution Imaging Science Experiment, the Context Camera and the Mars Color Imager.

“These high-resolution images of Mars are thrilling, and unique given the early morning time-of-day. The final orbit of Mars Reconnaissance Orbiter will be over Mars in the mid-afternoon, like Mars Global Surveyor and Mars Odyssey,” said Alfred McEwen, University of Arizona, Tucson, principal investigator for the orbiter’s High Resolution Imaging Science Experiment camera.

“These images provide the first opportunity to test camera settings and the spacecraft’s ability to point the camera with Mars filling the instruments’ field of view,” said Steve Saunders, the mission’s program scientist at NASA Headquarters. “The information learned will be used to prepare for the primary mission next fall.” The main purpose of these images is to enable the camera team to develop calibration and image-processing procedures such as the precise corrections needed for color imaging and for high-resolution surface measurements from stereo pairs of images.

To get desired groundspeeds and lighting conditions for the test images, researchers programmed the cameras to shoot while the spacecraft was flying about 2,489 kilometers (1,547 miles) or more above Mars’ surface, about nine times the range planned for the orbiter’s primary science mission. Even so, the highest resolution of about 2.5 meters (8 feet) per pixel – an object 8 feet in diameter would appear as a dot — is comparable to some of the best resolution previously achieved from Mars orbit.

Further processing of the images during the next week or two is expected to combine narrow swaths into broader views and show color in some portions.

The Mars Reconnaissance Orbiter has been flying in elongated orbits around Mars since it entered orbit on March 10. Every 35 hours, it has swung about 44,000 kilometers (27,000 miles) away from the planet then come back within about 425 kilometers (264 miles) of Mars’ surface.

Mission operations teams at NASA’s Jet Propulsion Laboratory, Pasadena, Calif, and at Lockheed Martin Space Systems, Denver, continue preparing for aerobraking. That process will use about 550 careful dips into the atmosphere during the next seven months to shrink the orbit to a near-circular shape less than 300 kilometers (200 miles) above the ground.

More than 25 gigabits of imaging data, enough to nearly fill five CD-ROMs, were received through NASA’s Deep Space Network station at Canberra, Australia, and sent to JPL. They were made available to the camera teams at the University of Arizona Lunar and Planetary Laboratory and Malin Space Science Systems, San Diego, Calif.

Preliminary images from the High Resolution Imaging Science Experiment and additional information about the Mars Reconnaissance Orbiter are available online at: http://www.nasa.gov/mro or http://HiRISE.lpl.arizona.edu

Additional processing has begun for release of other images from the test in coming days.

For information about NASA and agency programs on the Web, visit: http://www.nasa.gov

JPL, a division of the California Institute of Technology in Pasadena, manages the Mars Reconnaissance Orbiter for NASA’s Science Mission Directorate, Washington. Lockheed Martin Space Systems is the prime contractor for the project and built the spacecraft.

Original Source: NASA/JPL News Release

This photograph was taken by ESA’s Mars Express spacecraft. It shows a mountain in the eastern Hellas Planitia region with craters partly filled with debris. It’s possible that the mountain was covered by glaciers in the past, which filled up the craters with ice and debris; the debris remained after the glaciers retreated. The craters are largely free of meteorite impacts inside, so it’s believed they filled with debris less than a few million years ago.

This video and accompanying images, taken by the High Resolution Stereo Camera (HRSC) on board ESA’s Mars Express spacecraft, show an unusual flow deposit on the floors of two adjacent impact craters in the eastern Hellas Planitia region, indicating possible glacial processes.

The stereo capability of the HRSC makes it possible to animate 3D anaglyph images, based on digital elevation models. The image data have been acquired during Mars Express orbit 451 from an altitude of 590 kilometres with an original resolution of 29 metres per pixel.

The unusual ‘hourglass’-shaped structure is located in the southern-hemisphere highland terrain of Promethei Terra at the eastern rim of the Hellas Basin, at about latitude 38 South and longitude 104 East.

Most likely the surface morphology is formed by the ‘creep’ of ice and debris, similar to either terrestrial rock glacier landforms or debris covered glaciers which are commonly found in high latitudes and alpine regions.

‘Talus’ material (or ‘scree’, the broken rocks that lie on a steep mountainside or at the base of a cliff) and ice-rich debris accumulated at the base of the remnant massif and filled the upper bowl-shaped impact crater which is approximately nine kilometres wide. The debris-ice mixture then flowed through a breach in the crater rim into a 17-kilometre wide crater, 500 metres below, taking advantage of the downward slope.***image4:left***

Of particular interest is the age of these surfaces, which seem to be fairly intact over a wide area. It has been shown recently that there is some evidence that glaciers were shaping the Martian surface at mid latitudes and even near the equator until a few million years ago.

Typical evidence for a significant loss of volatiles, such as pits and other depressions can be observed on all debris surfaces surrounding the remnant massif.

The statistical analysis of the number of craters formed by meteorite impacts used for age determination also shows that part of the surface with its present-day glacial characteristics was formed only a few million years ago.

Original Source: Mars Express

Mars gullies in Noachis Terra region. Image credit: NASA Click to enlarge
It was only a few years that researchers announced the discovery of gullies on Mars. Here on Earth, gullies like this are formed when water flows quickly down a hill, and erodes the soil. Unfortunately, there might be another explanation for the Martian version – since similar gullies have now been seen on the Moon as well. It’s possible that the gullies are formed completely dry, when micrometeorites strike the side of a crater wall and trigger a landslide.

If you’re a scientist studying the surface of Mars, few discoveries could be more exciting than seeing recent gullies apparently formed by running water.

And that’s what scientists believed they saw in Mars Orbital Camera (MOC) images five years ago. They published a paper in Science on MOC images that show small, geologically young ravines. They concluded that the gullies are evidence that liquid water flowed on Mars’ surface sometime within the last million years.

A word of caution, though: The moon has gullies that look like that, a University of Arizona Lunar and Planetary Laboratory researcher has found. And water certainly didn’t form gullies on the waterless moon.

Gwendolyn D. Bart is presenting the work today at the 37th Lunar and Planetary Science Conference in Houston.

“We’d all like to find liquid water on Mars,” Bart said. “That would be really, really exciting. If there were liquid water on Mars, humans wouldn’t have to ship water from Earth when they go to explore the planet. That would be an enormous cost savings. And liquid water near the surface of Mars would greatly increase the chances for native life on Mars.”

The 2000 Science paper was provocative, Bart said. “But I was skeptical. I wondered if there is another explanation for the gullies.”

Then last year she heard a talk by Allan Treiman of the Lunar and Planetary Institute. Treiman suggested the martian gullies might be dry landslides, perhaps formed by wind and not formed by water at all.

Recently, Bart was studying the lunar landscape in high-resolution images taken in 1969, prior to the Apollo landings, for her research on processes that modify the lunar surface.

“Totally by accident, I saw gullies that looked strikingly like the gullies on Mars,” she said.

“If the dry landslide hypothesis for the formation of martian gullies is correct, we might expect to see similar features on the moon, where there is no water,” she said. “We do.”

Gullies in the moon’s 10-mile-diameter (17 kilometer) crater Dawes are similar in structure and size to those in a martian crater that MOC photographed. Micrometeorites hitting the smooth slopes and crater on the airless moon could easily trigger small avalanches that form gullies, Bart said.

However, the martian gullies also resemble gullies on Earth that were formed by water, she noted.

“My point is that you can’t just look at the Mars gullies and assume they were formed by water. It may be, or may be not. We need another test to know.”

Original Source: UA News Release

Artist’s concept of MRO in orbit at Mars. Image credit: NASA/JPL Click to enlarge
Data transmitted back to Earth by NASA’s Mars Reconnaissance Orbiter indicates that the spacecraft successfully inserted itself into orbit around the Red Planet. It fired its main thrusters long enough to slow down its speed so Mars could capture it a wide orbit. The spacecraft will spend the next half-year aerobraking to lower down into a nearly circular orbit. Its instruments will be capable of resolving the Martian surface better than any spacecraft currently orbiting Mars.

With a crucially timed firing of its main engines today, NASA’s new mission to Mars successfully put itself into orbit around the red planet.

The spacecraft, Mars Reconnaissance Orbiter, will provide more science data than all previous Mars missions combined.

Signals received from the spacecraft at 2:16 p.m. Pacific Time after it emerged from its first pass behind Mars set off cheers and applause in control rooms at NASA’s Jet Propulsion Laboratory, Pasadena, Calif., and at Lockheed Martin Space Systems, Denver.

“This is a great milestone to have accomplished, but it’s just one of many milestones before we can open the champagne,” said Colleen Hartman, deputy associate administrator for NASA’s Science Mission Directorate. “Once we are in the prime science orbit, the spacecraft will perform observations of the atmosphere, surface, and subsurface of Mars in unprecedented detail.”

The spacecraft traveled about 500 million kilometers (310 million miles) to reach Mars after its launch from Florida on Aug. 12, 2005. It needed to use its main thrusters as it neared the planet in order to slow itself enough for Mars’ gravity to capture it. The thruster firing began while the spacecraft was still in radio contact with Earth, but needed to end during a tense half hour of radio silence while the spacecraft flew behind Mars.

“Our spacecraft has finally become an orbiter,” said JPL’s Jim Graf, project manager for the mission. “The celebration feels great, but it will be very brief because before we start our main science phase, we still have six months of challenging work to adjust the orbit to the right size and shape.”

For the next half-year, the mission will use hundreds of carefully calculated dips into Mars’ atmosphere in a process called “aerobraking.” This will shrink its orbit from the elongated ellipse it is now flying, to a nearly circular two-hour orbit. For the mission’s principal science phase, scheduled to begin in November, the desired orbit is a nearly circular loop ranging from 320 kilometers (199 miles) to 255 kilometers (158 miles) in altitude, lower than any previous Mars orbiter. To go directly into such an orbit instead of using aerobraking, the mission would have needed to carry about 70 percent more fuel when it launched.

The instruments on Mars Reconnaissance Orbiter will examine the planet from this low-altitude orbit. A spectrometer will map water-related minerals in patches as small as a baseball infield. A radar instrument will probe for underground layers of rock and water. One telescopic camera will resolve features as small as a card table. Another will put the highest-resolution images into broader context. A color camera will monitor the entire planet daily for changes in weather. A radiometer will check each layer of the atmosphere for variations in temperature, water vapor and dust.

“The missions currently at Mars have each advanced what we know about the presence and history of water on Mars, and one of the main goals for Mars Reconnaissance Orbiter is to decipher when water was on the surface and where it is now,” said JPL’s Dr. Richard Zurek, project scientist for the mission. “Water is essential for life, so that will help focus future studies of whether Mars has ever supported life.”

The orbiter can radio data to Earth at up to 10 times the rate of any previous Mars mission. Besides sending home the pictures and other information from its own investigations, it will relay data from surface missions, including NASA’s Phoenix Mars Scout scheduled for launch in 2007 and Mars Science Laboratory in development for 2009.

Additional information about Mars Reconnaissance Orbiter is available online at:

http://www.nasa.gov/mro

The mission is managed by JPL, a division of the California Institute of Technology, Pasadena, for the NASA Science Mission Directorate, Washington. Lockheed Martin Space Systems, Denver, is the prime contractor for the project and built the spacecraft.

Original Source: NASA News Release

Flight through Mariner Valley. Image credit: NASA/JPL. Click to enlarge.
NASA researchers have created a virtual fly through of Valles Marineris on Mars. This video was created by stitching together images taken by the Thermal Emission Imaging System multi-band camera on NASA’s Mars Odyssey spacecraft. The images showed details as small as 300 meters (1,000 feet) across, and were taken during in infrared during the Martian daytime. The final images were coloured on computer to approximate how the landscape would look to the human eye.

A new view of the biggest canyon in the solar system, merging hundreds of photos from NASA’s Mars Odyssey orbiter, offers scientists and the public an online resource for exploring the entire canyon in detail.

This canyon system on Mars, named Valles Marineris, stretches as far as the distance from California to New York. Steep walls nearly as high as Mount Everest give way to numerous side canyons, possibly carved by water. In places, walls have shed massive landslides spilling far out onto the canyon floor.

A simulated fly-through using the newly assembled imagery is available online. The fly-through plus tools for wandering across and zooming into the large image are also available.

“We picked Valles Marineris to make this first mosaic because it’s probably the most complex, interesting feature on the entire planet,” said Dr. Phil Christensen of Arizona State University, Tempe. He is the principal investigator for Mars Odyssey’s versatile camera, the Thermal Emission Imaging System. “To understand many of the processes on Mars — erosion, landsliding and the effects of water — you really need to have a big-picture view but still be able to see the details.”

Small parts of the canyon have been seen at higher resolution, but at 100 meters (328 feet) per pixel, the new view has sharper resolution than any previous imaging of the entire canyon.

In addition to the completed mosaic of Valles Marineris images, the camera team has also prepared an online data set of nearly the entire planet of Mars at 232 meters (760 feet) per pixel, the most detailed global view of the red planet. The team plans to post 100-meter-resolution mosaics of other regions of Mars in coming months.

Odyssey reached Mars in 2001. The Thermal Emission Imaging System began observing the planet systematically in February 2002 both in visible wavelengths and in infrared wavelengths, which are better for seeing surface details through Mars’ atmospheric dust. As the spacecraft passes over an area, the camera records images of swaths 32 kilometers wide (20 miles wide). More than three years of observations made at infrared wavelengths during Martian daytime are combined into the assembled view of Valles Marineris and the global image data set.

Mars Odyssey is managed by NASA’s Jet Propulsion Laboratory, a division of the California Institute of Technology, Pasadena, for NASA’s Science Mission Directorate, Washington. Lockheed Martin Space Systems, Denver, is the prime contractor for the project and built the spacecraft. The orbiter began an extended mission in August 2004 after successfully completing its primary mission.

Original Source: NASA/JPL News Release

NASA’s Mars orbiter approaching Mars. Image credit: NASA/JPL Click to enlarge
Mars added a new satellite today, when NASA’s Mars Reconnaissance Orbiter arrived at the Red Planet. The spacecraft fired its engines for 27 minutes shortly before arrival to slow it down a little, just enough so that Mars could capture it with its gravity. Over the next seven months, the spacecraft will pass through Mars’ atmosphere 550 times, slowing itself down further through a process called aerobraking. After having settled into its final orbit, it will search for signs of water and scout out future landing locations.

NASA’s Mars Reconnaissance Orbiter has begun its final approach to the red planet after activating a sequence of commands designed to get the spacecraft successfully into orbit.

The sequence began Tuesday and will culminate with firing the craft’s main thrusters for about 27 minutes on Friday — a foot on the brakes to reduce velocity by about 20 percent as the spacecraft swings around Mars at about 5,000 meters per second (about 11,000 miles per hour). Mission controllers at NASA’s Jet Propulsion Laboratory, Pasadena, Calif., and Lockheed Martin Space Systems, Denver, are monitoring the events closely.

“We have been preparing for years for the critical events the spacecraft must execute on Friday,” said JPL’s Jim Graf, project manager. “By all indications, we’re in great shape to succeed, but Mars has taught us never to get overconfident. Two of the last four orbiters NASA sent to Mars did not survive final approach.”

Mars Reconnaissance Orbiter will build upon discoveries by five successful robots currently active at Mars: NASA rovers Spirit and Opportunity, NASA orbiters Mars Global Surveyor and Mars Odyssey, and the European Space Agency’s Mars Express orbiter. It will examine Mars’ surface, atmosphere and underground layers in great detail from a low orbit. It will aid future missions by scouting possible landing sites and relaying communications. It will send home up to 10 times as much data per minute as any previous Mars mission.

First, it must get into orbit. The necessary thruster burn will begin shortly after 1:24 p.m. Pacific Time on Friday. Engineers designed the burn to slow the spacecraft just enough for Mars’ gravity to capture it into a very elongated elliptical orbit. A half-year period of more than 500 carefully calculated dips into Mars’ atmosphere — a process called aerobraking — will use friction with the atmosphere to gradually shrink the orbit to the size and nearly-circular shape chosen for most advantageous use of the six onboard science instruments.

“Our primary science phase won’t begin until November, but we’ll actually be studying the changeable structure of Mars’ atmosphere by sensing the density of the atmosphere at different altitudes each time we fly through it during aerobraking,” said JPL’s Dr. Richard Zurek, project scientist for the mission.

Additional information about Mars Reconnaissance Orbiter is available online at: http://www.nasa.gov/mro

The mission is managed by JPL, a division of the California Institute of Technology, Pasadena, for the NASA Science Mission Directorate, Washington. Lockheed Martin Space Systems, Denver, is the prime contractor for the project and built the spacecraft.

Original Source: NASA News Release

The eastern scarp of the Olympus Mons volcano. Image credit: ESA Click to enlarge
This photograph was taken by ESA’s Mars Express spacecraft. It shows the eastern edge of the Olympus Mons volcano on Mars – the biggest mountain the Solar System. These huge cliffs tower above the relatively flat eastern plains around the mountain. The region has been covered repeatedly by lava flows, as recently as 200 million years ago.

This image, taken by the High Resolution Stereo Camera (HRSC) on board ESA’s Mars Express spacecraft, shows the eastern scarp of the Olympus Mons volcano on Mars.

The HRSC obtained this images during orbit 1089 with a ground resolution of approximately 11 metres per pixel. The image is centred at 17.5 North and 230.5 East. The scarp is up to six kilometres high in places.

The surface of the summit plateau’s eastern flank shows lava flows that have are several kilometres long and a few hundred metres wide.

Age determinations show that they are up to 200 million years old, in some places even older, indicating episodic geological activity.

The lowland plains, seen here in the eastern part of the image (bottom), typically have a smooth surface.

Several channel-like features are visible which form a broad network composed of intersecting and ‘anastomosing’* channels that are several kilometres long and up to 40 metres deep. (*Anastomising means branching extensively and crossing over one another, like veins on the back of your hand.)

Several incisions suggest a tectonic control, others show streamlined islands and terraced walls suggesting outflow activity.

Age determinations show that the network-bearing area was geologically active as recent as 30 million years ago.

Between the edge of the lowland plains and the bottom of the volcano slope, there are ‘wrinkle ridges’ which are interpreted as the result of compressional deformation. In some places, wrinkle ridges border the arch-like terraces at the foot of the volcano slope.

The colour scenes have been derived from the three HRSC-colour channels and the nadir channel. The perspective views have been calculated from the digital terrain model derived from the stereo channels.

The 3D anaglyph image was calculated from the nadir and one stereo channel.

Original Source: ESA Portal

Artist’s concept of Mars Reconnaissance Orbiter approaching Mars. Image credit: NASA/JPL Click to enlarge
As it nears Mars on March 10, a NASA spacecraft designed to examine the red planet in unprecedented detail from low orbit will point its main thrusters forward, then fire them to slow itself enough for Mars’ gravity to grab it into orbit.

Ground controllers for Mars Reconnaissance Orbiter expect a signal shortly after 1:24 p.m. Pacific time (4:24 p.m. Eastern time) that this mission-critical engine burn has begun. However, the burn will end during a suspenseful half hour with the spacecraft behind Mars and out of radio contact.

“This mission will greatly expand our scientific understanding of Mars, pave the way for our next robotic missions later in this decade, and help us prepare for sending humans to Mars,” said Doug McCuistion, Director of NASA’s Mars Exploration Program. “Not only will Mars Science Laboratory’s landing and research areas be determined by the Mars Reconnaissance Orbiter, but the first boots on Mars will probably get dusty at one of the many potential landing sites this orbiter will inspect all over the planet.”

The orbiter carries six instruments for studying every level of Mars from underground layers to the top of the atmosphere. Among them, the most powerful telescopic camera ever sent to a foreign planet will reveal rocks the size of a small desk. An advanced mineral-mapper will be able to identify water-related deposits in areas as small as a baseball infield. Radar will probe for buried ice and water. A weather camera will monitor the entire planet daily. An infrared sounder will monitor atmospheric temperatures and the movement of water vapor.

The instruments will produce torrents of data. The orbiter can pour data to Earth at about 10 times the rate of any previous Mars mission, using a dish antenna 3 meters (10 feet) in diameter and a transmitter powered by 9.5 square meters (102 square feet) of solar cells. “This spacecraft will return more data than all previous Mars missions combined,” said Jim Graf, project manager for Mars Reconnaissance Orbiter at NASA’s Jet Propulsion Laboratory, Pasadena, Calif.

Scientists will analyze the information to gain a better understanding of changes in Mars’ atmosphere and the processes that have formed and modified the planet’s surface. “We’re especially interested in water, whether it’s ice, liquid or vapor,” said JPL’s Dr. Richard Zurek, project scientist for the orbiter. “Learning more about where the water is today and where it was in the past will also guide future studies about whether Mars has ever supported life.”

A second major job for Mars Reconnaissance Orbiter, in addition to its own investigation of Mars, is to relay information from missions working on the surface of the planet. During its planned five-year prime mission, it will support the Phoenix Mars Scout, which is being built to land on icy soils near the northern polar ice cap in 2008, and the Mars Science Laboratory, an advanced rover under development for launch in 2009.

However, before Mars Reconnaissance Orbiter can begin its main assignments, it will spend half a year adjusting its orbit with an adventurous process called aerobraking. The initial capture by Mars’ gravity on March 10 will put the spacecraft into a very elongated, 35-hour orbit. The planned orbit for science observations is a low-altitude, nearly circular, two-hour loop. To go directly into an orbit like that when arriving at Mars would have required carrying much more fuel for the main thrusters, requiring a larger and more expensive launch vehicle and leaving less payload weight for science instruments. Aerobraking will use hundreds of carefully calculated dips into the upper atmosphere — deep enough to slow the spacecraft by atmospheric drag, but not deep enough to overheat the orbiter.

“Aerobraking is like a high-wire act in open air,” Graf said. “Mars’ atmosphere can swell rapidly, so we need to monitor it closely to keep the orbiter at an altitude that is effective but safe.” Current orbiters at Mars will provide a daily watch of the lower atmosphere, an important example of the cooperative activities between missions at Mars.

Additional information about Mars Reconnaissance Orbiter is available online at:

http://www.nasa.gov/mro

The mission is managed by JPL, a division of the California Institute of Technology, Pasadena, for the NASA Science Mission Directorate, Washington. Lockheed Martin Space Systems, Denver, is the prime contractor for the project and built the spacecraft.

Original Source: NASA News Release