More Evidence for Past Water on Mars

Now that NASA’s Mars Exploration Rover Spirit is finally examining bedrock in the “Columbia Hills,” it is finding evidence that water thoroughly altered some rocks in Mars’ Gusev Crater.

Spirit and its twin, Opportunity, completed successful three-month primary missions on Mars in April and are returning bonus results during extended missions. They remain in good health though beginning to show signs of wear.

On Opportunity, a tool for exposing the insides of rocks stopped working Sunday, but engineers are optimistic that the most likely diagnosis is a problem that can be fixed soon. “It looks like there’s a pebble trapped between the cutting heads of the rock abrasion tool,” said Chris Salvo, rover mission manager at NASA’s Jet Propulsion Laboratory, Pasadena, Calif. “We think we can treat it by turning the heads in reverse, but we are still evaluating the best approach to remedy the situation. There are several options available to us.”

Opportunity originally landed right beside exposed bedrock and promptly found evidence there for an ancient body of saltwater. On the other hand, it took Spirit half a year of driving across a martian plain to reach bedrock in Gusev Crater. Now, Spirit’s initial inspection of an outcrop called “Clovis” on a hill about 9 meters (30 feet) above the plain suggests that water may once have been active at Gusev.

“We have evidence that interaction with liquid water changed the composition of this rock,” said Dr. Steve Squyres of Cornell University, Ithaca, N.Y., principal investigator for the science instruments on both rovers. “This is different from the rocks out on the plain, where we saw coatings and veins apparently due to effects of a small amount of water. Here, we have a more thorough, deeper alteration, suggesting much more water.”

Squyres said, “To really understand the conditions that altered Clovis, we’d like to know what it was like before the alteration. We have the ‘after.’ Now we want the ‘before.’ If we’re lucky, there may be rocks nearby that will give us that.”

Dr. Doug Ming, a rover science team member from NASA’s Johnson Space Center, Houston, said indications of water affecting Clovis come from analyzing the rock’s surface and interior with Spirit’s alpha particle X-ray spectrometer and finding relatively high levels of bromine, sulfur and chlorine inside the rock. He said, “This is also a very soft rock, not like the basaltic rocks seen back on the plains of Gusev Crater. It appears to be highly altered.”

Rover team members described the golf-cart-sized robots’ status and recent findings in a briefing at JPL today.

Opportunity has completed a transect through layers of rock exposed in the southern inner slope of stadium-sized “Endurance Crater.” The rocks examined range from outcrops near the rim down through progressively older and older layers to the lowest accessible outcrop, called “Axel Heiberg” after a Canadian Arctic island. “We found different compositions in different layers,” said Dr. Ralf Gellert, of Max-Planck-Institut fur Chemie, Mainz, Germany. Chlorine concentration increased up to threefold in middle layers. Magnesium and sulfur declined nearly in parallel with each other in older layers, suggesting those two elements may have been dissolved and removed by water.

Small, gray stone spheres nicknamed “blueberries” are plentiful in Endurance just as they were at Opportunity’s smaller landing-site crater, “Eagle.” Pictures from the rover’s microscopic imager show a new variation on the blueberries throughout a reddish-tan slab called “Bylot” in the Axel Heiberg outcrop. “They’re rougher textured, they vary more in size, and they’re the color of the rock, instead of gray,” said Zoe Learner, a science team collaborator from Cornell. “We’ve noticed that in some cases where these are eroding, you can see a regular blueberry or a berry fragment inside.” One possibility is that a water-related process has added a coarser outer layer to the blueberries, she said, adding, “It’s still really a mystery.”

JPL, a division of the California Institute of Technology in Pasadena, manages the Mars Exploration Rover project for NASA’s Science Mission Directorate, Washington. Images and additional information about the project are available from JPL at http://marsrovers.jpl.nasa.gov and from Cornell University at http://athena.cornell.edu .

Original Source: NASA/JPL News Release

Eroded Valleys on Mars

This image, taken by the High Resolution Stereo Camera (HRSC) on board ESA’s Mars Express spacecraft, shows the Dao Valles and Niger Valles, a system of outflow channels on Mars.

The image was taken during orbit 528 in June 2004, and shows the Dao Valles and Niger Valles areas at a point where the north-eastern Hellas impact crater basin and the Hesperia Planum volcanic region meet.

The image is centred at Mars longitude 93? East and latitude 32? South. The image resolution is 40 metres per pixel.

The outflow channel system is, in some areas, 40 kilometres wide. The north-eastern ends of the two valleys are almost 200 metres deeper than the south-western regions which are also shown here. The northern Dao Valles, 2400 metres deep, is about 1000 metres deeper than the more southern Niger Valles.

The structure of the valley floor of the Niger Valles is characterised by terraced basins and chaotic fractures. The floor of the Dao Valles is much smoother, but covered with strongly eroded remnants.

These eroded valleys are in a region which is part of the southern flank of the Hadriaca Patera volcano. The surrounding surface is formed by lava streams, probably in a ‘runoff’ process.

Original Source: ESA News Release

One Year to Go for Mars Reconnaissance Orbiter

With one very busy year remaining before launch, the team preparing NASA’s next mission to Mars has begun integrating and testing the spacecraft’s versatile payload. Possible launch dates from Cape Canaveral, Fla., for NASA’s Mars Reconnaissance Orbiter begin Aug. 10, 2005. The spacecraft will reach Mars seven months later to study the surface, subsurface and atmosphere with the most powerful instrument suite ever flown to the red planet.

“Mars Reconnaissance Orbiter is a quantum leap in our spacecraft and instrument capabilities at Mars,” said James Graf, the mission’s project manager at NASA’s Jet Propulsion Laboratory, Pasadena, Calif. “Weighing 2,180 kilograms [4,806 pounds] at launch, the spacecraft will be the largest ever to orbit Mars. The data rate from the orbiter at Mars back to Earth will be three times faster than a high-speed residential telephone line. This rate will enable us to return a tremendous amount of data and dramatically increase our understanding of this mysterious planet.”

JPL’s Dr. Richard Zurek, project scientist for Mars Reconnaissance Orbiter, said, “This capability is needed to achieve the higher-resolution imaging, spectral mapping, atmospheric profiling and subsurface probing that will allow us to follow up on the exciting discoveries of the current Mars missions.”

Workers at Lockheed Martin Space Systems, Denver, have been building the orbiter for more than a year and have reached the final assembly stage. Flight software is 96 percent complete. Assembly of the launch vehicle, an Atlas V, has begun at the same facility where the orbiter is being completed and tested. This will be the first interplanetary mission hitched to an Atlas since 1973. The Mars Reconnaissance Orbiter team now numbers about 175 people at Lockheed Martin and 110 at JPL.

Kevin McNeill, Lockheed Martin’s program manager for the orbiter, said, “Our team has completed integration and testing of a majority of the spacecraft’s subsystems. In the next few months, we’ll integrate and test the science instruments on the orbiter, followed by environmental testing through early next year. We look forward to getting to the Cape next spring and integrating with the Atlas V launch vehicle. We’re all very excited about getting to Mars and returning data for the science teams to evaluate.”

The spacecraft’s six science instruments are in the final stages of assembly, testing and calibration at several locations for delivery in coming weeks. The payload also includes a relay telecommunications package called Electra and two technology demonstrations to support planning of future Mars missions. “Electra was integrated with the spacecraft and tested in July,” Graf said. “The next payload elements to be integrated will be the Mars climate sounder and the compact reconnaissance imaging spectrometer for Mars.” The climate sounder, from JPL, will quantify the martian atmosphere’s vertical variations in water vapor, dust and temperature; the imaging spectrometer, from Johns Hopkins Applied Physics Laboratory of Laurel, Md., will scan the surface to look for water-related minerals at unprecedented scales, extending discoveries made by NASA’s Mars Exploration Rovers.

The largest telescopic camera ever sent into orbit around another planet, called the high resolution imaging science experiment, will reveal Mars surface features as small as a kitchen table. Ball Aerospace, Boulder, Colo., is building it for the University of Arizona, Tucson. The orbiter will also carry three other cameras. Two come from Malin Space Sciences, San Diego: the context camera for wide-swath, high-resolution pictures, and the Mars multi-color imager with its fish-eye lens for tracking changes in weather and variations in atmospheric ozone. An optical navigation camera from JPL will use positions of Mars’ two moons to demonstrate precision navigation for future missions.

The Italian Space Agency is providing the orbiter’s shallow radar sounding instrument, designed to probe below the surface to discover evidence of underground layers of ice, rock and, perhaps, melted water.

Another technology demonstration from JPL will allow comparison of a higher-frequency, more-efficient radio band with the band commonly used for interplanetary communications. This may allow future missions to return more data with the same expended power.

NASA?s chief scientist for Mars, Dr. Jim Garvin, added, “We build our science strategy for Mars around the next-generation reconnaissance this spacecraft is to provide, with its revolutionary remote sensing payload, and we are proud of the impressive progress to date by our Mars Reconnaissance Orbiter team. Mars Reconnaissance Orbiter will tell us where we must send our next wave of robotic explorers, including the Mars Science Laboratory, as well as paving the way for human exploration.”

The Mars Reconnaissance Orbiter 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 is the prime contractor for the project.

Original Source: NASA/JPL News Release

Perspective View of Olympus Mons

This perspective view, taken by the High Resolution Stereo Camera (HRSC) on board ESA’s Mars Express spacecraft, shows the complex caldera of Olympus Mons on Mars, the highest volcano in our Solar System.

Olympus Mons has an average elevation of 22 kilometres and the caldera, or summit crater, has a depth of about 3 kilometres. The data was retrieved during orbit 143 of Mars Express on 24 February 2004. The view is looking north.

The curved striations on the left and foreground, in the southern part of the caldera, are tectonic faults. After lava production has ceased the caldera collapsed over the emptied magma chamber. Through the collapse the surface suffers from extension and so extensional fractures are formed.

The level plain inside the crater on which these fractures can be observed represents the oldest caldera collapse. Later lava production caused new caldera collapses at different locations (the other circular depressions). They have partly destroyed the circular fracture pattern of the oldest one.

This perspective view of the caldera was calculated from the digital elevation model derived from the stereo channels and combined with the nadir and colour channels of the HRSC.

Original Source: ESA News Release

Mars Express Relays Photos from Rovers

ESA?s Mars Express has relayed pictures from one of NASA’s Mars rovers for the first time, as part of a set of interplanetary networking demonstrations. The demonstrations pave the way for future Mars missions to draw on joint interplanetary networking capabilities. ESA and NASA planned these demonstrations as part of continuing efforts to co-operate in space exploration.

On 4 August at 14:24 CEST, as Mars Express flew over one of NASA?s Mars exploration rovers, Opportunity, it successfully received data previously collected and stored by the rover. The data, including 15 science images from the rover’s nine cameras, were then downlinked to ESA?s European Space Operations Centre in Darmstadt (Germany) and immediately relayed to the Mars Exploration Rovers team based at the Jet Propulsion Laboratory in Pasadena, USA.

NASA orbiters Mars Odyssey and Mars Global Surveyor have so far relayed most of the data produced by the rovers since they landed in January. Communication compatibility between Mars Express and the rovers had already been demonstrated in February, although at a low rate that did not convey much data. The 4 August session, at a transmit rate of 42.6 megabits in about six minutes, set a new mark for international networking around another planet.

The success of this demonstration is the result of years of groundwork and was made possible because both Mars Express and the Mars rovers use the same communication protocol. This protocol, called Proximity-1, was developed by the international Consultative Committee for Space Data Systems, an international partnership for standardising techniques for handling space data.

Mars Express was 1400 kilometres above the Martian surface during the 4 August session with Opportunity, with the goal of a reliable transfer of lots of data. Engineers for both agencies plan to repeat this display of international cooperation today, 10 August, with another set of Opportunity images.

?We’re delighted how well this has been working, and thankful to have Mars Express in orbit,? said Richard Horttor of NASA’s Jet Propulsion Laboratory, Pasadena, California, project manager for NASA’s role in Mars Express. JPL engineer Gary Noreen of the Mars Network Office said: ?the capabilities that our international teamwork is advancing this month could be important in future exploration of Mars.?

In addition, Mars Express is verifying two other operating modes with Opportunity and the twin rover, Spirit, from a greater distance. On 3 and 6 August, when Mars Express listened to Spirit, it was about 6000 kilometres above the surface. At this range it successfully tracked a beacon from Spirit, demonstrating a capability that can be used to locate another craft during critical events, such as the descent to a planet?s surface, or for orbital rendez-vous manoeuvres.

?Establishing a reliable communication network around Mars or other planets is crucial for future exploration missions, as it will allow improved coverage and also an increase in the amount of data that can be brought back to Earth,? said Con McCarthy, from ESA?s Mars Express project, ?the tracking mode will enable ESA and NASA to pinpoint a spacecraft?s position more accurately during critical mission phases.?

The final session of the series, scheduled for 13 August with Opportunity, will demonstrate a mode for gaining navigational information from the ?Doppler shift? in the radio signal.

Original Source: ESA News Release

Slides on Olympus Mons

This image from ESA’s Mars Express show the western flank of the shield volcano Olympus Mons in the Tharsis region of the western Martian hemisphere.

The image was taken by the High Resolution Stereo Camera (HRSC) during orbit 143 from an altitude of 266 kilometres. It were taken with a resolution of about 25 metres per pixel and is centred at 222? East and 22? North. North is to the left.

The image shows the western part of the escarpment, rising from the surface level to over 7000 metres. In the foreground, part of the extensive plains west of the escarpment are shown, known as an ‘aureole’ (from the Latin for ‘circle of light’).

To the north and west of the volcano, these ‘aureole’ deposits are regions of gigantic ridges and blocks extending some 1000 kilometres from the summit like petals of a flower. An explanation for the origin of the deposits has challenged planetary scientists for decades.

The most persistent explanation, however, has been landslides. Large masses of shield material can be found in the aureole area. Several indications also suggest a development and resurfacing connected to glacial activity.

Original Source: ESA News Release

New Perspective on Melas Chasma

This image of the southern part of Valles Marineris, called Melas Chasma, was obtained by the High Resolution Stereo Camera (HRSC) on board the ESA Mars Express spacecraft.

This image was taken at a resolution of approximately 30 metres per pixel. The displayed region is located at the southern rim of the Melas Chasma, centred at Mars latitude 11? S and Mars longitude 286? E. The images were taken on orbit 360 of Mars Express.

This perspective view has been turned in such a way that the observer has a view of the southern scarp, almost 5000 metres high. The basin on the floor of the valley is on the opposite side, bordered by a ridge.

On its flanks it is possible to make out some layering. However, the nature of the bright material, possibly some kind of deposit, is still unknown.

This perspective view was created by using the nadir (vertical view) channel and one stereo channel of the HRSC to produce a digital model of the terrain. Please note that image resolution has been reduced for use on the internet.

Original Source: ESA News Release

Public Invited to Help Catalog Mars

NASA scientists have modified a scientific Web site so the general public can inspect big regions and smaller details of Mars’ surface, a planet whose alien terrain is about the same area as Earth’s continents.

After adding ‘computer tools’ to the ‘Marsoweb’ Internet site, NASA scientists plan to ask volunteers from the public to virtually survey the vast red planet to look for important geologic features hidden in thousands of images of the surface. The Web site is located at:

http://marsoweb.nas.nasa.gov/landingsites/index.html

“The initial reason to create Marsoweb was to help scientists select potential Mars landing sites for the current Mars Exploration Rover (MER) mission,” according to Virginia Gulick, a scientist from the SETI Institute, Mountain View, Calif., who works at NASA Ames Research Center, located in California’s Silicon Valley. “The Web site was designed just for Mars scientists so they could view Mars data easily,” she added.

But when the first Mars Exploration Rover landed on Mars in January, the general public discovered Marsoweb. More than a half million ‘unique visitors’ found the page, and the Web experienced about 26.7 million ‘hits’ in January.

“An interactive data map on Marsoweb allows users to view most Mars data including images, thermal inertia, geologic and topographical maps and engineering data that includes rock abundance,” Gulick said. Thermal inertia is a material’s capacity to store heat (usually in daytime) and conduct heat (often at night). “The engineering data give scientists an idea of how smooth or rocky the local surface is,” Gulick explained.

To examine a large number of distinctive or interesting geologic features on the red planet close up would take an army of people because Mars’ land surface is so big. Such a multitude of explorers – modern equivalents of America’s early pioneers – may well survey details of Mars through personal computers.

Researchers hope that volunteers will help with an upcoming Mars imaging experiment. NASA scientists are getting ready for the High Resolution Imaging Science Experiment (HiRISE) that will fly on the Mars Reconnaissance Orbiter (MRO) mission, slated for launch in August 2005. Gulick, co-investigator and education and public outreach lead of the HiRISE team, said that the experiment’s super high-resolution camera will be able to capture images of objects on Mars’ surface measuring about a yard (one meter) wide.

User-friendly ‘Web tools’ soon will be available to the science community and the public to view and analyze HiRISE images beginning in November 2006 and to submit image observation requests, according to HiRISE scientists. If all goes according to plan, a request form will be on the Internet for use by scientists and the public about the time of the Mars Reconnaissance Orbiter launch in 2005. Marsoweb computer scientist Glenn Deardorff, Gulick and other HiRISE team members are now designing Web-friendly software ‘tools’ to allow the public to examine and evaluate HiRISE images.

“We will ask volunteers to help us create ‘geologic feature’ databases of boulders, gullies, craters – any kind of geologic feature that may be of interest,” Gulick explained. “Scientists or students can use these data bases to propose theories about Mars that could be proven by future exploration.”

Preliminary details about Mars Reconnaissance Orbiter HiRISE’s exploration of Mars are on the World Wide Web at:

http://marsoweb.nas.nasa.gov/hirise/

The current Marsoweb site includes animated ‘fly-throughs’ of some Mars locations. The site also permits users to fine-tune Mars images for brightness, contrast and sharpness as well as make other adjustments.

NASA’s Jet Propulsion Laboratory, operated by the California Institute of Technology in Pasadena, Calif., manages the Mars Exploration Rover and Mars Reconnaissance Orbiter missions for the NASA Office of Space Science, Washington, D.C.

Original Source: NASA News Release

Fractured Crater on Mars

This perspective image of a fractured crater near Valles Marineris on Mars was obtained by the High Resolution Stereo Camera (HRSC) on board the ESA Mars Express spacecraft.

The image was taken during orbit 61 in January 2004 with a resolution of 12. 5 metres per pixel. It shows part of a cratered landscape to the north of the Valles Marineris, at 0.6? S latitude and 309? E longitude, with this crater having a fractured base.

This crater has a rim diameter of 27.5 kilometres and is about 800 metres deep. It is not known yet how these fractures are generated. On Earth, polygonal fractures may occur in contracting material, which breaks at weak zones. For example, we may see this appearing in cooled lava, dried clay or frozen ground.

Original Source: ESA News Release

Spirit’s Got a Bad Wheel

As winter approaches on Mars, NASA’s Opportunity rover continues to inch deeper into the stadium-sized crater dubbed “Endurance.” On the other side of the planet, the Spirit rover found an intriguing patch of rock outcrop while preparing to climb up the “Columbia Hills” backward. This unusual approach to driving is part of a creative plan to accommodate Spirit’s aging front wheel.

Spirit, with an odometer reading of over 3.5 kilometers (2.2 miles), has already traveled six times its designed capacity. Its right front wheel has been experiencing increased internal resistance, and recent efforts to mitigate the problem by redistributing the wheel’s lubricant through rest and heating have been only partially successful.

To cope with the condition, rover planners have devised a roundabout strategy. They will drive the rover backward on five wheels, rotating the sixth wheel only sparingly to ensure its availability for demanding terrain. “Driving may take us a little bit longer because it is like dragging an anchor,” said Joe Melko, a rover engineer at NASA’s Jet Propulsion Laboratory, Pasadena, Calif. “However, this approach will allow us to continue doing science much longer than we ever thought possible.”

On Thursday, July 15, Spirit successfully drove 8 meters (26 feet) north along the base of the Columbia Hills backward, dragging its faulty wheel. The wheel was activated about 10 percent of the time to surmount obstacles and to pull the rover out of trenches dug by the immobile wheel.

Along the way, Spirit drove over what scientists had been hoping to find in the hills — a slab of rock outcrop that may represent some of the oldest rocks observed in the mission so far. Spirit will continue to drive north, where it likely will encounter more outcrop. Ultimately, the rover will drive east and hike up the hills backward using all six wheels.

“A few months ago, we weren’t sure if we’d make it to the hills, and now here we are preparing to drive up into them,” said Dr. Matt Golombek, a rover science-team member from JPL. “It’s very exciting.”

For the past month, the Spirit rover has been parked near several hematite-containing rocks, including “Pot of Gold,” conducting science studies and undergoing a long-distance “tuneup” for its right front wheel.

Driving with the wheel disabled means that corrections might have to be made to the rover’s steering if it veers off its planned path. This limits Spirit’s accuracy, but rover planners working at JPL’s rover test facility have come up with some creative commands that allow the rover to auto-correct itself to a limited degree.

As Spirit prepares to climb upward, Opportunity is rolling downward. Probing increasingly deep layers of bedrock lining the walls of Endurance Crater at Meridiani Planum, the rover has observed a puzzling increase in the amount of chlorine. Data from Opportunity’s alpha particle X-ray spectrometer show that chlorine is the only element that dramatically rises with deepening layers, leaving scientists to wonder how it got there. “We do not know yet which element is bound to the chlorine,” said Dr. Jutta Zipfel, a rover science-team member from the Max Planck Institute for Chemistry, Mainz, Germany.

Opportunity will roll down even farther into the crater in the next few days to see if this trend continues. It also will investigate a row of sharp, teeth-like features dubbed “Razorback,” which may have formed when fluid flowed through cracks, depositing hard minerals. Scientists hope the new data will help put together the pieces of Meridiani’s mysterious and watery past. “Razorback may tell us more about the history of water at Endurance Crater,” said Dr. Jack Farmer, a rover science-team member from Arizona State University, Tempe.

Rover planners are also preparing for the coming Martian winter, which peaks in mid-September. Dwindling daily sunshine means the rovers will have less solar power and take longer to recharge. Periods of rest and “deep sleep” will allow the rovers to keep working through the winter at lower activity levels. Orienting the rovers’ solar panels toward the north will also elevate power supplies. “The rovers might work a little bit more every day, or a little bit more every other day. We will see how things go and remain flexible,” said Jim Erickson, project manager for the Mars Exploration Rover mission at JPL.

JPL, a division of the California Institute of Technology in Pasadena, manages the Mars Exploration Rover project for NASA’s Office of Space Science, Washington.

Images and additional information about the project are available on the Internet at http://marsrovers.jpl.nasa.gov and http://athena.cornell.edu

Original Source: NASA/JPL News Release