MARS EXPRESS
Granicus and Tinjar Valles

ESA

28 July 2006

These images, taken by the High Resolution Stereo Camera (HRSC) on
board ESA's Mars Express spacecraft, show the regions of Granicus Valles
and Tinjar Valles, which may have been formed partly through the action
of subsurface water, due to a process known as sapping.


Granicus Valles and Tinjar Valles (Photo: ESA)
vergrößern

The HRSC obtained these images during orbit 1383 at a ground resolution of approximately 23.7 metres per pixel. The images have been rotated 90 degrees counter-clockwise, so that North is to the left.

They show the regions of Granicus Valles and Tinjar Valles, lying at approximately 26.8° North and 135.7° East. The northwest-aligned Granicus Valles and Tinjar Valles are part of the Utopia-Planitia region, an area thought to be covered by a layer of lava that flowed from the northwest flanks of Elysium Mons into the Utopia-Planitia Basin.

Today, this once-smooth volcanic plain is incised by channels of variable size and appearance, including Granicus Valles (towards the West) and Tinjar Valles (towards the North).

Both channel systems evolve from a single main channel entering the image scene from southeast (upper right), exhibiting an approximate width of 3 km and extending 300 m below the surrounding terrain at maximum. The impressive sinuous lava channel emanates from the mouth of a radial, a circular drainage area, and runs to the Elysium rise trending into a graben, which is terrain dissected by tectonic deformation.

This narrow, straight, 4-km wide and 120-km long graben is interpreted as the source of both lava flows and debris flows that carved Granicus and Tinjar Valles. Similar Elysium flank grabens at higher elevations lack outflow channels. This elevation dependence leads scientists to suggest that subsurface water, released by volcanic activity, has later played a role in shaping the channels visible today.

The colour scene was derived from the three HRSC-colour channels and the nadir channel. The 3D anaglyph image was calculated from the nadir and one stereo channel. Image resolution has been decreased for use on the internet.


Source: esa.int



Wikipedia: Mars

Wikipedia: Mars Express

Cool! Utopia planitia eh? They probably have condoes over looking the valleys in TNGs time.

Mars Exploration Rovers
Winter Solstice on Mars:
Rovers Look Forward to A Second Martian Spring

7 August 2006

Like the fabled tortoise that, in the race with the hare, moves slowly yet accomplishes
much, NASA's Mars Exploration Rover Spirit has continued to make progress little by little,
while essentially running in place.

Eking out a steady stream of scientific data as solar power levels have plunged to a seasonal low during the rover's second Martian mid-winter, Spirit has discovered meteorites that might otherwise have been missed and completed work on a 360-degree, full-color panorama of its surroundings. The rover has collected long-term observations of the Martian atmosphere, rocks, and soils under varying conditions of sunlight, temperature, and wind.


Spirit acquired this view of the Martian sunset from Gusev Crater on
April 23, 2005. Using data from images such as this, scientists have
learned that twilight on Mars is longer than on Earth, lasting for up to two
hours before sunrise or after sunset. Dust high in the atmosphere scatters
light to the night side of the planet. Similar twilights are seen on Earth
following major volcanic eruptions.
Image Credit:NASA/JPL-Caltech/Cornell/Texas A&M
+ View larger image

"Spirit has conducted a regular routine of scientific observations," said Jake Matijevic, rover engineering team chief, "though they haven't been very extensive each day because the energy levels don't allow that. After the solstice, we'll turn the rover to investigate a different part of the surface. We'll move very carefully to preserve our tilt toward the sun."

The winter solstice falls on Tuesday, Aug. 8, 2006, Spirit’s 923rd sol, or Martian day, of exploration. Since April, the rover has been parked on an outcrop known as "Low Ridge Haven," tilted 11 degrees to the north.


Opportunity Continues Trek

On the opposite side of the planet, Spirit's twin, Opportunity, continues to advance toward Victoria Crater, the largest crater yet visited on the surface of Mars. While exploring Martian plains north of the equator, Opportunity, too, has experienced lower power levels during the southern hemisphere winter, though not to the same degree as Spirit.


Opportunity took this approximate true-color mosaic of images of "Beagle Crater" from a distance of about 25 meters (82 feet). The crater is thought to be relatively young based on its prominent, raised rim and surrounding ejecta that have not been eroded away or buried by sand.
Image credit: NASA/JPL-Caltech/Cornell
+ View larger image

Opportunity recently arrived at another, smaller crater known as "Beagle Crater," which is 35 meters (115 feet) wide. Scientists plan to spend some time examining rocks that were excavated onto the surface during the impact that formed the crater. Opportunity is collecting full-color panoramic images of the site.

Like Spirit, Opportunity will have more power for science operations as the days grow longer before and after the vernal equinox on Feb. 8, 2006, when the lengths of the day and night will be equal. On Earth, the vernal equinox is considered the official start of spring.


Source: NASA.gov



Wikipedia: Mars

Wikipedia: Mars Exploration Rovers

NASA's Mars Rover and Orbiter Team
Examines Victoria Crater

October 6, 2006

NASA's long-lived robotic rover Opportunity is beginning to explore layered
rocks in cliffs ringing the massive Victoria crater on Mars.

While Opportunity spent its first week at the crater, NASA's newest eye in
the Martian sky photographed the rover and its surroundings from above.
The level of detail in the photo from the high-resolution camera on the
Mars Reconnaissance Orbiter will help guide the rover's exploration of
Victoria.


An image from NASA's Mars Reconnaissance Orbiter shows the Mars
Exploration Rover Opportunity near the rim of "Victoria Crater."
Image credit: NASA/JPL/UA
+ High resolution version (1.14 MB)

"This is a tremendous example of how our Mars missions in orbit and on the surface are designed to reinforce each other and expand our ability to explore and discover," said Doug McCuistion, director of NASA's Mars Exploration Program in Washington. "You can only achieve this compelling level of exploration capability with the sustained exploration approach we are conducting at Mars through integrated orbiters and landers."

"The combination of the ground-level and aerial view is much more powerful than either alone," said Steve Squyres of Cornell University, Ithaca, N.Y. Squyres is principal investigator for Opportunity and its twin, Spirit. "If you were a geologist driving up to the edge of a crater in your jeep, the first thing you would do would be to pick up the aerial photo you brought with you and use it to understand what you're seeing from ground level. That's exactly what we're doing here."

Images from NASA's Mars Global Surveyor, orbiting the red planet since 1997, prompted the rover team to choose Victoria two years ago as the long-term destination for Opportunity. The images show the one-half-mile-wide crater has scalloped edges of alternating cliff-like high, jutting ledges and gentler alcoves. The new image by the Mars Reconnaissance Orbiter adds significantly more detail.

Exposed geological layers in the cliff-like portions of Victoria's inner wall appear to record a longer span of Mars' environmental history than the rover has studied in smaller craters. Victoria is five times larger than any crater Opportunity has visited during its Martian trek.

High-resolution color images taken by Opportunity's panoramic camera since Sept. 28 reveal previously unseen patterns in the layers. "There are distinct variations in the sedimentary layering as you look farther down in the stack," Squyres said. "That tells us environmental conditions were not constant."

Within two months after landing on Mars in early 2004, Opportunity found geological evidence for a long-ago environment that was wet. Scientists hope the layers in Victoria will provide new clues about whether that wet environment was persistent, fleeting or cyclical.

The rovers have worked on Mars for more than 10 times their originally planned three-month missions. "Opportunity shows a few signs of aging but is in good shape for undertaking exploration of Victoria crater," said John Callas, project manager for the rovers at NASA's Jet Propulsion Laboratory, Pasadena, Calif.

"What we see so far just adds to the excitement. The team has worked heroically for nearly 21 months driving the rover here, and now we're all rewarded with views of a spectacular landscape of nearly 50-foot-thick exposures of layered rock," said Jim Bell of Cornell. Bell is lead scientist for the rovers' panoramic cameras. NASA plans to drive Opportunity from crater ridge to ridge, studying nearby cliffs across the intervening alcoves and looking for safe ways to drive the rover down. "It's like going to the Grand Canyon and seeing what you can from several different overlooks before you walk down," Bell said.

The orbiter images will help the team choose which way to send Opportunity around the rim, and where to stop for the best views. Conversely, the rover's ground-level observations of some of the same features will provide useful information for interpreting orbital images.

"The ground-truth we get from the rover images and measurements enables us to better interpret features we see elsewhere on Mars, including very rugged and dramatic terrains that we can't currently study on the ground," said Alfred McEwen of the University of Arizona, Tucson. He is principal investigator for the orbiter's High Resolution Imaging Science Experiment camera.


Source: NASA.gov





Video Gallery

October 6, Friday

Mars Rover News Briefing ... 47.4 MB

Mars Rover News Briefing Video Feed ... 10.6 MB


Source: space-multimedia.nl.eu.org / NASA TV





Image Gallery


Artist's Concept of Mars Exploration Rover
+ High resolution version (858 KB)


Conceptual drawing of Mars Reconnaissance
Orbiter over Mars
+ High resolution version (120 KB)


September 28, Thursday


PIA08783: 'Victoria Crater' from 'Duck Bay' (28 Sept. 2006)
[Full-Res JPEG] (397 KB)
NASA's Mars rover Opportunity edged 3.7 meters (12 feet) closer to the
top of the "Duck Bay" alcove along the rim of "Victoria Crater" during the
rover's 952nd Martian day, or sol (overnight Sept. 27 to Sept. 28), and
gained this vista of the crater. The rover's navigation camera took the
seven exposures combined into this mosaic view of the crater's interior.
This crater has been the mission's long-term destination for the past 21
Earth months.

The far side of the crater is about 800 meters (one-half mile) away. The
rim of the crater is composed of alternating promontories, rocky points
towering approximately 70 meters (230 feet) above the crater floor, and
recessed alcoves, such as Duck Bay. The bottom of the crater is covered
by sand that has been shaped into ripples by the Martian wind. The rocky
cliffs in the foreground have been informally named "Cape Verde," on the
left, and "Cabo Frio," on the right.

Victoria Crater is about five times wider than "Endurance Crater," which
Opportunity spent six months examining in 2004, and about 40 times
wider than "Eagle Crater," where Opportunity first landed. The great lure
of Victoria is an expectation that the thick stack of geological layers
exposed in the crater walls could reveal the record of past environmental
conditions over a much greater span of time than Opportunity has read
from rocks examined earlier in the mission.

This view is presented as a cylindrical projection with geometric seam
correction.



PIA08807: Layers of 'Cabo Frio' in 'Victoria Crater' (28 Sept. 2006)
[Full-Res JPEG] (397 KB)
This view of "Victoria crater" is looking southeast from "Duck Bay"
towards the dramatic promontory called "Cabo Frio." The small crater in
the right foreground, informally known as "Sputnik", is about 20 meters
(about 65 feet) away from the rover, the tip of the spectacular, layered,
Cabo Frio promontory itself is about 200 meters (about 650 feet) away
from the rover, and the exposed rock layers are about 15 meters (about
50 feet) tall. This is an approximately true color rendering of images
taken by the panoramic camera (Pancam) on NASA's Mars Exploration
Rover Opportunity during the rover's 952nd sol, or Martian day, (Sept. 28,
2006) using the camera's 750-nanometer, 530-nanometer and
430-nanometer filters.



PIA08809: Layers of 'Cape Verde' in 'Victoria Crater' (28 Sept. 2006)
[Full-Res JPEG] (406 KB)
This view of Victoria crater is looking north from "Duck Bay" towards the
dramatic promontory called "Cape Verde." The dramatic cliff of layered
rocks is about 50 meters (about 165 feet) away from the rover and is
about 6 meters (about 20 feet) tall. The taller promontory beyond that is
about 100 meters (about 325 feet) away, and the vista beyond that
extends away for more than 400 meters (about 1300 feet) into the
distance. This is an approximately true color rendering of images taken by
the panoramic camera (Pancam).

PIA08811: Opportunity Traverse Map, 'Eagle' to 'Victoria' (28 Sept. 2006)
[Full-Res JPEG] (641 KB)
[Annotated Image] (156 KB)
NASA's Mars Exploration Rover Opportunity reached the rim of "Victoria
Crater" on Sept. 27, 2006, during the 951st Martian day, or sol, of the
rover's work in the Meridian Planum region of Mars. Opportunity drove
9.28 kilometers (5.77 miles) in the explorations that took it from "Eagle
Crater," where it landed in January 2004, eastward to "Endurance Crater,"
which it investigated for about half of 2004, then southward to Victoria.

This map of Opportunity's trek so far is overlaid onto images taken by the
Mars Orbiter Camera on NASA's Mars Global Surveyor. Victoria is about
800 meters (one-half mile) in diameter, or about five times wider than
Endurance and 40 times wider than Eagle. The scale bar at lower right
shows the length of 800 meters (0.50 mile). North is up.


October 3, Tuesday


PIA08812: The Opportunity Rover at 'Victoria Crater' (3 Oct. 2006)
[Full-Res JPEG] (155 KB)
[Annotated Image] (1.0 MB)
This image from the High Resolution Imaging Science Experiment on
NASA's Mars Reconnaissance Orbiter shows the Mars Exploration Rover
Opportunity near the rim of "Victoria crater." Victoria is an impact crater
about 800 meters (half a mile) in diameter at Meridiani Planum near the
equator of Mars. Opportunity has been operating on Mars since January,
2004. Five days before this image was taken, Opportunity arrived at the
rim of Victoria crater, after a drive of more than 9 kilometers (over 5
miles). It then drove to the position where it is seen in this image.

Shown in the image are "Duck Bay," the eroded segment of the crater rim
where Opportunity first arrived at the crater; "Cabo Frio," a sharp
promontory to the south of Duck Bay; and "Cape Verde," another
promontory to the north. When viewed at the highest resolution, this
image shows the rover itself, wheel tracks in the soil behind it, and the
rover's shadow, including the shadow of the camera mast. Since this
image was taken, Opportunity has moved to the very tip of Cape Verde to
perform more imaging of the interior of the crater.



PIA08813: 'Victoria Crater' at Meridiani Planum (3 Oct. 2006)
[Full-Res JPEG] (3.0 MB)
[Annotated Image] (20.4 MB)
This image from the High Resolution Imaging Science Experiment on
NASA's Mars Reconnaissance Orbiter shows "Victoria crater," an impact
crater at Meridiani Planum, near the equator of Mars. The crater is
approximately 800 meters (half a mile) in diameter. It has a distinctive
scalloped shape to its rim, caused by erosion and downhill movement of
crater wall material. Layered sedimentary rocks are exposed along the
inner wall of the crater, and boulders that have fallen from the crater wall
are visible on the crater floor. The floor of the crater is occupied by a
striking field of sand dunes.



PIA08816: Opportunity at Crater's 'Cape Verde' (3 Oct. 2006)
[Full-Res JPEG] (258 KB)
[Annotated Image] (1.14 MB)
This image from the High Resolution Imaging Science Experiment on
NASA's Mars Reconnaissance Orbiter shows the Mars Exploration Rover
Opportunity near the rim of "Victoria Crater." Victoria is an impact crater
about 800 meters (half a mile) in diameter at Meridiani Planum near the
equator of Mars. Opportunity has been operating on Mars since January,
2004. Five days before this image was taken, Opportunity arrived at the
rim of Victoria, after a drive of more than 9 kilometers (over 5 miles). It
then drove to the position where it is seen in this image.

Shown in the image are "Duck Bay," the eroded segment of the crater rim
where Opportunity first arrived at the crater; "Cabo Frio," a sharp
promontory to the south of Duck Bay; and "Cape Verde," another
promontory to the north. When viewed at the highest resolution, this
image shows the rover itself, wheel tracks in the soil behind it, and the
rover's shadow, including the shadow of the camera mast. After this
image was taken, Opportunity moved to the very tip of Cape Verde to
perform more imaging of the interior of the crater.


Source: NASA/JPL



Mars
Mars Exploration Rover Mission
Mars Exploration Rover "Spirit"
Mars Exploration Rover "Opportunity"
Mars Reconnaissance Orbiter

I want to emphasize how awesome these images are! I first saw these Mars Reconnaisance Orbiter HiRISE pics in this Planetary Society article. Who ever thought we'd be looking down on our intrepid, little rovers with such high resolution and clarity?!? Who ever thought we'd get a simultaneous view of a feature on Mars with both orbital and ground-based cameras? ...and, yet, this was only a TEST of the MRO's instruments! The science phase of its mission officially begins November 8th!

Chris already linked to larger versions of this above, but I wanted to point to a composite photograph from the linked TPS article that highlights some of the features of Victoria crater:

HiRISE "snaps" Victoria crater (click to enlarge)
The High Resolution Imaging Science Experiement (HiRISE) camera on the Mars Reconnaissance Orbiter (MRO) returned its first images of the Martian surface last week during a test, including this image of Victoria crater.
Credit: NASA / JPL / HiRISE Team

Geeze, we could start printing Mars tourist brochures with these pics!

Communication lost with Mars Global Surveyor

The oldest of four spacecraft currently orbiting Mars, Mars Global Surveyor (MGS), has not been heard from since November 5th, two days before the 10th anniversary of the orbiter's launch into space (November 7th, 1996). A signal received on the 5th indicated that the orbiter had put itself into safe mode, possibly turning its antenna away from Earth. See the original press release for more details.

An artist's concept of Mars Global Surveyor.
(click to enlarge)

The latest news as of this posting tells of a plan to use the Mars Reconnaissance Orbiter's HiRISE camera to locate and photograph MGS beginning this Wednesday, November 15th.

Mars Global Surveyor has produced more science than any of the previous Mars missions combined and has had its science mission extended three times. In July, the Mars Orbiter Camera onboard MGS took its only photograph of Mars' outer moon, Deimos.

I hope they can reestablish contact. That little thing was the best investment made in Mars so far

Sho'Dar, on Nov 15 2006, 02:03 AM, said:

Well, ten years was definently a good run. I wouldn't be incredibly upset if it was lost permanently. But seeing as indications are that MGS has gone into safe mode, it seems that recovery is just a matter of time.

MARS GLOBAL SURVEYOR
Mars Global Surveyor Remains Silent, Feared Lost

21 November 2006

BOULDER, Colorado – In a high-tech game of celestial hide and seek,
a Mars orbiter has tried to image a lost-in-space red planet probe.

NASA’s Mars Reconnaissance Orbiter (MRO) has been used to
attempt locating the space agency’s Mars Global Surveyor (MGS)—all
in an effort to discern what caused the spacecraft to fall silent several
weeks ago.


Mars Global Surveyor
Image: NASA / JPL

But after using several MRO instruments, the true whereabouts of MGS and its overall status are still unknown.

“We may have lost a dear old friend and teacher, Mars Global Surveyor,” said Michael Meyer, lead scientist for the Mars Explorations Program at NASA Headquarters in Washington, D.C.

Meyer took part in an update today from NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, California with scientists, engineers and managers detailing the status of the MGS search and the probe’s past science accomplishments.

The briefing was part-wake, part holding out hope that the errant Mars probe could still be heard from again.

No definitive sighting

The last peep from MGS was on November 5, after notifying ground controllers that it had problems with a balky solar panel. For weeks, attempts to bring the Mars orbiter back on line were met with a silent response from the misbehaving probe.

“In the last two weeks we have not been able to establish communication with the spacecraft in a normal fashion,” said Fuk Li, Mars Program Manager at JPL. Over that period of time more than 800 command files were sent to re-establish communication with MGS, but none of them have been successful, he said.

To help in the search for MGS, the Mars Reconnaissance Orbiter was tasked last Friday, and again Monday to try and spot the MGS within a select region of space.

“Our preliminary analysis so far has not yielded any definitive sighting of MGS,” Li said.

Rover to lend an ear

A next step is use of the Opportunity Mars rover to listen for a low-power antenna on MGS. Earth controllers will try today and tomorrow to activate an MGS antenna to transmit a signal to Opportunity, now sitting near Victoria Crater within Meridiani Planum.

Whatever the rover picks up—if anything—would be relayed to the Mars Odyssey spacecraft also orbiting the red planet for rebroadcast back to Earth.

Jim Erickson, JPL project manager for MRO said that analysis of all the MRO search imagery is still underway. After studying the results from Opportunity’s listen session for MGS, as well as other assessments, a decision on utilizing the MRO again will be weighed, he told SPACE.com.

Tom Thorpe, Project Manager for the MGS at JPL said that the spacecraft’s power can vary considerably if one of its solar panels is turned completely away from the Sun – but is also a situation that creates a marginal spacecraft energy situation.

“The power could be supported on only one panel. As long as we’re getting enough power the spacecraft is capable of maintaining itself. We have attitude gas, for example, that could keep us in this mode for one or two years. It’s anybody’s guess as to where that stuck panel is pointed…but we feel that there’s a good chance that we’re getting enough power to maintain operations,” Thorpe told SPACE.com.

Old-timer and good friend

The Mars Global Surveyor is an old-timer. In fact, it is the oldest of five NASA spacecraft currently active at the red planet - three orbiting Mars while the Spirit and Opportunity Mars rovers continue duties on the planet’s surface. Joining in on the exploration is the Mars Express, also circling Mars and is operated by the European Space Agency (ESA).

So far, NASA has not requested any assistance from ESA to help in the quest to bring MGS back to life.

MGS is a long-lived spacecraft that recently celebrated a decade of space exploration after its launch on November 7, 1996. The robust Mars probe has far surpassed its initial warranty of a full martian year (roughly two Earth years), yielding a wealth of discoveries over a span of time. MGS had its mission extended repeatedly, most recently in October of this year.

In total, the Mars Global Surveyor program has been a $377 million investment in opening up the red planet to intensive exploration.

“While we have not exhausted everything that we could do…we believe that the prospect of recovery of MGS is not looking very good at all,” JPL’s Li explained. “It’s been a good friend…and we are certainly feeling we might be losing a good friend from our family here,” he added.

Li said that everyone is still holding out some hope, but are fully prepared for the prospect of never being able to talk to the spacecraft again. “But we are also fully prepared to celebrate the fact that it has been a job well done,” he added.


Source: space.com



Mars
Mars Global Surveyor

Europe joins hunt for missing Mars probe

28 November 2006

NASA has called on the European Space Agency's Mars Express spacecraft to look for the missing Mars Global Surveyor (MGS) after the Opportunity rover failed to locate it by listening for its radio beacon.

The 10-year-old MGS was last heard from on 5 November. It reported problems re-pointing one of its solar power arrays shortly before going silent (see NASA struggles to contact lost Mars probe).

NASA called on its Mars Reconnaissance Orbiter (MRO) to try to take pictures of MGS on 17 and 20 November. But the images did not reveal the spacecraft, perhaps because MGS had shifted in its orbit since last contact (see Mars probe probably lost forever).

After MRO failed to spot the spacecraft, NASA turned to its Opportunity rover to continue the search. Opportunity listened for MGS's radio beacon on 21 and 22 November, but heard nothing.

Roving search

All these failed attempts do not necessarily mean MGS is dead, says the spacecraft's manager Thomas Thorpe of NASA's Jet Propulsion Laboratory in Pasadena, California, US. "The antenna that transmits the signal is on one side of MGS, and that may or may not have been pointed at Mars when we passed over" the rover, he told New Scientist.

The radio beam from MGS's antennas is about 60° wide, giving only about a 1 in 6 chance of it reaching the rover, since MGS's orientation is unknown.

Opportunity's roving twin, Spirit, will try to detect the beacon, too. But Spirit is just emerging from its winter hibernation and will not have enough power to spare for this task until a few weeks from now, Thorpe says.

Pass in the night

In the meantime, the European Space Agency (ESA) is joining the search: "We've asked the Mars Express people to take an image of MGS with their High Resolution Stereo Camera," Thorpe says, adding that the Mars Express HRSC team had agreed to make the attempt. They have not set a date for this attempt, but the earliest opportunity is on 7 December 2006, when the two spacecraft should come within 400 kilometres of each other.

Even though random drift of the spacecraft has led to uncertainty in its position, the field of view of Mars Express's HRSC is wide enough to include the entire area that the spacecraft could be in, Thorpe says.

MRO is just beginning its science observations and is too busy to continue hunting for MGS, he says. But if Mars Express can locate MGS, then a case could be made for a second imaging attempt with MRO, which has the only camera powerful enough to reveal the orientation of the spacecraft and the position of its solar panels, Thorpe says.

This information would help engineers to diagnose and perhaps solve the problem that is preventing the spacecraft from communicating with Earth.

Points of light

The MRO images taken on 17 and 20 November did show two extra points of light that did not correspond to any of the stars expected in the field of view. There had been speculation that these points of light were two pieces of MGS – perhaps the main body of the spacecraft and a broken-off solar panel.

Thorpe says that scenario is unlikely, however. "If those blips were real, they were in two very different orbits, so it's pretty unlikely that both could have come from the spacecraft," he says. It remains possible that one of the points of light is MGS, but they are too dim to draw any firm conclusions, he says. One or both could just be instrument noise, perhaps the result of cosmic rays hitting the camera, he says.

While other probes search for MGS, NASA is beaming commands to it from Earth every day in the hope of reviving it. The agency has been trying various ways of commanding it to turn on its low gain antennas, and also ordering it to rotate in the hope of getting them pointed closer to Earth. But the spacecraft has remained stubbornly silent despite these efforts.


Source: New Scientist Space



A list of some of the mission's important discoveries about Mars from a recent article on the official Mars Global Surveyor website:

• The spacecraft's camera found gullies cut into many slopes that have few, if any, impact craters. This indicates the gullies are geologically young. Scientists interpret this as evidence of action by liquid water, essentially in modern times.
  
  
  
• The mineral-mapping infrared spectrometer found concentrations of a mineral that often forms under wet conditions, fine-grained hematite. This discovery led to selection of a hematite-rich region as the landing site for NASA's Mars Exploration Rover Opportunity.
  
  
  
• Laser altimeter measurements have produced an unprecedented global topographic map of Mars. The instrument revealed a multitude of highly eroded or buried craters too subtle for previous observation, and mapped canyons within the polar ice caps.
  
  
  
• The magnetometer found localized remnant magnetic fields, indicating that Mars once had a global magnetic field like Earth's, shielding the surface from deadly cosmic rays.
  
  
  
• The camera found a fan-shaped area of interweaving, curved ridges interpreted as evidence of an ancient river delta resulting from persistent flow of water over an extended period in the planet's ancient past.
  
  
  
• A long life allowed Global Surveyor to track changes through repeated annual cycles. For three Martian summers in a row, deposits of carbon-dioxide ice near Mars' South Pole shrunk from the previous year's size, suggesting a climate change in progress.

Also, the Mars Reconnaissance Orbiter is presently surveying the northern plains region of Mars in order to find a better landing site for the Phoenix polar lander.

that image looking down on the little rover is amazing, who could of thought a probe could zoom in on something so small with such sharpness

It is a shame NASA lost contact with the MGS, hopefully one of the other probes or the rovers hear it again