MOC View of Mars98 Landing Zone - 12/24/97

NASA Technical Reports Server (NTRS)

1998-01-01

On 12/24/1997 at shortly after 08:17 UTC SCET, the Mars Global Surveyor Mars Orbiter Camera (MOC) took this high resolution image of a small portion of the potential Mars Surveyor '98 landing zone. For the purposes of planning MOC observations, this zone was defined as 75 +/- 2 degrees S latitude, 215 +/- 15 degrees W longitude. The image ran along the western perimeter of the Mars98 landing zone (e.g., near 245oW longitude). At that longitude, the layered deposits are farther south than at the prime landing longitude. The images were shifted in latitude to fall onto the layered deposits. The location of the image was selected to try to cover a range of possible surface morphologies, reliefs, and albedos.

This image is approximately 81.5 km long by 31 km wide. It covers an area of about 2640 sq. km. The center of the image is at 80.46oS, 243.12 degrees W. The viewing conditions are: emission angle 56.30 degrees, incidence angle 58.88 degrees, phase of 30.31 degrees, and 15.15 meters/pixel resolution. North is to the top of the image.

The effects of ground fog, which obscures the surface features(left), has been minimize by filtering (right).

Malin Space Science Systems (MSSS) and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

MOC View of Mars98 Landing Zone - 12/24/97

NASA Technical Reports Server (NTRS)

1998-01-01

On 12/24/1997 at shortly after 08:17 UTC SCET, the Mars Global Surveyor Mars Orbiter Camera (MOC) took this high resolution image of a small portion of the potential Mars Surveyor '98 landing zone. For the purposes of planning MOC observations, this zone was defined as 75 +/- 2 degrees S latitude, 215 +/- 15 degrees W longitude. The image ran along the western perimeter of the Mars98 landing zone (e.g., near 245oW longitude). At that longitude, the layered deposits are farther south than at the prime landing longitude. The images were shifted in latitude to fall onto the layered deposits. The location of the image was selected to try to cover a range of possible surface morphologies, reliefs, and albedos.

This image is approximately 83.3 km long by 31.7 km wide. It covers an area of about 2750 sq. km. The center of the image is at 81.97 degrees S, 246.74 degrees W. The viewing conditions are: emission angle 58.23 degrees, incidence angle 60.23 degrees, phase of 30.34 degrees, and 15.49 meters/pixel resolution. North is to the top of the image.

The effects of ground fog, which obscures the surface features(left), has been minimize by filtering (right).

Malin Space Science Systems (MSSS) and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

South Polar Scarps

NASA Technical Reports Server (NTRS)

2003-01-01

MGS MOC Release No. MOC2-438, 31 July 2003

The terrain of the south polar residual ice cap, made up mostly of frozen carbon dioxide, has come to be known by many as 'swiss cheese terrain,' because many areas of the cap resemble slices of swiss cheese. However, not all of the south polar cap looks like a tasty lunch food. This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a series of curving scarps formed by erosion and sublimation of carbon dioxide from the south polar cap. This area is located near 86.3oS, 51.2oW. The image is illuminated by sunlight from the upper left; the area is about 1.5 km (0.9 mi) wide.

Coprates Chasma

NASA Technical Reports Server (NTRS)

1998-01-01

Mars Orbiter Camera (MOC) image of a 10 km by 12 km area of Coprates Chasma (14.7 degrees S, 55.8 degrees W), a ridge with a flat upper surface in the center of Coprates Chasma, which is part of the 6000-km-long Valles Marineris. Rock layers are visible just below the ridge. The gray scale (4.8 m/pixel) MOC image was combined with a Viking Orbiter color view of the same area. The faults of a graben offset beds on the slope to the left.

Figure caption from Science Magazine

Polar Polygon Patterns

NASA Technical Reports Server (NTRS)

2003-01-01

MGS MOC Release No. MOC2-338, 22 April 2003

This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image was taken during southern spring, as the seasonal carbon dioxide frost cap was subliming away. Frost remaining in shallow cracks and depressions reveals a fantastic polygonal pattern. Similar polygons occur in the Earth's arctic and antarctic regions-on Earth such polygons are related to the freeze and thaw of ground ice. The picture covers an area about 3 km (about 1.9 mi) wide near 71.9oS, 11.1oW. Sunlight illuminates the scene from the left.

Fresh Impact Crater and Rays in Tharsis

NASA Technical Reports Server (NTRS)

2002-01-01

The Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) Extended Mission has included dozens of opportunities to point the spacecraft directly at features of interest so that pictures of things not seen during the earlier Mapping Mission can be obtained. The example shown here is a small meteorite impact crater in northern Tharsis near 17.2oN, 113.8oW. Viking Orbiter images from the late 1970's showed at this location what appeared to be a dark patch with dark rays emanating from a brighter center. The MOC team surmised that the dark rays may be indicating the location of afresh crater formed by impact sometime in the past few centuries (since dark ray are quickly covered by dust falling out of the martian atmosphere). All through MOC's Mapping Mission in 1999 and 2000, attempts were made to image the crater as predictions indicated that the spacecraft would pass over the site, but the crater was never seen. Finally, in June 2001, Extended Mission operations allowed the MOC team to point the spacecraft (and hence the camera, which is fixed to the spacecraft)directly at the center of the dark rays, where we expected to find the crater.

The picture on the left (above, A) is a mosaic of three MOC high resolution images and one much lower-resolution Viking image. From left to right, the images used in the mosaic are: Viking 1 516A55, MOC E05-01904, MOCM21-00272, and MOC M08-03697. Image E05-01904 is the one taken in June 2001 by pointing the spacecraft. It captured the impact crater responsible for the rays. A close-up of the crater, which is only 130 meters (427 ft)across, is shown on the right (above, B). This crater is only one-tenth the size of the famous Meteor Crater in northern Arizona.

The June 2001 MOC image reveals many surprises about this feature. For one, the crater is not located at the center of the bright area from which the dark rays radiate. The rays point to the center of this bright area, not the crater. Further, the dark material ejected from the crater--immediately adjacent to the crater rim in the picture on the right (above, B)--is not continuously connected to the larger pattern of rays. Asymmetries in crater form and ejecta patterns are generally believed to occur when the impact is oblique to the surface. The offset of the crater from the center of the rays suggests that the meteor struck at an angle, most likely from the bottom/lower right (south/southeast). The strange geometry of the rays is quite different from that seen for rays associated with impact craters on the Moon and other airless bodies; one possible explanation is that they resulted from disruption of dust on the martian surface by winds generated by the shock wave as the meteor plunged through the martian atmosphere before it struck the ground.

Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

Candor Chasma - Massive (non-layered) material expos

NASA Technical Reports Server (NTRS)

1998-01-01

One of the most striking discoveries of the Mars Global Surveyor mission has been the identification of thousands of meters/feet of layers within the wall rock of the enormous martian canyon system, Valles Marineris.

Valles Marineris was first observed in 1972 by the Mariner 9 spacecraft, from which the troughs get their name: Valles--valleys, Marineris--Mariner.

Some hints of layering in both the canyon walls and within some deposits on the canyon floors were seen in Mariner 9 and Viking orbiter images from the 1970s. The Mars Orbiter Camera on board Mars Global Surveyor has been examining these layers at much higher resolution than was available previously.

MOC images led to the realization that there are layers in the walls that go down to great depths. An example of the wall rock layers can be seen in MOC image 8403, shown above (C).

MOC images also reveal amazing layered outcrops on the floors of some of the Valles Marineris canyons. Particularly noteworthy is MOC image 23304 (D, above), which shows extensive, horizontally-bedded layers exposed in buttes and mesas on the floor of western Candor Chasma. These layered rocks might be the same material as is exposed in the chasm walls (as in 8403--C, above), or they might be rocks that formed by deposition (from water, wind, and/or volcanism) long after Candor Chasma opened up.

In addition to layered materials in the walls and on the floors of the Valles Marineris system, MOC images are helping to refine our classification of geologic features that occur within the canyons. For example, MOC image 25205 (E, above), shows the southern tip of a massive, tongue-shaped massif (a mountainous ridge) that was previously identified as a layered deposit. However, this MOC image does not show layering. The material has been sculpted by wind and mass-wasting--downslope movement of debris--but no obvious layers were exposed by these processes.

Valles Marineris a fascinating region on Mars that holds much potential to reveal information about the early history and evolution of the red planet. The MOC Science Team is continuing to examine the wealth of new data and planning for new Valles Marineris targets once the Mapping Phase of the Mars Global Surveyor mission commences in March 1999.

This image: Massive (non-layered) material exposed in central Candor Chasma. MOC image 25205 subframe shown at 11.7 meters (38.4 feet) per pixel resolution. Image shows the southern tip of a massive 'interior deposit' that points like a giant tongue from Ophir Chasma (to the north) down into the center of Candor Chasma. The ridged and grooved bright unit is the 'interior deposit'. South of this ridged unit is a low elevation surface mantled by dark dunes and sand. Image covers an area approximately 5.7 by 5.7 kilometers (3.5 x 3.5 miles). North is approximately up, illumination is from the lower right. Image 25205 was obtained during Mars Global Surveyor's 252nd orbit at 2:45 p.m. (PDT) on April 20, 1998.

Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

The 1997 Spring Regression of the Martian South Polar Cap: Mars Orbiter Camera Observations

USGS Publications Warehouse

James, P.B.; Cantor, B.A.; Malin, M.C.; Edgett, K.; Carr, M.H.; Danielson, G.E.; Ingersoll, A.P.; Davies, M.E.; Hartmann, W.K.; McEwen, A.S.; Soderblom, L.A.; Thomas, P.C.; Veverka, J.

2000-01-01

The Mars Orbiter cameras (MOC) on Mars Global Surveyor observed the south polar cap of Mars during its spring recession in 1997. The images acquired by the wide angle cameras reveal a pattern of recession that is qualitatively similar to that observed by Viking in 1977 but that does differ in at least two respects. The 1977 recession in the 0o to 120o longitude sector was accelerated relative to the 1997 observations after LS = 240o; the Mountains of Mitchel also detached from the main cap earlier in 1997. Comparison of the MOC images with Mars Orbiter Laser Altimeter data shows that the Mountains of Mitchel feature is controlled by local topography. Relatively dark, low albedo regions well within the boundaries of the seasonal cap were observed to have red-to-violet ratios that characterize them as frost units rather than unfrosted or partially frosted ground; this suggests the possibility of regions covered by CO2 frost having different grain sizes.

Evidence for Recent Liquid Water on Mars: Gullies in Sirenum Fossae Trough

NASA Technical Reports Server (NTRS)

2000-01-01

This mosaic of two Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) images shows about 20 different gullies coming down the south-facing wall of a trough in the Sirenum Fossae/Gorgonum Chaos region of the martian southern hemisphere. Each channel and its associated fan--or apron--of debris appears to have started just below the same hard, resistant layer of bedrock located approximately 100 meters (about 325 feet) below the top of the trough wall. The layer beneath this hard, resistant bedrock is interpreted to be permeable, which allows ground water to percolate through it and--at the location of this trough--seep out onto the martian surface. The channels and aprons only occur on the south-facing slope of this valley created by faults on each side of the trough. The depression is approximately 1.4 km (0.9 mi) across.

The mosaic was constructed from two pictures taken on September 16, 1999, and May 1, 2000. The black line is a gap between the two images that was not covered by MOC. The scene covers an area approximately 5.5 kilometers (3.4 miles) wide by 4.9 km (3.0 mi) high. Sunlight illuminates the area from the upper left. The image is located near 38.5oS, 171.3oW. MOC high resolution images are taken black-and-white (grayscale); the color seen here has been synthesized from the colors of Mars observed by the MOC wide angle cameras and by the Viking Orbiters in the late 1970s.

'Inca City' is Part of a Circular Feature

NASA Technical Reports Server (NTRS)

2002-01-01

MGS MOC Release No. MOC2-319, 8 August 2002 [figure removed for brevity, see original site] 'Inca City' is the informal name given by Mariner 9 scientists in 1972 to a set of intersecting, rectilinear ridges that are located among the layered materials of the south polar region of Mars. Their origin has never been understood; most investigators thought they might be sand dunes, either modern dunes or, more likely, dunes that were buried, hardened, then exhumed. Others considered them to be dikes formed by injection of molten rock (magma) or soft sediment into subsurface cracks that subsequently hardened and then were exposed at the surface by wind erosion. The Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) has provided new information about the 'Inca City' ridges, though the camera's images still do not solve the mystery. The new information comes in the form of a MOC red wide angle context frame taken in mid-southern spring, shown above left and above right. The original Mariner 9 view of the ridges is seen at the center. The MOC image shows that the 'Inca City' ridges, located at 82oS, 67oW, are part of a larger circular structure that is about 86 km (53 mi) across. It is possible that this pattern reflects an origin related to an ancient, eroded meteor impact crater that was filled-in, buried, then partially exhumed. In this case, the ridges might be the remains of filled-in fractures in the bedrock into which the crater formed, or filled-in cracks within the material that filled the crater. Or both explanations could be wrong. While the new MOC image shows that 'Inca City' has a larger context as part of a circular form, it does not reveal the exact origin of these striking and unusual martian landforms.

"Inca City" is Part of a Circular Feature

NASA Image and Video Library

2002-08-07

MGS MOC Release No. MOC2-319, 8 August 2002. "Inca City" is the informal name given by Mariner 9 scientists in 1972 to a set of intersecting, rectilinear ridges that are located among the layered materials of the south polar region of Mars. Their origin has never been understood; most investigators thought they might be sand dunes, either modern dunes or, more likely, dunes that were buried, hardened, then exhumed. Others considered them to be dikes formed by injection of molten rock (magma) or soft sediment into subsurface cracks that subsequently hardened and then were exposed at the surface by wind erosion. The Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) has provided new information about the "Inca City" ridges, though the camera's images still do not solve the mystery. The new information comes in the form of a MOC red wide angle context frame taken in mid-southern spring, shown above left and above right. The original Mariner 9 view of the ridges is seen at the center. The MOC image shows that the "Inca City" ridges, located at 82°S, 67°W, are part of a larger circular structure that is about 86 km (53 mi) across. It is possible that this pattern reflects an origin related to an ancient, eroded meteor impact crater that was filled-in, buried, then partially exhumed. In this case, the ridges might be the remains of filled-in fractures in the bedrock into which the crater formed, or filled-in cracks within the material that filled the crater. Or both explanations could be wrong. While the new MOC image shows that "Inca City" has a larger context as part of a circular form, it does not reveal the exact origin of these striking and unusual martian landforms. http://photojournal.jpl.nasa.gov/catalog/PIA03918

Mars Daily Global Image from April 1999

NASA Image and Video Library

2000-09-08

Twelve orbits a day provide NASA Mars Global Surveyor MOC wide angle cameras a global napshot of weather patterns across the planet. Here, bluish-white water ice clouds hang above the Tharsis volcanoes.

Dunes in Brashear

NASA Image and Video Library

2006-01-08

This Mars Global Surveyor MGS Mars Orbiter Camera MOC image shows a field of dark sand dunes on the northwestern floor of Brashear Crater. The dunes formed largely from winds that blew from the southeast lower right

Olympus Mons in Color

NASA Technical Reports Server (NTRS)

1997-01-01

Sections of MOC images P024_01 and P024_02, shown here in color composite form, were acquired with the low resolution red and blue wide angle cameras over a 5 minute period starting when Mars Global Surveyor was at its closest point to the planet at the beginning of its 24th orbit (around 4:00 AM PDT on October 20, 1997). To make this image, a third component (green) was synthesized from the red and blue images. During the imaging period, the camera was pointed straight down towards the martian surface, 176 km (109 miles) below the spacecraft. During the time it took to acquire the image, the spacecraft rose to an altitude of 310 km (193 miles). Owing to data camera scanning rate and data volume constraints, the image was acquired at a resolution of roughly 1 km (0.609 mile) per pixel. The image shown here covers an area from 12o to 26o N latitude and 126o N to 138o W longitude. The image is oriented with north to the top.

As has been noted in other MOC releases, Olympus Mons is the largest of the major Tharsis volcanoes, rising 25 km (15.5 miles) and stretching over nearly 550 km (340 miles) east-west. The summit caldera, a composite of as many as seven roughly circular collapse depressions, is 66 by 83 km (41 by 52 miles) across. Also seen in this image are water-ice clouds that accumulate around and above the volcano during the late afternoon (at the time the image was acquired, the summit was at 5:30 PM local solar time). To understand the value of orbital observations, compare this image with the two taken during approach (PIA00929 and PIA00936), that are representative of the best resolution from Earth.

Through Monday, October 28, the MOC had acquired a total of 132 images, most of which were at low sun elevation angles. Of these images, 74 were taken with the high resolution narrow angle camera and 58 with the low resolution wide angle cameras. Twenty-eight narrow angle and 24 wide angle images were taken after the suspension of aerobraking. These images, including the one shown above, are among the best returned so far.

Launched on November 7, 1996, Mars Global Surveyor entered Mars orbit on Thursday, September 11, 1997. The original mission plan called for using friction with the planet's atmosphere to reduce the orbital energy, leading to a two-year mapping mission from close, circular orbit (beginning in March 1998). Owing to difficulties with one of the two solar panels, aerobraking was suspended in mid-October and is scheduled to resume in mid-November. Many of the original objectives of the mission, and in particular those of the camera, are likely to be accomplished as the mission progresses.

Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

Valley Near Nilus Chaos

NASA Technical Reports Server (NTRS)

2003-01-01

MGS MOC Release No. MOC2-504, 5 October 2003

This August 2003 Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a valley near Nilus Chaos, around 25.2oN, 80.3oW. The scene has a uniform albedo, indicating that all of the landforms are probably mantled by fine, bright dust. Dark streaks on the valley walls indicate places where recent dust avalanches have occurred. The ripple-like dune features on the valley floor were formed by wind, but today they are inactive and covered with dust. A few craters, created by impacting debris, have formed on the dunes, again attesting to their inactivity in the modern martian environment. The image covers an area 3 km (1.9 mi) wide; it is illuminated by sunlight from the lower left.

Observational Tests of the Mars Ocean Hypothesis: Selected MOC and MOLA Results

NASA Technical Reports Server (NTRS)

Parker, T. J.; Banerdt, W. B.

1999-01-01

We have begun a detailed analysis of the evidence for and topography of features identified as potential shorelines that have been im-aged by the Mars Orbiter Camera (MOC) during the Aerobraking Hiatus and Science Phasing Orbit periods of the Mars Global Surveyor (MGS) mission. MOC images, comparable in resolution to high-altitude terrestrial aerial photographs, are particularly well suited to address the morphological expressions of these features at scales comparable to known shore morphologies on Earth. Particularly useful are examples of detailed relationships between potential shore features, such as erosional (and depositional) terraces have been cut into "familiar" pre-existing structures and topography in a fashion that points to a shoreline interpretation as the most likely mechanism for their formation. Additional information is contained in the original extended abstract.

Medusae Fossae Formation

NASA Technical Reports Server (NTRS)

1998-01-01

An exotic terrain of wind-eroded ridges and residual smooth surfaces are seen in one of the highest resolution images ever taken of Mars from orbit. The Medusae Fossae formation is believed to be formed of the fragmental ejecta of huge explosive volcanic eruptions. When subjected to intense wind-blasting over hundreds of millions of years, this material erodes easily once the uppermost tougher crust is breached. In the Mars Orbiter Camera (MOC) image shown on the right, the crust, or cap rock, can be seen in the upper right part of the picture. The finely-spaced ridges are similar to features on Earth called yardangs, which are formed by intense winds plucking individual grains from, and by wind-driven sand blasting particles off, sedimentary deposits.

The MOC image was taken on October 30, 1997 at 11:05 AM PST, shortly after the Mars Global Surveyor spacecraft's 31st closest approach to Mars. The image covers an area 3.6 X 21.5 km (2.2 X 13.4 miles) at 3.6 m (12 feet) per picture element--craters only 11 m (36 feet, about the size of a swimming pool) across can be seen. The context image (left; the best Viking view of the area; VO 1 387S34) has a resolution of 240 m/pixel, or 67 times lower resolution than the MOC frame.

Malin Space Science Systems (MSSS) and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

Western Candor Chasma - Layers exposed near the middle

NASA Technical Reports Server (NTRS)

1998-01-01

One of the most striking discoveries of the Mars Global Surveyor mission has been the identification of thousands of meters/feet of layers within the wall rock of the enormous martian canyon system, Valles Marineris.

Valles Marineris was first observed in 1972 by the Mariner 9 spacecraft, from which the troughs get their name: Valles--valleys, Marineris--Mariner.

Some hints of layering in both the canyon walls and within some deposits on the canyon floors were seen in Mariner 9 and Viking orbiter images from the 1970s. The Mars Orbiter Camera on board Mars Global Surveyor has been examining these layers at much higher resolution than was available previously.

MOC images led to the realization that there are layers in the walls that go down to great depths. An example of the wall rock layers can be seen in MOC image 8403, shown above (C).

MOC images also reveal amazing layered outcrops on the floors of some of the Valles Marineris canyons. Particularly noteworthy is MOC image 23304 (D, above), which shows extensive, horizontally-bedded layers exposed in buttes and mesas on the floor of western Candor Chasma. These layered rocks might be the same material as is exposed in the chasm walls (as in 8403--C, above), or they might be rocks that formed by deposition (from water, wind, and/or volcanism) long after Candor Chasma opened up.

In addition to layered materials in the walls and on the floors of the Valles Marineris system, MOC images are helping to refine our classification of geologic features that occur within the canyons. For example, MOC image 25205 (E, above), shows the southern tip of a massive, tongue-shaped massif (a mountainous ridge) that was previously identified as a layered deposit. However, this MOC image does not show layering. The material has been sculpted by wind and mass-wasting--downslope movement of debris--but no obvious layers were exposed by these processes.

Valles Marineris a fascinating region on Mars that holds much potential to reveal information about the early history and evolution of the red planet. The MOC Science Team is continuing to examine the wealth of new data and planning for new Valles Marineris targets once the Mapping Phase of the Mars Global Surveyor mission commences in March 1999.

Layers exposed near the middle of western Candor Chasma. MOC image 23304 subframe shown at 10.7 meters (35 feet) per pixel. Two layered buttes (upper right and lower right) and a layered or stepped mesa (center right) are shown. The image covers an area approximately 5.5 by 5.5 kilometers (3.4 x 3.4 miles). North is approximately up, illumination is from the lower right. Image 23304 was obtained during Mars Global Surveyor's 233rd orbit at 9:23 a.m. (PDT) on April 11, 1998.

Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

Toe of Ganges Chasma Landslide ( 8.0 S, 44.4W)

NASA Technical Reports Server (NTRS)

2001-01-01

This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows shear striations, dark dunes banked up against the toe of the slide and over-riding light-toned ripples and boulders on surface of slide. These features can be used to determine quantitative aspects of surface processes.

Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

Mars Orbiter Camera Views the 'Face on Mars' - Comparison with Viking

NASA Technical Reports Server (NTRS)

1998-01-01

Shortly after midnight Sunday morning (5 April 1998 12:39 AM PST), the Mars Orbiter Camera (MOC) on the Mars Global Surveyor (MGS) spacecraft successfully acquired a high resolution image of the 'Face on Mars' feature in the Cydonia region. The image was transmitted to Earth on Sunday, and retrieved from the mission computer data base Monday morning (6 April 1998). The image was processed at the Malin Space Science Systems (MSSS) facility 9:15 AM and the raw image immediately transferred to the Jet Propulsion Laboratory (JPL) for release to the Internet. The images shown here were subsequently processed at MSSS.

The picture was acquired 375 seconds after the spacecraft's 220th close approach to Mars. At that time, the 'Face', located at approximately 40.8o N, 9.6o W, was 275 miles (444 km) from the spacecraft. The 'morning' sun was 25o above the horizon. The picture has a resolution of 14.1 feet (4.3 meters) per pixel, making it ten times higher resolution than the best previous image of the feature, which was taken by the Viking Mission in the mid-1970's. The full image covers an area 2.7 miles (4.4 km) wide and 25.7 miles (41.5 km) long.

In this comparison, the best Viking image has been enlarged to 3.3 times its original resolution, and the MOC image has been decreased by a similar 3.3 times, creating images of roughly the same size. In addition, the MOC images have been geometrically transformed to a more overhead projection (different from the mercator map projection of PIA01440 & 1441) for ease of comparison with the Viking image. The left image is a portion of Viking Orbiter 1 frame 070A13, the middle image is a portion of MOC frame shown normally, and the right image is the same MOC frame but with the brightness inverted to simulate the approximate lighting conditions of the Viking image.

Processing Image processing has been applied to the images in order to improve the visibility of features. This processing included the following steps:

The image was processed to remove the sensitivity differences between adjacent picture elements (calibrated). This removes the vertical streaking.

The contrast and brightness of the image was adjusted, and 'filters' were applied to enhance detail at several scales.

The image was then geometrically warped to meet the computed position information for a mercator-type map. This corrected for the left-right flip, and the non-vertical viewing angle (about 45o from vertical), but also introduced some vertical 'elongation' of the image for the same reason Greenland looks larger than Africa on a mercator map of the Earth.

A section of the image, containing the 'Face' and a couple of nearly impact craters and hills, was 'cut' out of the full image and reproduced separately.

See PIA01440-1442 for additional processing steps. Also see PIA01236 for the raw image.

Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

Polygons on Crater Floor

NASA Technical Reports Server (NTRS)

2003-01-01

MGS MOC Release No. MOC2-357, 11 May 2003

This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) picture shows a pattern of polygons on the floor of a northern plains impact crater. These landforms are common on crater floors at high latitudes on Mars. Similar polygons occur in the arctic and antarctic regions of Earth, where they indicate the presence and freeze-thaw cycling of ground ice. Whether the polygons on Mars also indicate water ice in the ground is uncertain. The image is located in a crater at 64.8oN, 292.7oW. Sunlight illuminates the scene from the lower left.

South Polar Ice Cap

NASA Technical Reports Server (NTRS)

2003-01-01

MGS MOC Release No. MOC2-337, 21 April 2003

This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows the 'swiss cheese' pattern of frozen carbon dioxide on the south polar residual cap. Observation of these materials over two Mars years has revealed that the scarps that bound the mesas and small buttes are retreating-the carbon dioxide ice is subliming away-at a rate of about 3 meters (3 yards) per Mars year in some places. The picture covers an area about 900 m (about 900 yards) wide near 87.1oS, 93.7oW. Sunlight illuminates the scene from the upper left.

Ripple Trap

NASA Image and Video Library

2006-04-03

This Mars Global Surveyor MGS Mars Orbiter Camera MOC image shows the margin of a lava flow on a cratered plain in the Athabasca Vallis region of Mars. Remarkably, the cratered plain in this scene is essentially free of bright, windblown ripples

Polar Cap Pits

NASA Technical Reports Server (NTRS)

2005-01-01

17 August 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows kidney bean-shaped pits, and other pits, formed by erosion in a landscape of frozen carbon dioxide. This images shows one of about a dozen different patterns that are common in various locations across the martian south polar residual cap, an area that has been receiving intense scrutiny by the MGS MOC this year, because it is visible on every orbit and in daylight for most of 2005.

Location near: 86.9oS, 6.9oW Image width: width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Spring

MOC's Highest Resolution View of Mars Pathfinder Landing Site

NASA Technical Reports Server (NTRS)

2000-01-01

[figure removed for brevity, see original site] (A) Mars Pathfinder site, left: April 1998; right: January 2000.

[figure removed for brevity, see original site] (B) top: April 1998; bottom: January 2000.

Can Mars Global Surveyor's 1.5 meter (5 ft) per pixel camera be used to find any evidence as to the fate of the Mars Polar Lander that was lost on December 3, 1999? One way to find out is to look for one of the other Mars landers and determine what, if anything, can be seen. There have been three successful Mars lander missions: Viking 1 (July 1976), Viking 2 (September 1976), and Mars Pathfinder (July 1997). Of these, the location of Mars Pathfinder is known the best because there are several distinct landmarks visible in the lander's images that help in locating the spacecraft. The MGS MOC Operations Team at Malin Space Science Systems has been tasked since mid-December 1999 with looking for the lost Polar Lander. Part of this effort has been to test the capabilities of MOC by taking a picture of the landing site of Mars Pathfinder.

An attempt to photograph the Pathfinder site was made once before, in April 1998, by turning the entire MGS spacecraft so that the camera could point at the known location of the Mars Pathfinder lander. Turning the MGS spacecraft like this is not a normal operation--it takes considerable planning, and disrupts the on-going, normal acquisition of science data. It took 3 attempts to succeed, but on April 22, 1998, MOC acquired the picture seen on the left side of Figure A, above. The three near-by major landmarks that were visible to the Pathfinder's cameras are labeled here (North Peak, Big Crater, Twin Peaks). It was known at the time that this image was not adequate to see the Pathfinder lander because the camera was not in focus and had a resolution of only 3.3 meters (11 ft) per pixel. In this and all other images shown here, north is up. All views of the 1998 MOC image are illuminated from the lower right, all views of the 2000 MOC image are illuminated from the lower left.

As part of the Polar Lander search effort, the Mars Pathfinder site was targeted again in December 1999 and January 2000. Like the 1998 attempt, the spacecraft had to be pointed off of its normal, nadir (straight-down) view. Like history repeating itself, it once again took 3 tries before the Pathfinder landing site was hit. The picture on the right side of Figure A, above, shows the new image that was acquired on January 16, 2000. The white box indicates the location shown in Figure B (above, right). The 1000 m scale bar equals 0.62 miles.

Figure B (above) shows a subsection of both the 1998 image (top, labeled SPO-1-25603) and the 2000 image (bottom, labeled m11-2414) projected at a scale of 3 meters (10 ft) per pixel. At this scale, the differences in camera focus and sunlight illumination angle are apparent, with the January 2000 image being both in focus and having better lighting conditions. In addition, the MGS spacecraft took the 2000 image from a lower altitude than in 1998, thus the image has better spatial resolution overall. The 500 m scale bar is equal to about 547 yards. The white box shows the location of images in Figure C, below.

[figure removed for brevity, see original site] (C) higher-resolution view; left: April 1998; right: January 2000.

[figure removed for brevity, see original site] D) Erroneous, preliminary identification of Mars Pathfinder location in January 2000 image. Subsequent analysis (Figures E & F, below) identified the correct spot.

The third figure (C, above) again shows portions of the April 1998 image (C, left) and January 2000 image (C, right), only this time they have been enlarged to a resolution of 0.75 meters (2.5 ft) per pixel. The intrinsic resolution of the January 2000 image is 1.5 meters (5 ft), so this is a 200% expanded view of the actual M11-02414 image. The circular features in this and the previous images are impact craters in various states of erosion. Some boulders (dark dots) can be seen near the crater in the lower left corner. The texture that runs diagonally across the scene from upper left toward lower right consists of ridges created by the giant floods that washed through the Pathfinder site from Ares and/or Tiu Vallis many hundreds of millions of years ago. These ridges and the troughs between them were also seen by the Pathfinder lander; their crests often covered with boulders and cobbles (which cannot be seen at the resolution of the MOC image). The 100 m scale bar is equal to 109 yards (which can be compared with a 100 yard U.S. football field). The Mars Pathfinder landing site is located near the center of this view.

The fourth picture, Figure D (above), shows a feature that was initially thought to be the Mars Pathfinder lander by MOC investigators. This and the following figures point out just how difficult it is to find a lander on the martian surface using the MGS MOC. Figure D was prepared early in the week following receipt of the new MOC image on January 17, 2000, and for several days it was believed that the lander had been found. As the subsequent two figures will show (E, and F, below), this location appears to be in error. How the features were misidentified is discussed below. Both Figure D and Figure F, showing possible locations of the Pathfinder lander in the MOC image, are enlarged by a factor of three over the intrinsic resolution of that image (that is, to a scale of 0.5 meters or about 1 ft, 7 inch per pixel). The right picture in Figure D shows sight-lines to the large horizon features--Big Crater, Twin Peaks, and North Peak--that were derived by the MOC team by looking at the images taken by the lander in 1997. After placing these lines on the overall image, there appeared to be two features close to the intersection of the sight-lines. Based upon the consistency of the size and shape of the lander as illuminated by sunlight in this image, the northern of the two candidate features (the small 'hump' at the center of both left and right pictures) was considered, at the time, to be the most likely. HOWEVER...

[figure removed for brevity, see original site] (E) Photoclinometry, Topography, and Revised Landing Site Location.

[figure removed for brevity, see original site] (F) Mars Pathfinder Landing Site; lander not resolved by MOC.

Later in the week following acquisition of the January 16, 2000, image (and over the following weekend), there was time for additional analysis to determine whether the rounded hump identified earlier in the week (Figure D, above) was, in fact, the Mars Pathfinder lander. A computer program that estimates relative topography in a MOC image from knowledge of the illumination (called 'shape-from-shading' or photoclinometry) was run to determine which parts of the landing site image are depressions, which are hills, and which are flat surfaces. The picture at the left in Figure E (above) shows the photoclinometry results for the area around the Pathfinder lander. The picture at the center of Figure E shows the same photoclinometry results overlain by an inset of a topographic map of the Pathfinder landing site derived by the U.S. Geological Survey Astrogeology Branch (Flagstaff, Arizona) from photogrammetry (parallax measurements) using images from Pathfinder's own stereo camera. By matching the features seen by MOC with those seen by the Pathfinder (the large arrows are examples of the matching), the location of the lander was refined and is now indicated in the picture on the right side of Figure E. The large, rounded hump previously identified as Pathfinder in Figure D (above), is more likely a large boulder that was seen in Pathfinder's images and named 'Couch' by the Pathfinder science team in 1997.

Figure F is summary of the results of this effort to find Mars Pathfinder: it shows that while the landing site of Mars Pathfinder can be identified, the lander itself cannot be seen. It is too small to be resolved in an image where each pixel acquired by the MOC covers a square of 1.5 meters (5 feet) to a side, given the contrast conditions on Mars and the MOC's ability to discriminate contrast. At this scale, Pathfinder is not much larger than two pixels, and the same is true of the lost Polar Lander.

No evidence has been found in the January 2000 MOC image of the aft portion of Mars Pathfinder's aeroshell or its parachute, either. If the aeroshell is laying on its side, as interpreted from Mars Pathfinder's images, then it would be very difficult to see this from orbit. Because Pathfinder did not image the parachute, it is not known how it may be configured on the surface--it could be wrapped around the aeroshell or a boulder, for example.

This effort to photograph the Mars Pathfinder lander demonstrates that it is extremely difficult to find a lander on the surface of Mars using the Mars Orbiter Camera aboard the MGS spacecraft. This analysis suggests that it is not very likely that the December 1999 Polar Lander will be found by MOC.

Mars Boulders: On a Hill in Utopia Planitia

NASA Image and Video Library

2000-09-18

The Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) was designed specifically to provide images of Mars that have a resolution comparable to the aerial photographs commonly used by Earth scientists to study geological processes and map landforms on our home planet. When MGS reaches its Mapping Orbit in March 1999, MOC will be able to obtain pictures with spatial resolutions of 1.5 meters (5 feet) per pixel--this good enough to easily see objects the size of an automobile. Boulders are one of the keys to determining which processes have eroded, transported, and deposited material on Mars (e.g.,landslides, mud flows, flood debris). During the first year in orbit,MGS MOC obtained pictures with resolutions between 2 and 30 meters (7to 98 feet) per pixel. It was found that boulders are difficult to identify on Mars in images with resolutions worse than about 2-3 meters per pixel. Although not known when the MOC was designed,"thresholds" like this are found on Earth, too. The MOC's 1.5 m/pixel resolution was a compromise between (1) the anticipation of such resolution-dependent sensitivity based on our experience with Earth and (2)the cost in terms of mass if we had built a larger telescope to get a higher resolution. Some rather larger boulders (i.e., larger than about 10 meters--or yards--in size) have already been seen on Mars by the orbiting camera. This is a feat similar to that which can be obtained by "spy" satellites on Earth. The MOC image 53104 subframe shown above features a low, rounded hill in southeastern Utopia Planitia. Each of the small, lumpy features on the top of this hill is a boulder. In this picture, boulders are not seen on the surrounding plain. These boulders are interpreted to be the remnants of a layer of harder rock that once covered the top of the hill, but was subsequently eroded and broken up by weathering and wind processes. MOC image 53104 was taken on September 2, 1998. The subframe shows an area 2.2 km by 3.3 km (1.4 miles by 2.7 miles). The image has a resolution of about 3.25 meters (10.7 feet) per pixel. The subframe is centered at 41.0°N latitude and 207.3°W longitude. North is approximately up, illumination is from the left. http://photojournal.jpl.nasa.gov/catalog/PIA01500

Rocks Exposed on Slope in Aram Chaos

NASA Technical Reports Server (NTRS)

2003-01-01

MGS MOC Release No. MOC2-550, 20 November 2003

This spectacular vista of sedimentary rocks outcropping on a slope in Aram Chaos was acquired by the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) on 14 November 2003. Dark piles of coarse talus have come down the slopes as these materials continue to erode over time. Note that there are no small meteor impact craters in this image, indicating that erosion of these outcrops has been recent, if not on-going. This area is located near 2.8oS, 20.5oW. The 200 meter scale bar is about 656 feet across. Sunlight illuminates the scene from the lower right.

Cycloidal Dust Devil Track

NASA Technical Reports Server (NTRS)

2003-01-01

MGS MOC Release No. MOC2-382, 5 June 2003

The spiraling feature near the center of this Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image is known as a cycloidal marking. Patterns like this can also occur on Earth. On Mars, the cycloidalpattern--and all of the other dark streaks in this picture--are thought to have been formed by passing dust devils. On Earth, cycloidal markings have been observed to result from some tornadoes. The pattern is created when more than one vortex (spinning column of air) is traveling, and spinning, together. This picture is near 62.9oS, 234.7oW. Sunlight illuminates the scene from the upper left.

Defrosting Gully Aprons

NASA Technical Reports Server (NTRS)

2003-01-01

MGS MOC Release No. MOC2-398, 21 June 2003

This is a late winter Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) picture of frost-covered gullies in a crater in the martian southern hemisphere. The dark spots are areas where the frost has begun to change or sublime away. The gullies are formed by a combination of mass movement (landsliding) and possibly fluid flow through the channels--whether the fluid was liquid water or some other material is unknown. Today, the surfaces are dry and subjected to the seasonal coming-and-going of carbon dioxide frost. The image is located near 71.0oS, 95.5oW. Sunlight illuminates the scene from the upper left.

Have a Nice Spring! MOC Revisits "Happy Face" Crater

NASA Image and Video Library

2005-05-16

Smile! Spring has sprung in the martian southern hemisphere. With it comes the annual retreat of the winter polar frost cap. This view of "Happy Face Crater"--officially named "Galle Crater"--shows patches of white water ice frost in and around the crater's south-facing slopes. Slopes that face south will retain frost longer than north-facing slopes because they do not receive as much sunlight in early spring. This picture is a composite of images taken by the Mars Global Surveyor Mars Orbiter Camera (MOC) red and blue wide angle cameras. The wide angle cameras were designed to monitor the changing weather, frost, and wind patterns on Mars. Galle Crater is located on the east rim of the Argyre Basin and is about 215 kilometers (134 miles) across. In this picture, illumination is from the upper left and north is up. http://photojournal.jpl.nasa.gov/catalog/PIA02325

Ophir Landslide

NASA Technical Reports Server (NTRS)

2005-01-01

4 November 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a small landslide off a steep slope in southwestern Ophir Chasma.

Location near: 4.6oS, 72.8oW Image width: width: 3 km (1.9 mi) Illumination from: lower left Season: Southern Spring

A Topographic Image Map of The Mc-18 Quadrangle "coprates" At 1: 2,000,000 Using Data Obtained From The Mars Orbiter Camera and The Mars Orbiter Laser Altimeter of Mars Global Surveyor

NASA Astrophysics Data System (ADS)

Niedermaier, G.; Wählisch, M.; van Gasselt, S.; Scholten, F.; Wewel, F.; Roatsch, T.; Matz, K.-D.; Jaumann, R.

We present a new topographic image map of Mars using 8 bit data obtained from the Mars Orbiter Camera (MOC) of the Mars Global Surveyor (MGS) [1]. The new map covers the Mars surface from 270 E (90 W) to 315 E (45 W) and from 0 North to 30 South with a resolution of 231.529 m/pixel (256 pixel/degree). For map creation, digital image processing methods have been applied. Furthermore, we managed to de- velop a general processing method for creating image mosaics based on MOC data. From a total amount of 66,081 images, 4,835 images (4,339 Context and 496 Geodesy images [3]) were finally used for the creation of the mosaic. After radiometric and brightness corrections, the images were Mars referenced [5], geometrically [6] cor- rected and sinusoidal map projected [4] using a global Martian Digital Terrain Model (DTM), developed by the DLR and based on MGS Mars Orbiter Laser Altimeter (MOLA) topographic datasets [2]. Three layers of MOC mosaics were created, which were stacked afterwards. The upper layer contains the context images with a resolution < 250 m/pixel. The middle layer contains the images of the Geodesy Campaign with a resolution < 250 m/pixel. The bottom layer consists of the Geodesy Campaign im- ages with a resolution > 250 m/pixel and < 435 m/pixel. The contour lines have been extracted from the global Martian DTM, developed at DLR. The contour data were imported as vector data into Macromedia Freehand as separate layer and corrected interactively. The map format of 1,15 m × 1,39 m represents the western part of the MDIM2 j quadrangle. The map is used for geological and morphological interpreta- tions in order to review and improve our current Viking-based knowledge about the Martian surface. References: [1] www.msss.com [2] wufs.wustl.edu [3] Caplinger, M. and M. Malin, The Mars Orbiter Camera Geodesy Campaign, JGR, in press. [4] Scholten, F., Vol XXXI, Part B2, Wien, 1996, p.351-356 [5] naif.jpl.nasa.gov [6] Kirk, R.L. et al., Geometric Calibration of the Mars Orbiter Cameras and Coalignment with Mars Orbiter Laser Altimeter, (abstract #1863), LPSC XXXII, 2001

Circles and Streaks

NASA Technical Reports Server (NTRS)

2003-01-01

MGS MOC Release No. MOC2-544, 14 November 2003

This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image, acquired less than a week ago on 8 November 2003, shows a typical southern middle-to-high latitude scene at this time of year. It is summer in the southern hemisphere, and regions such as Promethei Terra, where this image was acquired, are being streaked by dust devils that remove or disrupt the coating of dust that was deposited over the region in the previous autumn or winter. While no active dust devils were captured in this scene, their tell-tale tracks are scratched all across the image. The circular features are the sites of buried meteor impact craters; their rims form dark rings; the material that fills the craters has become cracked. This picture is located near 68.1oS, 247.9oW. The area shown is approximately 3 km (1.9 mi) across and is illuminated by sunlight from the upper left.

Polygons near Lyot Crater

NASA Technical Reports Server (NTRS)

2003-01-01

MGS MOC Release No. MOC2-564, 4 December 2003

This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows patterned ground, arranged in the form of polygons, on the undulating plains associated with ejecta from the Lyot impact crater on the martian northern plains. This picture was acquired in October 2003 and shows that the polygon margins are ridges with large boulders--shown here as dark dots--on them. On Earth, polygon patterns like this are created in arctic and antarctic regions where there is ice in the ground. The seasonal and longer-term cycles of freezing and thawing of the ice-rich ground cause these features to form over time. Whether the same is true for Mars is unknown. The polygons are located near 54.6oN, 326.6oW. The image covers an area 3 km (1.9 mi) wide and is illuminated from the lower left.

Frosty Wind Streaks

NASA Technical Reports Server (NTRS)

2003-01-01

MGS MOC Release No. MOC2-532, 2 November 2003

As seasonal polar frosts sublime away each spring, winds may re-distribute some of the frost or move sediment exposed from beneath the frost. This action creates ephemeral wind streaks that can be used by scientists seeking to study the local circulation of the martian [missing text] surveyor (MGS) Mars Orbiter Camera (MOC) image shows a suite of wind streaks created in subliming carbon dioxide frost. These dark streaks appear to conform to the shape of the slopes on which they occur, suggesting that slope winds play a dominant role in creating and orienting these streaks. This picture is located near 73.8oS, 305.7oW. The image is illuminated by sunlight from the upper left and covers an area 3 km (1.9 mi) wide. Winds responsible for the streaks generally blew from the bottom/right (south/southeast) toward the top/upper left (north/northwest).

Volcano Near Pavonis Mons

NASA Technical Reports Server (NTRS)

2003-01-01

MGS MOC Release No. MOC2-549, 19 November 2003

The volcanic plains to the east, southeast, and south of the giant Tharsis volcano, Pavonis Mons, are dotted by dozens of small volcanoes. This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows an example located near 2.1oS, 109.1oW. The elongate depression in the lower left (southwest) quarter of the image is the collapsed vent area for this small, unnamed volcano. A slightly sinuous, leveed channel runs from the depression toward the upper right (north-northeast); this is the trace of a collapsed lava tube. The entire scene has been mantled by dust, such that none of the original volcanic rocks are exposed--except minor occurrences on the steepest slopes in the vent area. The scene is 3 km (1.9 mi) wide and illuminated by sunlight from the left/upper left.

Mars Polar Lander: The Search Begins

NASA Technical Reports Server (NTRS)

1999-01-01

[figure removed for brevity, see original site]

Beginning Thursday, December 16, 1999, the Mars Global Surveyor (MGS) spacecraft initiated a search for visible evidence of the fate of the missing Mars Polar Lander using the high resolution Mars Orbiter Camera (MOC) operated by Malin Space Science Systems of San Diego, California. Mars Polar Lander was lost during its landing attempt near 76.3oS, 195.0oW on the martian south polar layered terrain on December 3, 1999. Although the likelihood of seeing the lander is quite small, the MOC effort might provide some clues that shed light on what happened to the lander. The problem, however, is one of 'pixels'--those little square boxes of different shades of gray that comprise a digital image.

The two pictures above illustrate the difficulty of finding the lander in MOC images. The picture at the top of the page is the first of the images that were acquired to look for the lander--this one was snapped by MOC around 3:36 p.m. Greenwich time on December 16th. Local time on Mars was about 2 p.m. Portions of this image are shown at 1/4th scale (left), full-scale (1.5 meters, or 5 feet, per pixel--middle), and 10 times enlarged (right). Because the landing site is very far south (at this latitude on Earth, you would be in Antarctica), the Sun illumination is not ideal for taking high resolution pictures with MOC. Thus, the full-resolution MOC data for this region show a large amount of 'salt and pepper' noise, which arises from statistical fluctuations in how light falling on the MOC charge-coupled-device (CCD) detector is converted to electricity. Other aspects of the MOC electronics also introduce noise. These effects are greatly reduced when taking pictures of portions of Mars that have better, more direct sunlight, or when the images are taken at reduced resolution to, in effect, 'average-out' the noise.

The lower picture shows a model of the Mars Polar Lander sitting on a carpet in a conference room at Malin Space Science Systems. This model is illuminated in the same way that sunlight would illuminate the real lander at 2 p.m. local time in December 1999--in other words, the model is illuminated exactly the way it would be if it occurred in the MOC image shown above (left). This figure shows what the Mars Polar Lander would look like if viewed from above by cameras of different resolutions from 1 centimeter (0.4 inch) per pixel in the upper left to 1.5 meters (5 feet) per pixel in the lower right. The 1.5 meters per pixel view is the best resolution that can be achieved by MOC. Note that at MOC resolution, the lander is just a few pixels across.

The problem of recognizing the lander in MOC images is obvious--all that might be seen is a pattern of a few bright and dark gray pixels. This means that it will be extremely difficult to identify the lander by looking at the relatively noisy MOC images that can be acquired at the landing site--like those shown in the top picture.

How, then, is the MGS MOC team looking for the lander? Primarily, they are looking for associations of features that, together, would suggest whether or not the Mars landing was successful. For example, the parachute that was used to slow the lander from supersonic speeds to just under 300 km/hr (187 mph) was to have been jettisoned, along with part of the aeroshell that protected the lander from the extreme heat of entry, about 40 seconds before landing. The parachute and aeroshell are likely to be within a kilometer (6 tenths of a mile) of the lander. The parachute and aeroshell are nearly white, so they should stand out well against the red martian soil. The parachute, if lying on the ground in a fully open, flat position, would measure about 6 meters (20 feet)--thus it would cover three or four pixels (at most) in a MOC image. If the parachute can be found, the search for the lander can be narrowed to a small, nearby zone. If, as another example, the landing rockets kicked up a lot of dust and roughened the surface around the lander, evidence for this might show up as a dark circle surrounding a bright pixel (part of the lander) in the middle. The MOC operations team is using a set of these and similar scenarios to guide the examination of these images. The search continues...

1.5 Meter Per Pixel View of Boulders in Ganges Chasma

NASA Technical Reports Server (NTRS)

1999-01-01

The Mars Orbiter Camera (MOC) on board the Mars Global Surveyor (MGS)spacecraft was designed to be able to take pictures that 'bridge the gap' between what could be seen by the Mariner 9 and Viking Orbiters from space and what could be seen by landers from the ground. In other words, MOC was designed to be able to see boulders of sizes similar to and larger than those named 'Yogi' at the Mars Pathfinder site and 'Big Joe' at the Viking 1 landing site. To see such boulders, a resolution of at least 1.5 meters (5 feet) per pixel was required.

With the start of the MGS Mapping Phase of the mission during the second week of March 1999, the MOC team is pleased to report that 'the gap is bridged.' This image shows a field of boulders on the surface of a landslide deposit in Ganges Chasma. Ganges Chasma is one of the valleys in the Valles Marineris canyon system. The image resolution is 1.5 meters per pixel. The boulders shown here range in size from about 2 meters (7 feet) to about 20 meters (66 feet) in size. The image covers an area 1 kilometer (0.62 miles) across, and illumination is from the upper left.

Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

Tithonium Landslide

NASA Technical Reports Server (NTRS)

2006-01-01

12 February 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a portion of a large landslide deposit on the floor of western Tithonium Chasma.

Location near: 4.3oS, 87.9oW Image width: 3 km (1.9 mi) Illumination from: lower left Season: Southern Summer

South Polar Cap

NASA Technical Reports Server (NTRS)

2005-01-01

17 March 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows mesas and pits formed by sublimation of carbon dioxide of the south polar cap.

Location near: 85.8oS, 351.5oW Image width: 2 km (1.2 mi) Illumination from: upper left Season: Southern Summer

Ripples and Rocks

NASA Technical Reports Server (NTRS)

2005-01-01

26 February 2005 This Mars Global Surveyor (MGS) Orbiter Camera (MOC) image shows light-toned sedimentary rock outcrops and large dark-toned, windblown ripples in Aram Chaos.

Location near: 3.0oN, 20.9oW Image width: 3 km (1.9 mi) Illumination from: upper left Season: Northern Summer

Mars Orbiter Camera Acquires High Resolution Stereoscopic Images of the Viking One Landing Site

NASA Technical Reports Server (NTRS)

1998-01-01

Two MOC images of the vicinity of the Viking Lander 1 (MOC 23503 and 25403), acquired separately on 12 April 1998 at 08:32 PDT and 21 April 1998 at 13:54 PDT (respectively), are combined here in a stereoscopic anaglyph. The more recent, slightly better quality image is in the red channel, while the earlier image is shown in the blue and green channels. Only the overlap portion of the images is included in the composite.

Image 23503 was taken at a viewing angle of 31.6o from vertical; 25403 was taken at an angle of 22.4o, for a difference of 9.4o. Although this is not as large a difference as is typically used in stereo mapping, it is sufficient to provide some indication of relief, at least in locations of high relief.

The image shows the raised rims and deep interiors of the larger impact craters in the area (the largest crater is about 650 m/2100 feet across). It shows that the relief on the ridges is very subtle, and that, in general, the Viking landing site is very flat. This result is, of course, expected: the VL-1 site was chosen specifically because it was likely to have low to very low slopes that represented potential hazards to the spacecraft.

Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

Mesa = Table

NASA Technical Reports Server (NTRS)

2006-01-01

10 August 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows two mesas on the northern plains of Mars. 'Mesa' is the Spanish word for 'table,' and that is a very good description of the two elliptical features captured in this MOC image. In both cases, the mesa tops and the material beneath them, down to the level of the surrounding, rugged plain, are remnants of a once more extensive layer (or layers) of material that has been largely eroded away. The circular feature near the center of the larger mesa is the site of a filled and buried impact crater.

Location near: 53.5oN, 153.5oW Image width: 3 km (1.9 mi) Illumination from: lower left Season: Northern Spring

South Melea Planum, By The Dawn's Early Light

NASA Technical Reports Server (NTRS)

1999-01-01

MOC 'sees' by the dawn's early light! This picture was taken over the high southern polar latitudes during the first week of May 1999. The area shown is currently in southern winter darkness. Because sunlight is scattered over the horizon by aerosols--dust and ice particles--suspended in the atmosphere, sufficient light reaches regions within a few degrees of the terminator (the line dividing night and day) to be visible to the Mars Global Surveyor Mars Orbiter Camera (MOC) when the maximum exposure settings are used.

This image shows a bright, wispy cloud hanging over southern Malea Planum. This cloud would not normally be visible, since it is currently in darkness. At the time this picture was taken, the sun was more than 5.7o below the northern horizon. The scene covers an area 3 kilometers (1.9 miles) wide. Again, the illumination is from the top.

In this frame, the surface appears a relatively uniform gray. At the time the picture was acquired, the surface was covered with south polar wintertime frost. The highly reflective frost, in fact, may have contributed to the increased visibility of this surface.

This 'twilight imaging' technique for viewing Mars can only work near the terminator; thus in early May only regions between about 67oS and 74oS were visible in twilight images in the southern hemisphere, and a similar narrow latitude range could be imaged in the northern hemisphere. MOC cannot 'see' in the total darkness of full-borne night.

Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

Polar Polygons

NASA Technical Reports Server (NTRS)

2005-01-01

13 February 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows polygons formed in ice-rich material in the north polar region of Mars. The bright surfaces in this image are covered by a thin water ice frost.

Location near: 79.8oN, 344.8oW Image width: 1.5 km (1.9 mi) Illumination from: lower left Season: Northern Summer

Ganges Landslides

NASA Technical Reports Server (NTRS)

2005-01-01

This Mars Global Surveyor (MGS) Orbiter Camera (MOC) image shows a high resolution view of portions of the lobes of several landslide deposits in Ganges Chasma. Dark material near the bottom (south) end of the image is windblown sand.

Location near: 8.2oS, 44.3oW Image width: 3.0 km (1.9 mi) Illumination from: upper left Season: Southern Winter

Dust Devil Art

NASA Technical Reports Server (NTRS)

2003-01-01

MGS MOC Release No. MOC2-541, 11 November 2003

In some regions of Mars, dust devils create streaks by disrupting or removing thin coatings of fine, bright dust from the surface. This summertime view of terrain in southern Noachis Terra, acquired by the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC), provides an example. Streak patterns such as these are commonly created during the spring and summer in the southern hemisphere; in autumn and winter they are often erased--perhaps by deposition of a new coating of dust--and then a completely different pattern is formed the following spring and summer. This image is located near 59.6oS, 328.8oW. The picture is 3 km (1.9 mi) wide and illuminated by sunlight from the upper left.

Summertime Dust Devil

NASA Technical Reports Server (NTRS)

2003-01-01

MGS MOC Release No. MOC2-464, 26 August 2003

Dust devils are spinning, columnar vortices of air that move across a landscape, picking up dust as they go. They are common occurrences during summer on Mars. This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image, acquired during northern summer, shows a dust devil in the Phlegra region of Mars near 32.0oN, 182.1oW. Sunlight illuminates the scene from the lower left; the dust devil is casting a columnar shadow toward the upper right. Some dust devils on Mars make streaks as they disrupt the fine coating of dust on the surface--but others do not make streaks. This one did not make a streak. The view shown here is 3 km (1.9 mi) wide.

South Polar Artwork

NASA Technical Reports Server (NTRS)

2003-01-01

MGS MOC Release No. MOC2-456, 18 August 2003

Nature has created some interesting artwork on the south polar residual cap of Mars. This July 2003 Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows an example. The patterns in this picture are formed by erosion and sublimation of multiple layers of frozen carbon dioxide. The artwork is ephemeral and changing with each passing summer. By the end of the coming southern summer, the scarps in this area will have retreated an average of 3 meters (3.3 yards); some of the smaller buttes and ridges will have vanished. This picture covers an area 3 km (1.9 mi) wide and is located near 86.6oS, 358.2oW. Sunlight illuminates the scene from the upper left.

The Australian Paleoflood Model for Unconfined Fluvial Deposition on Mars

NASA Technical Reports Server (NTRS)

Bourke, M. C.; Zimbelman, J. R.

2001-01-01

Paleoflood deposits in central Australia represent a new model for possible fluvial deposits on Mars. The distinct Australian assemblage of landforms and sediments is used to identify potential unconfined paleoflood deposits in Mars Orbiter Camera (MOC) images of Mars. Additional information is contained in the original extended abstract.

Mars at Ls 341o: Acidalia/Mare Erythraeum

NASA Technical Reports Server (NTRS)

2005-01-01

13 December 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a banded surface in Argyre Planitia, the second largest impact basin in the martian southern hemisphere. The bands are the erosional expression of layered, perhaps sedimentary, rock.

Season: Northern Winter/Southern Summer

Exhuming Crater in Northeast Arabia

NASA Technical Reports Server (NTRS)

2003-01-01

MGS MOC Release No. MOC2-563, 3 December 2003

The upper crust of Mars is layered, and interbedded with these layers are old, filled and buried meteor impact craters. In a few places on Mars, such as Arabia Terra, erosion has re-exposed some of the filled and buried craters. This October 2003 Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows an example. The larger circular feature was once a meteor crater. It was filled with sediment, then buried beneath younger rocks. The smaller circular feature is a younger impact crater that formed in the surface above the rocks that buried the large crater. Later, erosion removed all of the material that covered the larger, buried crater, except in the location of the small crater. This pair of martian landforms is located near 17.6oN, 312.8oW. The image covers an area 3 km (1.9 mi) wide and is illuminated from the lower left.

Martian Mystery: Do Some Materials Flow Uphill?

NASA Technical Reports Server (NTRS)

1999-01-01

Some of the geological features of Mars defy conventional, or simple, explanations. A recent example is on the wall of a 72 kilometer-wide (45 mile-wide) impact crater in Promethei Terra. The crater (above left) is located at 39oS, 247oW. Its inner walls appear in low-resolution images to be deeply gullied.

A high resolution Mars Orbiter Camera (MOC) image shows that each gully on the crater's inner wall contains a tongue of material that appears to have flowed (to best see this, click on the icon above right and examine the full image). Ridges and grooves that converge toward the center of each gully and show a pronounced curvature are oriented in a manner that seems to suggest that material has flowed from the top toward the bottom of the picture. This pattern is not unlike pouring pancake batter into a pan... the viscous fluid will form a steep, lobate margin and spread outward across the pan. The ridges and grooves seen in the image are also more reminiscent of the movement of material out and away from a place of confinement, as opposed to the types of features seen when they flow into a more confined area. Mud and lava-flows, and even some glaciers, for the most part behave in this manner. From these observations, and based solely on the appearance, one might conclude that the features formed by moving from the top of the image towards the bottom.

But this is not the case! The material cannot have flowed from the top towards the bottom of the area seen in the high resolution image (above, right), because the crater floor (which is the lowest area in the image) is at the top of the picture. The location and correct orientation of the high resolution image is shown by a white box in the context frame on the left. Since gravity pulls the material in the gullies downhill not uphill the pattern of ridges and grooves found on these gully-filling materials is puzzling. An explanation may lie in the nature of the material (e.g., how viscous was the pancake batter-like material?) and how rapidly it moved, but for now this remains an unexplained martian phenomenon.

The context image (above, left) was taken by the MOC red wide angle camera at the same time that the MOC narrow angle camera obtained the high resolution view (above, right). Context images such as this provide a simple way to determine the location of each new high resolution view of the planet. Both images are illuminated from the upper left. The high resolution image covers an area 3 km (1.9 mi) across.

Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

Dust Devil Tracks and Wind Streaks in the North Polar Region of Mars: A Study of the 2007 Phoenix Mars Lander Sites

NASA Technical Reports Server (NTRS)

Drake, Nathan B.; Tamppari, Leslie K.; Baker, R. David; Cantor, Bruce A.; Hale, Amy S.

2006-01-01

The 65-72 latitude band of the North Polar Region of Mars, where the 2007 Phoenix Mars Lander will land, was studied using satellite images from the Mars Global Surveyor (MGS) Mars Orbiter Camera Narrow-Angle (MOC-NA) camera. Dust devil tracks (DDT) and wind streaks (WS) were observed and recorded as surface evidence for winds. No active dust devils (DDs) were observed. 162 MOC-NA images, 10.3% of total images, contained DDT/WS. Phoenix landing Region C (295-315W) had the highest concentration of images containing DDT/WS per number of available images (20.9%); Region D (130-150W) had the lowest (3.5%). DDT and WS direction were recorded for Phoenix landing regions A (110-130W), B (240-260W), and C to infer local wind direction. Region A showed dominant northwest-southeast DDT/WS, Region B showed dominant north-south, east-west and northeast-southwest DDT/WS, and region C showed dominant west/northwest - east/southeast DDT/ WS. Results indicate the 2007 Phoenix Lander has the highest probability of landing near DDT/WS in landing Region C. Based on DDT/WS linearity, we infer Phoenix would likely encounter directionally consistent background wind in any of the three regions.

Cerberus Flood Features

NASA Technical Reports Server (NTRS)

2005-01-01

16 October 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows streamlined landforms carved by catastrophic floods that occurred in the eastern Cerberus region, some time in the distant martian past.

Location near: 15.1oN, 193.5oW Image width: width: 3 km (1.9 mi) Illumination from: lower left Season: Northern Autumn

Dust Devil Art

NASA Technical Reports Server (NTRS)

2005-01-01

12 December 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows dark squiggles and streaks created by passing spring and summer dust devils near Pallacopas Vallis in the martian southern hemisphere.

Location near: 53.9oS, 17.2oW Image width: width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Summer

Copernicus Dunes

NASA Technical Reports Server (NTRS)

2005-01-01

22 December 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows dark teardrop-shaped sand dunes in eastern Copernicus Crater. The winds responsible for these dunes generally blow from the south-southwest (lower left).

Location near: 48.7oS, 167.4oW Image width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Summer

Northeast Isidis

NASA Technical Reports Server (NTRS)

2005-01-01

7 December 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a mesa in northeastern Isidis Planitia. The mesa might be a remnant of terrain that once more extensively covered the region.

Location near: 20.3oN, 267.7oW Image width: width: 3 km (1.9 mi) Illumination from: lower left Season: Northern Winter

Ripple Belt

NASA Technical Reports Server (NTRS)

2006-01-01

16 July 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows windblown materials that have collected and been shaped into large ripples in a valley in the Auqakuh Vallis system in northeastern Arabia Terra, Mars.

Location near: 29.1oN, 299.6oW Image width: 2 km (1.2 mi) Illumination from: lower left Season: Northern Winter

Frost on Dunes

NASA Technical Reports Server (NTRS)

2005-01-01

18 March 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows dark dunes on a crater floor during the southern spring. Some of the dunes have frost on their south-facing slopes.

Location near: 52.3oS, 326.7oW Image width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Spring

Kidney-Shaped Impact

NASA Technical Reports Server (NTRS)

2006-01-01

23 February 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows an unusally-shaped (not circular) impact crater in the Elysium region of Mars. A dark-toned lava flow surface is seen in the southern (lower) portion of the image.

Location near: 5.9oN, 220.0oW Image width: 3 km (1.9 mi) Illumination from: lower left Season: Northern Winter

Landslide!

NASA Technical Reports Server (NTRS)

2003-01-01

MGS MOC Release No. MOC2-486, 17 September 2003

This August 2003 Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows part of a deposit created by a landslide off the wall of a crater near 12.3oN, 21.3oW. The crater wall is not shown; it is several kilometers to the left of this picture. The debris that slid from the crater wall came from the left/upper left (northwest) and moved toward the lower right (southeast). The crater floor onto which the debris was deposited has more small meteor craters on it than does the landslide material; this indicates that there was a considerable interval between the time when the crater floor formed, and when the landslide occurred. This picture covers an area 3 km (1.9 mi) wide. Sunlight illuminates the scene from the lower left.

Geologic Mapping of Athabasca Valles

NASA Technical Reports Server (NTRS)

Keszthelyi, L. P.; Jaeger, W. L.; Tanaka, K.; Hare, T.

2008-01-01

Two factors drive us to map the Athabasca Valles area in unusual detail: (1) the extremely well-preserved and exposed surface morphologies and (2) the extensive high resolution imaging. In particular, the near-complete CTX coverage of Athabasca Valles proper and the extensive coverage of its surroundings have been invaluable. The mapping has been done exclusively in ArcGIS, using individual CTX, THEMIS VIS, and MOC frames overlying the THEMIS IR daytime basemap. MOLA shot points and gridded DTMs are also included. It was found that CTX images processed through ISIS are almost always within 300 m of the MOLA derived locations, and usually within tens of meters, with no adjustments to camera pointing. THEMIS VIS images appear to be systematically shifted to the southwest of their correct positions and MOC images are often kilometers off. The good SNR and minimal artifacts make the CTX images vastly more useful than the THEMIS VIS or MOC images. The bulk of the mapping was done at 1:50,000 scale on CTX images. In more complex areas, mapping at 1:24,000 proved necessary. The CTX images were usually simultaneously viewed on a second monitor using the ISIS3 qview program to display the full dynamic range of the CTX data. Where CTX data was not available, mapping was often done at 1:100,000 and most contacts are mapped as approximate.

South Melea Planum, By The Dawn's Early Light

NASA Technical Reports Server (NTRS)

1999-01-01

MOC 'sees' by the dawn's early light! This picture was taken over the high southern polar latitudes during the first week of May 1999. The area shown is currently in southern winter darkness. Because sunlight is scattered over the horizon by aerosols--dust and ice particles--suspended in the atmosphere, sufficient light reaches regions within a few degrees of the terminator (the line dividing night and day) to be visible to the Mars Global Surveyor Mars Orbiter Camera (MOC) when the maximum exposure settings are used.

This picture shows a polygonally-patterned surface on southern Malea Planum. At the time the picture was taken, the sun was more than 4.5o below the northern horizon. The scene covers an area 3 kilometers (1.9 miles) wide, with the illumination from the top of the picture.

In this frame, the surface appears a relatively uniform gray. At the time the picture was acquired, the surface was covered with south polar wintertime frost. The highly reflective frost, in fact, may have contributed to the increased visibility of this surface.

This 'twilight imaging' technique for viewing Mars can only work near the terminator; thus in early May only regions between about 67oS and 74oS were visible in twilight images in the southern hemisphere, and a similar narrow latitude range could be imaged in the northern hemisphere. MOC cannot 'see' in the total darkness of full-borne night.

Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

Arsia Mons Spiral Cloud

NASA Technical Reports Server (NTRS)

2002-01-01

One of the benefits of the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) Extended Mission is the opportunity to observe how the planet's weather changes during a second full martian year. This picture of Arsia Mons was taken June 19, 2001; southern spring equinox occurred the same day. Arsia Mons is a volcano nearly large enough to cover the state of New Mexico. On this particular day (the first day of Spring), the MOC wide angle cameras documented an unusual spiral-shaped cloud within the 110 km (68 mi) diameter caldera--the summit crater--of the giant volcano. Because the cloud is bright both in the red and blue images acquired by the wide angle cameras, it probably consisted mostly of fine dust grains. The cloud's spin may have been induced by winds off the inner slopes of the volcano's caldera walls resulting from the temperature differences between the walls and the caldera floor, or by a vortex as winds blew up and over the caldera. Similar spiral clouds were seen inside the caldera for several days; we don't know if this was a single cloud that persisted throughout that time or one that regenerated each afternoon. Sunlight illuminates this scene from the left/upper left.

Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

Electric Polygons

NASA Technical Reports Server (NTRS)

2006-01-01

14 July 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows erosional remnants of layered rock and large windblown ripples on the floor of a crater in the Tyrrhena Terra region of Mars. The layered rocks are most likely sedimentary.

Location near: 68.5oN, 191.8oW Image width: 3 km (1.9 mi) Illumination from: lower left Season: Northern Spring

Arsinoes Chaos Landforms

NASA Technical Reports Server (NTRS)

2004-01-01

23 October 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows light-toned rock outcrops, possibly sedimentary rocks, in the Arsinoes Chaos region east of the Valles Marineris trough system. These rocky materials were once below the martian surface. These features are located near 7.2oS, 27.9oW. The image covers an area about 3 km (1.9 mi) wide. Sunlight illuminates the scene from the upper left.

Aram Chaos Rocks

NASA Technical Reports Server (NTRS)

2005-01-01

8 September 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows outcrops of light-toned, sedimentary rock among darker-toned mesas in Aram Chaos. Dark, windblown megaripples -- large ripples -- are also present at this location.

Location near: 3.0oN, 21.6oW Image width: width: 3 km (1.9 mi) Illumination from: lower left Season: Northern Autumn

Carbon Dioxide Landscape

NASA Technical Reports Server (NTRS)

2004-01-01

7 July 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a mid-summer view of the south polar residual cap at full MOC resolution, 1.5 m (5 ft) per pixel. During each of the three summers since the start of the MGS mapping mission in March 1999, the scarps that form mesas and pits in the 'Swiss cheese'-like south polar terrain have retreated an average of about 3 meters (1 yard). The material is frozen carbon dioxide; another 3 meters or so of each scarp is expected to be removed during the next summer, in late 2005. This image is located near 86.0oS, 350.8oW, and covers an area about 1.5 km (0.9 mi) wide. Sunlight illuminates the scene from the top/upper left.

Earth and Moon as viewed from Mars

NASA Technical Reports Server (NTRS)

2003-01-01

MGS MOC Release No. MOC2-368, 22 May 2003

[figure removed for brevity, see original site] Globe diagram illustrates the Earth's orientation as viewed from Mars (North and South America were in view).

Earth/Moon: This is the first image of Earth ever taken from another planet that actually shows our home as a planetary disk. Because Earth and the Moon are closer to the Sun than Mars, they exhibit phases, just as the Moon, Venus, and Mercury do when viewed from Earth. As seen from Mars by MGS on 8 May 2003 at 13:00 GMT (6:00 AM PDT), Earth and the Moon appeared in the evening sky. The MOC Earth/Moon image has been specially processed to allow both Earth (with an apparent magnitude of -2.5) and the much darker Moon (with an apparent magnitude of +0.9) to be visible together. The bright area at the top of the image of Earth is cloud cover over central and eastern North America. Below that, a darker area includes Central America and the Gulf of Mexico. The bright feature near the center-right of the crescent Earth consists of clouds over northern South America. The image also shows the Earth-facing hemisphere of the Moon, since the Moon was on the far side of Earth as viewed from Mars. The slightly lighter tone of the lower portion of the image of the Moon results from the large and conspicuous ray system associated with the crater Tycho.

A note about the coloring process: The MGS MOC high resolution camera only takes grayscale (black-and-white) images. To 'colorize' the image, a Mariner 10 Earth/Moon image taken in 1973 was used to color the MOC Earth and Moon picture. The procedure used was as follows: the Mariner 10 image was converted from 24-bit color to 8-bit color using a JPEG to GIF conversion program. The 8-bit color image was converted to 8-bit grayscale and an associated lookup table mapping each gray value of the image to a red-green-blue color triplet (RGB). Each color triplet was root-sum-squared (RSS), and sorted in increasing RSS value. These sorted lists were brightness-to-color maps for the images. Each brightness-to-color map was then used to convert the 8-bit grayscale MOC image to an 8-bit color image. This 8-bit color image was then converted to a 24-bit color image. The color image was edited to return the background to black.

Albedo Boundary

NASA Technical Reports Server (NTRS)

2003-01-01

MGS MOC Release No. MOC2-510, 11 October 2003

The sharp, nearly straight line that runs diagonally across the center of this April 2003 Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image is an albedo boundary. Albedois a term that refers to reflectance of sunlight. A surface with a low albedo is one that appears dark because it reflects less light than a high albedo (bright) surface. On Mars, albedo boundaries occur between two materials of differing texture, particle size, or composition, or some combination of these three factors. The boundary shown here is remarkable because it is so sharp and straight. This is caused by wind. Most likely, the entire surface was once covered with the lower-albedo (darker) material that is now seen in the upper half of the image. At some later time, wind stripped away this darker material from the surfaces in the lower half of the image. The difference in albedo here might be related to composition, and possibly particle size. This picture is located near the southwest rim of Schiaparelli Basin at 5.5oS, 345.9oW. The picture covers an area 3 km (1.9 mi) wide and is illuminated by sunlight from the left.

Frozen Carbon Dioxide

NASA Technical Reports Server (NTRS)

2005-01-01

1 August 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a south polar residual cap landscape, formed in frozen carbon dioxide. There is no place on Earth that one can go to visit a landscape covering thousands of square kilometers with frozen carbon dioxide, so mesas, pits, and other landforms of the martian south polar region are as alien as they are beautiful. The scarps of the south polar region are known from thousands of other MGS MOC images to retreat at a rate of about 3 meters (3 yards) per martian year, indiating that slowly, over the course of the MGS mission, the amount of carbon dioxide in the martian atmosphere has probably been increasing.

Location near: 86.9oS, 25.5oW Image width: width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Spring

Marte Vallis Platy Flows

NASA Technical Reports Server (NTRS)

2003-01-01

MGS MOC Release No. MOC2-442, 4 August 2003

The Marte Vallis system, located east of Cerberus and west of Amazonis Planitia, is known for its array of broken, platy flow features. This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a close-up view of some of these plates; they appear to be like puzzle pieces that have been broken apart and moved away from each other. The Mars science community has been discussing these features for the past several years--either the flows in Marte Vallis are lava flows, or mud flows. In either case, the material was very fluid and had a thin crust on its surface. As the material continued to flow through the valley system, the crust broke up into smaller plates that were then rafted some distance down the valley. This picture is located near 6.9oN, 182.8oW. It is illuminated by sunlight from the left.

Spiders from Mars?

NASA Technical Reports Server (NTRS)

2003-01-01

MGS MOC Release No. MOC2-426, 19 July 2003

No, this is not a picture of a giant, martian spider web. This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a plethora of polygonal features on the floor of a northern hemisphere impact crater near 65.6oN, 327.7oW. The picture was acquired during spring, after the seasonal carbon dioxide frost cap had largely migrated through the region. At the time the picture was taken, remnants of seasonal frost remained on the crater rim and on the edges of the troughs that bound each of the polygons. Frost often provides a helpful hint as to where polygons and patterned ground occur. The polygons, if they were on Earth, would indicate the presence of freeze-thaw cycles in ground ice. Although uncertain, the same might be true of Mars. Sunlight illuminates the scene from the lower left.

Boulder Track

NASA Technical Reports Server (NTRS)

2003-01-01

MGS MOC Release No. MOC2-408, 1 July 2003

If a boulder rolls down a slope on an uninhabited planet, does it make a sound? While we do not know the sound made by a boulder rolling down a slope in the martian region of Gordii Dorsum, we do know that it made an impression. This full-resolution Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a series of depressions made on a dust-mantled slope as a boulder rolled down it, sometime in the recent past. The boulder track is located just right of center in this picture. The boulder sits at the end of the track. This picture was acquired in May 2003; it is located near 11.2oN, 147.8oW. North is toward the lower left, sunlight illuminates the scene from the right. The picture covers an area only 810 meters (about 886 yards) across.

South Polar Variety

NASA Technical Reports Server (NTRS)

2005-01-01

28 July 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a view of linear troughs and mesas formed in the frozen carbon dioxide of the martian south polar residual cap. This image, obtained in May 2005, is a reminder that not all of the south polar cap landscapes resemble 'swiss cheese.'

Location near: 86.7oS, 24.8oW Image width: width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Spring

Enhanced by Frost

NASA Technical Reports Server (NTRS)

2005-01-01

30 September 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows outcrops of south polar layered terrain. Their appearance in this July 2005 springtime image is enhanced by bright patches of carbon dioxide frost. The frost is left over from the previous southern winter season; by summer, the frost would be gone.

Location near: 84.6oS, 203.5oW Image width: width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Spring

South Polar Polygons

NASA Technical Reports Server (NTRS)

2005-01-01

4 July 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a polgyon-cracked surface, into which deep, somewhat kidney-bean-shaped pits have formed. These are landscapes of the martian south polar residual cap. This view was captured during May 2005.

Location near: 86.9oS, 5.1oW Image width: 1.5 km (0.9 mi) Illumination from: upper left Season Southern Spring

Wind-Eroded Landscape

NASA Technical Reports Server (NTRS)

2005-01-01

5 August 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a dust-mantled, wind-eroded landscape in the Medusae Sulci region of Mars. Wind eroded the bedrock in this region, and then, later, windblown dust covered much of the terrain.

Location near: 5.7oS, 160.2oW Image width: width: 3 km (1.9 mi) Illumination from: lower left Season: Southern Spring

South Polar Cap

NASA Technical Reports Server (NTRS)

2005-01-01

8 December 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows landforms created by sublimation processes on the south polar residual cap of Mars. The bulk of the ice in the south polar residual cap is frozen carbon dioxide.

Location near: 86.6oS, 342.2oW Image width: width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Summer

Mesa with Apron

NASA Technical Reports Server (NTRS)

2006-01-01

23 September 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a mesa and an impact grater just east of Phlegra Montes. The mesa is the eroded remnant of a once more extensive terrain. An apron of material surrounds the mesa.

Location near: 38.5oN, 193.4oW Image width: 3 km (1.9 mi) Illumination from: lower left Season: Northern Spring

Mars Orbiter Camera Views the 'Face on Mars' - Best View from Viking

NASA Technical Reports Server (NTRS)

1998-01-01

Shortly after midnight Sunday morning (5 April 1998 12:39 AM PST), the Mars Orbiter Camera (MOC) on the Mars Global Surveyor (MGS) spacecraft successfully acquired a high resolution image of the 'Face on Mars' feature in the Cydonia region. The image was transmitted to Earth on Sunday, and retrieved from the mission computer data base Monday morning (6 April 1998). The image was processed at the Malin Space Science Systems (MSSS) facility 9:15 AM and the raw image immediately transferred to the Jet Propulsion Laboratory (JPL) for release to the Internet. The images shown here were subsequently processed at MSSS.

The picture was acquired 375 seconds after the spacecraft's 220th close approach to Mars. At that time, the 'Face', located at approximately 40.8o N, 9.6o W, was 275 miles (444 km) from the spacecraft. The 'morning' sun was 25o above the horizon. The picture has a resolution of 14.1 feet (4.3 meters) per pixel, making it ten times higher resolution than the best previous image of the feature, which was taken by the Viking Mission in the mid-1970's. The full image covers an area 2.7 miles (4.4 km) wide and 25.7 miles (41.5 km) long.

This Viking Orbiter image is one of the best Viking pictures of the area Cydonia where the 'Face' is located. Marked on the image are the 'footprint' of the high resolution (narrow angle) Mars Orbiter Camera image and the area seen in enlarged views (dashed box). See PIA01440-1442 for these images in raw and processed form.

Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

Content Based Image Matching for Planetary Science

NASA Astrophysics Data System (ADS)

Deans, M. C.; Meyer, C.

2006-12-01

Planetary missions generate large volumes of data. With the MER rovers still functioning on Mars, PDS contains over 7200 released images from the Microscopic Imagers alone. These data products are only searchable by keys such as the Sol, spacecraft clock, or rover motion counter index, with little connection to the semantic content of the images. We have developed a method for matching images based on the visual textures in images. For every image in a database, a series of filters compute the image response to localized frequencies and orientations. Filter responses are turned into a low dimensional descriptor vector, generating a 37 dimensional fingerprint. For images such as the MER MI, this represents a compression ratio of 99.9965% (the fingerprint is approximately 0.0035% the size of the original image). At query time, fingerprints are quickly matched to find images with similar appearance. Image databases containing several thousand images are preprocessed offline in a matter of hours. Image matches from the database are found in a matter of seconds. We have demonstrated this image matching technique using three sources of data. The first database consists of 7200 images from the MER Microscopic Imager. The second database consists of 3500 images from the Narrow Angle Mars Orbital Camera (MOC-NA), which were cropped into 1024×1024 sub-images for consistency. The third database consists of 7500 scanned archival photos from the Apollo Metric Camera. Example query results from all three data sources are shown. We have also carried out user tests to evaluate matching performance by hand labeling results. User tests verify approximately 20% false positive rate for the top 14 results for MOC NA and MER MI data. This means typically 10 to 12 results out of 14 match the query image sufficiently. This represents a powerful search tool for databases of thousands of images where the a priori match probability for an image might be less than 1%. Qualitatively, correct matches can also be confirmed by verifying MI images taken in the same z-stack, or MOC image tiles taken from the same image strip. False negatives are difficult to quantify as it would mean finding matches in the database of thousands of images that the algorithm did not detect.

Possible Rootless Cones or Pseudo craters on Mars

NASA Technical Reports Server (NTRS)

1999-01-01

High-resolution images from the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) have revealed small cone-shaped structures on lava flows in southern Elysium Planitia, Marte Valles, and northwestern Amazonis Planitia in the northern hemisphere of the red planet. The most likely interpretation of these cones is that they may be volcanic features known as 'pseudo craters' or 'rootless cones.' They share several key characteristics with pseudo craters on Earth: they are distributed in small clusters independent of structural patterns, are superimposed on fresh lava flows, and they do not appear to have erupted lavas themselves. The white box in the picture above left shows the location of one of the MOC images of possible pseudocraters on Mars. The white box is drawn upon a MOC red wide angle context image acquired at the same time as the high resolution view, shown on the right above. Located in northwestern Amazonis Planitia near 24.8oN, 171.3oW, both the context image and high-resolution view are illuminated from the lower left. The high resolution view shows several possible pseudocraters (cone-shaped features with holes or pits at their summits) that occur on top of a rough-textured lava plain. The context frame covers an area 115 km (71 mi) across, the high-resolution view is 3 km (1.9 mi) across. Pseudocraters form by explosions due to the interaction of molten lava with a water-rich surface. Possible martian pseudocraters are of interest because they may mark the locations of shallow water or ice at the time the lava was emplaced. Viking Orbiter images have shown structures in other regions of Mars that were interpreted to be pseudocraters, but the interpretations were uncertain because the morphology was poorly resolved, it was unclear if they occurred on volcanic surfaces, and they have diameters as much as a factor of 3 larger than terrestrial pseudocraters. The cone-shaped morphology is well resolved in the cones imaged by MOC, and they have basal diameters of less than 250 m (273 yards), consistent with terrestrial examples. The cones rest on a surface with a distinctive morphology consisting of ridged plates that have rafted apart, which MOC team members have interpreted as the surface of voluminous lava flows. The surface shown here (above right) looks relatively fresh and has very few impact craters on it, which suggests that the lava flows and the cones are both geologically young. However, MOC images in other areas reveal such apparently young surfaces being exhumed (presumably by wind erosion) from beneath a blanket of overlying material. Impact processes may harden the blanket, or cover it with materials that cannot be removed by wind, so the wind erosion leaves behind elevated 'pedestalcraters.' The cones shown here are not typical of pedestal craters, but it is important to consider this alternative interpretation. MGS MOC first began taking pictures of Mars in mid-September 1997. The planet that has been revealed by this camera is often strange, new, and exciting. The possibility that lava and water or ice have interacted to create features like pseudocraters indicates that Mars has had a diverse and complex past that researchers are only just beginning to understand.

MOC Image of Phobos with TES Temperature Overlay

NASA Technical Reports Server (NTRS)

1998-01-01

This image of Phobos, the inner and larger of the two moons of Mars, was taken by the Mars Global Surveyor on August 19, 1998. The Thermal Emission Spectrometer (TES) measured the brightness of thermal radiation at the same time the camera acquired this image. By analyzing the brightness, TES scientists could deduce the various fractions of the surface exposed to the Sun and their temperatures. This preliminary analysis shows that the surface temperature, dependent on slope and particle size, varies from a high of +25o F (-4o C) on the most illuminated slopes to -170o F (-112o C) in shadows. This large difference, and the fact that such differences can be found in close proximity, adds support to the notion that the surface of Phobos is covered by very small particles.

Malin Space Science Systems, Inc. and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Thermal Emission Spectrometer is operated by Arizona State University and was built by Raytheon Santa Barbara Remote Sensing. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

Sinus Meridiani: uncontrolled Mars Global Surveyor (MGS) Mars Orbital Camera (MOC): digital context photomosaic (250 megapixel resolution)

USGS Publications Warehouse

Noreen, Eric

2000-01-01

These images were processed from a raw format using Integrated Software for Images and Spectrometers (ISIS) to perform radiometric corrections and projection. All the images were projected in sinusoidal using a center longitude of 0 degrees. There are two versions of the mosaic, one unfiltered (sinusmos.tif), and one produced with all images processed through a box filter with an averaged pixel tone of 7.5 (sinusmosflt.tif). Both mosaics are ArcView-ArcInfo(2) ready in TIF format with associated world files (*.tfw).

Central Valles Marineris: uncontrolled Mars Global Surveyor (MGS) Mars Orbital Camera (MOC) digital context photomosaic (250 megapixel resolution)

USGS Publications Warehouse

Noreen, Eric

2000-01-01

These images were processed from a raw format using Integrated Software for Images and Spectrometers (ISIS) to perform radiometric corrections and projection. All the images were projected in sinusoidal using a center longitude of 70 degrees. There are two versions of the mosaic, one unfiltered (vallesmos.tif), and one produced with all images processed through a box filter with an averaged pixel tone of 7.699 (vallesmosflt.tif). Both mosaics are ArcView-ArcInfo ready in TIF format with associated world files (*.tfw).

Mars at Ls 288°: Syrtis Major

NASA Image and Video Library

2005-09-21

This picture, released 21 September 2005, is a composite of Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) daily global images acquired at Ls 288° during a previous Mars year. This month, Mars looks similar, as Ls 288° occurred in mid-September 2005. The picture shows the Syrtis Major face of Mars. Over the course of the month, additional faces of Mars as it appears at this time of year are being posted for MOC Picture of the Day. Ls, solar longitude, are a measure of the time of year on Mars. Mars travels 360° around the Sun in 1 Mars year. The year begins at Ls 0°, the start of northern spring and southern autumn.

Breaking Trail

NASA Technical Reports Server (NTRS)

2006-01-01

25 May 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows gullies in the north wall of a crater south of Proctor Crater in Noachis Terra. To form, the gullies might have required liquid water. Dark streaks cutting across the scene were formed by passing dust devils.

Location near: 51.4oS, 331.4oW Image width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Summer

Polygons in Utopia

NASA Technical Reports Server (NTRS)

2005-01-01

14 April 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a typical view of polygon-cracked and pitted surfaces unique to western Utopia Planitia. No other place on Mars has this appearance. Some Mars scientists have speculated that ground ice may be responsible for these landforms.

Location near: 42.3oN, 275.6oW Image width: 3 km (1.9 mi) Illumination from: lower left Season: Northern Summer

Incomplete Puzzle

NASA Technical Reports Server (NTRS)

2006-01-01

15 April 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a mid-summer view of a portion of the south polar residual cap of Mars. The large, relatively flat-lying, puzzle-like pieces in this scene are mesas composed largely of solid carbon dioxide.

Location near: 85.5oS, 76.8oW Image width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Summer

Plains Traveler

NASA Technical Reports Server (NTRS)

2006-01-01

10 April 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a dust devil traveling across a plain west-southwest of Schiaparelli Crater, in far eastern Sinus Meridiani. The dust devil is casting a shadow toward the northeast, just south (below) of an egg-shaped crater.

Location near: 6.4oS, 349.3oW Image width: 3 km (1.9 mi) Illumination from: lower left Season: Southern Summer

Landslide in Mutch

NASA Technical Reports Server (NTRS)

2005-01-01

18 November 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows the east margin of a landslide off the southern rim of Mutch Crater in the Xanthe Terra region of Mars. This particular landslide was likely triggered by a meteor impact that occurred nearby.

Location near: 0.7oS, 55.9oW Image width: width: 3 km (1.9 mi) Illumination from: lower left Season: Southern Spring

Martian Fingerprints

NASA Technical Reports Server (NTRS)

2005-01-01

9 April 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows patterned ground on the martian northern plains. The circular features are buried meteor impact craters; the small dark dots associated with them are boulders. The dark feature at left center is a wind streak.

Location near: 75.1oN, 303.0oW Image width: 3 km (1.9 mi) Illumination from: lower left Season: Northern Summer

More South Polar 'Swiss Cheese'

NASA Technical Reports Server (NTRS)

2000-01-01

This image is illuminated by sunlight from the upper left.

Some of the surface of the residual south polar cap has a pattern that resembles that of sliced, swiss cheese. Shown here at the very start of southern spring is a frost-covered surface in which there are two layers evident--a brighter upper layer into which are set swiss cheese-like holes, and a darker, lower layer that lies beneath the 'swiss cheese' pattern. Nothing like this exists anywhere on Mars except within the south polar cap.

This is a Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image acquired on August 2,1999. It is located near 84.8oS, 71.8oW, and covers an area 3 km across and about 6.1 km long (1.9 by 3.8 miles).

Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

Schiaparelli Crater Rim and Interior Deposits - High Resolution Image

NASA Technical Reports Server (NTRS)

1998-01-01

A portion of the rim and interior of the large impact crater Schiaparelli is seen at high resolution in this image acquired October 18, 1997 by the Mars Global Surveyor Orbiter Camera (MOC). The area covered is very small--3.9 X 10.2 km (2.4 X 6.33 mi)--but is seen at 63 times higher resolution than the Viking image. The subdued relief and bright surface are attributed to blanketing by dust; many small craters have been completely filled in, and only the most recent (and very small) craters appear sharp and bowl-shaped. Some of the small craters are only 10-12 m (30-35 feet) across. Occasional dark streaks on steeper slopes are small debris slides that have probably occurred in the past few decades. The two prominent, narrow ridges in the center of the image may be related to the adjustment of the crater floor to age or the weight of the material filling the basin.

Malin Space Science Systems (MSSS) and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

Evidence for Recent Liquid Water on Mars: Channels and Aprons in East Gorgonum Crater

NASA Technical Reports Server (NTRS)

2000-01-01

[figure removed for brevity, see original site] Warning!This link leads to a very large image that may be too long for some web browsers (in these cases, you must save the link to your desktop and view with other software) [figure removed for brevity, see original site]

This suite of Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) pictures provides a vista of martian gullies on the northern wall of a 12 kilometer-(7.4 mile)-wide meteor impact crater east of the Gorgonum Chaos region on the red planet.

The first picture (above left) is a composite of three different high resolution MOC views obtained in 1999 and 2000. The second picture (above right)shows the location of the high resolution views relative to the whole crater as it appeared in the highest resolution image previously acquired of the area, taken by the Viking 1 orbiter in 1978. The release image (top) shows a close-up of one of the channels and debris aprons found in the northwestern quarter of the impact crater.

Some of the channels in this crater are deeply-entrenched and cut into lighter-toned deposits. The numerous channels and apron deposits indicate that many tens to hundreds of individual events involving the flow of water and debris have occurred here. The channels and aprons have very crisp, sharp relief and there are no small meteor impact craters on them, suggesting that these features are extremely young relative to the 4.5 billion year history of Mars. It is possible that these landforms are still being created by water seeping from the layered rock in the crater wall today.

The crater has no name and it is located near 37.4oS, 168.0oW. The composite view in (above left) includes a picture taken by MOC on September 10, 1999, a picture obtained April 26, 2000, and another on May 22, 2000. The scene from left to right (including the dark gap between photos) covers an area approximately 7.6 kilometers (4.7 miles) wide by 18 km (11.1 mi) long. Sunlight illuminates the scene from the upper left. MOC high resolution images are taken black-and-white (grayscale); the color seen here has been synthesized from the colors of Mars observed by the MOC wide angle cameras and by the Viking Orbiters in the late 1970s.

A Dust Devil Making a Streak and Climbing a Crater Wall

NASA Technical Reports Server (NTRS)

2002-01-01

MGS MOC Release No. MOC2-318, 8 August 2002 [figure removed for brevity, see original site] One of the key elements of the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) Extended Mission is to look for and monitor changes taking place on the planet over the course of a second--and, eventually, a third--martian year. MGS is now well into its second Mars year, which will draw to a close in December 2002. Among the changes the MOC has observed are streaks believed to be caused by the passage of dust devils. Thousands of MOC images show these streaks, dozens show that they change over time, but far fewer images have actually captured a dust devil in the act of creating a streak. At the center right of this image (above left) is a dust devil that, on May 21, 2002, was seen climbing the wall of a crater at 4.1oS, 9.5oW. This crater (above right) is in western Terra Meridiani. The dust devil was moving toward the northeast (upper right), leaving behind a dark trail where a thin coating of surficial dust was removed or disrupted as the dust devil advanced. Dust devils most commonly form after noon on days when the martian air is still (that is, when there isn't even a faint breeze). On such days, the ground is better able to heat up the air immediately above the surface. As the warmed near-surface air begins to rise, it also begins to spin, creating a vortex. The spinning column then moves across the surface and picks up loose dust (if any is present). The dust makes the vortex visible and gives it a tornado-like appearance. The dust devil in this image has a very short, dark shadow cast to the right of the bright column; this shadow is short because the sun was nearly overhead.

100 New Impact Crater Sites Found on Mars

NASA Astrophysics Data System (ADS)

Kennedy, M. R.; Malin, M. C.

2009-12-01

Recent observations constrain the formation of 100 new impact sites on Mars over the past decade; 19 of these were found using the Mars Global Surveyor Mars Orbiter Camera (MOC), and the other 81 have been identified since 2006 using the Mars Reconnaissance Orbiter Context Camera (CTX). Every 6 meter/pixel CTX image is examined upon receipt and, where they overlap images of 0.3-240 m/pixel scale acquired by the same or other Mars-orbiting spacecraft, we look for features that may have changed. New impact sites are initially identified by the presence of a new dark spot or cluster of dark spots in a CTX image. Such spots may be new impact craters, or result from the effect of impact blasts on the dusty surface. In some (generally rare) cases, the crater is sufficiently large to be resolved in the CTX image. In most cases, however, the crater(s) cannot be seen. These are tentatively designated as “candidate” new impact sites, and the CTX team then creates an opportunity for the MRO spacecraft to point its cameras off-nadir and requests that the High Resolution Imaging Science Experiment (HiRISE) team obtain an image of ~0.3 m/pixel to confirm whether a crater or crater cluster is present. It is clear even from cursory examination that the CTX observations are areographically biased to dusty, higher albedo areas on Mars. All but 3 of the 100 new impact sites occur on surfaces with Lambert albedo values in excess of 23.5%. Our initial study of MOC images greatly benefited from the initial global observations made in one month in 1999, creating a baseline date from which we could start counting new craters. The global coverage by MRO Mars Color Imager is more than a factor of 4 poorer in resolution than the MOC Wide Angle camera and does not offer the opportunity for global analysis. Instead, we must rely on partial global coverage and global coverage that has taken years to accumulate; thus we can only treat impact rates statistically. We subdivide the total data set of 100 sites into 3 sets of observations: the original 19 MOC observations found in a survey of 15% of the planet, craters found only in CTX repeat coverage of 7% of Mars, and the remaining 69 craters found in a data set covering 40% of the planet. Using the mean interval between the latest observation preceding the impact and the first observation showing the impact for these groups of craters, we determine that the cratering rate is roughly 8 ± 6 x 10-7 craters/km2/yr for craters greater than ~1 m diameter. The cratering rate on Mars is sufficiently high to warrant consideration both for scientific studies and as a hazard to future exploration. Impacts are sufficiently frequent to act as seismic sources for studies of shallow crustal structure, if a seismic network is sufficiently dispersed and long-lived. Impacts large enough to provide information about deep interior structure are rare but probably occur on a decadal timescale. As recently noted in Science, new craters can be used to probe the distribution of subsurface ice and to provide samples from shallow depths that otherwise require meter-scale drilling systems. There is a finite probability that visitors to Mars for more than a month or two will hear or feel the effects of a nearby impact.

KENNEDY SPACE CENTER, FLA. - In the Payload Hazardous Servicing Facility at KSC, installation is under way of the Mars Orbiter Camera (MOC) on the Mars Global Surveyor spacecraft. The MOC is one of a suite of six scientific instruments that will gather data about Martian topography, mineral distribution and weather during a two-year period. The Mars Global Surveyor is slated for launch aboard a Delta II expendable launch vehicle on Nov. 6, the beginning of a 20-day launch period.

NASA Image and Video Library

1996-08-19

KENNEDY SPACE CENTER, FLA. - In the Payload Hazardous Servicing Facility at KSC, installation is under way of the Mars Orbiter Camera (MOC) on the Mars Global Surveyor spacecraft. The MOC is one of a suite of six scientific instruments that will gather data about Martian topography, mineral distribution and weather during a two-year period. The Mars Global Surveyor is slated for launch aboard a Delta II expendable launch vehicle on Nov. 6, the beginning of a 20-day launch period.

Multitemporal observations of identical active dust devils on Mars with the High Resolution Stereo Camera (HRSC) and Mars Orbiter Camera (MOC)

NASA Astrophysics Data System (ADS)

Reiss, D.; Zanetti, M.; Neukum, G.

2011-09-01

Active dust devils were observed in Syria Planum in Mars Observer Camera - Wide Angle (MOC-WA) and High Resolution Stereo Camera (HRSC) imagery acquired on the same day with a time delay of ˜26 min. The unique operating technique of the HRSC allowed the measurement of the traverse velocities and directions of motion. Large dust devils observed in the HRSC image could be retraced to their counterparts in the earlier acquired MOC-WA image. Minimum lifetimes of three large (avg. ˜700 m in diameter) dust devils are ˜26 min, as inferred from retracing. For one of these large dust devil (˜820 m in diameter) it was possible to calculate a minimum lifetime of ˜74 min based on the measured horizontal speed and the length of its associated dust devil track. The comparison of our minimum lifetimes with previous published results of minimum and average lifetimes of small (˜19 m in diameter, avg. min. lifetime of ˜2.83 min) and medium (˜185 m in diameter, avg. min. lifetime of ˜13 min) dust devils imply that larger dust devils on Mars are active for much longer periods of time than smaller ones, as it is the case for terrestrial dust devils. Knowledge of martian dust devil lifetimes is an important parameter for the calculation of dust lifting rates. Estimates of the contribution of large dust devils (>300-1000 m in diameter) indicate that they may contribute, at least regionally, to ˜50% of dust entrainment by dust devils into the atmosphere compared to the dust devils <300 m in diameter given that the size-frequency distribution follows a power-law. Although large dust devils occur relatively rarely and the sediment fluxes are probably lower compared to smaller dust devils, their contribution to the background dust opacity by dust devils on Mars could be at least regionally large due to their longer lifetimes and ability of dust lifting into high atmospheric layers.

Mars on 25 December 2003

NASA Technical Reports Server (NTRS)

2004-01-01

8 January 2004 This is how Mars appeared to the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) wide angle system on 25 December 2003, the day that Beagle 2 and Mars Express reached the red planet. The large, dark region just left of center is Syrtis Major, a persistent low albedo terrain known to astronomers for nearly four centuries before the first spacecraft went to Mars. Immediately to the right (east) of Syrtis Major is the somewhat circular plain, Isidis Planitia. Beagle 2 arrived in Isidis Planitia only about 18 minutes before Mars Global Surveyor flew over the region and acquired a portion of this global view. Relative to other global images of Mars acquired by MGS over the past several martian years, the surface features were not as sharp and distinct on 25 December 2003 because of considerable haze kicked up by large dust storms in the western and southern hemispheres during th previous two weeks. The picture is a composite of several MGS MOC red and blue daily global images that have been map-projected and digitally wrapped to a sphere. Although the effect here is minor, inspection of this mosaic shows zones that appear smudged or blurry. The high dust opacity on 25 December impacted MOC's oblique viewing geometry toward the edges of each orbit's daily global mapping image, thus emphasizing the 'blurry' zones between images acquired on successive orbits.

Devilish Details

NASA Technical Reports Server (NTRS)

2005-01-01

23 September 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a small, springtime dust devil creating a dark streak on the plains of Argyre. The small, bright dot is the dust devil. Many other dark streaks on the plains indicate the areas where other dust devils had passed within the past several weeks before this July 2005 image was acquired.

Location near: 44.6oS, 40.3oW Image width: width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Spring

Mars at Ls 193°: Acidalia/Mare Erythraeum

NASA Image and Video Library

2005-04-12

This picture is a composite of Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) daily global images acquired at Ls 193° during a previous Mars year. This month, Mars looks similar, as Ls 193° occurs in mid-April 2005. The picture shows the Acidalia/Mare Erythraeum face of Mars. Over the course of the month, additional faces of Mars as it appears at this time of year are being posted for MOC Picture of the Day. Ls, solar longitude, is a measure of the time of year on Mars. Mars travels 360° around the Sun in 1 Mars year. The year begins at Ls 0°, the start of northern spring and southern autumn. Location near: 47.3°N, 294.0°W Image width: ~3 km (~1.9 mi) Illumination from: lower left Season: Northern Summer. http://photojournal.jpl.nasa.gov/catalog/PIA07837

Mars at Ls 93o: Elysium/Mare Cimmerium

NASA Technical Reports Server (NTRS)

2006-01-01

22 August 2006 This picture is a composite of Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) daily global images acquired at Ls 93o during a previous Mars year. This month, Mars looks similar, as Ls 93o occurred in mid-August 2006. The picture shows the Elysium/Mare Cimmerium face of Mars. Over the course of the month, additional faces of Mars as it appears at this time of year are being posted for MOC Picture of the Day. Ls, solar longitude, is a measure of the time of year on Mars. Mars travels 360o around the Sun in 1 Mars year. The year begins at Ls 0o, the start of northern spring and southern autumn.

Location near: 86.1oN, 208.5oW Image width: 3 km (1.9 mi) Illumination from: lower left Season: Northern Summer/Southern Winter

Mars at Ls 176o: Elysium/Mare Cimmerium

NASA Technical Reports Server (NTRS)

2005-01-01

22 March 2005 This picture is a composite of Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) daily global images acquired at Ls 176o during a previous Mars year. This month, Mars looks similar, as Ls 176o occurred in mid-March 2005. The picture shows the Elysium/Mare Cimmerium face of Mars. Over the course of the month, additional faces of Mars as it appears at this time of year are being posted for MOC Picture of the Day. Ls, solar longitude, is a measure of the time of year on Mars. Mars travels 360o around the Sun in 1 Mars year. The year begins at Ls 0o, the start of northern spring and southern autumn.

Location near: 79.1oN, 228.8oW Image width: 3 km (1.9 mi) Illumination from: lower left Season: Northern Summer/Southern Winter

Mars at Ls 193o: Acidalia/Mare Erythraeum

NASA Technical Reports Server (NTRS)

2005-01-01

12 April 2005 This picture is a composite of Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) daily global images acquired at Ls 193o during a previous Mars year. This month, Mars looks similar, as Ls 193o occurs in mid-April 2005. The picture shows the Acidalia/Mare Erythraeum face of Mars. Over the course of the month, additional faces of Mars as it appears at this time of year are being posted for MOC Picture of the Day. Ls, solar longitude, is a measure of the time of year on Mars. Mars travels 360o around the Sun in 1 Mars year. The year begins at Ls 0o, the start of northern spring and southern autumn.

Location near: 47.3oN, 294.0oW Image width: 3 km (1.9 mi) Illumination from: lower left Season: Northern Summer

Polar Polygons

NASA Technical Reports Server (NTRS)

2005-01-01

18 August 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows dark-outlined polygons on a frost-covered surface in the south polar region of Mars. In summer, this surface would not be bright and the polygons would not have dark outlines--these are a product of the presence of seasonal frost.

Location near: 77.2oS, 204.8oW Image width: width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Spring

Broken Plain

NASA Technical Reports Server (NTRS)

2006-01-01

2 February 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows polygonally patterned ground on the floor of a trough in the southern hemisphere of Mars. The polygons could be an indicator that ground ice is or was present at this location. The dark streaks were formed by passing dust devils.

Location near: 67.4oS, 240.3oW Image width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Summer

Features in Aureum Chaos

NASA Technical Reports Server (NTRS)

2004-01-01

12 November 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows light-toned, sedimentary rock outcrops in the Aureum Chaos region of Mars. On the brightest and steepest slope in this scene, dry talus shed from the outcrop has formed a series of dark fans along its base. These outcrops are located near 3.4oS, 27.5oW. The image covers an area approximately 3 km (1.9 mi) across and sunlight illuminates the scene from the upper left.

Dark Mesas of Aram Chaos

NASA Technical Reports Server (NTRS)

2004-01-01

6 July 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows several dark-toned mesas surrounded by light-toned sedimentary rock outcrops in Aram Chaos, a large impact basin -- over 200 km (more than 125 mi) across. These mesas are remnants of a once more extensive rock unit. The image is located near 2.0oN, 20.2oW, and covers an area about 3 km (1.9 mi) wide. Sunlight illuminates the scene from the left.

Tharsis Flood Features

NASA Technical Reports Server (NTRS)

2005-01-01

17 July 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows channels carved by catastrophic floods in the Tharsis region of Mars. This area is located northwest of the volcano, Jovis Tholus, and east of the large martian volcano, Olympus Mons. The terrain is presently mantled with fine dust.

Location near: 20.8oN, 118.8oW Image width: width: 3 km (1.9 mi) Illumination from: lower left Season: Northern Autumn

Waning Cap

NASA Technical Reports Server (NTRS)

2006-01-01

14 June 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows the outer edge of the south polar residual cap of Mars. During summer, the scarps that delineate the sides of the mesas, retreat (on average) by about 3 meters (10 feet) owing to the sublimation of solid carbon dioxide.

Location near: 85.6oS, 349.8oW Image width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Summer

Polar Landforms

NASA Technical Reports Server (NTRS)

2005-01-01

10 August 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows eroded remnants of carbon dioxide ice in the south polar residual cap of Mars. The scarps that outline each small mesa have retreated about 3 meters (10 feet) per Mars year since MGS began orbiting the red planet in 1997.

Location near: 87.0oS, 31.9oW Image width: width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Spring

Gullies Galore

NASA Technical Reports Server (NTRS)

2006-01-01

27 April 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows an array of gullies in the north-northwest wall of a crater in Terra Cimmeria. These features may have been formed through the interaction of several processes including, but not limited to, mass wasting and/or seepage and runoff of groundwater.

Location near: 33.5oS, 207.2oW Image width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Summer

Cross-Cutting Faults

NASA Technical Reports Server (NTRS)

2005-01-01

16 May 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows cross-cutting fault scarps among graben features in northern Tempe Terra. Graben form in regions where the crust of the planet has been extended; such features are common in the regions surrounding the vast 'Tharsis Bulge' on Mars.

Location near: 43.7oN, 90.2oW Image width: 3 km (1.9 mi) Illumination from: lower left Season: Northern Summer

Security Blanket

NASA Technical Reports Server (NTRS)

2006-01-01

2 June 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows material on the floor of a crater in Noachis Terra, west of Hellas Planitia. Windblown features, both the large, dark-toned sand dunes and smaller, light-toned ripples, obscure and perhaps, protect portions of the crater floor from further modification by erosional processes.

Location near: 45.4oS, 331.2oW Image width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Summer

Ascraeus Depression

NASA Technical Reports Server (NTRS)

2005-01-01

29 December 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows house-sized boulders and layered volcanic rock exposed in a pit on the north flank of the giant Tharsis volcano, Ascraeus Mons. The pit most likely formed by collapse. Dust mantles much of the surrounding terrain and the pit floor.

Location near: 12.9oN, 101.6oW Image width: 3 km (1.9 mi) Illumination from: lower left Season: Southern Winter

Ripples in Tempe Mensa Region

NASA Technical Reports Server (NTRS)

2004-01-01

1 February 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows large windblown ripples (or, some might say, small dunes) in troughs between mesas of the Tempe Mensa region. The ripples are generally perpendicular to the trough walls, indicating that [missing text] the features blew through these canyons. The image is located near 33.5oN, 69.2oW. The picture covers an area 3 km (1.9 mi) wide; sunlight illuminates the scene from the lower left.

Processing of A New Digital Orthoimage Map of The Martian Western Hemisphere Using Data Obtained From The Mars Orbiter Camera At A Resolution of 256 Pixel/deg

NASA Astrophysics Data System (ADS)

Wählisch, M.; Niedermaier, G.; van Gasselt, S.; Scholten, F.; Wewel, F.; Roatsch, T.; Matz, K.-D.; Jaumann, R.

We present a new digital orthoimage map of Mars using data obtained from the CCD line scanner Mars Orbiter Camera (MOC) of the Mars Global Surveyor Mis- sion (MGS) [1,2]. The map covers the Mars surface from 0 to 180 West and from 60 South to 60 North with the MDIM2 resolution of 256 pixel/degree and size. Image data processing has been performed using multiple programs, developed by DLR, Technical University of Berlin [3], JPL, and the USGS. 4,339 Context and 183 Geodesy images [2] were included. After radiometric corrections, the images were Mars referenced [4], geometrically corrected [5] and orthoprojected using a global Martian Digital Terrain Model (DTM) with a resolution of 64 pixel/degree, developed at DLR and based on MGS Mars Orbiter Laser Altimeter (MOLA) data [6]. To elim- inate major differences in brightness between the individual images of the mosaics, high- and low-pass filter processing techniques were applied for each image. After filtering, the images were mosaicked without registering or using block adjustment techniques in order to improve the geometric quality. It turns out that the accuracy of the navigation data has such a good quality that the orthoimages fit very well to each other. When merging the MOC mosaic with the MOLA data using IHS- trans- formation, we recognized very good correspondence between these two datasets. We create a topographic image map of the Coprates region (MC­18) adding contour lines derived from the global DTM to the mosaic. These maps are used for geological and morphological interpretations in order to review and improve our current Viking-based knowledge about the Martian surface. References: [1] www.mssss.com, [2] Caplinger, M. and M. Malin, "The Mars Or- biter Camera Geodesy Campaign, JGR, in press, [3] Scholten, F., Vol XXXI, Part B2, Wien 1996, p.351-356, [4] naïf.jpl.nasa.gov, [5] R.L.Kirk. et al. (2001), "Geometric Calibration of the Mars Orbiter Cameras and Coalignment with Mars Orbiter Laser Altimeter", LPSC XXXII, [6] wufs.wustl.edu

Beagle-2 landing site atlas

NASA Astrophysics Data System (ADS)

Michael, G.; Chicarro, A.; Rodionova, J.; Shevchenko, V.; Ilukhina, J.; Kozlova, K.

2003-04-01

The Beagle-2 lander of the Mars Express mission will come to rest on the surface of Isidis Planitia in late December 2003 to carry out a range of geochemistry and exobiology experi-ments. We are compiling an atlas of the presently available data products pertinent to the landing site at 11.6N 90.75E, which is intended for distribution both as a printed and an electronic resource. The atlas will include Viking and MOC-WA image mosaics, and a catalogue of high-resolution im-ages from MOC and THEMIS with location maps. There will be various MOLA topography-based products: colour-scaled, contoured, and shaded maps, slope, and detrended relief. Simulated camera panoramas from various potential landing locations may assist in determining the spacecraft’s position. Other maps, both raw, and in composites with image mosa-ics, will cover TES thermal inertia and spectroscopy, and Odyssey gamma and neutron spectroscopy. Maps at the scale of the Isidis context will additionally cover geology, tem-perature cycles, and atmospheric circulation. Sample are shown below.

10 Weeks of Change

NASA Technical Reports Server (NTRS)

2004-01-01

11 June 2004 These four Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) images show north polar sand dunes as they appeared on four different days over the past ten weeks. In summer, the dunes would be darker than the substrate on which they occur. However, it is currently spring in the northern hemisphere, and the dunes are still covered with frost from the previous winter. The MGS MOC has been busy over the past several months, documenting the changes in frost patterns that occur on dunes and interdune substrates all over the north polar region. The site shown here was imaged on 30 March, 23 April, 16 May, and 9 June 2004. The bright frost that covers the dunes progressively changes from one image to the next, as dark spots develop and frost sublimes away. This defrosting dune monitor site is located near 80.0oN, 237.5oW. Each strip is about 1.1 km (0.7 mi) wide and illuminated by sunlight from the lower left.

Sedimentary Rocks of Aram Chaos

NASA Technical Reports Server (NTRS)

2004-01-01

10 May 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows outcroppings of light-toned, layered, sedimentary rock within Aram Chaos, an ancient, partly-filled impact crater located near 3.2oN, 19.9oW. This 1.5 meters (5 feet) per pixel picture is illuminated by sunlight from the left and covers an area about 3 km (1.9 mi) across.

Landslide in Sirenum

NASA Technical Reports Server (NTRS)

2004-01-01

27 August 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a landslide deposit in a deep trough in Terra Sirenum near 26.1oS, 140.0oW. After the landslide occurred, subsequent erosion of the slope produced talus that covers part of the landslide deposit. This area is about 3 km (1.9 mi) across; sunlight illuminates the scene from the lower left.

Mars at Ls 211°: Elysium/Mare Cimmerium

NASA Image and Video Library

2005-05-24

This picture is a composite of Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) daily global images acquired at Ls 211° during a previous Mars year. This month, Mars looks similar, as Ls 211° occurred in mid-May 2005. The picture shows the Elysium/Mare Cimmerium face of Mars. Over the course of the month, additional faces of Mars as it appears at this time of year are being posted for MOC Picture of the Day. Ls, solar longitude, is a measure of the time of year on Mars. Mars travels 360° around the Sun in 1 Mars year. The year begins at Ls 0°, the start of northern spring and southern autumn. http://photojournal.jpl.nasa.gov/catalog/PIA07988

Mars at Ls 160o: Elysium/Mare Cimmerium

NASA Technical Reports Server (NTRS)

2005-01-01

This picture is a composite of Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) daily global images acquired at Ls 160o during a previous Mars year. This month, Mars looks similar, as Ls 160o occurred in mid-February 2005. The picture shows the Elysium/Mare Cimmerium face of Mars. Over the course of the month, additional faces of Mars as it appears at this time of year are being posted for MOC Picture of the Day. Ls, solar longitude, is a measure of the time of year on Mars. Mars travels 360o around the Sun in 1 Mars year. The year begins at Ls 0o--the start of northern spring and southern summer.

Season: Northern Summer/Southern Winter

Mars at Ls 66o: Elysium/Mare Cimmerium

NASA Technical Reports Server (NTRS)

2006-01-01

27 June 2006 This picture is a composite of Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) daily global images acquired at Ls 66o during a previous Mars year. This month, Mars looks similar, as Ls 66o occurred in mid-June 2006. The picture shows the Elysium/Mare Cimmerium face of Mars. Over the course of the month, additional faces of Mars as it appears at this time of year are being posted for MOC Picture of the Day. Ls, solar longitude, is a measure of the time of year on Mars. Mars travels 360o around the Sun in 1 Mars year. The year begins at Ls 0o, the start of northern spring and southern autumn.

Northern Spring/Southern Autumn

Pedestal Crater and Yardangs

NASA Technical Reports Server (NTRS)

2003-01-01

MGS MOC Release No. MOC2-444, 6 August 2003

This April 2003 Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a small meteor impact crater that has been modified by wind erosion. Two things happened after the crater formed. First, the upper few meters of surface material into which the meteor impacted was later eroded away by wind. The crater ejecta formed a protective armor that kept the material under the ejecta from been blown away. This caused the crater and ejecta to appear as if standing upon a raised platform--a feature that Mars geologists call a pedestal crater. Next, the pedestal crater was buried beneath several meters of new sediment, and then this material was eroded away by wind to form the array of sharp ridges that run across the pedestal crater's surface. These small ridges are known as yardangs. This picture is illuminated by sunlight from the upper left; it is located in west Daedalia Planum near 14.6oS, 131.9oW.

Landslide in Coprates

NASA Technical Reports Server (NTRS)

2004-01-01

This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows part of a large landslide complex off the north wall of Coprates Chasma in the Valles Marineris trough complex. The wall of Coprates Chasma occupies much of the upper and middle portions of the image; the landslide lobes are on the trough floor in the bottom half of the image. Large boulders the size of houses can be seen on these landslide surfaces. This image is located near 13.9 S, 56.7 W. The picture covers an area about 3 km (1.9 mi) wide. Sunlight illuminates the scene from the upper left.

Sirenum Fossae Trough

NASA Technical Reports Server (NTRS)

2000-01-01

[figure removed for brevity, see original site]

The Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) orbits the red planet twelve times each day. The number of pictures that MOC can take varies from orbit to orbit, depending upon whether the data are being stored in MGS's onboard tape recorder for playback at a later time, or whether the data are being sent directly back to Earth via a real-time radio link. More data can be acquired during orbits with real-time downlink.

During real-time orbits, the MOC team often will take a few random or semi-random pictures in between the carefully-selected, hand-targeted images. On rare occasions, one of these random pictures will surprise the MOC team. The picture shown here is an excellent example, because the high resolution view (top) is centered so nicely on a trough and an adjacent, shallow crater that it is as if someone very carefully selected the target for MOC. The high-resolution view covers an area only 1.1 km (0.7 mi) wide by 2.3 km (1.4 mi) long. Hitting a target such as this with such a small image is very difficult to do, on purpose, because there are small uncertainties in the predicted orbit, the maps used to select targets, and the minor adjustments of spacecraft pointing at any given moment. Nevertheless, a very impressive image was received.

The high resolution view crosses one of the troughs of the Sirenum Fossae near 31.2oS, 152.3oW. The context image (above) was acquired at the same time as the high resolution view on July 23, 2000. The small white box shows the location of the high resolution picture. The lines running diagonally across the context image from upper right toward lower left are the Sirenum Fossae troughs, formed by faults that are radial to the volcanic region of Tharsis. Both pictures are illuminated from the upper left. The scene shows part of the martian southern hemisphere nearly autumn.

Mars Shoreline Tests: Contact between Lycus Sulci and Amazonis Planitia

NASA Technical Reports Server (NTRS)

1999-01-01

This picture is the first MOC high resolution image that showed the contact between the Lycus Sulci uplands and Amazonis Planitia lowlands. In this subframe of MOC image SPO 1-225/03, Amazonis and Lycus Sulci are separated by a subtle rise that runs diagonally across the scene from near the lower left toward the upper right. The Amazonis plains are toward the top of the picture, the Lycus Sulci uplands are toward the bottom. Both surfaces have been cratered by small meteoroid impacts. The Amazonis plains surface has many small, nearly parallel ridges that may have formed by wind erosion. These ridges are not found on the Lycus Sulci surface. None of the features seen in this image look like typical seashore landforms found on Earth--i.e., there are no beaches, windblown coastal dunes, or even the wave-cut cliff that was thought to exist on the basis of previous Viking images. The picture is illuminated from the lower right and was acquired in April 1998. [figure removed for brevity, see original site]

Lycus Sulci is the name of a region of hills and ridges located north and northwest of the famous giant volcano, Olympus Mons (see inset, above). Viking images of the area where the western margin of the Lycus Sulci meets the smooth Amazonis plains (upper left in the figure above) led some researchers to conclude that the two surfaces were in contact along a cliff. The proposed cliff faces toward the smooth plains, and thus it was suggested that this might be the kind of cliff that forms from erosion by waves in a body of water as they break against a coastline. During the first year that Mars Global Surveyor (MGS) was orbiting the red planet (1997-1998), the Mars Orbiter Camera (MOC) acquired three high-resolution images along the contact between the Lycus Sulci hills and the Amazonis plains. The location of the portion of each image that is illustrated below is shown in this figure by a small, white box identified by the archival image number (e.g., 'SPO2-428/03' refers to the 3rd image taken on the 428th orbit during the Science Phasing Orbits 2 phase of the MGS mission). The regional context view shown here is a portion of Viking orbiter image 851A29; its center is near 32oN, 114oW and it is illuminated from the right. [figure removed for brevity, see original site] MRPS 95319

Lycus Sulci and Amazonis Planitia are shown here separated by a rise that runs diagonally across the scene from near the lower left toward the upper right. This picture is a subframe of MOC image SPO2-428/03, taken in July 1998. The Lycus Sulci uplands here are more roughly-textured than in the previous image, and the flat Amazonis plains appear to be more smooth and lack the small parallel ridges seen in the earlier view. The lack of the small ridges might be real, or they might be present but cannot be seen because this picture has a lower resolution than the previous one. This image, too, shows that the contact between Amazonis and Lycus Sulci is not a cliff, and once again there are no features that can be unambiguously identified as coastal landforms. [figure removed for brevity, see original site] MRPS 95320

This is the third MOC image obtained during the first year of MGS operations that shows the contact between Lycus Sulci and Amazonis Planitia. This picture, a subframe of SPO2-483/08, was taken in August 1998. The Lycus Sulciup lands at this location dominate the lower half of the picture, while the Amazonis plains cover the upper half. The uplands here exhibit many small buttes (bumps or knobs in lower right of the scene), and the contact zone between the upland and lowland includes a triangular-shaped ridge (center/right). As with the earlier views of the contact between Lycus Sulci and Amazonis, no features of obvious origin by coastal processes (e.g., erosion by waves crashing against ashore) are seen. The scene is illuminated from the right. [figure removed for brevity, see original site] [figure removed for brevity, see original site]

The first picture above shows the regional context of a Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) high-resolution image that was targeted in August 1998 with the intent to test the hypothesis that the northern plains of Mars were once the site of a vast ocean of liquid water. The second picture shows the resulting MOC image, numbered SPO2-515/05 and located at 40.0oN, 6.0oW in the transition zone between the Cydonia region and Acidalia Planitia, Mars.

The context image (first picture) includes several dark lines, some of which are labeled I and some are labeled G. These dark lines were proposed in previous, peer-reviewed scientific papers to be possible ocean shorelines located along the margins of the martian northern plains. Line I was called the Interior Plains Boundary, and line G was called the Gradational Boundary. The MGS MOC high resolution image was targeted such that it would examine the nature of line I, the Interior Plains Boundary.

The second figure shows the MOC high resolution view. The picture on the left side of the figure (second image) is the full MOC image and the white box indicates the location of the expanded view to the right. In the expanded view (the center of the figure), the location of line I--the proposed shoreline--is shown by a dashed curve. The dashed curve follows a subtle, shallow trough. None of the types of coastal landforms common on Earth--such as a beach, wave-cut cliff or terrace, or coastal dune fields, are seen at this location. If an ocean had once been present, then the water would have covered the top 2/3 of the expanded view--i.e., water would have lapped up against the rounded mounds in the lower 1/3 of this picture. Instead of coastal landforms, the MOC image exhibits a dark surface in its upper 1/3. The dark surface covers older, rounded hills and has a low, lobate escarpment along its southern margin. This escarpment faces south--that is, it faces toward the once-proposed coastline. In other words, the escarpment faces in a direction opposite of what would be expected for a coastal environment.

The context picture uses Viking orbiter image 561a24 as a base. [figure removed for brevity, see original site] [figure removed for brevity, see original site] MRPS 50586

Mars Global Surveyor's (MGS) Mars Orbiter Camera (MOC) took the above picture (second of the two) of some massifs and mesas in the Cydonia region of Mars in early September 1998. The purpose of this image--number SPO2-532/04--was to test the hypothesis that the martian northern plains were once the site of an ocean or large sea. According to this hypothesis, and according to peer-reviewed and published maps, each one of the mesas and massifs in the two pictures above should have shorelines around their margins. The hypothesis holds that these were once islands and that waves would lap--and sometimes crash--against these landforms, rip off huge chunks of rock, and create steep cliffs and stair-stepped terraces in the rock.

The first picture above shows the regional context of the MOC high resolution view in Cydonia. The context picture, from Viking orbiter image 227S11, is illuminated from the right. The second picture above is a figure that shows the full SPO2-532/04 MOC image and two expanded views of portions of this image. Mesas are flat-topped uplands, and massifs are the more triangular, massive peaks. If an ocean had been present in this region, terraces that indicate erosion or bathtub rings of salt or carbonate deposits left by the retreat of this ocean as it dried up might be found around each mesa and massif. No such features are found, nor is it at all obvious why these mesas and massifs were portrayed in previously published figures as having shorelines around them. The MOC image is illuminated from the left. [figure removed for brevity, see original site] [figure removed for brevity, see original site]

If the northern plains of Mars had ever been the site of a vast ocean, then any highlands that protrude above these plains might be expected to exhibit shorelines. The somewhat curved, flat-topped mesa seen in Viking image 026A72 (first image)is bounded by a dark band. Prior to the Mars Global Surveyor (MGS) mission, this mesa was interpreted by some researchers as having been a possible island in an ancient, northern plains ocean. The dark band was interpreted to be a shoreline resulting from the action of waves lapping against the island's coast.

A high resolution image of the banded mesa--located on the Acidalia plains around 45oN, 7oW--was acquired by the MGS Mars Orbiter Camera (MOC) in August 1998, over twenty years after the Viking image was taken. A subframe of this image--SPO2-515/06--is shown in the second image. In the MOC image, the dark band resolves into a series of narrower bright and dark bands. Each band has a slightly different texture and brightness. Furthermore, what appeared to be a sunlit escarpment bounding the north side of the mesa in the Viking image appears in the MOC image to be only a shallow slope rather than a scarp or cliff. The origin of the different bands is not known, but the most likely explanation that would be consistent with other MOC observations of Mars is that the mesa consists of layered rock, and that each band is an outcropping of a different layer of this rock. The different textures would result from the differing resistance to erosion of each layer. Both images shown here are illuminated from the left.

THE MARS ORBITER CAMERA IS INSTALLED ON THE MARS GLOBAL SURVEYOR

NASA Technical Reports Server (NTRS)

1996-01-01

In the Payload Hazardous Servicing Facility at KSC, installation is under way of the Mars Orbiter Camera (MOC) on the Mars Global Surveyor spacecraft. The MOC is one of a suite of six scientific instruments that will gather data during a two-year period about Martian topography, mineral distribution and weather. The Mars Global Surveyor is slated for launch aboard a Delta II expendable launch vehicle on November 6, the beginning of a 20-day launch period.

Hellas as a Possible Site of Ancient Ice-Covered Lakes on Mars

NASA Technical Reports Server (NTRS)

Moore, Jeffrey M.; Wilhelms, Don E.; DeVincenzi, Donald (Technical Monitor)

2002-01-01

Based on topographic, morphologic, and stratigraphic evidence, we propose that ancient water-laid sediment is the dominant component of deposits within Hellas Planitia, Mars. Multiply layered sediment is manifested by alternating benches and scarps visible in Mars Orbiting Camera narrow-angle (MOC NA) images. Viking Orbiter camera and MOC NA images were used to map contacts and stratigraphically order the different materials units within Hellas. Mar's Orbiting Laser Altimeter (MOLA) data reveal that the contacts of these sedimentary units, as well as a number of scarps or other abrupt changes in landscape texture, trace contours of constant elevation for thousands of km, and in one case all around the basin. Channels, consensually interpreted to be cut by water, lead into the basin. MOLA results indicate that the area encompassed by greater Hellas' highest closed contour is nearly one-fifth that of the entire northern plains, making the Hellas 'drainage' area much larger than previously reported. If lakes formed under climatic conditions similar to the modern Martian climate, they would develop thick ice carapaces, then the lakes would eventually sublimate away. Two units within Hellas exhibit a reticulate or honeycomb pattern we speculate are impressions made by lake-lowered ice blocks grounding into initially soft mud.

Hellas as a possible site of ancient ice-covered lakes on Mars

USGS Publications Warehouse

Moore, Johnnie N.; Wilhelms, D.E.

2001-01-01

Based on topographic, morphologic, and stratigraphic evidence, we propose that ancient water-laid sediment is the dominant component of deposits within Hellas Planitia, Mars. Multiple-layered sediment is manifested by alternating benches and scarps visible in Mars orbiting camera narrow-angle (MOC NA) images. Viking Orbiter camera and MOC NA images were used to map contacts and stratigraphically order the different materials units within Hellas. Mars orbiting laser altimeter (MOLA) data reveal that the contacts of these sedimentary units, as well as a number of scarps or other abrupt changes in landscape texture, trace contours of constant elevation for thousands of km, and in one case all around the basin. Channels, consensually interpreted to be cut by water, lead into the basin. MOLA results indicate that the area encompassed by greater Hellas' highest closed contour is nearly one-fifth that of the entire northern plains, making the Hellas "drainage" area much larger than previously reported. If lakes formed under climatic conditions similar to the modern Martian climate, they would develop thick ice carapaces, then the lakes would eventually sublimate away. Two units within Hellas exhibit a reticulate or honeycomb pattern, which we speculate are impressions made by lake-lowered ice blocks grounding into initially soft mud.

Fretted Terrain Mass Movement

NASA Technical Reports Server (NTRS)

2005-01-01

18 April 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows the results of a small mass movement in a fretted terrain valley in the Coloe Fossae region of Mars (see upper right quarter of the image). The term, mass movement, is usually applied to landslides, although it is unclear in this case whether the landform resulted from a single, catastrophic landslide, or the slow creep of ice-rich debris.

Location near: 35.3oN, 303.1oW Image width: 3 km (1.9 mi) Illumination from: upper left Season: Northern Summer

Marte Vallis

NASA Technical Reports Server (NTRS)

2005-01-01

16 December 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows the results of catastrophic flooding in Marte Vallis, Mars. Marte is the Spanish word for Mars. Many of the major valleys on the red planet are named for the word for 'Mars' in the various languages of Earth. This image shows just a very small portion of the hundreds-of-kilometers-long Marte Vallis system.

Location near: 17.4oN, 174.7o Image width: width: 3 km (1.9 mi) Illumination from: lower left Season: Northern Winter

Ripples and Dunes

NASA Technical Reports Server (NTRS)

2006-01-01

21 July 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a small portion of the floor of Kaiser Crater in the Noachis Terra region, Mars. The terrain in the upper (northern) half of the image is covered by large windblown ripples and a few smoother-surfaced sand dunes. The dominant winds responsible for these features blew from the west/southwest (left/lower left).

Location near: 47.2oS, 341.3oW Image width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Winter

Mars at Ls 79o: Acidalia/Mare Erythraeum

NASA Technical Reports Server (NTRS)

2006-01-01

11 July 2006 This picture is a composite of Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) daily global images acquired at Ls 79o during a previous Mars year. This month, Mars looks similar, as Ls 79o occurs in mid-July 2006. The picture shows the Acidalia/Mare Erythraeum face of Mars. Over the course of the month, additional faces of Mars as it appears at this time of year are being posted for MOC Picture of the Day. Ls, solar longitude, is a measure of the time of year on Mars. Mars travels 360o around the Sun in 1 Mars year. The year begins at Ls 0o, the start of northern spring and southern autumn.

Season: Northern Spring/Southern Autumn

Mars at Ls 12o: Elysium/Mare Cimmerium

NASA Technical Reports Server (NTRS)

2006-01-01

28 February 2006 This picture is a composite of Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) daily global images acquired at Ls 12o during a previous Mars year. This month, Mars looks similar, as Ls 12o occurred in mid-February 2006. The picture shows the Elysium/Mare Cimmerium face of Mars. Over the course of the month, additional faces of Mars as it appears at this time of year are being posted for MOC Picture of the Day. Ls, solar longitude, is a measure of the time of year on Mars. Mars travels 360o around the Sun in 1 Mars year. The year begins at Ls 0o, the start of northern spring and southern autumn.

Season: Northern Spring/Southern Autumn

Mars at Ls 53o: Elysium/Mare Cimmerium

NASA Technical Reports Server (NTRS)

2006-01-01

23 May 2006 This picture is a composite of Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) daily global images acquired at Ls 53o during a previous Mars year. This month, Mars looks similar, as Ls 53o occurred in mid-May 2006. The picture shows the Elysium/Mare Cimmerium face of Mars. Over the course of the month, additional faces of Mars as it appears at this time of year are being posted for MOC Picture of the Day. Ls, solar longitude, is a measure of the time of year on Mars. Mars travels 360o around the Sun in 1 Mars year. The year begins at Ls 0o, the start of northern spring and southern autumn.

Season: Northern Spring/Southern Autumn

Mars at Ls 12o: Acidalia/Mare Erythraeum

NASA Technical Reports Server (NTRS)

2006-01-01

15 February 2006 This picture is a composite of Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) daily global images acquired at Ls 12o during a previous Mars year. This month, Mars looks similar, as Ls 12o occurs in mid-February 2006. The picture shows the Acidalia/Mare Erythraeum face of Mars. Over the course of the month, additional faces of Mars as it appears at this time of year are being posted for MOC Picture of the Day. Ls, solar longitude, is a measure of the time of year on Mars. Mars travels 360o around the Sun in 1 Mars year. The year begins at Ls 0o, the start of northern spring and southern autumn.

Season: Northern Winter/Southern Summer

Mars at Ls 25o: Elysium/Mare Cimmerium

NASA Technical Reports Server (NTRS)

2006-01-01

28 March 2006 This picture is a composite of Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) daily global images acquired at Ls 25o during a previous Mars year. This month, Mars looks similar, as Ls 25o occurred in mid-March 2006. The picture shows the Elysium/Mare Cimmerium face of Mars. Over the course of the month, additional faces of Mars as it appears at this time of year are being posted for MOC Picture of the Day. Ls, solar longitude, is a measure of the time of year on Mars. Mars travels 360o around the Sun in 1 Mars year. The year begins at Ls 0o, the start of northern spring and southern autumn.

Season: Northern Spring/Southern Autumn

Mars at Ls 53o: Acidalia/Mare Erythraeum

NASA Technical Reports Server (NTRS)

2006-01-01

9 May 2006 This picture is a composite of Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) daily global images acquired at Ls 53o during a previous Mars year. This month, Mars looks similar, as Ls 53o occurs in mid-May 2006. The picture shows the Acidalia/Mare Erythraeum face of Mars. Over the course of the month, additional faces of Mars as it appears at this time of year are being posted for MOC Picture of the Day. Ls, solar longitude, is a measure of the time of year on Mars. Mars travels 360o around the Sun in 1 Mars year. The year begins at Ls 0o, the start of northern spring and southern autumn.

Season: Northern Spring/Southern Autumn

Mars at Ls 230o: Elysium/Mare Cimmerium

NASA Technical Reports Server (NTRS)

2005-01-01

28 June 2005 This picture is a composite of Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) daily global images acquired at Ls 230o during a previous Mars year. This month, Mars looks similar, as Ls 230o occurred in mid-June 2005. The picture shows the Elysium/Mare Cimmerium face of Mars. Over the course of the month, additional faces of Mars as it appears at this time of year are being posted for MOC Picture of the Day. Ls, solar longitude, is a measure of the time of year on Mars. Mars travels 360o around the Sun in 1 Mars year. The year begins at Ls 0o, the start of northern spring and southern autumn.

Season Northern Autumn/Southern Spring

Mars at Ls 249o: Elysium/Mare Cimmerium

NASA Technical Reports Server (NTRS)

2005-01-01

26 July 2005 This picture is a composite of Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) daily global images acquired at Ls 249o during a previous Mars year. This month, Mars looks similar, as Ls 249o occurred in mid-July 2005. The picture shows the Elysium/Mare Cimmerium face of Mars. Over the course of the month, additional faces of Mars as it appears at this time of year are being posted for MOC Picture of the Day. Ls, solar longitude, is a measure of the time of year on Mars. Mars travels 360o around the Sun in 1 Mars year. The year begins at Ls 0o, the start of northern spring and southern autumn.

Season: Northern Autumn/Southern Spring

Mars at Ls 66o: Acidalia/Mare Erythraeum

NASA Technical Reports Server (NTRS)

2006-01-01

13 June 2006 This picture is a composite of Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) daily global images acquired at Ls 66o during a previous Mars year. This month, Mars looks similar, as Ls 66o occurs in mid-June 2006. The picture shows the Acidalia/Mare Erythraeum face of Mars. Over the course of the month, additional faces of Mars as it appears at this time of year are being posted for MOC Picture of the Day. Ls, solar longitude, is a measure of the time of year on Mars. Mars travels 360o around the Sun in 1 Mars year. The year begins at Ls 0o, the start of northern spring and southern autumn.

Season: Northern Spring/Southern Autumn

Mars at Ls 176°: Acidalia/Mare Erythraeum

NASA Image and Video Library

2005-03-08

This picture is a composite of Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) daily global images acquired at Ls 176° during a previous Mars year. This month, Mars looks similar, as Ls 176° occurs in mid-March 2005. The picture shows the Acidalia/Mare Erythraeum face of Mars. Over the course of the month, additional faces of Mars as it appears at this time of year are being posted for MOC Picture of the Day. Ls, solar longitude, is a measure of the time of year on Mars. Mars travels 360° around the Sun in 1 Mars year. The year begins at Ls 0°, the start of northern spring and southern autumn. Season: Northern Summer/Southern Winter. http://photojournal.jpl.nasa.gov/catalog/PIA07443

Mars at Ls 288o: Acidalia/Mare Erythraeum

NASA Technical Reports Server (NTRS)

2005-01-01

13 September 2005 This picture is a composite of Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) daily global images acquired at Ls 288o during a previous Mars year. This month, Mars looks similar, as Ls 288o occurs in mid-September 2005. The picture shows the Acidalia/Mare Erythraeum face of Mars. Over the course of the month, additional faces of Mars as it appears at this time of year are being posted for MOC Picture of the Day. Ls, solar longitude, is a measure of the time of year on Mars. Mars travels 360o around the Sun in 1 Mars year. The year begins at Ls 0o, the start of northern spring and southern autumn.

Season: Northern Winter/Southern Summer

Mars at Ls 324o: Elysium/Mare Cimmerium

NASA Technical Reports Server (NTRS)

2005-01-01

22 November 2005 This picture is a composite of Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) daily global images acquired at Ls 324o during a previous Mars year. This month, Mars looks similar, as Ls 324o occurred in mid-November 2005. The picture shows the Elysium/Mare Cimmerium face of Mars. Over the course of the month, additional faces of Mars as it appears at this time of year are being posted for MOC Picture of the Day. Ls, solar longitude, is a measure of the time of year on Mars. Mars travels 360o around the Sun in 1 Mars year. The year begins at Ls 0o, the start of northern spring and southern autumn.

Season: Northern Winter/Southern Summer

Mars at Ls 306o: Acidalia/Mare Erythraeum

NASA Technical Reports Server (NTRS)

2005-01-01

11 October 2005 This picture is a composite of Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) daily global images acquired at Ls 306o during a previous Mars year. This month, Mars looks similar, as Ls 306o occurs in mid-October 2005. The picture shows the Acidalia/Mare Erythraeum face of Mars. Over the course of the month, additional faces of Mars as it appears at this time of year are being posted for MOC Picture of the Day. Ls, solar longitude, is a measure of the time of year on Mars. Mars travels 360o around the Sun in 1 Mars year. The year begins at Ls 0o, the start of northern spring and southern autumn.

Season: Northern Winter/Southern Summer

Mars at Ls 211o: Elysium/Mare Cimmerium

NASA Technical Reports Server (NTRS)

2005-01-01

23 May 2005 This picture is a composite of Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) daily global images acquired at Ls 211o during a previous Mars year. This month, Mars looks similar, as Ls 211o occurred in mid-May 2005. The picture shows the Elysium/Mare Cimmerium face of Mars. Over the course of the month, additional faces of Mars as it appears at this time of year are being posted for MOC Picture of the Day. Ls, solar longitude, is a measure of the time of year on Mars. Mars travels 360o around the Sun in 1 Mars year. The year begins at Ls 0o, the start of northern spring and southern autumn.

Season: Northern Autumn/Southern Spring

Mars at Ls 39o: Acidalia/Mare Erythraeum

NASA Technical Reports Server (NTRS)

2006-01-01

11 April 2006 This picture is a composite of Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) daily global images acquired at Ls 39o during a previous Mars year. This month, Mars looks similar, as Ls 39o occurs in mid-April 2006. The picture shows the Acidalia/Mare Erythraeum face of Mars. Over the course of the month, additional faces of Mars as it appears at this time of year are being posted for MOC Picture of the Day. Ls, solar longitude, is a measure of the time of year on Mars. Mars travels 360o around the Sun in 1 Mars year. The year begins at Ls 0o, the start of northern spring and southern autumn.

Season: Northern Spring/Southern Autumn

Mars at Ls 341o: Elysium/Mare Cimmerium

NASA Technical Reports Server (NTRS)

2005-01-01

27 December 2005 This picture is a composite of Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) daily global images acquired at Ls 341o during a previous Mars year. This month, Mars looks similar, as Ls 341o occurred in mid-December 2005. The picture shows the Elysium/Mare Cimmerium face of Mars. Over the course of the month, additional faces of Mars as it appears at this time of year are being posted for MOC Picture of the Day. Ls, solar longitude, is a measure of the time of year on Mars. Mars travels 360o around the Sun in 1 Mars year. The year begins at Ls 0o, the start of northern spring and southern autumn.

Season: Northern Winter/Southern Summer

Mars at Ls 211o: Acidalia/Mare Erythraeum

NASA Technical Reports Server (NTRS)

2005-01-01

10 May 2005 This picture is a composite of Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) daily global images acquired at Ls 211o during a previous Mars year. This month, Mars looks similar, as Ls 211o occurs in mid-May 2005. The picture shows the Acidalia/Mare Erythraeum face of Mars. Over the course of the month, additional faces of Mars as it appears at this time of year are being posted for MOC Picture of the Day. Ls, solar longitude, is a measure of the time of year on Mars. Mars travels 360o around the Sun in 1 Mars year. The year begins at Ls 0o, the start of northern spring and southern autumn.

Season: Northern Autumn/Southern Spring

Mars at Ls 324o: Acidalia/Mare Erythraeum

NASA Technical Reports Server (NTRS)

2005-01-01

8 November 2005 This picture is a composite of Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) daily global images acquired at Ls 324o during a previous Mars year. This month, Mars looks similar, as Ls 324o occurs in mid-November 2005. The picture shows the Acidalia/Mare Erythraeum face of Mars. Over the course of the month, additional faces of Mars as it appears at this time of year are being posted for MOC Picture of the Day. Ls, solar longitude, is a measure of the time of year on Mars. Mars travels 360o around the Sun in 1 Mars year. The year begins at Ls 0o, the start of northern spring and southern autumn.

Season: Northern Winter/Southern Summer

Mars at Ls 193o: Elysium/Mare Cimmerium

NASA Technical Reports Server (NTRS)

2005-01-01

26 April 2005 This picture is a composite of Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) daily global images acquired at Ls 193o during a previous Mars year. This month, Mars looks similar, as Ls 193o occurred in mid-April 2005. The picture shows the Elysium/Mare Cimmerium face of Mars. Over the course of the month, additional faces of Mars as it appears at this time of year are being posted for MOC Picture of the Day. Ls, solar longitude, is a measure of the time of year on Mars. Mars travels 360o around the Sun in 1 Mars year. The year begins at Ls 0o, the start of northern spring and southern summer.

Season: Northern Autumn/Southern Spring

Mars at Ls 25o: Acidalia/Mare Erythraeum

NASA Technical Reports Server (NTRS)

2006-01-01

14 March 2006 This picture is a composite of Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) daily global images acquired at Ls 25o during a previous Mars year. This month, Mars looks similar, as Ls 25o occurs in mid-March 2006. The picture shows the Acidalia/Mare Erythraeum face of Mars. Over the course of the month, additional faces of Mars as it appears at this time of year are being posted for MOC Picture of the Day. Ls, solar longitude, is a measure of the time of year on Mars. Mars travels 360o around the Sun in 1 Mars year. The year begins at Ls 0o, the start of northern spring and southern autumn.

Season: Northern Spring/Southern Autumn

Mars at Ls 176o: Acidalia/Mare Erythraeum

NASA Technical Reports Server (NTRS)

2005-01-01

8 March 2005 This picture is a composite of Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) daily global images acquired at Ls 176o during a previous Mars year. This month, Mars looks similar, as Ls 176o occurs in mid-March 2005. The picture shows the Acidalia/Mare Erythraeum face of Mars. Over the course of the month, additional faces of Mars as it appears at this time of year are being posted for MOC Picture of the Day. Ls, solar longitude, is a measure of the time of year on Mars. Mars travels 360o around the Sun in 1 Mars year. The year begins at Ls 0o, the start of northern spring and southern autumn.

Season: Northern Summer/Southern Winter

Mars at Ls 288o: Elysium/Mare Cimmerium

NASA Technical Reports Server (NTRS)

2005-01-01

27 September 2005 This picture is a composite of Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) daily global images acquired at Ls 288o during a previous Mars year. This month, Mars looks similar, as Ls 288o occurred in mid-September 2005. The picture shows the Elysium/Mare Cimmerium face of Mars. Over the course of the month, additional faces of Mars as it appears at this time of year are being posted for MOC Picture of the Day. Ls, solar longitude, is a measure of the time of year on Mars. Mars travels 360o around the Sun in 1 Mars year. The year begins at Ls 0o, the start of northern spring and southern autumn.

Season: Northern Winter/Southern Summer

Mars at Ls 357o: Elysium/Mare Cimmerium

NASA Technical Reports Server (NTRS)

2006-01-01

25 January 2006 This picture is a composite of Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) daily global images acquired at Ls 357o during a previous Mars year. This month, Mars looks similar, as Ls 357o occurred in mid-January 2006. The picture shows the Elysium/Mare Cimmerium face of Mars. Over the course of the month, additional faces of Mars as it appears at this time of year are being posted for MOC Picture of the Day. Ls, solar longitude, is a measure of the time of year on Mars. Mars travels 360o around the Sun in 1 Mars year. The year begins at Ls 0o, the start of northern spring and southern autumn.

Season: Northern Winter/Southern Summer

Mars at Ls 39o: Elysium/Mare Cimmerium

NASA Technical Reports Server (NTRS)

2006-01-01

25 April 2006 This picture is a composite of Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) daily global images acquired at Ls 39o during a previous Mars year. This month, Mars looks similar, as Ls 39o occurred in mid-April 2006. The picture shows the Elysium/Mare Cimmerium face of Mars. Over the course of the month, additional faces of Mars as it appears at this time of year are being posted for MOC Picture of the Day. Ls, solar longitude, is a measure of the time of year on Mars. Mars travels 360o around the Sun in 1 Mars year. The year begins at Ls 0o, the start of northern spring and southern autumn.

Season: Northern Spring/Southern Autumn

Mars at Ls 230o: Acidalia/Mare Erythraeum

NASA Technical Reports Server (NTRS)

2005-01-01

14 June 2005 This picture is a composite of Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) daily global images acquired at Ls 230o during a previous Mars year. This month, Mars looks similar, as Ls 230o occurs in mid-June 2005. The picture shows the Acidalia/Mare Erythraeum face of Mars. Over the course of the month, additional faces of Mars as it appears at this time of year are being posted for MOC Picture of the Day. Ls, solar longitude, is a measure of the time of year on Mars. Mars travels 360o around the Sun in 1 Mars year. The year begins at Ls 0o, the start of northern spring and southern autumn.

Season: Northern Autumn/Southern Spring

Mars at Ls 269o: Acidalia/Mare Erythraeum

NASA Technical Reports Server (NTRS)

2005-01-01

9 August 2005 This picture is a composite of Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) daily global images acquired at Ls 269o during a previous Mars year. This month, Mars looks similar, as Ls 269o occurs in mid-August 2005. The picture shows the Acidalia/Mare Erythraeum face of Mars. Over the course of the month, additional faces of Mars as it appears at this time of year are being posted for MOC Picture of the Day. Ls, solar longitude, is a measure of the time of year on Mars. Mars travels 360o around the Sun in 1 Mars year. The year begins at Ls 0o, the start of northern spring and southern autumn.

Season: last days of Northern Autumn/Southern Spring

Mars at Ls 160o: Acidalia/Mare Erythraeum

NASA Technical Reports Server (NTRS)

2005-01-01

8 February 2005 This picture is a composite of Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) daily global images acquired at Ls 160o during a previous Mars year. This month, Mars looks similar, as Ls 160o occurs in mid-February 2005. The picture shows the Acidalia/Mare Erythraeum face of Mars. Over the course of the month, additional faces of Mars as it appears at this time of year are being posted for MOC Picture of the Day. Ls, solar longitude, is a measure of the time of year on Mars. Mars travels 360o around the Sun in 1 Mars year. The year begins at Ls 0o--the start of northern spring and southern summer.

Season: Northern Summer/Southern Winter

Mars at Ls 93o: Acidalia/Mare Erythraeum

NASA Technical Reports Server (NTRS)

2006-01-01

8 August 2006 This picture is a composite of Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) daily global images acquired at Ls 93o during a previous Mars year. This month, Mars looks similar, as Ls 93o occurs in mid-August 2006. The picture shows the Acidalia/Mare Erythraeum face of Mars. Over the course of the month, additional faces of Mars as it appears at this time of year are being posted for MOC Picture of the Day. Ls, solar longitude, is a measure of the time of year on Mars. Mars travels 360o around the Sun in 1 Mars year. The year begins at Ls 0o, the start of northern spring and southern autumn.

Season: Northern Summer/Southern Winter

Mars at Ls 269o: Elysium/Mare Cimmerium

NASA Technical Reports Server (NTRS)

2005-01-01

23 August 2005 This picture is a composite of Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) daily global images acquired at Ls 269o during a previous Mars year. This month, Mars looks similar, as Ls 269o occurred in mid-August 2005. The picture shows the Elysium/Mare Cimmerium face of Mars. Over the course of the month, additional faces of Mars as it appears at this time of year are being posted for MOC Picture of the Day. Ls, solar longitude, is a measure of the time of year on Mars. Mars travels 360o around the Sun in 1 Mars year. The year begins at Ls 0o, the start of northern spring and southern autumn.

Season: last days of Northern Autumn/Southern Spring

Mars at Ls 306o: Elysium/Mare Cimmerium

NASA Technical Reports Server (NTRS)

2005-01-01

25 October 2005 This picture is a composite of Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) daily global images acquired at Ls 306o during a previous Mars year. This month, Mars looks similar, as Ls 306o occurred in mid-October 2005. The picture shows the Elysium/Mare Cimmerium face of Mars. Over the course of the month, additional faces of Mars as it appears at this time of year are being posted for MOC Picture of the Day. Ls, solar longitude, is a measure of the time of year on Mars. Mars travels 360o around the Sun in 1 Mars year. The year begins at Ls 0o, the start of northern spring and southern autumn.

Season: Northern Winter/Southern Summer

Mars at Ls 79o: Elysium/Mare Cimmerium

NASA Technical Reports Server (NTRS)

2006-01-01

25 July 2006 This picture is a composite of Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) daily global images acquired at Ls 79o during a previous Mars year. This month, Mars looks similar, as Ls 79o occurred in mid-July 2006. The picture shows the Elysium/Mare Cimmerium face of Mars. Over the course of the month, additional faces of Mars as it appears at this time of year are being posted for MOC Picture of the Day. Ls, solar longitude, is a measure of the time of year on Mars. Mars travels 360o around the Sun in 1 Mars year. The year begins at Ls 0o, the start of northern spring and southern autumn.

Season: Northern Spring/Southern Autumn

Mars at Ls 107o: Acidalia/Mare Erythraeum

NASA Technical Reports Server (NTRS)

2006-01-01

13 September 2006 This picture is a composite of Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) daily global images acquired at Ls 107o during a previous Mars year. This month, Mars looks similar, as Ls 107o occurs in mid-September 2006. The picture shows the Acidalia/Mare Erythraeum face of Mars. Over the course of the month, additional faces of Mars as it appears at this time of year are being posted for MOC Picture of the Day. Ls, solar longitude, is a measure of the time of year on Mars. Mars travels 360o around the Sun in 1 Mars year. The year begins at Ls 0o, the start of northern spring and southern autumn.

Season: Northern Summer/Southern Winter

Mars at Ls 357o: Acidalia/Mare Erythraeum

NASA Technical Reports Server (NTRS)

2006-01-01

10 January 2006 This picture is a composite of Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) daily global images acquired at Ls 357o during a previous Mars year. This month, Mars looks similar, as Ls 357o occurs in mid-January 2006. The picture shows the Acidalia/Mare Erythraeum face of Mars. Over the course of the month, additional faces of Mars as it appears at this time of year are being posted for MOC Picture of the Day. Ls, solar longitude, is a measure of the time of year on Mars. Mars travels 360o around the Sun in 1 Mars year. The year begins at Ls 0o, the start of northern spring and southern autumn.

Season: Northern Winter/Southern Summer

Mars at Ls 249o: Acidalia/Mare Erythraeum

NASA Technical Reports Server (NTRS)

2005-01-01

12 July 2005 This picture is a composite of Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) daily global images acquired at Ls 249o during a previous Mars year. This month, Mars looks similar, as Ls 249o occurs in mid-July 2005. The picture shows the Acidalia/Mare Erythraeum face of Mars. Over the course of the month, additional faces of Mars as it appears at this time of year are being posted for MOC Picture of the Day. Ls, solar longitude, is a measure of the time of year on Mars. Mars travels 360o around the Sun in 1 Mars year. The year begins at Ls 0o, the start of northern spring and southern autumn.

Season: Northern Autumn/Southern Spring

Fluidized Crater Ejecta Deposit

NASA Technical Reports Server (NTRS)

1998-01-01

The Mars Orbiter Camera (MOC) onboard the Mars Global Surveyor (MGS) spacecraft continued to obtain high resolution images of the red planet into August 1998. At this time, each ground track (the portion of Mars available for MOC imaging on a given orbit) covers areas from about 40oN on the late afternoon side of the planet, up over the sunlit north polar cap, and down the early morning side of Mars to about 20oN latitude. Early morning and late afternoon views provide good shadowing to reveal subtle details on the martian surface. Views of Mars with such excellent lighting conditions will not be seen by MOC once MGS's Science Phasing Orbits end in mid-September 1998.

The image shown here, MOC image 47903, was targeted on Friday afternoon (PDT), August 7, 1998. This picture of ejecta from a nameless 9.1 kilometer (5.7 mile)-diameter crater was designed to take full advantage of the present lighting conditions. When the image was taken (around 5:38 p.m. (PDT) on Saturday, August 8, 1998), the Sun had just risen and was only about 6o above the eastern horizon. With the Sun so low in the local sky, the contrast between sunlit and shadowed surfaces allowed new, subtle details to be revealed on the surface of the crater ejecta deposit.

The crater shown here has ejecta of a type that was first identified in Mariner 9 and Viking Orbiter images as 'fluidized' ejecta. Ejecta is the material that is thrown out from the crater during the explosion that results when a meteor--piece of a comet or asteroid--collides with the planet. Fluidized ejecta is characterized by its lobate appearance, and sometimes by the presence of a ridge along the margin of the ejecta deposit. In the case of the crater shown here, there are two ridges that encircle the crater ejecta--this type of ejecta deposit is sometimes called a double-lobe rampart deposit. The MOC image shows that this particular crater also has 'normal' ejecta that occurs out on the plains, beyond the outermost ridge of the main, fluidized ejecta deposit.

Fluidized or 'rampart' ejecta deposits have long been thought by many Mars scientists to result from an impact into a surface that contains water. The water would have been underground, and could have been frozen or liquid. According to the prevailing model, when the meteor hit, this water was released--along with tons of rock and debris--and the ejecta flowed like mud. Images with resolutions higher than those presently attainable from the 11.6 hr elliptical orbit are needed to see the specific features (such as large boulders 'rafted' by the dense mud) that would confirm or refute this model. Such images may be acquired once MGS is in its mapping orbit.

MOC image 47903 was received and processed by the MOC team at Malin Space Science Systems on Monday afternoon (PDT), August 10, 1998. The image center is located at 27.92oN latitude and 184.66oW longitude, in the northern Tartarus Montes region.

Polygon-Cracked Plain

NASA Technical Reports Server (NTRS)

2005-01-01

21 July 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a polygon-cracked plain in the south polar region of Mars. When this picture was acquired in April 2005, the surface was covered with seasonal carbon dioxide frost. Dark spots and streaks indicate areas where the frost had begun to change and sublime away.

Location near: 86.8oS, 300.5oW Image width: width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Spring

Light-toned Rock Outcrop in Aureum Chaos

NASA Technical Reports Server (NTRS)

2006-01-01

30 October 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows an outcrop of light-toned, layered, sedimentary rock in Aureum Chaos. The darker material, which includes ripples, is composed of windblown sand and granules. This scene is located near 3.8oS, 26.2oW, and covers an area roughly 7.7 km by 3 km (4.8 by 1.9 mi) wide. Sunlight illuminates the terrain from the top/upper right. This southern autumn image was acquired on 14 July 2006.

South Polar Depression

NASA Technical Reports Server (NTRS)

2005-01-01

14 August 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a circular depression and a suite of eroding mesas of carbon dioxide. These features occur in the south polar residual cap of Mars. The eroding carbon dioxide creates landforms reminiscent of 'Swiss cheese.' The circular feature might indicate the location of a filled, buried impact crater.

Location near: 86.8oS, 111.0oW Image width: width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Spring

Polar Cap Retreat

NASA Technical Reports Server (NTRS)

2004-01-01

13 August 2004 This red wide angle Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a view of the retreating seasonal south polar cap in the most recent spring in late 2003. Bright areas are covered with frost, dark areas are those from which the solid carbon dioxide has sublimed away. The center of this image is located near 76.5oS, 28.2oW. The scene is large; it covers an area about 250 km (155 mi) across. The scene is illuminated by sunlight from the upper left.

Labeatis Trough

NASA Technical Reports Server (NTRS)

2006-01-01

2 July 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a portion of a trough cutting across a dust-covered plain in the Labeatis Fossae region of Mars. Boulders derived from the layered exposures near the top of the trough walls are resting on the floor, and in some locations, the sloping sidewalls of the dusty trough.

Location near: 22.1oN, 94.5oW Image width: 3 km (1.9 mi) Illumination from: lower left Season: Northern Spring

Polygons in Seasonal Frost

NASA Technical Reports Server (NTRS)

2004-01-01

8 February 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a summertime scene in the south polar region of the red planet. A patch of bright frost--possibly water ice--is seen in the lower third of the image. Polygon patterns that have developed in the ice as it sublimes away can be seen; these are not evident in the defrosted surfaces, so they are thought to have formed in the frost. This image is located near 82.6oS, 352.5oW. Sunlight illuminates this scene from the upper left; the image covers an area 3 km (1.9 mi) wide.

Landslide in Coprates

NASA Technical Reports Server (NTRS)

2004-01-01

15 November 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows the distal (far) end of a landslide deposit in Coprates Chasma, part of the vast Valles Marineris trough system. Large boulders, the size of buildings, occur on the landslide surface. This October 2004 picture is located near 15.3oS, 54.6oW, and covers an area approximately 3 km (1.9 mi) across. Sunlight illuminates the scene from the upper left.

Large Bright Ripples

NASA Technical Reports Server (NTRS)

2004-01-01

3 February 2004 Wind is the chief agent of change on Mars today. Wind blows dust and it can move coarser sediment such as sand and silt. This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows bright ripples or small dunes on the floors of troughs northeast of Isidis Planitia near 31.1oN, 244.6oW. The picture covers an area 3 km (1.9 mi) wide; sunlight illuminates the scene from the lower left.

High-resolution topomapping of candidate MER landing sites with Mars Orbiter Camera narrow-angle images

USGS Publications Warehouse

Kirk, R.L.; Howington-Kraus, E.; Redding, B.; Galuszka, D.; Hare, T.M.; Archinal, B.A.; Soderblom, L.A.; Barrett, J.M.

2003-01-01

We analyzed narrow-angle Mars Orbiter Camera (MOC-NA) images to produce high-resolution digital elevation models (DEMs) in order to provide topographic and slope information needed to assess the safety of candidate landing sites for the Mars Exploration Rovers (MER) and to assess the accuracy of our results by a variety of tests. The mapping techniques developed also support geoscientific studies and can be used with all present and planned Mars-orbiting scanner cameras. Photogrammetric analysis of MOC stereopairs yields DEMs with 3-pixel (typically 10 m) horizontal resolution, vertical precision consistent with ???0.22 pixel matching errors (typically a few meters), and slope errors of 1-3??. These DEMs are controlled to the Mars Orbiter Laser Altimeter (MOLA) global data set and consistent with it at the limits of resolution. Photoclinometry yields DEMs with single-pixel (typically ???3 m) horizontal resolution and submeter vertical precision. Where the surface albedo is uniform, the dominant error is 10-20% relative uncertainty in the amplitude of topography and slopes after "calibrating" photoclinometry against a stereo DEM to account for the influence of atmospheric haze. We mapped portions of seven candidate MER sites and the Mars Pathfinder site. Safety of the final four sites (Elysium, Gusev, Isidis, and Meridiani) was assessed by mission engineers by simulating landings on our DEMs of "hazard units" mapped in the sites, with results weighted by the probability of landing on those units; summary slope statistics show that most hazard units are smooth, with only small areas of etched terrain in Gusev crater posing a slope hazard.

Partially-Exhumed Crater in Northern Terra Meridiani: Stereo Anaglyph of overlapping coverage in

NASA Technical Reports Server (NTRS)

2002-01-01

MGS MOC Release No. MOC2-316, 8 August 2002 Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) images have shown time and again that the geology and history of Mars is complex. These two pictures show different views of a circular feature in northern Terra Meridiani at 2.3oN, 356.6oW. The first is a mosaic of 3 MOC narrow angle images acquired in August 1999, November 2000, and June 2002. The black area is a gap in coverage resulting from data lost after transmission from Mars to Earth. The second picture is a stereo ('3-D') anaglyph of a portion of the same circular feature. It has been rotated 90o clockwise to show the stereo effect that results from combining the August 1999 image, which was taken while the spacecraft was pointed nadir (straight down) and the June 2002 image, taken with the spacecraft pointing backwards about 16o (i.e., MGS Relay-16 orientation). The anaglyph should be viewed with '3-D' glasses (red in left eye, blue in the right). The circular feature was once an impact crater. The crater was 2.6 km (1.6 mi) across, about 2.6 times larger than the famous Meteor Crater in northern Arizona. Terra Meridiani, like northern Arizona, is a region of vast exposures of layered sedimentary rock. Like the crater in Arizona, this one was formed by a meteor that impacted a layered rock substrate. Later, this crater was filled and completely buried under more than 100 m (more than 327 ft) of additional layered sediment. The sediment hardened to become rock. Later still, the rock was eroded away--by processes unknown (perhaps wind)--to re-expose the buried crater. The crater today remains mostly filled with sediment, its present rim standing only about 40 m (130 ft) above its surroundings.

Flow Ejecta and Slope Landslides in Small Crater - High Resolution Image

NASA Technical Reports Server (NTRS)

1998-01-01

This high resolution picture of a moderately small impact crater on Mars was taken by the Mars Global Surveyor Orbiter Camera (MOC) on October 17, 1997 at 4:11:07 PM PST, during MGS orbit 22. The image covers an area 2.9 by 48.4 kilometers (1.8 by 30 miles) at 9.6 m (31.5 feet) per picture element, and is centered at 21.3 degrees N, 179.8 degrees W, near Orcus Patera. The MOC image is a factor of 15X better than pervious Viking views of this particular crater.

The unnamed crater is one of three closely adjacent impact features that display the ejecta pattern characteristic of one type of 'flow-ejecta' crater. Such patterns are considered evidence of fluidized movement of the materials ejected during the cratering event, and are believed to indicate the presence of subsurface ice or liquid water.

Long, linear features of different brightness values can be seen on the on the steep slopes inside and outside the crater rim. This type of feature, first identified in Viking Orbiter images acquired over 20 years ago, are more clearly seen in this new view (about 3 times better than the best previous observations). Their most likely explanation is that small land or dirt slides, initiated by seismic or wind action, have flowed down the steep slopes. Initially dark because of the nature of the surface disturbance, these features get lighter with time as the ubiquitous fine, bright dust settles onto them from the martian atmosphere. Based on estimates of the dust fall-out rate, many of these features are probably only a few tens to hundreds of years old. Thus, they are evidence of a process that is active on Mars today.

Malin Space Science Systems (MSSS) and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

Flow Ejecta and Slope Landslides in Small Crater

NASA Technical Reports Server (NTRS)

1998-01-01

This high resolution picture of a moderately small impact crater on Mars was taken by the Mars Global Surveyor Orbiter Camera (MOC) on October 17, 1997 at 4:11:07 PM PST, during MGS orbit 22. The image covers an area 2.9 by 48.4 kilometers (1.8 by 30 miles) at 9.6 m (31.5 feet) per picture element, and is centered at 21.3 degrees N, 179.8 degrees W, near Orcus Patera. The MOC image is a factor of 15X better than pervious Viking views of this particular crater (left, Viking image 545A49).

The unnamed crater is one of three closely adjacent impact features that display the ejecta pattern characteristic of one type of 'flow-ejecta' crater. Such patterns are considered evidence of fluidized movement of the materials ejected during the cratering event, and are believed to indicate the presence of subsurface ice or liquid water.

Long, linear features of different brightness values can be seen on the on the steep slopes inside and outside the crater rim. This type of feature, first identified in Viking Orbiter images acquired over 20 years ago, are more clearly seen in this new view (about 3 times better than the best previous observations). Their most likely explanation is that small land or dirt slides, initiated by seismic or wind action, have flowed down the steep slopes. Initially dark because of the nature of the surface disturbance, these features get lighter with time as the ubiquitous fine, bright dust settles onto them from the martian atmosphere. Based on estimates of the dust fall-out rate, many of these features are probably only a few tens to hundreds of years old. Thus, they are evidence of a process that is active on Mars today.

Malin Space Science Systems (MSSS) and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

Mars at Ls 107o: Elysium/Mare Cimmerium

NASA Technical Reports Server (NTRS)

2006-01-01

26 September 2006 This picture is a composite of Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) daily global images acquired at L_s 107o during a previous Mars year. This month, Mars looks similar, as L_s 107o occurred in mid-September 2006. The picture shows the Elysium/Mare Cimmerium face of Mars. Over the course of the month, additional faces of Mars as it appears at this time of year are being posted for MOC Picture of the Day. L_s, solar longitude, is a measure of the time of year on Mars. Mars travels 360o around the Sun in 1 Mars year. The year begins at L_s 0o, the start of northern spring and southern autumn.

Season: Northern Summer/Southern Winter

Ripples and Dunes

NASA Technical Reports Server (NTRS)

2006-01-01

27 May 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows dark sand dunes on the floor of an impact crater west of Hellas Planitia. Portions of the crater floor are exposed near the center and lower right corner of the image but, in general, the floor is covered by large, windblown ripples. The dark dune sand typically covers ripples, indicating that the dunes are younger and made of a more mobile material.

Location near: 43.7oS, 320.4oW Image width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Summer

Small Landslide in Kasei

NASA Technical Reports Server (NTRS)

2004-01-01

21 February 2004 The finger-shaped lobe just right of center in this Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image is the deposit of a small landslide that came down a dark, layered slope. Landslides are common on Mars in areas of steep topography; this one is located in the Kasei Valles region near 23.9oN, 67.1oW. Sunlight illuminates the scene from the lower left; the picture covers an area 3 km (1.9 mi) wide.

Sand Dunes with Frost

NASA Technical Reports Server (NTRS)

2004-01-01

9 May 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a suite of frost-covered sand dunes in the north polar region of Mars in early spring, 2004. The dunes indicate wind transport of sand from left to right (west to east). These landforms are located near 78.1oN, 220.8oW. This picture is illuminated by sunlight from the lower left and covers an area about 3 km (1.9 mi) across.

MRO Mars Color Imager (MARCI) Investigation Primary Mission Results

NASA Astrophysics Data System (ADS)

Edgett, K. S.; Cantor, B. A.; Malin, M. C.; Science; Operations Teams, M.

2008-12-01

The Mars Reconnaissance Orbiter (MRO) Mars Color Imager (MARCI) investigation was designed to recover the wide angle camera science objectives of the Mars Climate Orbiter MARCI which was destroyed upon arrival at Mars in 1999 and extend the daily meteorological coverage of the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) wide angle investigation that was systematically conducted from March 1999 to October 2006. MARCI consists of two wide angle cameras, each with a 180° field of view. The first acquires data in 5 visible wavelength channels (420, 550, 600, 650, 720 nm), the second in 2 UV channels (260, 320 nm). Data have been acquired daily, except during spacecraft upsets, since 24 September 2006. From the MRO 250 to 315 km altitude orbit, inclined 93 degrees, visible wavelength images usually have a pixel scale of about 1 km at nadir and the UV data are at about 8 km per pixel. Data are obtained during every orbit on the day side of the planet from terminator to terminator. These provide a nearly continuous record of meteorological events and changes in surface frost and albedo patterns that span more than 1 martian year and extend the daily global record of such events documented by the MGS MOC. For a few weeks in September and October 2006, both camera systems operated simultaneously, providing views of weather events at about 1400 local time (MOC) and an hour later at about 1500 (MARCI). The continuous meteorological record, now spanning more than 5 Mars years, shows very repeatable weather from year to year with cloud and dust-raising events occurring in the same regions within about 2 weeks of their prior occurrence in previous years. This provides a measure of predictability ideal for assessing future landing sites, orbiter aerobraking plans, and conditions to be encountered by the current landed spacecraft on Mars. However, less predictable are planet-encircling dust events. MOC observed one in 2001, the next was observed by MARCI in 2007. These occurred at different times of year. While popularly known as global dust storms, the nomenclature is misleading, as in each case a storm did not raise dust nor saltate sand on a global basis. Instead, multiple regional storms created a dust haze which obscured much of the martian surface from viewpoints above the lower atmosphere, but in each case the dust opacity was never so high that one could not determine where dust was being raised and where it was not. Within weeks of the end of the 2001 and 2007 global dust events, martian weather returned to its normal, repeatable pattern, with one exception: occasionally thereafter, dust storms were observed in regions where dust-raising had not been seen in the previous years. In these cases, winds capable of raising dust likely occurred at that location every year, but only became visible following a planet-encircling dust event and deposition of dust on a surface that previously did not have sufficient dust to raise. Other MARCI results center on seasonal monitoring of water vapor in the atmosphere, particularly by taking advantage of the anti-correlation between ozone (observable using the UV channels) and water vapor. Owing to their higher spatial resolution than the MOC daily global coverage, details of seasonal polar cap retreat became more apparent, as with these data it is now possible to separate surface frost from ground-hugging fog which forms along the retreating cap edge. MARCI images and meteorological observations are posted weekly on the Internet for public consumption, and the data are archived every 6 months with the NASA Planetary Data System.

Eos Chaos Rocks

NASA Technical Reports Server (NTRS)

2006-01-01

11 January 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows light-toned, layered rock outcrops in Eos Chaos, located near the east end of the Valles Marineris trough system. The outcrops occur in the form of a distinct, circular butte (upper half of image) and a high slope (lower half of image). The rocks might be sedimentary rocks, similar to those found elsewhere exposed in the Valles Marineris system and the chaotic terrain to the east of the region.

Location near: 12.9oS, 49.5oW Image width: 3 km (1.9 mi) Illumination from: lower left Season: Southern Summer

Pits on Ascraeus

NASA Technical Reports Server (NTRS)

2005-01-01

24 September 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows collapse pits and troughs on the lower northeast flank of the giant martian volcano, Ascraeus Mons. Layers of volcanic rock are evident in some of the pit and valley walls, and boulders the size of houses and trucks that were liberated from these walls by gravity can be seen on the floors of the depressions.

Location near: 13.6oN, 102.6oW Image width: width: 3 km (1.9 mi) Illumination from: lower left Season: Northern Autumn

Polygons and Craters

NASA Technical Reports Server (NTRS)

2005-01-01

3 September 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows polygons enhanced by subliming seasonal frost in the martian south polar region. Polygons similar to these occur in frozen ground at high latitudes on Earth, suggesting that perhaps their presence on Mars is also a sign that there is or once was ice in the shallow subsurface. The circular features are degraded meteor impact craters.

Location near: 72.2oS, 310.3oW Image width: width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Spring

Defrosting Spots

NASA Technical Reports Server (NTRS)

2005-01-01

3 October 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows dark, defrosting spots formed on a polygon-cracked plain in the south polar region of Mars. The surface was covered with carbon dioxide frost during the previous winter. In spring, the material begins to sublime away, creating a pattern of dark spots that sometimes have wind streaks emanating from them, as wind carries away or erodes the frost.

Location near: 87.2oS, 28.4oW Image width: width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Spring

Memnonia Landscape

NASA Technical Reports Server (NTRS)

2006-01-01

28 June 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a contact between a dust-covered plain and a dust-mantled, textured upland in the Memnonia Sulci region of Mars. The dominant landforms in this scene are yardangs-they are the product of extensive wind erosion of a relatively poorly-consolidated, sand-bearing material (e.g., deposits of volcanic ash or poorly cemented sedimentary rocks).

Location near: 9.3oS, 172.9oW Image width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Autumn

Side-by-Side

NASA Technical Reports Server (NTRS)

2006-01-01

18 May 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows neighboring networks of gullies in the northwest wall of a south middle-latitude crater west of Hellas Planitia. The faint crisscrossing streaks, also observed on the wall of the crater, are evidence of passing dust devils, a common phenomenon in this region. The gullies might have formed by erosion caused by running water, mixed with debris.

Location near: 16.4oN, 92.6oW Image width: 3 km (1.9 mi) Illumination from: lower left Season: Northern Winter

Bits and Pieces

NASA Technical Reports Server (NTRS)

2006-01-01

19 August 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows the contact between an area of light-toned rock and an expanse of darker-toned materials on the floor of Coprates Chasma. Remnants -- bits and pieces -- of the light-toned material are scattered throughout the scene, indicating that this material once covered everything in this area. Coprates is one of several chasms that comprise the giant Valles Marineris trough system.

Location near: 13.2oS, 61.8oW Image width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Autumn

North Polar Cap

NASA Technical Reports Server (NTRS)

2004-01-01

7 September 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a 1.4 m/pixel (5 ft/pixel) view of a typical martian north polar ice cap texture. The surface is pitted and rough at the scale of several meters. The north polar residual cap of Mars consists mainly of water ice, while the south polar residual cap is mostly carbon dioxide. This picture is located near 85.2oN, 283.2oW. The image covers an area approximately 1 km wide by 1.4 km high (0.62 by 0.87 miles). Sunlight illuminates this scene from the lower left.

South Mid-latitude Gullies

NASA Technical Reports Server (NTRS)

2005-01-01

19 November 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows deep gullies cut into the wall of a south mid-latitude crater. Erosion has exposed layers in the upper wall of the crater; it is possible that groundwater seeping through a layer or layers in the wall led to the genesis of the gullies. The banked nature of the gully channels suggests that a liquid was involved.

Location near: 35.5oS, 194.8oW Image width: width: 2 km (1.2 mi) Illumination from: upper left Season: Southern Spring

Cracky Mars

NASA Technical Reports Server (NTRS)

2006-01-01

21 September 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows cracked, layered plains-forming material in the western part of Utopia Planitia, Mars. Investigators have speculated that ice might be -- or might once have been -- present in the ground, and changes in temperature and the amount of ice over time may have led to the formation of these cracks. But no one is certain just how these features formed.

Location near: 45.0oN, 276.1oW Image width: 3 km (1.9 mi) Illumination from: lower left Season: Northern Spring

Gullied Depression

NASA Technical Reports Server (NTRS)

2006-01-01

26 February 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows gullies formed in the wall of a depression located on the floor of Rabe Crater west of the giant impact basin, Hellas Planitia. Gullies such as these are common features on Mars, but the process by which they are formed is not fully understood. The debate centers on the role and source of fluids in the genesis of these features.

Location near: 44.1oS, 325.9oW Image width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Summer

Out of Steam

NASA Technical Reports Server (NTRS)

2006-01-01

16 April 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows the margin of an ancient, cratered, hummocky (rough) lava flow at just the point where it encroached upon a small impact crater east of the volcano, Tharsis Tholus. The lava flow was thin enough and didn't have sufficient energy to flow into and bury the crater. Instead, it took the path of least of resistance, around the crater.

Location near: 85.5oS, 76.8oW Image width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Summer

Ultrahigh resolution topographic mapping of Mars with MRO HiRISE stereo images: Meter-scale slopes of candidate Phoenix landing sites

USGS Publications Warehouse

Kirk, R.L.; Howington-Kraus, E.; Rosiek, M.R.; Anderson, J.A.; Archinal, B.A.; Becker, K.J.; Cook, D.A.; Galuszka, D.M.; Geissler, P.E.; Hare, T.M.; Holmberg, I.M.; Keszthelyi, L.P.; Redding, B.L.; Delamere, W.A.; Gallagher, D.; Chapel, J.D.; Eliason, E.M.; King, R.; McEwen, A.S.

2009-01-01

The objectives of this paper are twofold: first, to report our estimates of the meter-to-decameter-scale topography and slopes of candidate landing sites for the Phoenix mission, based on analysis of Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) images with a typical pixel scale of 3 m and Mars Reconnaissance Orbiter (MRO) High Resolution Imaging Science Experiment (HiRISE) images at 0.3 m pixel-1 and, second, to document in detail the geometric calibration, software, and procedures on which the photogrammetric analysis of HiRISE data is based. A combination of optical design modeling, laboratory observations, star images, and Mars images form the basis for software in the U.S. Geological Survey Integrated Software for Imagers and Spectrometers (ISIS) 3 system that corrects the images for a variety of distortions with single-pixel or subpixel accuracy. Corrected images are analyzed in the commercial photogrammetric software SOCET SET (??BAE Systems), yielding digital topographic models (DTMs) with a grid spacing of 1 m (3-4 pixels) that require minimal interactive editing. Photoclinometry yields DTMs with single-pixel grid spacing. Slopes from MOC and HiRISE are comparable throughout the latitude zone of interest and compare favorably with those where past missions have landed successfully; only the Mars Exploration Rover (MER) B site in Meridiani Planum is smoother. MOC results at multiple locations have root-mean-square (RMS) bidirectional slopes of 0.8-4.5?? at baselines of 3-10 m. HiRISE stereopairs (one per final candidate site and one in the former site) yield 1.8-2.8?? slopes at 1-m baseline. Slopes at 1 m from photoclinometry are also in the range 2-3?? after correction for image blur. Slopes exceeding the 16?? Phoenix safety limit are extremely rare. Copyright 2008 by the American Geophysical Union.

Layers and a Dust Devil in Melas Chasma

NASA Technical Reports Server (NTRS)

2000-01-01

One of the earliest observations made by the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) was that the upper crust of the planet appears to be layered to considerable depth. This was especially apparent, early in the mission, in the walls of the Valles Marineris chasms. However, layered mesas and mounds within the Valles Marineris troughs were recognized all the way back in 1972 with Mariner 9 images. The MOC image presented here shows many tens of layers of several meters (yards) thickness in the walls of a mesa in southern Melas Chasma in Valles Marineris. Erosion by mass wasting--landslides--has exposed these layers and created the dark fan-shaped deposits seen near the middle of the image. The floor of Melas Chasma is dark and covered with many parallel ridges and grooves (lower 1/3 of image). In the lower left corner of the picture, a bright, circular dust devil can be seen casting a columnar shadow toward the left. This image, illuminated by sunlight from the right/lower right, covers an area 3 kilometers (1.9 miles) wide and 8.2 kilometers (5.1 miles) long. The scene is located near 10.1oS, 74.4oW and was acquired on July 11, 1999. North is toward the lower left.

SUV Tracks On Mars? The 'Devil' is in the Details

NASA Technical Reports Server (NTRS)

1998-01-01

Sport Utility Vehicles (SUVs) on Mars? Imagine the MOC imaging team's surprise on the morning of April 27, 1998, as the latest images came in from the 'Red Planet.'

A picture taken by the camera on Mars Global Surveyor just one day earlier showed several thin, dark lines that--at first glance--looked like pathways blazed by off-road sport utility vehicles. Who's been driving around on Mars?

The MOC image in question (#26403), seen here at full resolution of 13.8 meters (45 feet) per pixel, was obtained around 10:22 a.m. PDT on April 26, 1998, during Mars Global Surveyor's 264th orbit. North is approximately up, illumination is from the lower right. Located in eastern Arabia Terra near 16.5o N latitude, 311.4o W longitude, the image showed a number of natural features--small craters formed by meteor impact, several buttes and mesas left by erosion of the surrounding terrain, small dunes and drifts, and a mantle of dust that varies in thickness from place to place. But the new picture also showed two dark lines--each varying in width up to about 15 meters (49 feet)--that extended several kilometers/miles across the image.

Lines like these have been seen before on Mars. They are most likely the result of dust devils--columnar vortices of wind that move across the landscape, pick up dust, and look somewhat like miniature tornadoes. Dust devils are a common occurrence in dry and desert landscapes on Earth as well as Mars. They form when the ground heats up during the day, warming the air immediately above the surface. As pockets of warm air rise and interfere with one another, they create horizontal pressure variations that, combined with other meteorological winds, cause the upward moving air to spin (the direction of the spin is controlled by the same Coriolis forces that cause terrestrial hurricanes to spin in specific directions). As the spinning column of air moves across the surface, it occasionally encounters dust on the surface, which it can suck upward. This dust rises into the spinning air, giving the appearance of a tornado-like column that moves across the landscape. As the column of air moves, its ability to pick up dust varies--sometimes they hold a lot of dust and are nearly opaque; sometimes you cannot even see them. Dust-devils rarely last long, since their very motion changes the conditions that allowed them to form in the first place.

Mars Pathfinder detected the passage of several dust devils during its 83 days of operation on Mars in 1997. Mariner 9 and the Viking landers and orbiters of the 1970s also found evidence that dust devils occur on Mars; indeed, some Viking Orbiter images actually show dust devil clouds. MOC image 26403 is the latest entry in the body of evidence for the work of wind in the modern martian environment. The MOC Science Team is continuing to study these and other streaks caused by wind interacting with the martian surface.

Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

Landslide in Aureum Chaos

NASA Technical Reports Server (NTRS)

2004-01-01

15 May 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows the results of a small landslide off of a hillslope in the Aureum Chaos region of Mars. Mass movement occurred from right (the slope) to left (the lobate feature pointed left). Small dark dots in the landslide area are large boulders. This feature is located near 2.6oS, 24.5oW. This picture covers an area approximately 3 km (1.9 mi) across and is illuminated by sunlight from the left/upper left.

Sedimentary Rocks of Aram Chaos

NASA Technical Reports Server (NTRS)

2004-01-01

4 February 2004 Aram Chaos is a large meteor impact crater that was nearly filled with sediment. Over time, this sediment was hardened to form sedimentary rock. Today, much of the eastern half of the crater has exposures of light-toned sedimentary rock, such as the outcrops shown in this Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image. The picture is located near 2.0oN, 20.3oW, and covers an area 3 km (1.9 mi) wide. Sunlight illuminates the scene from the left.

Dune and Dust Devil Tracks

NASA Technical Reports Server (NTRS)

2004-01-01

31 January 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a dark sand dune patch that occurs on the floor of a southern hemisphere crater near 64.1oS, 197.2oW. Passing dust devils have disrupted the fine, bright dust that coats the surrounding terrain, leaving wildly-varied streak patterns. Dark dots to the left (west) of the dune are boulders. The picture covers an area 3 km (1.9 mi) wide; sunlight illuminates the scene from the upper left.

Winter Frost and Fog

NASA Technical Reports Server (NTRS)

2005-01-01

This somewhat oblique blue wide angle Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows the 174 km (108 mi) diameter crater, Terby, and its vicinity in December 2004. Located north of Hellas, this region can be covered with seasonal frost and ground-hugging fog, even in the afternoon, despite being north of 30oS. The subtle, wavy pattern is a manifestation of fog.

Location near: 28oS, 286oW Illumination from: upper left Season: Southern Winter

Mars at Ls 137o

NASA Technical Reports Server (NTRS)

2006-01-01

13 November 2006 These images capture what Mars typically looks like in mid-afternoon at L_s 137o. In other words, with the exception of occasional differences in weather and polar frost patterns, this is what the red planet looks like this month (November 2006).

Six views are shown, including the two polar regions. These are composites of 24-26 Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) daily global mapping images acquired at red and blue wavelengths. The 'hole' over the south pole is an area where no images were obtained, because this polar region is enveloped in wintertime darkness.

Presently, it is summer in the northern hemisphere and winter in the southern hemisphere. Ls, solar longitude, is a measure of the time of year on Mars. Mars travels 360o around the Sun in 1 Mars year. The year begins at Ls 0o, the start of northern spring and southern autumn. Northern summer/southern winter begins at Ls 90o, northern autumn/southern spring start at Ls 180o, and northern winter/southern summer begin at Ls 270o.

L_s 137o occurs in the middle of this month (November 2006). The pictures show how Mars appeared to the MOC wide angle cameras at a previous Ls 137o in March 2001. The six views are centered on the Tharsis region (upper left), Acidalia and Mare Eyrthraeum (upper right), Syrtis Major and Hellas (middle left), Elysium and Mare Cimmeria (middle right), the north pole (lower left), and the south pole (lower right).

South Polar Cap Erosion and Aprons

NASA Technical Reports Server (NTRS)

2000-01-01

This scene is illuminated by sunlight from the upper left.

While Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) images have shown that the north and south polar cap surfaces are very different from each other, one thing that the two have in common is that they both seem to have been eroded. Erosion in the north appears mostly to come in the form of pits from which ice probably sublimed to vapor and was transported away from the polar cap by wind. Erosion in the south takes on a wider range of possible processes that include collapse, slumping and mass-movement on slopes, and probably sublimation. Among the landforms created by these process on the south polar cap are the 'aprons' that surround mesas and buttes of remnant layers such as the two almost triangular features in the lower quarter of this image. The upper slopes of the two triangular features show a stair-stepped pattern that suggest these hills are layered.

This image shows part of the south polar residual cap near 86.9oS, 78.5oW, and covers an area approximately 1.2 by 1.0 kilometers (0.7 x 0.6 miles) in size. The image has a resolution of 2.2 meters per pixel. The picture was taken on September 11, 1999.

Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

MRO Context Camera (CTX) Investigation Primary Mission Results

NASA Astrophysics Data System (ADS)

Edgett, K. S.; Malin, M. C.; Science; Operations Teams, M.

2008-12-01

The Mars Reconnaissance Orbiter (MRO) Context Camera (CTX) acquires panchromatic images of Mars at ~6 m/pixel; the majority cover areas 30 km wide by 43 to 313 km long. As of 31 August 2008, 36% of Mars was imaged at 6 m/pixel and 10.8% was covered more than once. Areas imaged multiple times include stereopairs and locations covered repeatedly to monitor dust-raising events, seasonal frost patterns, or landforms and albedo features known or anticipated to change. CTX provides context for data acquired by other MRO science instruments, as well. Using our knowledge of imaging performance as a function of seasonal atmospheric, frost, and insolation conditions from the 4 Mars-year Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) investigation, we undertook several time-dependent campaigns to create 6 m/pixel mosaics of regions such as Hellas Planitia, the south polar residual cap (covered in spring and in summer), and the north polar region. In addition, we obtained 6 m/pixel mosaics of the Valles Marineris, Sinus Meridiani, Marte Valles, Athabasca Valles, portions of the northern plains, fretted terrain and chaotic terrain, large volcanoes, yardang-forming materials in Amazonis and Aeolis, the small volcanoes and platy flows south of Cerberus, and many other regions. We monitored thousands of mid-latitude gullies, and we used our MOC experience to target dust-raising events that repeat every year at the same locations. Retreat of cliffs formed in layers of CO2 ice in the south polar cap was observed for the 5th southern summer since 1999. Dozens of new impact craters and crater clusters were observed; all formed since 1999 and some formed during the MRO Primary Mission. We routinely re-targeted the new impact sites to see how they change and alert other MRO instrument teams so they could observe them. CTX images of the cratered highlands emphasize the view that the upper crust of Mars is layered with interbedded filled and buried valleys, fluvial channels, and impact craters ranging in diameter from meters to hundreds of kilometers. CTX observations reiterate a critical MOC result regarding small, sub-kilometer diameter craters: the substrates most resistant to erosion retain the most small craters (and the boulders produced by the impacts). CTX images provide many examples in which a younger, harder substrate (e.g., a lava flow) is more heavily cratered (with < 1 km diameter craters) than subjacent, older rock units. One example occurs in the form of lava flows located immediately west of Meridiani Planum; similar flows underlie the hematite-bearing, plains- forming rock in nearby Miyamoto Crater. Northern Meridiani also exhibits exhumed, low-order streams (of the scale of hillslope rills and creeks); these were filled, buried, lithified, and later returned to the surface by erosion-some of them in inverted form. Terrain immediately west of Juventae Chasma exhibits similar inverted streams and rills that were first documented by MOC and provide key evidence for rainfall and hillslope runoff. CTX data show that there are many hundreds of inverted fluvial channels, of a variety of sizes, all over the planet, especially in Arabia Terra, Solis Planum, and Thaumasia. We also used CTX to map a small, unnamed outflow channel system west of Bond Crater, and we have been documenting all of the small Martian volcanoes, typically < 30 km across, including those occurring in the Labyrinthus Noctis. CTX data are widely available, as they are archived with the NASA Planetary Data System on a rolling basis every 6 months.

Martian 'Kitchen Sponge'

NASA Technical Reports Server (NTRS)

2000-01-01

This picture is illuminated by sunlight from the upper left. It shows a tiny 1 kilometer by 1 kilometer (0.62 x 0.62 mile) area of the martian north polar residual ice cap as it appears in summertime.

The surface looks somewhat like that of a kitchen sponge--it is flat on top and has many closely-spaced pits of no more than 2 meters (5.5 ft) depth. The upper, flat surface in this image has a medium-gray tone, while the pit interiors are darker gray. Each pit is generally 10 to 20 meters (33-66 feet) across. The pits probably form as water ice sublimes--going directly from solid to vapor--during the martian northern summer seasons. The pits probably develop over thousands of years. This texture is very different from what is seen in the south polar cap, where considerably larger and more circular depressions are found to resemble slices of swiss cheese rather than a kitchen sponge.

This picture was taken by the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) during northern summer on March 8, 1999. It was one of the very last 'calibration' images taken before the start of the Mapping Phase of the MGS mission, and its goal was to determine whether the MOC was properly focused. The crisp appearance of the edges of the pits confirmed that the instrument was focused and ready for its 1-Mars Year mapping mission. The scene is located near 86.9oN, 207.5oW, and has a resolution of about 1.4 meters (4 ft, 7 in) per pixel.

Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

Meter-Scale 3-D Models of the Martian Surface from Combining MOC and MOLA Data

NASA Technical Reports Server (NTRS)

Soderblom, Laurence A.; Kirk, Randolph L.

2003-01-01

We have extended our previous efforts to derive through controlled photoclinometry, accurate, calibrated, high-resolution topographic models of the martian surface. The process involves combining MGS MOLA topographic profiles and MGS MOC Narrow Angle images. The earlier work utilized, along with a particular MOC NA image, the MOLA topographic profile that was acquired simultaneously, in order to derive photometric and scattering properties of the surface and atmosphere so as to force the low spatial frequencies of a one-dimensional MOC photoclinometric model to match the MOLA profile. Both that work and the new results reported here depend heavily on successful efforts to: 1) refine the radiometric calibration of MOC NA; 2) register the MOC to MOLA coordinate systems and refine the pointing; and 3) provide the ability to project into a common coordinate system, simultaneously acquired MOC and MOLA with a single set of SPICE kernels utilizing the USGS ISIS cartographic image processing tools. The approach described in this paper extends the MOC-MOLA integration and cross-calibration procedures from one-dimensional profiles to full two-dimensional photoclinometry and image simulations. Included are methods to account for low-frequency albedo variations within the scene.

Athabasca Vallis Streamlined 'Islands'

NASA Technical Reports Server (NTRS)

2002-01-01

MGS MOC Release No. MOC2-322, 12 December 2002

Tremendous floods carved these tear drop-shaped landforms in Athabasca Vallis in the Cerberus region, south of the Elysium volcanoes. The orientation of the streamlined forms indicate that the fluid flowed from the right/upper right toward the left/lower left (from the northeast to the southwest). Similar features occur in central and eastern Washington in the northwestern United States. The examples in Washington formed when massive amounts of water rushed across the landscape, scouring a 'channeled scabland' during the last Ice Age, roughly 12,000-13,000 years ago. The features on Mars are much older; while the absolute age cannot be determined, the small impact craters with rayed ejecta patterns on the flood surfaces indicate it must be much, much older than the flood landscape in Washington. This is a mosaic of six Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) images acquired in 1999 through 2002. Illumination is from the left. The mosaic covers an area 11.9 km (7.4 mi) by 13.0 km (8.1 mi). The full-size mosaic has a resolution of 4 meters (13 ft) per pixel.

Windblown Dunes and Ripples

NASA Technical Reports Server (NTRS)

2003-01-01

MGS MOC Release No. MOC2-411, 4 July 2003

July 4, 2003, is the 6th anniversary of the Mars Pathfinder landing. One of the elements carried to the red planet by Pathfinder was the Wind Sock Experiment. This project was designed to measure wind activity by taking pictures of three aluminum 'wind socks.' While the winds at the Mars Pathfinder site did not blow particularly strong during the course of that mission, dust storms seen from orbit and Earth-based telescopes attest to the fact that wind is a major force of change on the dry, desert surface of Mars today. This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) narrow angle image shows dark sand dunes and lighter-toned ripples trapped among the mountainous central peak of an old impact crater in Terra Tyrrhena near 13.9oS, 246.7oW. The dune slip faces--the steepest slope on the larger dunes--indicate sand transport is from the top/upper left toward the bottom/lower right. North is toward the top/upper right; the picture is 3 km (1.9 mi) across. Sunlight illuminates the scene from the upper left. This picture was obtained in April 2003.

Sand Dunes of Nili Patera in 3-D

NASA Technical Reports Server (NTRS)

2001-01-01

The most exciting new aspect of the Mars Global Surveyor (MGS) Extended Mission is the opportunity to turn the spacecraft and point the Mars Orbiter Camera (MOC) at specific features of interest. Opportunities to point the spacecraft come about ten times a week. Throughout the Primary Mission (March 1999 - January 2001), nearly all MGS operations were conducted with the spacecraft pointing 'nadir'--that is, straight down. A search for the missing Mars Polar Lander in late 1999 and early 2000 demonstrated that pointing the spacecraft could allow opportunities for MOC to see things that simply had not entered its field of view during typical nadir-looking operations, and to target areas previously seen in a nadir view so that stereo ('3-D') pictures could be derived.

One of the very first places photographed by the MOC at the start of the Mapping Mission in March 1999 was a field of dunes located in Nili Patera, a volcanic depression in central Syrtis Major. A portion of this dune field was shown in a media release on March 11, 1999, 'Sand Dunes of Nili Patera, Syrtis Major'. Subsequently, the image was archived with the NASA Planetary Data System, as shown in the Malin Space Science Systems MOC Gallery. On April 24, 2001, an opportunity arose in which the MGS could be pointed off-nadir to take a new picture of the same dune field. By combining the nadir view from March 1999 and the off-nadir view from April 2001, a stereoscopic image was created. The anaglyph shown here must be viewed with red (left-eye) and blue (right-eye) '3-D' glasses. The dunes and the local topography of the volcanic crater's floor stand out in sharp relief. The images, taken more than one Mars year apart, show no change in the shape or location of the dunes--that is, they do not seem to have moved at all since March 1999.

Residual Cap

NASA Technical Reports Server (NTRS)

2006-01-01

10 May 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a summertime view of the south polar residual cap of Mars. In this image, mesas composed largely of solid carbon dioxide are separated from one another by irregularly-shaped depressions. The variation in brightness across this scene is a function of several factors including, but not limited to, varying proportions of dust and solid carbon dioxide, undulating topography, and differences in the roughness of the slopes versus the flat surfaces.

Location near: 86.7oS, 343.3oW Image width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Summer

A Few Good Barchans

NASA Technical Reports Server (NTRS)

2006-01-01

This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows several small, dark sand dunes and a small crater (about 1 kilometer in diameter) within a much larger crater (not visible in this image). The floor of the larger crater is rough and has been eroded with time. The floor of the smaller crater contains windblown ripples. The steep faces of the dunes point to the east (right), indicating that the dominant winds blew from the west (left). This scene is located near 38.5 S, 347.1 W, and covers an area approximately 3 km (1.9 mi) wide. Sunlight illuminates the landscape from the upper left. This southern autumn image was acquired on 1 July 2006.

Northeast Arabia Terra

NASA Technical Reports Server (NTRS)

2004-01-01

9 September 2004 Northeastern Arabia Terra is a heavily eroded portion of the martian cratered highlands. Layered rock, containing filled and buried valleys and ancient impact craters, has been eroded such that these once-buried features are now partially exposed at the martian surface. This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows an example of a field of circular and somewhat circular features that once were impact craters that were subsequently filled, buried, then exhumed to form the patterns exhibited here. The image is located near 25.6oN, 290.2oW. The image covers an area approximately 3 km (1.9 mi) across and is illuminated by sunlight from the lower left.

Public-Requested Mars Image: Crater on Pavonis Mons

NASA Technical Reports Server (NTRS)

2003-01-01

MGS MOC Release No. MOC2-481, 12 September 2003

This image is in the first pair obtained in the Public Target Request program, which accepts suggestions for sites to photograph with the Mars Orbiter Camera on NASA's Mars Global Surveyor spacecraft.

It is a narrow-angle (high-resolution) view of a portion of the lower wall and floor of the caldera at the top of a martian volcano named Pavonis Mons. A companion picture is a wide-angle context image, taken at the same time as the high-resolution view. The white box in the context frame shows the location of the high-resolution picture.

[figure removed for brevity, see original site]

Pavonis Mons is a broad shield volcano. Its summit region is about 14 kilometers (8.7 miles) above the martian datum (zero-elevation reference level). The caldera is about 4.6 kilometers (2.8 miles) deep. The caldera formed by collapse--long ago--as molten rock withdrew to greater depths within the volcano. The high-resolution picture shows that today the floor and walls of this caldera are covered by a thick, textured mantle of dust, perhaps more than 1 meter (1 yard) deep. Larger boulders and rock outcroppings poke out from within this dust mantle. They are seen as small, dark dots and mounds on the lower slopes of the wall in the high-resolution image.

The narrow-angle Mars Orbiter Camera image has a resolution of 1.5 meters (about 5 feet) per pixel and covers an area 1.5 kilometers (0.9 mile) wide by 9 kilometers (5.6 miles) long. The context image, covering much of the summit region of Pavonis Mons, is about 115 kilometers (72 miles) wide. Sunlight illuminates both images from the lower left; north is toward the upper right; east to the right. The high-resolution view is located near 0.4 degrees north latitude, 112.8 degrees west longitude.

Marte Vallis Channel

NASA Technical Reports Server (NTRS)

2004-01-01

14 September 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a portion of a channel in the Marte Valles outflow system. An old meteor impact crater in the lower left (southwest) corner of the image blocked the erosive fluids that poured through Marte Vallis, creating a streamlined tail in its lee. The materials that flowed through the valley may have been water-rich mud, very fluid lava, or both. The nature of the fluid is still a matter of research and discussion among Mars scientists. This image is located near 12.5oN, 177.5oW. The image covers an area approximately 3 km (1.9 mi) across and is illuminated by sunlight from the left/lower left.

Outer Dregs

NASA Technical Reports Server (NTRS)

2006-01-01

15 May 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows the very edge of the south polar residual cap of Mars. The bright areas, which appear somewhat like pieces of sliced Swiss cheese, are composed mainly of frozen carbon dioxide. The scarps around the edges of the carbon dioxide mesas have been retreating at a rate of roughly 3 meters (3 yards) per martian year; in this case, exposing a darker surface that lies below.

Location near: 85.4oS, 88.6oW Image width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Summer

Cracked Mars

NASA Technical Reports Server (NTRS)

2006-01-01

25 June 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows v-shaped troughs in the Hephaestus Fossae region of Mars. Light-toned, windblown ripples reside in the very lowest parts of the troughs, as well as on the cratered upland outside the troughs. Boulders and other types of debris, which were derived from the layered rock exposed near the top of the troughs, are seen resting on the trough floors and perched on the sloping trough walls.

Location near: 21.1oN, 236.7oW Image width: 3 km (1.9 mi) Illumination from: lower left Season: Northern Spring

Fretted Terrain Valleys

NASA Technical Reports Server (NTRS)

2004-01-01

30 October 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows shallow tributary valleys in the Ismenius Lacus fretted terrain region of northern Arabia Terra. These valleys exhibit a variety of typical fretted terrain valley wall and floor textures, including a lineated, pitted material somewhat reminiscent of the surface of a brain. Origins for these features are still being debated within the Mars science community; there are no clear analogs to these landforms on Earth. This image is located near 39.9oN, 332.1oW. The picture covers an area about 3 km (1.9 mi) wide. Sunlight illuminates the scene from the lower left.

Cut By Troughs

NASA Technical Reports Server (NTRS)

2005-01-01

1 September 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows an impact crater cut by troughs which formed after the crater formed. The crater and troughs have large windblown ripples on their floors. The ripples, troughs, craters, and other surfaces in this scene have all been mantled by dust. Dark streaks on slopes indicate areas where avalanches of dry dust have occurred. These features are located on Sacra Mena, a large mesa in the Kasei Valles region.

Location near: 25.4oN, 66.8oW Image width: width: 3 km (1.9 mi) Illumination from: lower left Season: Northern Autumn

Mars Global Surveyor Approach Image

NASA Technical Reports Server (NTRS)

1997-01-01

This image is the first view of Mars taken by the Mars Global Surveyor Orbiter Camera (MOC). It was acquired the afternoon of July 2, 1997 when the MGS spacecraft was 17.2 million kilometers (10.7 million miles) and 72 days from encounter. At this distance, the MOC's resolution is about 64 km per picture element, and the 6800 km (4200 mile) diameter planet is 105 pixels across. The observation was designed to show the Mars Pathfinder landing site at 19.4 N, 33.1 W approximately 48 hours prior to landing. The image shows the north polar cap of Mars at the top of the image, the dark feature Acidalia Planitia in the center with the brighter Chryse plain immediately beneath it, and the highland areas along the Martian equator including the canyons of the Valles Marineris (which are bright in this image owing to atmospheric dust). The dark features Terra Meridiani and Terra Sabaea can be seen at the 4 o`clock position, and the south polar hood (atmospheric fog and hazes) can be seen at the bottom of the image. Launched on November 7, 1996, Mars Global Surveyor will enter Mars orbit on Thursday, September 11 shortly after 6:00 PM PDT. After Mars Orbit Insertion, the spacecraft will use atmospheric drag to reduce the size of its orbit, achieving a circular orbit only 400 km (248 mi) above the surface in early March 1998, when mapping operations will begin.

The Mars Global Surveyor is operated by the Mars Surveyor Operations Project managed for NASA by the Jet Propulsion Laboratory, Pasadena CA. The Mars Orbiter Camera is a duplicate of one of the six instruments originally developed for the Mars Observer mission. It was built and is operated under contract to JPL by an industry/university team led by Malin Space Science Systems, San Diego, CA.

Layers within the Valles Marineris: Clues to the Ancient Crust of Mars - High Resolution Image

NASA Technical Reports Server (NTRS)

1998-01-01

This high resolution picture of the Martian surface was obtained in the early evening of January 1, 1998 by the Mars Orbiter Camera (MOC), shortly after the Mars Global Surveyor spacecraft began it's 80th orbit. Seen in this view are a plateau and surrounding steep slopes within the Valles Marineris, the large system of canyons that stretches 4000 km (2500 mi) along the equator of Mars. The image covers a tiny fraction of the canyons at very high resolution: it extends only 9.8 km by 17.3 km (6.1 mi by 10.7 mi) but captures features as small as 6 m (20 ft) across. The highest terrain in the image is the relatively smooth plateau near the center. Slopes descend to the north and south (upper and lower part of image, respectively) in broad, debris-filled gullies with intervening rocky spurs. Multiple rock layers, varying from a few to a few tens of meters thick, are visible in the steep slopes on the spurs and gullies. Layered rocks on Earth form from sedimentary processes (such as those that formed the layered rocks now seen in Arizona's Grand Canyon) and volcanic processes (such as layering seen in the Waimea Canyon on the island of Kauai). Both origins are possible for the Martian layered rocks seen in this image. In either case, the total thickness of the layered rocks seen in this image implies a complex and extremely active early history for geologic processes on Mars.

Malin Space Science Systems (MSSS) and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

The effects of thermal gradients on the Mars Observer Camera primary mirror

NASA Technical Reports Server (NTRS)

Applewhite, Roger W.; Telkamp, Arthur R.

1992-01-01

The paper discusses the effect of thermal gradients on the optical performance of the primary mirror of Mars Observer Camera (MOC), which will be launched on the Mars Observer spacecraft in September 1992. It was found that mild temperature gradients can have a large effect on the mirror surface figure, even for relatively low coefficient-of-thermal-expansion materials. However, in the case of the MOC primary mirror, it was found that the radius of curvature (ROC) of the reflective surface of the mirror changed in a nearly linear fashion with the radial temperature gradient, with little additional aberration. A solid-state ROC controller using the thermal gradient effect was implemented and verified.

Evidence for Recent Liquid Water on Mars: Seepage Sites in 'Aerobraking Crater' Revisited

NASA Technical Reports Server (NTRS)

2000-01-01

(A) [figure removed for brevity, see original site] (B) [figure removed for brevity, see original site] (C) (D) You will need 3D glasses to view this anaglyph

The first clue that there might be places on Mars where liquid groundwater seeps out onto the surface came from a picture taken by the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) during the pre-mapping Orbit Insertion Phase of the mission. The picture, shown in (A)above, was taken at the end of December 1997 while the spacecraft was still in the midst of aerobraking maneuvers to put it into the circular orbit needed for the Mapping Phase of the project. The Aerobraking 1 image, AB1-07707, showed dark, v-shaped scars on the western wall of a 50 kilometer-(31 mile)-diameter impact crater in southern Noachis Terra at 65oS, 15oW (see B, above, for context). The v-shaped features taper downslope to form narrow, somewhat curved channels. The relationship seen here was interpreted by MOC scientists to be similar to seepage landforms on Earth that form where springs emerge on a slope and water runs downhill.

Once MGS achieved its Mapping Orbit in March 1999, the MOC was in a better position to take pictures of 10 times higher resolution than the Aerobraking AB1-07707 image. The opportunity to take a new picture of the proposed 'seepage' sites on the wall of the crater in southern Noachis finally arose in January 2000. The result is MOC image M11-00530, shown above in (top) and (C). This new close-up shows that the darkly-shaped scars host many small channels of only a few meters (yards) across. These small channels run downslope and coalesce at the apex (or point) of each 'v'. Amid the small channels are many large boulders, some of them the size of houses, that have eroded out of the crater wall. A 3-D view created using the AB1 and M11 images is shown in (D). The stereo picture (red-blue '3D' glasses required) emphasizes the presence of small channels and valleys, and shows that these valleys start almost at the very top of the v-shaped dark areas.

The context picture in (B) is a mosaic of Viking 2 orbiter images 497B47 and 497B48 acquired December 28, 1977. The Aerobraking MGS MOC image, AB1-07707, is shown overlain on the Viking context image; it was taken 20 years later on December 29, 1997. The smaller white box in the context picture shows the location of MOC Mapping Phase image M11-00530, roughly 2 years later on January 4, 2000. North is 'up' in pictures (A) and (B), and to the lower right in (top), (C), and (D). Sunlight illuminates (A) from the upper left, (B) from the upper right, and (top) and (C) from the upper right. The top image in (top) is the aerobraking image, AB1-07707, with a white box indicating the location of the lower image, M11-00530, and the stereo pair in (D). The white box on the left in (C) shows the location of the close-up on the right in (C).

Detailed View of Cliff-face in the North Polar Layered Deposits

NASA Technical Reports Server (NTRS)

1998-01-01

On Earth, geologists use layers of rock to 'read' the history of our planet. Where rocks were initially formed as layers of sediment, the historic record of Earth is deciphered by knowing that older layers are found beneath the younger layers. Scientists investigating changes in Earth's climate over the past few million years also use this principle to examine cores of ice from Greenland and Antarctica. Layered rock and layered polar deposits on Mars may also preserve a comparable record of that planet's geologic and environmental history.

The martian north and south polar regions are covered by large areas of layered deposits. Since their discovery in the early 1970's, these polar layered deposits have been cited as the best evidence that the martian climate experiences cyclic changes over time. It was proposed that detailed investigation of the polar layers (e.g., by landers and/or human beings) would reveal a climate record of Mars in much the same way that ice cores from Antarctica are used to study past climates on Earth. On January 3, 1999, NASA's Mars Polar Lander and Deep Space 2 Penetrators will launch on a journey to study the upper layers of these deposits in the martian southern hemisphere.

Meanwhile, investigation of the north polar layered deposits has advanced significantly this year with the acquisition of MGS data. The Mars Orbiter Laser Altimeter acquired new topographic profiles over the north polar deposits in June and early July, 1998, and dozens of new high resolution images were taken by the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) from mid-July to mid-September, 1998. When it was proposed to NASA in 1985, one of the original objectives of MOC was to determine whether the polar layered deposits--then thought to consist of 10 to 100 layers each between 10 and 100 meters (33 to 330 feet) thick--have more and thinner layers in them. The layers were proposed to have formed by slow accumulation of dust and ice--perhaps only 100 micrometers (0.004 inches) per year. A layer 10 meters (33 feet) thick would take 100,000 years to accumulate, roughly equal to the timescale of climate changes predicted by computer models.

The image shown here (right image) was taken at 11:52 p.m. PDT on July 30, 1998, near the start of the 461st orbit of Mars Global Surveyor. The picture shows a slope along the edge of the permanent north polar cap of Mars that has dozens of layers exposed in it. The image shows many more layers than were visible to the Viking Orbiters in the 1970s (left images). The layers appear to have different thicknesses (some thinner than 10 meters (33 feet)) and different physical expressions. Some of the layers form steeper slopes than others, suggesting that they are more resistant to erosion. The more resistant layers might indicate that a cement (possibly ice) is present, making those layers stronger. All of the layers appear to have a rough texture that might be the result of erosion and/or redistribution of sediment and polar ice on the slope surface.

The presence of many more layers than were seen by Viking is an important and encouraging clue that suggests that future investigation of polar layered deposits by landers and, perhaps some day, by human explorers, will eventually lead to a better understanding of the of the polar regions and the climate history recorded there. Our view of these deposits will be much improved--starting in late March 1999--when the Mapping Phase of the MGS mission begins, and MOC will be able to obtain images with resolutions of 1.5 meters (5 feet) per pixel.

[The Viking Images (left)]: Regional and local context of MOC image 46103. The small figure in the upper right corner is a map of the north polar region, centered on the pole with 0o longitude located in the lower middle of the frame. A small black box within the polar map indicates the location of the Viking Orbiter 2 image used here for local context. The Viking image, 560b60, was taken in March 1978, toward the end of Northern Spring. The thin strip superposed on the Viking image is MOC image 46103, reduced in size to mark its placement relative to the Viking context image. The black box on the MOC image shows the location of the subframe highlighted here (right image). Illumination is from the left in the Viking image. The 10 kilometer scale bar also represents approximately 6.2 miles.

Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

Small Tharsis Volcano

NASA Technical Reports Server (NTRS)

2004-01-01

30 August 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a small volcano located southwest of the giant volcano, Pavonis Mons, near 2.5oS, 109.4oW. Lava flows can be seen to have emanated from the summit region, which today is an irregularly-shaped collapse pit, or caldera. A blanket of dust mantles this volcano. Dust covers most martian volcanoes, none of which are young or active today. This picture covers an area about 3 km (1.9 mi) across; sunlight illuminates the scene from the left.

Geographic Information Systems and Martian Data: Compatibility and Analysis

NASA Technical Reports Server (NTRS)

Jones, Jennifer L.

2005-01-01

Planning future landed Mars missions depends on accurate, informed data. This research has created and used spatially referenced instrument data from NASA missions such as the Thermal Emission Imaging System (THEMIS) on the Mars Odyssey Orbiter and the Mars Orbital Camera (MOC) on the Mars Global Surveyor (MGS) Orbiter. Creating spatially referenced data enables its use in Geographic Information Systems (GIS) such as ArcGIS. It has then been possible to integrate this spatially referenced data with global base maps and build and populate location based databases that are easy to access.

Mars at Ls 121o

NASA Technical Reports Server (NTRS)

2006-01-01

1 October 2006 These images capture what Mars typically looks like in mid-afternoon at L _s 121o. In other words, with the exception of occasional differences in weather and polar frost patterns, this is what the red planet looks like this month (October 2006).

Six views are shown, including the two polar regions. These are composites of 24-26 Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) daily global mapping images acquired at red and blue wavelengths. The 'hole' over the south pole is an area where no images were obtained, because this polar region is enveloped in wintertime darkness.

Presently, it is summer in the northern hemisphere and winter in the southern hemisphere. L_s, solar longitude, a measure of the time of year on Mars. Mars travels 360o around the Sun in 1 Mars year. The year begins at L_s 0o, the start of northern spring and southern autumn. Northern summer/southern winter begins at L_s 90o, northern autumn/southern spring start at L_s 180o, and northern winter/southern summer begin at L_s 270o.

L_s 121o occurs in the middle of this month (October 2006). The pictures show how Mars appeared to the MOC wide angle cameras at a previous L_s 121o in February 2001. The six views are centered on the Tharsis region (upper left), Acidalia and Mare Eyrthraeum (upper right), Syrtis Major and Hellas (middle left), Elysium and Mare Cimmeria (middle right), the north pole (lower left), and the south pole (lower right).

Frost in Charitum Montes

NASA Technical Reports Server (NTRS)

2003-01-01

MGS MOC Release No. MOC2-387, 10 June 2003

This is a Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) wide angle view of the Charitum Montes, south of Argyre Planitia, in early June 2003. The seasonal south polar frost cap, composed of carbon dioxide, has been retreating southward through this area since spring began a month ago. The bright features toward the bottom of this picture are surfaces covered by frost. The picture is located near 57oS, 43oW. North is at the top, south is at the bottom. Sunlight illuminates the scene from the upper left. The area shown is about 217 km (135 miles) wide.

Dunes in Twilight

NASA Technical Reports Server (NTRS)

2004-01-01

17 January 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows frost-covered north polar dunes in early January 2004. When this picture was taken, the dunes were in twilight, just before the late winter dawn that would come a few days later. These dunes spent many of the last several months in complete darkness. In this image, they are illuminated only by sunlight that has been scattered over the horizon by the martian atmosphere. These dunes are located near 77.0oN, 246.2oW. The image covers an area 3 km (1.9 mi) wide and has been expanded by 200% from its original 12 meters (39 ft.) per pixel scale. While the sun had not yet risen when the image was obtained, illumination is mostly from the lower left.

The HRSC on Mars Express: Mert Davies' Involvement in a Novel Planetary Cartography Experiment

NASA Astrophysics Data System (ADS)

Oberst, J.; Waehlisch, M.; Giese, B.; Scholten, F.; Hoffmann, H.; Jaumann, R.; Neukum, G.

2002-12-01

Mert Davies was a team member of the HRSC (High Resolution Stereo Camera) imaging experiment (PI: Gerhard Neukum) on ESA's Mars Express mission. This pushbroom camera is equipped with 9 forward- and backward-looking CCD lines, 5184 samples each, mounted in parallel, perpendicular to the spacecraft velocity vector. Flight image data with resolutions of up to 10m/pix (from an altitude of 250 km) will be acquired line by line as the spacecraft moves. This acquisition strategy will result in 9 separate almost completely overlapping image strips, each of them having more than 27,000 image lines, typically. [HRSC is also equipped with a superresolution channel for imaging of selected targets at up to 2.3 m/pixel]. The combined operation of the nadir and off-nadir CCD lines (+18.9°, 0°, -18.9°) gives HRSC a triple-stereo capability for precision mapping of surface topography and for modelling of spacecraft orbit- and camera pointing errors. The goals of the camera are to obtain accurate control point networks, Digital Elevation Models (DEMs) in Mars-fixed coordinates, and color orthoimages at global (100% of the surface will be covered with resolutions better than 30m/pixel) and local scales. With his long experience in all aspects of planetary geodesy and cartography, Mert Davies was involved in the preparations of this novel Mars imaging experiment which included: (a) development of a ground data system for the analysis of triple-stereo images, (b) camera testing during airborne imaging campaigns, (c) re-analysis of the Mars control point network, and generation of global topographic orthoimage maps on the basis of MOC images and MOLA data, (d) definition of the quadrangle scheme for a new topographic image map series 1:200K, (e) simulation of synthetic HRSC imaging sequences and their photogrammetric analysis. Mars Express is scheduled for launch in May of 2003. We miss Mert very much!

Rotated Perspective View of Nirgal Vallis

NASA Technical Reports Server (NTRS)

1997-01-01

This is the full-resolution, rotated perspective image of Nirgal Vallis, a subset of PIA00942. Nirgal Vallis is one of a number of canyons called valley networks or runoff channels. Much of the debate concerning the origin of these valleys centers on whether they were formed by water flowing across the surface, or by collapse and upslope erosion associated with groundwater processes. At the resolution of this image, it is just barely possible to discern an interwoven pattern of lines on the highland surrounding the valley, but it is not possible to tell whether this is a pattern of surficial debris (sand or dust), as might be expected with the amount of crater burial seen, or a pattern of drainage channels. With 4X better resolution from its mapping orbit, MOC should easily be able to tell the difference between these two possibilities.

Launched on November 7, 1996, Mars Global Surveyor entered Mars orbit on Thursday, September 11, 1997. The spacecraft has been using atmospheric drag to reduce the size of its orbit for the past three weeks, and will achieve a circular orbit only 400 km (248 mi) above the surface early next year. Mapping operations begin in March 1998. At that time, MOC narrow angle images will be 5-10 times higher resolution than these pictures.

Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

Warrego Valles

NASA Technical Reports Server (NTRS)

2004-01-01

3 October 2004 When viewed at 100 to 300 meters per pixel in old Mariner 9 and Viking orbiter images, Warrego Valles appears to be a grouping of intricately-carved networks of branching valleys. This region has often been used as the type example of martian valley networks, and key evidence that Mars may have once been warmer, wetter, and perhaps had precipitation in the form of rain or snow. However, when viewed at very high resolution (1.5 to 4.5 meters per pixel) with the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC), the Warrego valleys break down into a series of vaguely continuous (in other words, not necessarily connected to each other) troughs that have been covered and partially filled by a material that has eroded to form a very rough-textured surface. None of the original valley floor or wall features are visible because of this rough-textured mantle, and thus very little can be said regarding whether the valleys represent the results of persistent flow and precipitation runoff. Despite the MOC observations and the relatively unique nature of these valleys relative to other valley networks on Mars, the Warrego Valles continue to be used by many as an example of typical martian valley networks. The picture shown here is a mosaic of three MOC narrow angle images obtained in 1999 and 2004: M07-02071, R15-00492, and R15-02626. The dark bar near the bottom center is the location of a data drop, lost during transmission. The 1 km scale bar is approximately equal to 0.62 miles. Sunlight illuminates the images from the upper left, north is up, and the scene is located near 42.4oS, 93.5oW.

MGS Approach Image - 352.2o W longitude

NASA Technical Reports Server (NTRS)

1997-01-01

The bright area at the center of this view of Mars taken by the MGS/MOC is called Arabia. It contains some of the brightest ground on Mars, thought to be especially deep or fresh dust deposits. Syrtis Major, the dark feature curving north-south near the center edge of the planet, is devoid of large amounts of dust, probably because sand moves for frequently there and kicks up the dust into the martian air where it can be transported away. The dark 'splotches' near the middle top of the image are small sand dune fields trapped in the depressions of the Protonilus and Nilosyrtis 'fretted terrain' (a zone of valleys formed by tectonic fracturing and subsequent erosion). In the lower portion of the image is Terra Sabaea, a heavily cratered area near regions where major dust storms occur. The light, semicircular indentation is the 480 km diameter crater Schiaparelli.

Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

Schiaparelli Sedimentary Rocks

NASA Technical Reports Server (NTRS)

2003-01-01

MGS MOC Release No. MOC2-403, 26 June 2003

Some of the most important high resolution imaging results of the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) experiment center on discoveries about the presence and nature of the sedimentary rock record on Mars. This old meteor impact crater in northwestern Schiaparelli Basin exhibits a spectacular view of layered, sedimentary rock. The 2.3 kilometer (1.4 miles) wide crater may have once been completely filled with sediment; the material was later eroded to its present form. Dozens of layers of similar thickness and physical properties are now expressed in a wedding cake-like stack in the middle of the crater. Sunlight illuminating the scene from the left shows that the circle, or mesa top, at the middle of the crater stands higher than the other stair-stepped layers. The uniform physical properties and bedding of these layers might indicate that they were originally deposited in a lake (it is possible that the crater was at the bottom of a much larger lake, filling Schiaparelli Basin); alternatively, the layers were deposited by settling out of the atmosphere in a dry environment. This picture was acquired on June 3, 2003, and is located near 0.9oS, 346.2oW.

Marte Valles Crater 'Island'

NASA Technical Reports Server (NTRS)

2004-01-01

10 April 2004 Marte Valles is an outflow channel system that straddles 180oW longitude between the region south of Cerberus and far northwestern Amazonis. The floor of the Marte valleys have enigmatic platy flow features that some argue are formed by lava, others suggest they are remnants of mud flows. This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows an island created in the middle of the main Marte Valles channel as fluid---whether lava or mud---flowed past two older meteor impact craters. The craters are located near 21.5oN, 175.3oW. The image covers an area about 3 km (1.9 mi) across. Sunlight illuminates the scene from the lower left.

High Latitude Polygons

NASA Technical Reports Server (NTRS)

2004-01-01

21 September 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows polygon patterned ground in the south polar region near 82.0oS, 90.8oW. Polygons are fairly common at high latitudes in both martian hemispheres, but they do not occur everywhere. On Earth, features such as these would be good indicators of the presence and freeze-thaw cycles of ground ice. On Mars, the same might (emphasis on might) also be true. This image covers an area approximately 3 km (1.9 mi) across and is illuminated by sunlight from the upper left. Seasonal frost enhances the contrast in the scene; the darkest areas have advanced the farthest in the springtime defrosting process.

Frosty Polygons

NASA Technical Reports Server (NTRS)

2004-01-01

16 January 2004 Looking somewhat like a roadmap, this 3 km (1.9 mi) wide view of a cratered plain in the martian south polar region shows a plethora of cracks that form polygonal patterns. This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image is located near 78.9oS, 357.3oW. Polygons such as these, where they are found on Earth, would be indicators of the presence of subsurface ice. Whether the same is true for Mars is uncertain. What is certain is that modern, seasonal frost on the surface enhances the appearance of the polygons as the frost persists longer in the cracks than on adjacent plains. This southern springtime image is illuminated by sunlight from the upper left.

Frozen Frozen CO2

NASA Technical Reports Server (NTRS)

2005-01-01

2 October 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a view of frozen carbon dioxide in the south polar residual cap of Mars. Much of the south polar residual cap exhibits terrain that resembles stacks of sliced Swiss cheese, but this portion of the cap lacks the typical, circular depressions that characterize much of the region. Carbon dioxide on Mars freezes at a temperature of around 148 Kelvins, which is -125oC or about -193oF.

Location near: 87.2oS, 28.4oW Image width: width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Spring

Age Relationship

NASA Technical Reports Server (NTRS)

2006-01-01

12 June 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a group of impact craters in Aonia Planum, Mars. Remarkably, two of the craters are approximately equal in size, however, they clearly differ in age. The left (west) crater has a well-defined rim and its ejecta blanket overlies part of the less pronounced crater to its immediate east. The one with the ejecta blanket is younger. Other circular depressions in this bouldery scene are also old, eroded impact craters.

Location near: 59.5oS, 78.5oW Image width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Autumn

Intersection

NASA Technical Reports Server (NTRS)

2006-01-01

9 June 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a small portion of a dust-covered plain directly north of Labyrinthus Noctis which is cut by three linear troughs. The two long troughs running diagonally from the lower left (southwest) to the upper right (northeast) are connected by a third, shorter trough. Boulders derived from erosion of layered rock in the trough walls are seen perched on the sloping sidewalls and resting on the trough floors among giant windblown ripples.

Location near: 0.2oN, 105.0oW Image width: 3 km (1.9 mi) Illumination from: upper left Season: Northern Spring

Collapse Pits

NASA Technical Reports Server (NTRS)

2005-01-01

24 April 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a large and several small pits formed by collapse along the trend of a fault system in the Uranius Fossae region of Mars. Running diagonal from middle-right toward lower left is a trough that intersects the pit. The trough is a typical graben formed by faulting as the upper crust of Mars split and pulled apart at this location. The opening of the graben also led to formation of the collapse pits.

Location near: 26.2oN, 88.7oW Image width: 3 km (1.9 mi) Illumination from: lower left Season: Northern Summer

Martian City Map

NASA Technical Reports Server (NTRS)

2004-01-01

30 May 2004 Seasonal frost can enhance the view from orbit of polar polygonal patterns on the surface of Mars. Sometimes these patterns look something like a city map, or the view from above a city lit-up at night. This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows an example from the south polar region near 80.7oS, 70.6oW. Polar polygons on Mars are generally believed, though not proven, to be the result of freeze/thaw cycles of ice occurring within the upper few meters (several yards) of the martian subsurface. The image shown here covers an area about 3 km (1.9 mi) across; sunlight illuminates the scene from the upper left.

Recent developments with the Mars Observer Camera graphite/epoxy structure

NASA Astrophysics Data System (ADS)

Telkamp, Arthur R.

1992-09-01

The Mars Observer Camera (MOC) is one of the instruments aboard the Mars Observer Spacecraft to be launched not later than September 1992, whose mission is to geologically and climatologically map the Martian surface and atmosphere over a period of one Martian year. This paper discusses the events in the development of MOC that took place in the past two years, with special attention given to the implementation of thermal blankets, shields, and thermal control paints to limit solar absorption while controlling stray light; vibration testing of Flight Unit No.1; and thermal expansion testing. Results are presented of thermal-vac testing Flight Unit No. 1. It was found that, although the temperature profiles were as predicted, the thermally-induced focus displacements were not.

Mars Global Surveyor Approach Image

NASA Image and Video Library

1997-07-04

This image is the first view of Mars taken by the Mars Global Surveyor Orbiter Camera (MOC). It was acquired the afternoon of July 2, 1997 when the MGS spacecraft was 17.2 million kilometers (10.7 million miles) and 72 days from encounter. At this distance, the MOC's resolution is about 64 km per picture element, and the 6800 km (4200 mile) diameter planet is 105 pixels across. The observation was designed to show the Mars Pathfinder landing site at 19.4 N, 33.1 W approximately 48 hours prior to landing. The image shows the north polar cap of Mars at the top of the image, the dark feature Acidalia Planitia in the center with the brighter Chryse plain immediately beneath it, and the highland areas along the Martian equator including the canyons of the Valles Marineris (which are bright in this image owing to atmospheric dust). The dark features Terra Meridiani and Terra Sabaea can be seen at the 4 o`clock position, and the south polar hood (atmospheric fog and hazes) can be seen at the bottom of the image. Launched on November 7, 1996, Mars Global Surveyor will enter Mars orbit on Thursday, September 11 shortly after 6:00 PM PDT. After Mars Orbit Insertion, the spacecraft will use atmospheric drag to reduce the size of its orbit, achieving a circular orbit only 400 km (248 mi) above the surface in early March 1998, when mapping operations will begin. http://photojournal.jpl.nasa.gov/catalog/PIA00606

Assessing Layered Materials in Gale Crater

NASA Technical Reports Server (NTRS)

Bridges, N. T.

2001-01-01

The recent analysis of high resolution Mars Orbiter Camera (MOC) images of layered outcrops in equatorial regions reinforces two important ideas, which will probably eventually become paradigms, about Mars: 1) It has had a long, complex geologic history marked by change, as manifested in the different layers observed, and 2) Standing bodies of water existed for substantial lengths of time, indicating clement conditions possibly conducive to life. Although observations of layering and evidence for lakes and oceans has been reported for years based on Mariner 9 and Viking data, the MOC data show that this layering is much more pervasive and complex than previously thought. These layered sites are ideal for studying the geologic, and possibly biologic, history of Mars. Here, a layered site within Gale Crater is advocated as a Mars Exploration Rover (MER) target. This is one of the few layered areas within closed depressions (e.g., other craters and Vallis Marineris) that meets the landing site constraints and is accessible to both MER A and B.

Mars at Ls 145o: Acidalia/Mare Erythraeum

NASA Technical Reports Server (NTRS)

2005-01-01

11 January 2004 This picture is a composite of Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) daily global images acquired at Ls 145o during a previous Mars year. This month, Mars looks similar, as Ls 145o occurs in mid-January 2005.

This picture shows the Acidalia/Mare Erythraeum face of Mars. Over the course of the month, additional faces of Mars as it appears at this time of year are being posted for MOC Picture of the Day.

Ls, solar longitude, is a measure of the time of year on Mars. Mars travels 360o around the Sun in 1 Mars year. The year begins at Ls 0o--the start of northern spring and southern summer. In January 2005, it is northern summer and southern winter. The seasons on Mars occur according to Ls, described in thefollowing table:

Ls Season 0 - 90 northern spring, southern autumn 90 - 180 northern summer, southern winter 180 - 270 northern autumn, southern spring 270 - 360 northern winter, southern summer

Mars at Ls 145o: Elysium/Mare Cimmerium

NASA Technical Reports Server (NTRS)

2005-01-01

This picture is a composite of Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) daily global images acquired at Ls 145 during a previous Mars year. This month, Mars looked similar, as Ls 145 occurred in mid-January 2005.

This picture shows the Elysium/Mare Cimmerium face of Mars. Over the course of the month, additional faces of Mars as it appears at this time of year were posted for MOC Picture of the Day.

Ls, solar longitude, is a measure of the time of year on Mars. Mars travels 360 around the Sun in 1 Mars year. The year begins at Ls 0 -- the start of northern spring and southern summer. In January 2005, it is northern summer and southern winter. The seasons on Mars occur according to Ls, described in the following table:

Ls Season 0 - 90 northern spring, southern autumn 90 - 180 northern summer, southern winter 180 - 270 northern autumn, southern spring 270 - 360 northern winter, southern summer

Surface albedo observations at Gusev Crater and Meridiani Planum, Mars

USGS Publications Warehouse

Bell, J.F.; Rice, M.S.; Johnson, J. R.; Hare, T.M.

2008-01-01

During the Mars Exploration Rover mission, the Pancam instrument has periodically acquired large-scale panoramic images with its broadband (739??338 nm) filter in order to estimate the Lambert bolometric albedo of the surface along each rover's traverse. In this work we present the full suite of such estimated albedo values measured to date by the Spirit and Opportunity rovers along their traverses in Gusev Crater and Meridiani Planum, respectively. We include estimated bolometric albedo values of individual surface features (e.g., outcrops, dusty plains, aeolian bed forms, wheel tracks, light-toned soils, and crater walls) as well as overall surface averages of the 43 total panoramic albedo data sets acquired to date. We also present comparisons to estimated Lambert albedo values taken from the Mars Global Surveyor Mars Orbiter Camera (MOC) along the rovers' traverses, and to the large-scale bolometric albedos of the sites from the Viking Orbiter Infrared Thermal Mapper (IRTM) and Mars Global Surveyor/Thermal Emission Spectrometer (TES). The ranges of Pancam-derived albedos at Gusev Crater (0.14 to 0.25) and in Meridiani Planum. (0.10 to 0.18) are in good agreement with IRTM, TES, and MOC orbital measurements. These data sets will be a useful tool and benchmark for future investigations of albodo variations with time, including measurements from orbital instruments like the Context Camera and High Resolution Imaging Science Experiment on Mars Reconnaissance Orbiter. Long-term, accurate albedo measurements could also be important for future efforts in climate modeling as well as for studies of active surface processes. Copyright 2008 by the American Geophysical Union.

Surface albedo observations at Gusev Crater and Meridiani Planum, Mars

NASA Astrophysics Data System (ADS)

Bell, J. F.; Rice, M. S.; Johnson, J. R.; Hare, T. M.

2008-05-01

During the Mars Exploration Rover mission, the Pancam instrument has periodically acquired large-scale panoramic images with its broadband (739 +/- 338 nm) filter in order to estimate the Lambert bolometric albedo of the surface along each rover's traverse. In this work we present the full suite of such estimated albedo values measured to date by the Spirit and Opportunity rovers along their traverses in Gusev Crater and Meridiani Planum, respectively. We include estimated bolometric albedo values of individual surface features (e.g., outcrops, dusty plains, aeolian bed forms, wheel tracks, light-toned soils, and crater walls) as well as overall surface averages of the 43 total panoramic albedo data sets acquired to date. We also present comparisons to estimated Lambert albedo values taken from the Mars Global Surveyor Mars Orbiter Camera (MOC) along the rovers' traverses, and to the large-scale bolometric albedos of the sites from the Viking Orbiter Infrared Thermal Mapper (IRTM) and Mars Global Surveyor/Thermal Emission Spectrometer (TES). The ranges of Pancam-derived albedos at Gusev Crater (0.14 to 0.25) and in Meridiani Planum (0.10 to 0.18) are in good agreement with IRTM, TES, and MOC orbital measurements. These data sets will be a useful tool and benchmark for future investigations of albedo variations with time, including measurements from orbital instruments like the Context Camera and High Resolution Imaging Science Experiment on Mars Reconnaissance Orbiter. Long-term, accurate albedo measurements could also be important for future efforts in climate modeling as well as for studies of active surface processes.

Spectacular Layers Exposed in Becquerel Crater

NASA Technical Reports Server (NTRS)

2001-01-01

Toward the end of its Primary Mapping Mission, the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) acquired one of its most spectacular pictures of layered sedimentary rock exposed within the ancient crater Becquerel. Pictures such as this one from January 25, 2001, underscore the fact that you never know from one day to the next what the next MOC images will uncover. While the Primary Mission ends January 31, 2001, thousands of new pictures--revealing as-yet-unseen terrain on the red planet--may be obtained during the Extended Mission phase, scheduled to run through at least April 2002.

The picture shown here reveals hundreds of light-toned layers in the 167 kilometers (104 miles) wide basin named for 19th Century French physicist Antoine H. Becquerel (1852-1908). These layers are interpreted to be sedimentary rocks deposited in the crater at some time in the distant past. They have since been eroded and exposed, revealing faults, dark layers between the bright layers, and a long geologic history (of unknown duration) recorded in these materials. Sets of parallel faults can be seen cutting across the layers in the left third of the image. Sunlight illuminates this scene from the top/upper right.

Mars Orbiter Camera Views the 'Face on Mars' - Calibrated, contrast enhanced, filtered,

NASA Technical Reports Server (NTRS)

1998-01-01

Shortly after midnight Sunday morning (5 April 1998 12:39 AM PST), the Mars Orbiter Camera (MOC) on the Mars Global Surveyor (MGS) spacecraft successfully acquired a high resolution image of the 'Face on Mars' feature in the Cydonia region. The image was transmitted to Earth on Sunday, and retrieved from the mission computer data base Monday morning (6 April 1998). The image was processed at the Malin Space Science Systems (MSSS) facility 9:15 AM and the raw image immediately transferred to the Jet Propulsion Laboratory (JPL) for release to the Internet. The images shown here were subsequently processed at MSSS.

The picture was acquired 375 seconds after the spacecraft's 220th close approach to Mars. At that time, the 'Face', located at approximately 40.8o N, 9.6o W, was 275 miles (444 km) from the spacecraft. The 'morning' sun was 25o above the horizon. The picture has a resolution of 14.1 feet (4.3 meters) per pixel, making it ten times higher resolution than the best previous image of the feature, which was taken by the Viking Mission in the mid-1970's. The full image covers an area 2.7 miles (4.4 km) wide and 25.7 miles (41.5 km) long. Processing Image processing has been applied to the images in order to improve the visibility of features. This processing included the following steps:

The image was processed to remove the sensitivity differences between adjacent picture elements (calibrated). This removes the vertical streaking.

The contrast and brightness of the image was adjusted, and 'filters' were applied to enhance detail at several scales.

The image was then geometrically warped to meet the computed position information for a mercator-type map. This corrected for the left-right flip, and the non-vertical viewing angle (about 45o from vertical), but also introduced some vertical 'elongation' of the image for the same reason Greenland looks larger than Africa on a mercator map of the Earth.

A section of the image, containing the 'Face' and a couple of nearly impact craters and hills, was 'cut' out of the full image and reproduced separately.

See PIA01440-1442 for additional processing steps. Also see PIA01236 for the raw image.

Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

Mars Orbiter Camera Views the 'Face on Mars' - Calibrated, contrast enhanced, filtered

NASA Technical Reports Server (NTRS)

1998-01-01

Shortly after midnight Sunday morning (5 April 1998 12:39 AM PST), the Mars Orbiter Camera (MOC) on the Mars Global Surveyor (MGS) spacecraft successfully acquired a high resolution image of the 'Face on Mars' feature in the Cydonia region. The image was transmitted to Earth on Sunday, and retrieved from the mission computer data base Monday morning (6 April 1998). The image was processed at the Malin Space Science Systems (MSSS) facility 9:15 AM and the raw image immediately transferred to the Jet Propulsion Laboratory (JPL) for release to the Internet. The images shown here were subsequently processed at MSSS.

The picture was acquired 375 seconds after the spacecraft's 220th close approach to Mars. At that time, the 'Face', located at approximately 40.8o N, 9.6o W, was 275 miles (444 km) from the spacecraft. The 'morning' sun was 25o above the horizon. The picture has a resolution of 14.1 feet (4.3 meters) per pixel, making it ten times higher resolution than the best previous image of the feature, which was taken by the Viking Mission in the mid-1970's. The full image covers an area 2.7 miles (4.4 km) wide and 25.7 miles (41.5 km) long. Processing Image processing has been applied to the images in order to improve the visibility of features. This processing included the following steps:

The image was processed to remove the sensitivity differences between adjacent picture elements (calibrated). This removes the vertical streaking.

The contrast and brightness of the image was adjusted, and 'filters' were applied to enhance detail at several scales.

The image was then geometrically warped to meet the computed position information for a mercator-type map. This corrected for the left-right flip, and the non-vertical viewing angle (about 45o from vertical), but also introduced some vertical 'elongation' of the image for the same reason Greenland looks larger than Africa on a mercator map of the Earth.

A section of the image, containing the 'Face' and a couple of nearly impact craters and hills, was 'cut' out of the full image and reproduced separately.

See PIA01441-1442 for additional processing steps. Also see PIA01236 for the raw image.

Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

Streamlined Island

NASA Technical Reports Server (NTRS)

2003-01-01

MGS MOC Release No. MOC2-514, 15 October 2003

This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) picture shows a streamlined island in Marte Vallis, a large outflow channel system that crosses the 180oW meridian between the Elysium and Amazonis regions of Mars. The flow patterns on the floor of Marte Vallis might be the remains of lava flows or mud flows. Marte is the Spanish word for Mars. Most of the largest valleys on the red planet are named for 'Mars' in various languages. This island is located near 21.8oN, 175.3oW. The picture covers an area 3 km (1.9 mi) wide and is illuminated by sunlight from the lower left.

South Polar 'Poodle'

NASA Technical Reports Server (NTRS)

2003-01-01

MGS MOC Release No. MOC2-422, 15 July 2003

Have you ever stared up at the clouds in the sky and seen the shapes of animals, people, or objects? Sometimes when the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) team is looking at newly-returned pictures from Mars, the same thing happens. This is a picture of pits and scarps in the frozen south polar carbon dioxide ice cap. Sunlight illuminates the scene from the upper right. At the bottom of the picture is a feature that resembles a long, thin poodle; its head faces to the left, the tail to the right. This picture is located near 86.9oS, 55.8oW.

MOC Views of Martian Solar Eclipses

NASA Technical Reports Server (NTRS)

1999-01-01

[figure removed for brevity, see original site]

The shadow of the martian moon, Phobos, has been captured in many recent wide angle camera views of the red planet obtained by the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC). Designed to monitor changes in weather and surface conditions, the wide angle cameras are also proving to be a good way to spot the frequent solar eclipses caused by the passage of Phobos between Mars and the Sun.

The first figure (above), shows wide angle red (left), blue (middle), and color composite (right) views of the shadow of Phobos (elliptical feature at center of each frame) as it was cast upon western Xanthe Terra on August 26, 1999, at about 2 p.m.local time on Mars. The image covers an area about 250 kilometers (155 miles) across and is illuminated from the left. The meandering Nanedi Valles is visible in the lower right corner of the scene. Note the dark spots on three crater floors--these appear dark in the red camera image (left) but are barely distinguished in the blue image (middle), while the shadow is dark in both images. The spots on the crater floors are probably small fields of dark sand dunes.

The second figure shows three samples of MOC's global image swaths, each in this case with a shadow of Phobos visible (arrow). The first scene (left) was taken on September 1, 1999, and shows the shadow of Phobos cast upon southern Elysium Planitia. The large crater with dark markings on its floor at the lower right corner is Herschel Basin. The second scene shows the shadow of Phobos cast upon northern Lunae Planum on September 8, 1999. Kasei Valles dominates the upper right and the deep chasms of Valles Marineris dominate the lower third of the September 8 image. The picture on the right shows the shadow of Phobos near the giant volcano, Olympus Mons (upper left), on September 25, 1999. Three other major volcanoes are visible from lower-center (Arsia Mons) and right-center (Pavonis Mons) to upper-middle-right (Ascraeus Mons).

Phobos and the smaller, more distant satellite, Deimos, were discovered in 1877 by Asaph Hall, an astronomer at the United States Naval Observatory in Washington, D.C. Hall had been hunting for martian satellites for some time, and was about to abandon the search when he was encouraged by his wife to continue. In honor of her role, the largest crater on Phobos was named Stickney, her maiden name. Phobos is a tiny, potato-shaped world that is only about 13 km by 11 km by 9 km (8 mi by 7 mi by 6 mi) in size.

In 1912 Edgar Rice Burroughs published a story entitled 'Under the Moons of Mars' (printed in book form in 1917 as A Princess of Mars) in which he referred to the 'hurtling moons of Barsoom' (Barsoom being the 'native' word for Mars in the fictional account). Burroughs was inspired by the fact that Phobos, having an orbital period of slightly less than 8 hours, would appear from Mars to rise in the west and set in the east only five and a half hours later. (Despite Burroughs' phrase, the outer moon, Deimos, can hardly be said to 'hurtle' -- it takes nearly 60 hours to cross the sky from east to west, rising on one day and not setting again for over two more.)

If you could stand on Mars and watch Phobos passing overhead, you would notice that this moon appears to be only about half the size of what Earth's Moon looks like when viewed from the ground. In addition, the Sun would seem to have shrunk to about 2/3 (or nearly 1/2) of its size as seen from Earth. Martian eclipses are therefore dark but not as spectacular as total solar eclipses on Earth can be. In compensation, the martian eclipses are thousands of times more common, occurring a few times a day somewhere on Mars whenever Phobos passes over the planet's sunlit side. Due to the changing geometry of the MGS orbit relative to that of Phobos, the shadow is actually seen in MOC global map images (like in the second figure above) about a dozen times a month.

The shadow of Phobos was seen during the Viking missions in the late 1970s, and in fact one day the shadow was observed to pass right over the Viking 1 lander. The surface of Phobos itself was first imaged by Mariner 9 in 1971, and global coverage was obtained by the Viking orbiters in 1976-80. Phobos was the target of the ill-fated Phobos 1 and Phobos 2 spacecraft, launched by the Soviet Union in 1988. Phobos 2 actually reached Mars in 1989 and obtained a few pictures of the satellite--it also captured the shadow of Phobos cast upon the martian surface using its thermal infrared imager, Termoskan. More recently, the MGS MOC observed the tiny moon four times in August and September 1998.

Complex Burial and Exhumation of South Polar Cap Pitted Terrain

NASA Technical Reports Server (NTRS)

2000-01-01

This image is illuminated by sunlight from the upper left. The two prominent bright stripes at the left/center of the image are covered with bright frost and thus create the illusion that they are sunlit from the lower left.

The large pits, troughs, and 'swiss cheese' of the south polar residual cap appear to have been formed in the upper 4 or 5 layers of the polar material. Each layer is approximately 2 meters (6.6 feet) thick. Some Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) images of this terrain show examples in which older pitted and eroded layers have been previously buried and are now being exhumed. The example shown here includes two narrow, diagonal slopes that trend from upper left toward lower right at the left/center portion of the frame. Along the bottoms of these slopes are revealed a layer that underlies them in which there are many more pits and troughs than in the upper layer. It is likely in this case that the lower layer formed its pits and troughs before it was covered by the upper layer. This observation suggests that the troughs, pits, and 'swiss cheese' features of the south polar cap are very old and form over long time scales.

The picture is located near 84.6oS, 45.1oW, and covers an area 3 km by 5 km (1.9 x 3.1 mi) at a resolution of about 3.8 meters (12 ft) per pixel. The image was taken during southern spring on August 29, 1999.

Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

Zephyria Channel System

NASA Technical Reports Server (NTRS)

2004-01-01

10 September 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a portion of an outflow channel system located in the Zephyria region, south of Cerberus, from which vast quantities of rough-surfaced material flowed. The channel system has no name and was not known prior to the MGS mission. The material that flowed through this system may have been extremely fluid lava, or it may have been water-rich mud. Research by members of the Mars science community regarding the nature and origin of flow materials in the Cerberus, Zephyria, and Marte Vallis regions of Mars is on-going. This image is located near 4.6oN, 204.1oW. The image covers an area approximately 3 km (1.9 mi) across and is illuminated by sunlight from the left/lower left.

Ripple Trap

NASA Technical Reports Server (NTRS)

2006-01-01

3 April 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows the margin of a lava flow on a cratered plain in the Athabasca Vallis region of Mars. Remarkably, the cratered plain in this scene is essentially free of bright, windblown ripples. Conversely, the lava flow apparently acted as a trap for windblown materials, illustrated by the presence of the light-toned, wave-like texture over much of the flow. That the lava flow surface trapped windblown sand and granules better than the cratered plain indicates that the flow surface has a rougher texture at a scale too small to resolve in this image.

Location near: 10.7oN, 204.5oW Image width: 3 km (1.9 mi) Illumination from: lower left Season: Northern Winter

Mesa in Aureum Chaos

NASA Technical Reports Server (NTRS)

2004-01-01

2 August 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a circular mesa and layered materials that are partially-exposed from beneath a thick, dark mantle in the Aureum Chaos region of Mars. The features are part of a much larger circular form (bigger than the image shown here) that marks the location of a crater that was filled with light-toned sedimentary rock, buried, and then later re-exposed when the upper crust of Mars broke apart in this region to form buttes and mesas of 'chaotic terrain.' The circular mesa in this image might also be the location of a formerly filled and buried crater. This image is located near 4.0oS, 26.9oW. It covers an area about 3 km (1.9 mi) across; sunlight illuminates the scene from the left/upper left.

Yard Sale

NASA Technical Reports Server (NTRS)

2006-01-01

17 July 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a bright plain west of Schiaparelli Crater, Mars, which is host to several features, some of them long-lived and others that are transient. The circular features scattered somewhat randomly throughout the scene are impact craters, all of which are in a variety of states of degradation. In the lower left (southwest) corner of the image, there is a small hill surrounded by ripples of windblown sediment, and near the center of the image, there is an active dust devil casting a shadow to the east as it makes its way across the plain.

Location near: 5.9oS, 348.2oW Image width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Autumn

Mars Says 'hi'!

NASA Technical Reports Server (NTRS)

2004-01-01

12 October 2004 Although one might argue that most of the 'i' is missing, and part of the 'h' has been eroded away, this Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows light-toned sedimentary rock outcrops in northern Sinus Meridiani that almost seem to spell out the word, 'hi'. This natural graffiti is all that remains of a suite of sedimentary rock that once covered the area shown here. The 400 meter scale bar is about 437 yards long. The features are located near 1.8oN, 357.2oW. Sunlight illuminates the scene from the upper left.

Large Ripples in Cerberus

NASA Technical Reports Server (NTRS)

2004-01-01

18 May 2004 Mars is a desert planet, upon which wind has a great influence on the expression of its surface materials. This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows large ripples (or small dunes) of windblown sediment among hills in the southeastern Cerberus region near 11.0oN, 199.5oW. Ripple orientations vary throughout the scene, indicating that dominant winds are influenced by the interplay of wind and local topographic features such as craters and hills. The picture covers an area about 3 km (1.9 mi) across and is illuminated by sunlight from the left/lower left.

Counting Craters on MOC Images: Production Functions and Other Complications

NASA Technical Reports Server (NTRS)

Plaut, J. J.

2001-01-01

New crater counts on MOC images and associated Viking Orbiter images are used to address the issue of the crater production function at Mars, and to infer aspects of resurfacing processes. Additional information is contained in the original extended abstract.

Evidence for Recent Liquid Water on Mars: 'Dry' Processes on One Slope; 'Wet' Processes on Another

NASA Technical Reports Server (NTRS)

2000-01-01

[figure removed for brevity, see original site] [figure removed for brevity, see original site]

How can martian gullies--thought to be caused in part by seepage and runoff of liquid water--be distinguished from the more typical, 'dry' slope erosion processes that also occur on Mars? For one thing, most--though not all--of the gully landforms occur on slopes that face away from the martian equator and toward the pole. For another, slopes that face toward the equator exhibit the same types of features as seen on nearly every other non-gullied slope on Mars.

The example shown here comes from northwestern Elysium Planitia in the martian northern hemisphere. The Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) high resolution view (A, left) shows a portion of a 10 kilometer-(6.2 mi)-diameter meteor impact crater at a resolution of about 9 meters (29.5 ft) per pixel. The crater is shown in the context image (B, middle). The north-facing (or, pole-ward) slope in the MOC view is shadowed because sunlight illuminates the scene from the lower left. In this shadowed area, a series of martian gullies--defined by their erosional alcoves, deep channels, and apron deposits--are seen. On the sunlit south-facing (or equator-ward) slope, a scene more typical of most martian impact craters is present--the upper slopes show layered bedrock, the lower slopes show light-toned streaks of dry debris that has slid down the slope forming talus deposits that are distinctly different from the lobe-like form of gully aprons. The picture in (C) has been rotated so that the two slopes--one with gullies (right) and one without (left)--can be compared.

The crater is located at 36.7oN, 252.3oW. The MOC image was acquired in November 1999 and covers an area 3 km (1.9 mi) wide by 14 km (8.7 mi) long; north is toward the upper right (in A) and it is illuminated by sunlight from the lower left. The Viking 1 orbiter context image (B) was obtained in 1978 and is illuminated from the left; north is up. The MOC image has been rotated in the Explanatory Figure (C) such that north is toward the upper left, illumination is from the lower right.

South Polar Hills

NASA Technical Reports Server (NTRS)

2006-01-01

28 January 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a summer scene from the south polar region of Mars. The circular feature in the northeast (upper right) corner of the image is an old meteor impact crater that has been partially filled and buried. The cone-shaped hill that occurs within the crater on its east (right) side is a remnant of material that once covered and completely buried the crater. Perhaps beneath the surfaces in the rest of the image there are other craters that have been filled and buried such that we cannot know, from an image, that they ever existed. The theme of filled, buried, and exhumed craters is one that repeats itself -- over and over again -- all over Mars.

Location near: 80.3oS, 286.1oW Image width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Summer

Marte Vallis Textures

NASA Technical Reports Server (NTRS)

2006-01-01

20 March 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows platy flow surfaces in the Marte Vallis region of Mars. The origin of the flows is not well-understood, but as some Mars scientists have suggested, the flows may be the product of low viscosity (very fluid), high temperature volcanic eruptions, or perhaps they are the remains of large-scale mud flows. In either case, the materials are solid and hold a record of small meteor impact craters, thus indicating that they are not composed of ice, as still others have speculated.

Location near: 6.7oN, 182.0oW Image width: 3 km (1.9 mi) Illumination from: lower left Season: Northern Winter

Transitions

NASA Technical Reports Server (NTRS)

2006-01-01

26 May 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a variety of textures observed on a dust-covered plain in the Marte Valles region of Mars. Textural variations across the scene include: areas that are littered with small impact craters, a channel-like feature that is dominated by mounds of a variety of sizes, small ripples and/or ridges, and relatively smooth, unremarkable terrain. The contact between the cratered plain and the area dominated by mounds marks one of the banks along the edge of one of the shallow valleys of the Marte Valles system.

Location near: 17.7oN, 175.0oW Image width: 3 km (1.9 mi) Illumination from: lower left Season: Northern Spring

High Latitude Polygons

NASA Technical Reports Server (NTRS)

2005-01-01

26 September 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows polygonal patterned ground on a south high-latitude plain. The outlines of the polygons, like the craters and hills in this region, are somewhat enhanced by the presence of bright frost left over from the previous winter. On Earth, polygons at high latitudes would usually be attributed to the seasonal freezing and thawing cycles of ground ice. The origin of similar polygons on Mars is less certain, but might also be an indicator of ground ice.

Location near: 75.3oS, 113.2oW Image width: width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Spring

The Pits

NASA Technical Reports Server (NTRS)

2006-01-01

8 March 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a portion of a pit chain on the lower, northern flank of the giant martian volcano, Arsia Mons. Pits such as these commonly form as a result of collapse of surface materials into a subsurface void, possibly along a fault or into an old lava tube. The layered material, exposed near the top of several of the pits, is shedding house-sized boulders which can be seen resting on the sloping sidewalls and floors of many of the pits.

Location near: 6.7oS, 120.1oW Image width: 3 km (1.9 mi) Illumination from: lower left Season: Southern Summer

Patches of Remnant Frost/Snow on Crater Rim in Northern Summer

NASA Technical Reports Server (NTRS)

1999-01-01

March 1999--it is summer in the martian northern hemisphere, yet patches of frost or snow persist in some areas of the northern plains. Winter ended eight months earlier, in July 1998. Recently, the Mars Orbiter Camera (MOC) passed over a relatively small impact crater located at latitude 68oN (on the Vastitas Borealis plain, north of Utopia Planitia) and took the picture seen at the left, above. The curved crater rims are visible in the upper and lower quarters of the image, and the crater floor is visible at the center right.

The picture on the right is a magnified view of the crater rim area outlined by a white box in the image on the left. The bright patches are snow or frost left over from the martian winter. These snowfields are so small that a human could walk across one of them in a matter of minutes--or perhaps sled down the small, sloping patch that is seen in a shadowed area near the lower left.

In winter, the entire scene shown here would be covered by frost. The long strip at the left covers an area 3 km (1.9 mi) wide by 26 km (16 mi) long. The expanded view on the right covers an area 2.9 km (1.8 mi) by 5.3 km (3.3 mi). Illumination is from the upper right.

Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

Clouds Near Mie Crater

NASA Image and Video Library

2003-12-13

Mie Crater, a large basin formed by asteroid or comet impact in Utopia Planitia, lies at the center of this Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) red wide angle image. The crater is approximately 104 km (65 mi) across. To the east and southeast (toward the lower right) of Mie, in this 5 December 2003 view, are clouds of dust and water ice kicked up by local dust storm activity. It is mid-winter in the northern hemisphere of Mars, a time when passing storms are common on the northern plains of the red planet. Sunlight illuminates this image from the lower left; Mie Crater is located at 48.5°N, 220.3°W. Viking 2 landed west/southwest of Mie Crater, off the left edge of this image, in September 1976. http://photojournal.jpl.nasa.gov/catalog/PIA04930

Small Crater Populations on Mars: Studies of MOC Images

NASA Technical Reports Server (NTRS)

Plaut, J. J.

2000-01-01

Populations of small martian craters can now be studied using MOC images. The smallest craters record aspects of the crater production and resurfacing history that could not be observed previously. Examples from a number of terrains are shown.

Why the New Gully Deposits are Not Dry Dust Slope Streaks

NASA Image and Video Library

2006-12-06

The light-toned deposits that formed in two gully sites on Mars during the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) mission in the 1999 to 2005 period are considered to be the result of sediment transport by a fluid with the physical properties of liquid water. The young, light-toned gully deposits were found in a crater in Terra Sirenum (see PIA09027 or MOC2-1618) and in a crater east of the Hellas basin in the Centauri Montes region (see PIA09028 or MOC2-1619). In their study of how the light-toned gully deposits may have formed, the MOC team considered their resemblance to light- and dark-toned slope streaks found elsewhere on Mars. Slope streaks are most commonly believed to have formed by downslope movement of extremely dry, very fine-grained dust, through processes thought by some to be analogous to terrestrial snow avalanche formation. http://photojournal.jpl.nasa.gov/catalog/PIA09030

Ripples and Dunes in the Syrtis Major Region of Mars, as Revealed in MOC Images

NASA Technical Reports Server (NTRS)

Zimbelman, J. R.; Wilson, S.

2002-01-01

Six categories of ripple-like aeolian bedforms have been identified in MOC images, and their physical attributes are compared to large ripples on Earth. Additional information is contained in the original extended abstract.

The Changing South Polar Cap of Mars: 1999-2005

NASA Technical Reports Server (NTRS)

2005-01-01

13 July 2005 The south polar residual cap of Mars is composed of layered, frozen carbon dioxide. In 1999, the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) showed that the carbon dioxide layers have been eroded to form a variety of circular pits, arcuate scarps, troughs, buttes, and mesas. In 2001, MOC images designed to provide repeated views of the areas imaged in 1999 -- with the hope of creating stereo (3-D) images, so that the height of scarps and depth of pits could be measured -- showed that the scarps had retreated, pits enlarged, and buttes and mesas shrank. Only carbon dioxide is volatile enough in the martian environment to have caused such dramatic changes -- the scarps were seen to retreat at an average rate of 3 meters (about 3 yards) per Mars year. Most of the scarp retreat occurs during the southern summer season; in some areas the scarps move as much as 8 meters, in others, only 1 meter per Mars year.

Three Mars years have now elapsed since MOC first surveyed the south polar cap in 1999. Over the past several months, MGS MOC has been re-imaging areas that were seen in 1999, 2001, and 2003, to develop a detailed look at how the landscape has been changing. This animated GIF provides an example of the dramatic changes that have occurred during the past three martian years. The first image, a sub-frame of M09-05244, was acquired on 21 November 1999. The second image, a sub-frame of S06-00973, was obtained on 11 May 2005. The animation shows the changes that have occurred between 1999 and 2005. Each summer, the cap has lost more carbon dioxide. This may mean that the carbon dioxide content of the martian atmosphere has been increasing, bit by very tiny little bit, each of the years that MGS has been orbiting the red planet. These observations also imply that there was once a time, in the not-too-distant past (because there are no impact craters on the polar cap), when the atmosphere was somewhat thinner and colder, to permit the layers of carbon dioxide to form in the first place. Just as Earth's environment is very different today than it was just 11,000 or so years ago, the martian environment has also been changing on a similar time scale.

Location near: 88.9oS, 25.7oW Image width: width: 0.6 km (0.4 mi) Illumination from: upper left Season: Southern Spring

'Sharks Teeth' -- Sand Dunes in Proctor Crater

NASA Technical Reports Server (NTRS)

2001-01-01

Sometimes, pictures received from Mars Global Surveyor's Mars Orbiter Camera (MOC) are 'just plain pretty.' This image, taken in early September 2000, shows a group of sand dunes at the edge of a much larger field of dark-toned dunes in Proctor Crater. Located at 47.9oS, 330.4oW, in the 170 km (106 mile) diameter crater named for 19th Century British astronomer Richard A. Proctor (1837-1888), the dunes shown here are created by winds blowing largely from the east/northeast. A plethora of smaller, brighter ripples covers the substrate between the dunes. Sunlight illuminates them from the upper left.

Location and Geologic Setting for the Three U.S. Mars Landers

NASA Technical Reports Server (NTRS)

Parker, T. J.; Kirk, R. L.

1999-01-01

Super resolution of the horizon at both Viking landing sites has revealed "new" features we use for triangulation, similar to the approach used during the Mars Pathfinder Mission. We propose alternative landing site locations for both landers for which we believe the confidence is very high. Super resolution of VL-1 images also reveals some of the drift material at the site to consist of gravel-size deposits. Since our proposed location for VL-2 is NOT on the Mie ejecta blanket, the blocky surface around the lander may represent the meter-scale texture of "smooth palins" in the region. The Viking Lander panchromatic images typically offer more repeat coverage than does the IMP on Mars Pathfinder, due to the longer duration of these landed missions. Sub-pixel offsets, necessary for super resolution to work, appear to be attributable to thermal effects on the lander and settling of the lander over time. Due to the greater repeat coverage (particularly in the near and mid-fields) and all-panchromatic images, the gain in resolution by super resolution processing is better for Viking than it is with most IMP image sequences. This enhances the study of textural details near the lander and enables the identification rock and surface textures at greater distances from the lander. Discernment of stereo in super resolution im-ages is possible to great distances from the lander, but is limited by the non-rotating baseline between the two cameras and the shorter height of the cameras above the ground compared to IMP. With super resolution, details of horizon features, such as blockiness and crater rim shapes, may be better correlated with Orbiter images. A number of horizon features - craters and ridges - were identified at VL-1 during the misison, and a few hils and subtle ridges were identified at VL-2. We have added a few "new" horizon features for triangulation at the VL-2 landing site in Utopia Planitia. These features were used for independent triangulation with features visible in Viking Orbiter and MGS MOC images, though the actual location of VL-1 lies in a data dropout in the MOC image of the area. Additional information is contained in the original extended abstract.

Outcrops In Aram Chaos

NASA Technical Reports Server (NTRS)

2004-01-01

16 October 2004 Aram Chaos is the name of an approximately 275 km (171 mi) diameter impact crater near Ares Vallis, roughly half way between the Mars Exploration Rover, Opportunity, site in Meridiani Planum and the easternmost troughs of the Valles Marineris. The Aram Chaos crater is partially filled with a thick accumulation of layered rock. Erosion has exposed light- and dark-toned rock materials in the basin. This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a small area exhibiting some of the rock outcrops in Aram Chaos. The light-toned rocks may be sedimentary in origin. This image is located near 4.0oN, 20.6oW, and covers an area about 3 km (1.9 mi) wide. Sunlight illuminates the scene from the upper left.

Carbon Dioxide Landscape

NASA Technical Reports Server (NTRS)

2005-01-01

23 July 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a view of some of the widely-varied terrain of the martian south polar residual cap. The landforms here are composed mainly of frozen carbon dioxide. Each year since MGS arrived in 1997, the scarps that bound each butte and mesa, or line the edges of each pit, in the south polar region, have changed a little bit as carbon dioxide is sublimed away. The scarps retreat at a rate of about 3 meters (3 yards) per martian year. Most of the change occurs during each southern summer.

Location near: 86.7oS, 9.8oW Image width: width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Spring

Defrosting Polar Dunes--'They Look Like Bushes!'

NASA Technical Reports Server (NTRS)

1999-01-01

'They look like bushes!' That's what almost everyone says when they see the dark features found in pictures taken of sand dunes in the polar regions as they are beginning to defrost after a long, cold winter. It is hard to escape the fact that, at first glance, these images acquired by the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) over both polar regions during the spring and summer seasons, do indeed resemble aerial photographs of sand dune fields on Earth--complete with vegetation growing on and around them! Of course, this is not what the features are, as we describe below and in related picture captions. Still, don't they look like vegetation to you? Shown here are two views of the same MGS MOC image. On the left is the full scene, on the right is an expanded view of a portion of the scene on the left. The bright, smooth surfaces that are dotted with occasional, nearly triangular dark spots are sand dunes covered by winter frost.

The MGS MOC has been used over the past several months (April-August 1999) to monitor dark spots as they form and evolve on polar dune surfaces. The dark spots typically appear first along the lower margins of a dune--similar to the position of bushes and tufts of grass that occur in and among some sand dunes on Earth.

Because the martian air pressure is very low--100 times lower than at Sea Level on Earth--ice on Mars does not melt and become liquid when it warms up. Instead, ice sublimes--that is, it changes directly from solid to gas, just as 'dry ice' does on Earth. As polar dunes emerge from the months-long winter night, and first become exposed to sunlight, the bright winter frost and snow begins to sublime. This process is not uniform everywhere on a dune, but begins in small spots and then over several months it spreads until the entire dune is spotted like a leopard.

The early stages of the defrosting process--as in the picture shown here--give the impression that something is 'growing' on the dunes. The sand underneath the frost is dark, just like basalt beach sand in Hawaii. Once it is exposed to sunlight, the dark sand probably absorbs sunlight and helps speed the defrosting of each sand dune.

This picture was taken by MGS MOC on July 21, 1999. The dunes are located in the south polar region and are expected to be completely defrosted by November or December 1999. North is approximately up, and sunlight illuminates the scene from the upper left. The 500 meter scale bar equals 547 yards; the 300 meter scale is also 328 yards.

Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

Mars Polar Lander Site Surface Details

NASA Technical Reports Server (NTRS)

1999-01-01

This picture is an enlargement of a portion of a MOC image taken in late July 1999, showing the onset of defrosting of the seasonal carbon dioxide frost cap (small, occasionally fan-shaped dark spots seen throughout this image). Two craters are seen in this image, a very rare occurrence on the south polar layered deposits. Shown for comparison at the same scale is a picture of Jack Murphy (now Qualcomm) Stadium in San Diego, California. Clearly visible in the inset is the baseball diamond and pitcher's mound; less clear but certainly visible are a number of automobiles (small light dots) in the parking lot west (to the left) of the stadium. The elevation of the sun in the Mars image is about 10o; the sunlight is coming from the bottom (north) in this image. The shadow of the rims of the craters can be used to determine their depths. The smaller crater in the bottom right corner is about 60 m (197 feet) across and 7 m (23 feet) deep; the large crater just below the inset is 175 m (574 feet) across and 17 m (56 feet) deep. Similar calculations for other features in the images indicate that much of the surface is smooth and flat. Relief is typically much less than 1-2 meters (3-7 feet) in height over areas of 10-15 meters across (33-49 feet).

Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

Mars Data analysis and visualization with Marsoweb

NASA Astrophysics Data System (ADS)

Gulick, V. G.; Deardorff, D. G.

2003-04-01

Marsoweb is a collaborative web environment that has been developed for the Mars research community to better visualize and analyze Mars orbiter data. Its goal is to enable online data discovery by providing an intuitive, interactive interface to data from the Mars Global Surveyor and other orbiters. Recently Marsoweb has served a prominent role as a resource center for the site selection process for the Mars Explorer Rover 2003 missions. In addition to hosting a repository of landing site memoranda and workshop talks, it includes a Java-based interface to a variety of data maps and images. This interface enables the display and numerical querying of data, and allows data profiles to be rendered from user-drawn cross-sections. High-resolution Mars Orbiter Camera (MOC) images (currently, over 100,000) can be graphically perused; browser-based image processing tools can be used on MOC images of potential landing sites. An automated VRML atlas allows users to construct "flyovers" of their own regions-of-interest in 3D. These capabilities enable Marsoweb to be used for general global data studies, in addition to those specific to landing site selection. As of December 2002, Marsoweb has been viewed by 88,000 distinct users with a total of 3.3 million hits (801,000 page requests in all) from NASA, USGS, academia, and the general public have accessed Marsoweb. The High Resolution Imaging Experiment team for the Mars 2005 Orbiter (HiRISE, PI Alfred McEwen) plans to cast a wide net to collect targeting suggestions. Members of the general public as well as the broad Mars science community will be able to submit suggestions of high resolution imaging targets. The web-based interface for target suggestion input (HiWeb) will be based upon Marsoweb (http://marsoweb.nas.nasa.gov).

Analysis of Spatial and Temporal Coverage of Multi-Instrument Optical Images for Change Detection Research on the Mars South Polar Residual Cap

NASA Astrophysics Data System (ADS)

Putri, Alfiah Rizky Diana; Sidiropoulos, Panagiotis; Muller, Jan-Peter; iMars Team

2016-10-01

Interest in Mars' surface started in 1965 with Mariner 4. Since then cameras on other fly-by satellites, such as the NASA Mariner 6 (1965), Mariner 7(1971), Mariner 9 (1972) and then orbiting satellites from Viking 1 and 2 (1975-1980), MGS MOC-NA and MOC-WA (1997-2006), Mars Odyssey THEMIS-VIS (2001-present), ESA Mars Express HRSC and SRC (2003-present), NASA MRO HiRISE and CTX (2006-present) and the latest ExoMars TGO CaSSIS launched in March 2016. Both poles of Mars are very fascinating because of their seasonal changes, such as Carbon Dioxide ice layers staying even in summer on South Polar Residual Cap (SPRC). On which features like so-called Swiss Cheese Terrain, spiders, polar dune flow and dust deposition under layers of ice have been identified. To detect changes between images, we need two or more co-registered images of the same area, and from different time periods, for seasonal features. We have studied the spatial and temporal coverage of images over SPRC. Using a single instrument, full SPRC spatial coverage is available for Viking, HRSC, and CTX images. Images from 25cm HiRISE and ≤10m MOC-NA however, are necessary to detect changes at sufficiently high resolution. The longest period for images from one instrument is 5 MY (for CTX and HiRISE, from MY 28-32). Combining multi-instrument images, we can lengthen the period to 10 MY (from MY 23-32, N.B. we are in MY 33 as present). We can compare the surface images over the 10 MY with the surface from MY 12 from Viking Orbiters. Using multi-instrument images we can increase the number of overlapping images over an area. Overlap information for a single instrument is important to obtain stereo-pairs to be used in DTM production. Overlap information from HRSC images and its DTMs can be used to map changes not only horizontally, but also vertically. We will demonstrate in this study the areas which can be most fruitfully employed for change detection research. The research leading to these results has received funding from the EU's FP7 Programme under iMars 607379. Partial support is also provided from the STFC Grant ST/K000977/1.. The first author is supported by the Indonesian Endowment Fund for Education, Ministry of Finance, Republic of Indonesia.

Wind vs. Dust Devil Streaks

NASA Technical Reports Server (NTRS)

2004-01-01

22 February 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image presents a fine illustration of the difference between streaks made by dust devils and streaks made by wind gusts. Dust devils are usually solitary, spinning vortices. They resemble a tornado, or the swirling motion of a familiar, Tasmanian cartoon character. Wind gusts, on the other hand, can cover a larger area and affect more terrain at the same time. The dark, straight, and parallel features resembling scrape marks near the right/center of this image are thought to have been formed by a singular gust of wind, whereas the more haphazard dark streaks that crisscross the scene were formed by dozens of individual dust devils, acting at different times. This southern summer image is located in Noachis Terra near 67.0oS, 316.2oW. Sunlight illuminates the scene from the upper left; the picture covers an area 3 km (1.9 mi) wide.

Summer South Polar Cap

NASA Technical Reports Server (NTRS)

2004-01-01

13 April 2004 The martian south polar residual ice cap is composed mainly of frozen carbon dioxide. Each summer, a little bit of this carbon dioxide sublimes away. Pits grow larger, and mesas get smaller, as this process continues from year to year. This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a view of a small portion of the south polar cap as it appeared in mid-summer in January 2004. The dark areas may be places where the frozen carbon dioxide contains impurities, such as dust, or places where sublimation of ice has roughened the surface so that it appears darker because of small shadows cast by irregularities in the roughened surface. The image is located near 86.9oS, 7.6oW. The image covers an area about 3 km (1.9 mi) across. Sunlight illuminates the scene from the upper left.

Characterization of MER Landing Sites Using MOC and MOLA

NASA Technical Reports Server (NTRS)

Anderson, F. S.; Parker, T. J.

2002-01-01

The MOC images for MER are compared with MOLA data to characterize and locate each image. MOLA profiles show that Hematite remains benign, Melas and Isidis are rougher, and Athabasca and Gusev have regions of significant small scale topography. Additional information is contained in the original extended abstract.

Recent Aqueous Environments in Impact Craters and the Astrobiological Exploration of Mars

NASA Technical Reports Server (NTRS)

Cabrol, N. A.; Wynn-Williams, D. D.; Crawford, D. A.; Grin, E. A.

2001-01-01

Three cases of recent aqueous environments are surveyed at Mars Orbiting Camera (MOC) high-resolution in the E-Gorgonum, Newton and Hale craters and their astrobiological implications assessed. Additional information is contained in the original extended abstract.

Martian 'Brain'

NASA Technical Reports Server (NTRS)

2004-01-01

5 May 2004 Most middle-latitude craters on Mars have strange landforms on their floors. Often, the floors have pitted and convoluted features that lack simple explanation. In this case, the central part of the crater floor shown in this 2004 Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image bears some resemblance to the folded nature of a brain. Or not. It depends upon the 'eye of the beholder,' perhaps. The light-toned 'ring' around the 'brain' feature is more easily explained--windblown ripples and dunes. The crater occurs near 33.1oS, 91.2oW, and is illuminated from the upper left. The picture covers an area about 3 km (1.9 mi) across.

Dunes with Frost

NASA Technical Reports Server (NTRS)

2004-01-01

31 May 2004 Springtime for the martian northern hemisphere brings defrosting spots and patterns to the north polar dune fields. This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows an example located near 76.7oN, 250.4oW. In summer, these dunes would be darker than their surroundings. However, while they are still covered by frost, they are not any darker than the substrate across which the sand is slowly traveling. Dune movement in this case is dominated by winds that blow from the southwest (lower left) toward the northeast (upper right). The picure covers an area about 3 km (1.9 mi) across and is illuminated by sunlight from the lower left.

South Polar Polygons

NASA Technical Reports Server (NTRS)

2004-01-01

4 March 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a spectacular suite of large and small polygons in the south polar region. On Earth, polygons such as these would be indicators of the presence of ground ice. Whether this is true for Mars remains to be determined, but it is interesting to note that these polygons do occur in a region identified by the Mars Odyssey Gamma Ray Spectrometer (GRS) team as a place with possible ground ice. The polygons are in an old impact crater located near 62.9oS, 281.4oW. This 1.5 meter (5 ft.) per pixel view covers an area 3 km (1.9 mi) wide and is illuminated by sunlight from the upper left. To see the smaller set of polygons, the reader must view the full-resolution image (click on picture, above).

Tharsis Limb Cloud

NASA Technical Reports Server (NTRS)

2005-01-01

[figure removed for brevity, see original site] Annotated image of Tharsis Limb Cloud

7 September 2005 This composite of red and blue Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) daily global images acquired on 6 July 2005 shows an isolated water ice cloud extending more than 30 kilometers (more than 18 miles) above the martian surface. Clouds such as this are common in late spring over the terrain located southwest of the Arsia Mons volcano. Arsia Mons is the dark, oval feature near the limb, just to the left of the 'T' in the 'Tharsis Montes' label. The dark, nearly circular feature above the 'S' in 'Tharsis' is the volcano, Pavonis Mons, and the other dark circular feature, above and to the right of 's' in 'Montes,' is Ascraeus Mons. Illumination is from the left/lower left.

Season: Northern Autumn/Southern Spring

More South Polar "Swiss Cheese"

NASA Image and Video Library

2000-04-24

This image is illuminated by sunlight from the upper left. Some of the surface of the residual south polar cap has a pattern that resembles that of sliced, swiss cheese. Shown here at the very start of southern spring is a frost-covered surface in which there are two layers evident--a brighter upper layer into which are set swiss cheese-like holes, and a darker, lower layer that lies beneath the "swiss cheese" pattern. Nothing like this exists anywhere on Mars except within the south polar cap. This is a Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image acquired on August 2, 1999. It is located near 84.8°S, 71.8°W, and covers an area 3 km across and about 6.1 km long (1.9 by 3.8 miles). http://photojournal.jpl.nasa.gov/catalog/PIA02368

Exhuming South Polar Crater

NASA Technical Reports Server (NTRS)

2004-01-01

7 February 2004 The large, circular feature in this image is an old meteor impact crater. The crater is larger than the 3 kilometers-wide (1.9 miles-wide) Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image, thus only part of the crater is seen. The bright mesas full of pits and holes--in some areas resembling swiss cheese--are composed of frozen carbon dioxide. In this summertime view, the mesa slopes and pit walls are darkened as sunlight causes some of the ice to sublime away. At one time in the past, the crater shown here may have been completely covered with carbon dioxide ice, but, over time, it has been exhumed as the ice sublimes a little bit more each summer. The crater is located near 86.8oS, 111.6oW. Sunlight illuminates this scene from the upper left.

Small Impact Crater

NASA Technical Reports Server (NTRS)

2005-01-01

22 June 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a small impact crater with a 'butterfly' ejecta pattern. The butterfly pattern results from an oblique impact. Not all oblique impacts result in an elliptical crater, but they can result in a non-radial pattern of ejecta distribution. The two-toned nature of the ejecta -- with dark material near the crater and brighter material further away -- might indicate the nature of subsurface materials. Below the surface, there may be a layer of lighter-toned material, underlain by a layer of darker material. The impact throws these materials out in a pattern that reflects the nature of the underlying layers.

Location near: 3.7oN, 348.2oW Image width: 3 km (1.9 mi) Illumination from: lower left Season: Northern Autumn

Argyre Dust Devil Tracks

NASA Technical Reports Server (NTRS)

2003-01-01

MGS MOC Release No. MOC2-363, 17 May 2003

This summertime Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) view of the floor of Argyre Basin shows a plethora of dark streaks thought to have been created by the passage of dust devils. Dust devils are vortices of wind--just as a tornado is a vortex of wind associated with stormy weather on Earth, and the spiraling of water down a bathtub drain is a vortex in a liquid. Dust devils usually form on Mars on relatively calm, quiet, spring and summer afternoons. The passage of a dust devil picks up and disturbs the thin coatings of dust on the martian surface, forming streaks that mark the path that the moving dust devil took. This picture covers an area 3 km (1.9 mi) wide and is located near 48.5oS, 43.0oW. Sunlight illuminates the scene from the upper left.

Mars South Polar Cap 'Fingerprint' Terrain

NASA Technical Reports Server (NTRS)

2000-01-01

This picture is illuminated by sunlight from the upper left.

Some portions of the martian south polar residual cap have long, somewhat curved troughs instead of circular pits. These appear to form in a layer of material that may be different than that in which 'swiss cheese' circles and pits form, and none of these features has any analog in the north polar cap or elsewhere on Mars. This picture shows the 'fingerprint' terrain as a series of long, narrow depressions considered to have formed by collapse and widening by sublimation of ice. Unlike the north polar cap, the south polar region stays cold enough in summer to retain frozen carbon dioxide. Viking Orbiter observations during the late 1970s showed that very little water vapor comes off the south polar cap during summer, indicating that any frozen water that might be there remains solid throughout the year.

This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image was obtained in early southern spring on August 4, 1999. It shows an area 3 x 5 kilometers (1.9 x 3.1 miles) at a resolution of about 7.3 meters (24 ft) per pixel. Located near 86.0oS, 53.9oW.

Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

Evidence for Recent Liquid Water on Mars:'Weeping' Layer in Gorgonum Chaos

NASA Technical Reports Server (NTRS)

2000-01-01

[figure removed for brevity, see original site]

This image, acquired by the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) in May 2000 shows numerous examples of martian gullies that all start--or head--in a specific layer roughly a hundred meters beneath the surface of Mars. These features are located on the south-facing wall of a trough in the Gorgonum Chaos region, an area found to have many examples of gullies proposed to have formed by seepage and runoff of liquid water in recent martian times.

The layer from which the gullies emanate has recessed backward to form an overhang beneath a harder layer of rock. The larger gullies have formed an alcove--an area above the overhang from which debris has collapsed to leave a dark-toned scar. Below the layer of seepage is found a dark, narrow channel that runs down the slope to an apron of debris. The small, bright, parallel features at the base of the cliff at the center-right of the picture is a series of large windblown ripples.

Although the dark tone of the alcoves and channels in this image is not likely to be the result of wet ground (the contrast in this image has been enhanced), it does suggest that water has seeped out of the ground and moved down the slope quite recently. Sharp contrasts between dark and light areas are hard to maintain on Mars for very long periods of time because dust tends to coat surfaces and reduce brightness differences. To keep dust from settling on a surface, it has to have undergone some process of erosion (wind, landslides, water runoff) relatively recently. There is no way to know how recent this activity was, but educated guesses center between a few to tens of years, and it is entirely possible that the area shown in this image has water seeping out of the ground today.

Centered near 37.9oS, 170.2oW, sunlight illuminates the MOC image from the upper left, north is toward the upper right. The context view above is from the Viking 1 orbiter and was acquired in 1977. The Viking picture is illuminated from the upper right; north is up. The small white box in the context frame shows the location of the high resolution MOC view.

Ripples on Cratered Terrain North of Hesperia Planum

NASA Technical Reports Server (NTRS)

1999-01-01

This is a Mars Orbiter Camera view of the cratered uplands located between the Amenthes Fossae and Hesperia Planum. This ancient, cratered surface sports a covering of windblown dunes and ripples oriented in somewhat different directions. The dunes are bigger and their crests generally run east-west across the image. The ripples are smaller and their crests run in a more north-south direction. The pattern they create together makes some of the dunes almost appear as if they are giant millipedes!This picture covers an area only 3 kilometers (1.9 miles) wide. Illumination is from the top.

Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

Possible Juventae Chasma subice volcanic eruptions and Maja Valles ice outburst floods on Mars: Implications of Mars Global surveyor crater densities, geomorphology, and topography

USGS Publications Warehouse

Chapman, M.G.; Gudmundsson, M.T.; Russell, A.J.; Hare, T.M.

2003-01-01

This article discusses image, topographic, and spectral data from the Mars Global Surveyor (MGS) mission that provide new information concerning the surface age, geomorphology, and topography of the Juventae Chasma/Maja Valles system. Our study utilizes data from two instruments on board MGS: images from the Mars Orbiter Camera (MOC) and topography from the Mars Orbiter Laser Altimeter (MOLA). Within Maja Valles we can now observe depositional bars with megaripples that unequivocally show catastrophic floods occurred in the channel. Viking impact crater densities indicated the chasma and channel floor areas were all one age (late Hesperian to Amazonian); however, MOC data indicate a marked difference in densities of small craters between Juventae Chasma, Maja Valles, and the channel debouchment area in Chryse Planitia basin. Although other processes may contribute to crater variability, young resurfacing events in the chasma and episodes of recent erosion at Maja Valles channel head may possibly account for the disparate crater densities along the chasma/channel system. Relatively young volcanic eruptions may have contributed to resurfacing; as in Juventae Chasma, a small possible volcanic cone of young dark material is observed. MOC data also indicate previously unknown interior layered deposit mounds in the chasma that indicate at least two periods of mound formation. Finally, MOLA topography shows that the entire floor of the chasma lies at the same elevation as the channel debouchment area in Chryse basin, resulting in a 3-km-high barrier to water flow out of the chasma. Blocked ponded water would rapidly freeze in the current (and likely past) climate of Mars. For catastrophic flow to occur in Maja Valles, some process is required to melt ice and induce floods out of the chasma. We suggest subice volcanic eruption and calculate estimates of water discharges and volumes that these eruptions might have produced.

Mars Eolian Geology at Airphoto Scales: The Large Wind Streaks of Western Arabia Terra

NASA Technical Reports Server (NTRS)

Edgett, Kenneth S.

2001-01-01

More than 27,000 pictures at aerial photograph scales (1.5-12 m/pixel) have been acquired by the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) since September 1997. The pictures are valuable for testing hypotheses about geologic history and processes of Mars. Of particular interest are eolian features connected to surface albedo patterns. This work is focused on low-albedo wind streaks, some over 100 km long, in western Arabia Terra. Each streak is widest where it originates at an impact crater (typically 25-150 km diameter). The streaks taper downwind. Within the associated craters there is a lower-albedo surface that, in nearly all observed cases, includes barchan dunes indicative of transport in the same direction as the wind streaks. Upwind of the dunes there is usually an outcrop of layered material that might have served as a source for dune sand. MOC images show that the west Arabia streaks consist of a smooth-surfaced, multiple-meters-thick, mantle (smooth at 1.5 m/pixel) that appears to be superposed on local surfaces. No dunes are present, indicating that down-streak transport of sediment via saltation and traction have not occurred. Two models might explain the observed properties: (1) the streaks consist of dark silt- and clay-sized grains deflated from the adjacent crater interiors and deposited from suspension or (2) they are remnants (protected in the lee of impact crater rims) of a formerly much larger, regional covering of low albedo, smooth-surfaced mantle. The latter hypothesis is based on observation of low albedo mantled surfaces occurring south of west Arabia in Terra Meridiani. For reasons yet unknown, a large fraction of the martian equatorial regions are covered by low albedo, mesa-forming material that lies unconformably atop eroded layered and cratered terrain. Both hypotheses are being explored via continued selective targeting of new MOC images as well as analyses of the new data.

Medusae Fossae Formation - High Resolution Image

NASA Technical Reports Server (NTRS)

1998-01-01

An exotic terrain of wind-eroded ridges and residual smooth surfaces are seen in one of the highest resolution images ever taken of Mars from orbit. The Medusae Fossae formation is believed to be formed of the fragmental ejecta of huge explosive volcanic eruptions. When subjected to intense wind-blasting over hundreds of millions of years, this material erodes easily once the uppermost tougher crust is breached. The crust, or cap rock, can be seen in the upper right part of the picture. The finely-spaced ridges are similar to features on Earth called yardangs, which are formed by intense winds plucking individual grains from, and by wind-driven sand blasting particles off, sedimentary deposits.

The image was taken on October 30, 1997 at 11:05 AM PST, shortly after the Mars Global Surveyor spacecraft's 31st closest approach to Mars. The image covers an area 3.6 X 21.5 km (2.2 X 13.4 miles) at 3.6 m (12 feet) per picture element--craters only 11 m (36 feet, about the size of a swimming pool) across can be seen. The best Viking view of the area (VO 1 387S34) has a resolution of 240 m/pixel, or 67 times lower resolution than the MOC frame.

Malin Space Science Systems (MSSS) and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

The Defrosting South

NASA Technical Reports Server (NTRS)

2005-01-01

20 August 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows varied springtime patterns formed in defrosting, seasonal carbon dioxide frost in the south polar region of Mars. The feature sporting an outline of dark spots and an interior of smaller, closely-spaced dark spots and dark-outlined polygons is a patch of windblown or wind-eroded sand that was covered by carbon dioxide frost during the previous autumn and winter. The fainter, larger polygon pattern on either side of the patch of defrosting sand is formed in the substrate upon which the sand patch is sitting. Polygonal forms such as these might indicate the presence of ice below the surface.

Location near: 79.6oS, 125.0oW Image width: width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Spring

Carbon Dioxide Landforms

NASA Technical Reports Server (NTRS)

2004-01-01

19 March 2004 The martian south polar residual ice cap is mostly made of frozen carbon dioxide. There is no place on Earth that a person can go to see the landforms that would be produced by erosion and sublimation of hundreds or thousands of cubic kilometers of carbon dioxide. Thus, the south polar cap of Mars is as alien as alien can get. This image, acquired in February 2004 by the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC), shows how the cap appears in summer as carbon dioxide is subliming away, creating a wild pattern of pits, mesas, and buttes. Darker surfaces may be areas where the ice contains impurities, such as dust, or where the surface has been roughened by the removal of ice. This image is located near 86.3oS, 0.8oW. This picture covers an area about 3 km (1.9 mi) across. Sunlight illuminates the scene from the top/upper left.

Moonshine Versus Earthshine: Physics Makes a Difference

NASA Technical Reports Server (NTRS)

Wilson, T. L.

2005-01-01

Introduction: Recently released, high-resolution images from the Mars Orbiter Camera (MOC) and the Thermal Emission Imaging System (THEMIS) reveal a myriad of intriguing landforms banked along the northern edge of Terby Crater located on the northern rim of Hellas (approx.28degS, 287degW). Landforms within this crater include north-trending troughs and ridges, a remarkable 2.5 km-thick sequence of exposed layers, mantled ramps that extend across and between layered sequences, fan-like structures, sinuous channels, collapse pits, a massive landslide and viscous flow features. The suite of diverse landforms in Terby and its immediate surroundings attest to a diversity of rock types and geologic processes, making this locality ideal for studying landform-climate relationships on Mars. In order to decipher the complicated geologic history of Terby Crater and the nature of the layered deposits, a generalized geomorphic map was created and the slope of the layered deposits was examined.

Chryse 'Alien Head'

NASA Technical Reports Server (NTRS)

2005-01-01

26 January 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows an impact crater in Chryse Planitia, not too far from the Viking 1 lander site, that to seems to resemble a bug-eyed head. The two odd depressions at the north end of the crater (the 'eyes') may have formed by wind or water erosion. This region has been modified by both processes, with water action occurring in the distant past via floods that poured across western Chryse Planitia from Maja Valles, and wind action common occurrence in more recent history. This crater is located near 22.5oN, 47.9oW. The 150 meter scale bar is about 164 yards long. Sunlight illuminates the scene from the left/lower left.

Tracking Boulders

NASA Technical Reports Server (NTRS)

2006-01-01

13 March 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a portion of a trough in the Sirenum Fossae region. On the floor and walls of the trough, large -- truck- to house-sized -- boulders are observed at rest. However, there is evidence in this image for the potential for mobility. In the central portion of the south (bottom) wall, a faint line of depressions extends from near the middle of the wall, down to the rippled trough floor, ending very near one of the many boulders in the area. This line of depressions is a boulder track; it indicates the path followed by the boulder as it trundled downslope and eventually came to rest on the trough floor. Because it is on Mars, even when the boulder is sitting still, this once-rolling stone gathers no moss.

Location near: 29.4oS, 146.6oW Image width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Summer

Meridiani Bedrock

NASA Technical Reports Server (NTRS)

2004-01-01

23 December 2004 The Mars Exploration Rover (MER-B), Opportunity, spent much of this year exploring outcrops of light-toned, layered, sedimentary rock that occur just beneath the dark plains of Sinus Meridiani. To access these rocks, the rover had to look at the walls and rims of impact craters. Further to the north and east of where the rover landed, similar rocks outcrop at the surface -- in other words, they are not covered by dark sand and granules as they are at the rover site. This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows an example from eastern Sinus Meridiani. All of the light-toned surfaces in this image are outcrops of ancient sedimentary rock. Similar rocks probably occur beneath the low albedo (dark) materials that mantle the lower-elevation surfaces in this area. This picture is located near 0.5oS, 356.7oW. The image covers an area about 3 km (1.9 mi) wide and sunlight illuminates the scene from the upper left.

The Edge

NASA Technical Reports Server (NTRS)

2006-01-01

6 April 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows the edge (running diagonally from the lower left to the upper right) of a trough, which is part of a large pit crater complex in Noachis Terra. This type of trough forms through the collapse of surface materials into the subsurface, and often begins as a series of individual pit craters. Over time, continued collapse increases the diameter of individual pits until finally, adjacent pits merge to form a trough such as the one captured in this image. The deep shadowed area is caused in part by an overhang; layered rock beneath this overhang is less resistant to erosion, and thus has retreated tens of meters backward, beneath the overhang. A person could walk up inside this 'cave' formed by the overhanging layered material.

Location near: 47.0oS, 355.7oW Image width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Summer

Ten-Meter Scale Topography and Roughness of Mars Exploration Rovers Landing Sites and Martian Polar Regions

NASA Technical Reports Server (NTRS)

Ivanov, Anton B.

2003-01-01

The Mars Orbiter Camera (MOC) has been operating on board of the Mars Global Surveyor (MGS) spacecraft since 1998. It consists of three cameras - Red and Blue Wide Angle cameras (FOV=140 deg.) and Narrow Angle camera (FOV=0.44 deg.). The Wide Angle camera allows surface resolution down to 230 m/pixel and the Narrow Angle camera - down to 1.5 m/pixel. This work is a continuation of the project, which we have reported previously. Since then we have refined and improved our stereo correlation algorithm and have processed many more stereo pairs. We will discuss results of our stereo pair analysis located in the Mars Exploration rovers (MER) landing sites and address feasibility of recovering topography from stereo pairs (especially in the polar regions), taken during MGS 'Relay-16' mode.

Layered Outcrops of Far West Candor Chasma

NASA Technical Reports Server (NTRS)

2000-01-01

[figure removed for brevity, see original site]

Images from Mariner 9 in 1972 revealed that some of the mesas and mounds found within the chasms of the martian 'Grand Canyon'--the Valles Marineris--have layers in them. Speculations as to the origin of these interior layered materials ranged from volcanic ash deposits to sediments laid down in lakes that could have partially filled the Vallis Marineris troughs, much as lakes now occupy portions of the rift valleys of eastern Africa. The proposal that the Valles Marineris once hosted deep martian lakes led to additional speculation as to the prospects for finding fossil evidence of martian life.

Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) images have ten or more times better resolution than the Mariner 9 and Viking orbiter images taken in the 1970s. MOC images have indeed confirmed the presence of layered outcrops within the Valles Marineris. They have also shown places previously not suspected to have layered rock, and they have shown that these materials might not have formed in the Valles Marineris, but were instead deposited in craters that were subsequently buried long before the chasms opened up (see discussion below). The layered rock is now visible because of faulting and erosion.

The high resolution picture shown here (B, above right) was the first image received by MOC scientists that began to hint at a larger story of layered sedimentary rock on Mars. The picture shows a 1.5 km by 2.9 km (0.9 mi by 1.8 mi) area in far southwestern Candor Chasma (A, above left) that was--based on Mariner 9 and Viking orbiter images--not previously expected to exhibit layers. The MOC image reveals that the floor of western Candor Chasma at this location is indeed layered. What is most striking about the picture is the large number and uniformity of the layers, or beds. There are over 100 beds in this area, and each has about the same thickness (estimated to be about 10 meters (11 yards) thick). Each layer has a relatively smooth upper surface, and each is hard enough to form steep cliffs at its margins.

Layers indicate change. The uniform pattern seen here--beds of similar properties and thickness repeated over a hundred times--suggest that the deposition of materials that made the layers was interrupted at regular or episodic intervals. Patterns like this, when found on Earth, usually indicate the presence of sediment deposited in dynamic, energetic, underwater environments. On Mars, these same patterns could very well indicate that the materials were deposited in a lake or shallow sea. Other MOC images suggest that these layers would not have formed in a lake in Candor Chasma, but instead were deposited in a crater or other basin that existed before Candor Chasma was cut (by faulting and erosion) into the surrounding terrain. However, it is not known for certain that these materials actually formed underwater, for it is possible that there were uniquely Martian processes occurring in the distant past that would mimic the pattern of sedimentation in water. For example, if the early Martian atmosphere was denser than it is today, and if the planet's atmospheric pressure changed on a cyclic basis (as it does today), then perhaps these materials are simply deposits of airborne dust that were later buried and cemented to create cliff-forming rock.

Sunlight illuminates both the wide angle context view and the narrow angle high resolution image from the left/upper left. In both, north is toward the top and east to the right.

Active and Recent Volcanism and Hydrogeothermal Activity on Mars

NASA Astrophysics Data System (ADS)

Edgett, Kenneth S.; Cantor, B. A.; Harrison, T. N.; Kennedy, M. R.; Lipkaman, L. J.; Malin, M. C.; Posiolova, L. V.; Shean, D. E.

2010-10-01

There are no active volcanoes or geysers on Mars today, nor in the very recent past. Since 1997, we have sought evidence from targeted narrow angle camera images and daily, global wide angle images for active or very recent (decades to < 10 Ma) volcanism or hydrogeothermal events on Mars. Despite > 11 years of daily global imaging and coverage of > 60% of Mars at ≤ 6 m/pixel (with the remaining < 40% largely outside of volcanic regions), we have found no such evidence, although one lava field in Aeolis (5°N, 220°W) stands out as possibly the site of the most recent volcanism. Authors of impact crater size-frequency studies suggest some volcanic landforms on Mars are as young as tens to hundreds of Ma. This interpreted youth has implications for understanding the internal geophysical state of Mars and has encouraged those seeking sources for trace gases (methane) in the atmosphere and those seeking "warm havens for life” (Jakosky 1996, New Scientist 150, 38-42). We targeted thousands of Mars Global Surveyor (MGS) MOC and Mars Reconnaissance Orbiter (MRO) CTX (and HiRISE) images to examine volcanic regions; we also studied every MGS MOC and MRO MARCI wide angle image. For evidence of active volcanism, we sought eruption plumes, new vents, new tephra deposits, and new volcanogenic flows not observed in earlier images. For recent volcanism, we sought volcanogenic flows with zero or few superposed impact craters and minimal regolith development or superposed eolian sediment. Targets included all volcanic landforms identified in research papers as "recent” as well as areas speculated to have exhibited eruptive plumes. An independent search for endogenic heat sources, a key Mars Odyssey THEMIS objective, has also not produced a positive result (Christensen et al. 2005, P24A-01, Eos, Trans. Am. Geophys. Union 86/52).

Something Old, Something New

NASA Technical Reports Server (NTRS)

2006-01-01

20 September 2006 When it was launched in 1996, the plan was that Mars Global Surveyor (MGS) would wrap up its mission in 2000. Damage to a hinge connected to a solar panel slowed the orbit insertion aerobraking process by a year, so in 1997 the spacecraft team determined that MGS's mission would end in early 2001. However, the spacecraft and its instruments remained healthy, and its mission was extended. And extended. And extended again. And again. MGS has now been orbiting the red planet for just over nine years. Throughout the mission, data from the Mars Orbiter Camera (MOC) have emphasized details about some of the very oldest and the very newest features exposed on the planet's surface.

The very ancient and the modern come together in this small, approximately 3 km by 3 km (1.9 mi by 1.9 mi) area on the floor of an unnamed impact crater in western Arabia Terra.

Old are the light-toned, layered mounds scattered across the image. The layers form stair-steps leading to the top of each mound. In most cases, the 'steps' are not clean, but are instead covered with debris eroded from the next layer, or step, above. The mounds are remnants of layered rock that once covered the entire scene. They were deposited as sediment in the large, unnamed crater in which these landforms occur. Their regular thickness and repeated character suggest that episodic, or perhaps cyclic, processes brought sediment to the crater floor. If the crater contained water at the time the sediments were deposited, then they represent lakebed materials. The processes that (a) brought sediment to this site, (b) cemented the sediment to form rock, and (c) eroded the sediment to form the mounds we see today, all occurred at some time in the distant past.

New are the dark-toned sand dunes and intermediate-toned ripples. The dark dunes were formed of sand that in relatively recent times has been blown by wind from the northeast (upper right) toward the southwest (lower left). The dunes have slowly encroached upon the older, light-toned, layered mounds. Surrounding each mound is a suite of intermediate-toned ripples. These are large ripples, relative to counterparts on Earth, and are most likely made up of grains somewhat coarser than sand, typically of several millimeters in size. The ripples form a pattern that is generally radial to each mound, indicating that they formed in winds that interacted with these topographic obstacles. The dark dunes are generally younger than the ripples, as dark sand has encroached upon and over-ridden some of the ripples.

This image is one of the favorites of the MOC operations team at Malin Space Science Systems, because it is not only pretty, it also emphasizes aspects of both the ancient and modern sedimentary processes and materials on Mars. Sediments, sedimentary rocks, and the environments in which they were deposited have been a key theme of the MOC science investigation from the beginning, more than 20 years ago, when MOC was selected by NASA to be built and sent to Mars. The first MOC was aboard Mars Observer when it was lost in 1993; the second MOC was built for MGS and is still operating today.

Location near: 8.8oN, 1.2oW Image width: 3 km (1.9 mi) Illumination from: lower left Season: Northern Winter

Light-Toned, Layered Outcrops of Northern Terra Meridiani Mars: Viking, Phobos 2, and Mars Global Surveyor Observations

NASA Technical Reports Server (NTRS)

Edgett, Kenneth S.

2002-01-01

Locating outcrops of sedimentary rock on Mars is an important step toward deciphering the planet's geologic and climatologic record. Sedimentary rock representing the earliest martian environments, are of particular interest in this context. This is a report about a vast exposure of material proposed to be martian sedimentary rock. The outcrops cover an area (approximately sq 300,000 km) roughly the size of the Colorado Plateau in North America (approximately 260,000 sq km). The materials occur in northern Terra Meridiani, near of one of the four sites being considered for a 2004 NASA Mars Exploration Rover (MER) landing. The landing ellipse, centered at deg S, deg W, lies in a region exhibiting smooth and rough (at meter scale) dark-toned surfaces, with scattered light-toned patches. Stratigraphically, the dark-toned materials at the MER site lie unconformably on top of a previously-eroded, light-toned surface; the light-toned patches in the landing ellipse are geologic windows down to this lower stratigraphic unit. North of the landing ellipse, the light-toned materials are well-exposed because the darker materials have been removed, stranding outlier remnants in a few locations. The light-toned materials are layered, vertically heterogeneous, and exhibit lateral continuity over hundreds of kilometers. Eroded layers produce cliffs; some outcrops are expressed as mesas, buttes, and spires; and impact craters ranging in diameter from a few meters to tens of kilometers are interbedded with the layers. The purpose of this report is to summarize the results of greater than 6 years of photogeologic investigation into the nature of the light-toned outcrops of northern Terra Meridiani. The work is a 'snapshot' of progress made toward eventual geologic mapping and establishment of the stratigraphic sequence for the materials through 30 September 2002, a day prior to the first release of Mars Odyssey Thermal Emission Imaging System (THEMIS) data to the NASA Planetary Data System (PDS). The main body of data examined were Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) images acquired through 30 September 2002. The data also 2 include Viking orbiter images, a Phobos 2 Termoscan image, MGS Mars Orbiter Laser Altimeter (MOLA) topographic observations, and the products of published Viking Infrared Thermal Mapper (IRTM) and Mars Global Surveyor (MGS) Thermal Emission Spectrometer (TES) analyses. Through September 2002, over 126,000 MOC images had been acquired, and greater than 600 of the MOC narrow angle (1.5-12 m/pixel) images occur within the portions of Terra Meridiani and southwestern Arabia Terra.

Identifying Surface Changes on HRSC Images of the Mars South Polar Residual CAP (sprc)

NASA Astrophysics Data System (ADS)

Putri, Alfiah Rizky Diana; Sidiropoulos, Panagiotis; Muller, Jan-Peter

2016-06-01

The surface of Mars has been an object of interest for planetary research since the launch of Mariner 4 in 1964. Since then different cameras such as the Viking Visual Imaging Subsystem (VIS), Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC), and Mars Reconnaissance Orbiter (MRO) Context Camera (CTX) and High Resolution Imaging Science Experiment (HiRISE) have been imaging its surface at ever higher resolution. The High Resolution Stereo Camera (HRSC) on board of the European Space Agency (ESA) Mars Express, has been imaging the Martian surface, since 25th December 2003 until the present-day. HRSC has covered 100 % of the surface of Mars, about 70 % of the surface with panchromatic images at 10-20 m/pixel, and about 98 % at better than 100 m/pixel (Neukum et. al., 2004), including the polar regions of Mars. The Mars polar regions have been studied intensively recently by analysing images taken by the Mars Express and MRO missions (Plaut et al., 2007). The South Polar Residual Cap (SPRC) does not change very much in volume overall but there are numerous examples of dynamic phenomena associated with seasonal changes in the atmosphere. In particular, we can examine the time variation of layers of solid carbon dioxide and water ice with dust deposition (Bibring, 2004), spider-like channels (Piqueux et al., 2003) and so-called Swiss Cheese Terrain (Titus et al., 2004). Because of seasonal changes each Martian year, due to the sublimation and deposition of water and CO2 ice on the Martian south polar region, clearly identifiable surface changes occur in otherwise permanently icy region. In this research, good quality HRSC images of the Mars South Polar region are processed based on previous identification as the optimal coverage of clear surfaces (Campbell et al., 2015). HRSC images of the Martian South Pole are categorized in terms of quality, time, and location to find overlapping areas, processed into high quality Digital Terrain Models (DTMs) and Orthorectified Images (ORIs) and projected into polar stereographic projection using DLR (Deutsches Zentrum für Luft- und Raumfahrt; German Aerospace Center)'s VICAR and GIS software with modifications developed by Kim & Muller (2009). Surface changes are identified in the Mars SPRC region and analysed based on their appearance in the HRSC images.

MGS MOC Returns to Service Following Solar Conjunction Hiatus

NASA Technical Reports Server (NTRS)

2000-01-01

PIA01043 PIA01044

Many aspects of our studies of Mars from Earth are dictated by the different rates at which the two planets orbit the Sun. This difference allows Earth to pass Mars in its orbit, continue to lead Mars around the Sun, and then eventually overtake Mars again, every 26 months. This cycle governs opportunities to send rockets to Mars when the closest approaches between the two planets occur (opposition). The cycle also dictates when Mars will pass behind the Sun relative to Earth (conjunction). A Solar Conjunction period has just ended. During this time radio communications from the Mars Global Surveyor spacecraft, operating at Mars, were interrupted for a few weeks. Because it would not be able to send pictures back to Earth during this time, the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) was turned off on June 21, 2000, and turned back on again July 13, 2000. The two pictures shown here are among the very first high resolution views of the martian surface that were received following the resumed operation of the MOC. Both pictures arrived on Earth via radio downlink on Saturday, July 15, 2000.

The first picture (above left) shows a ridged and cratered plain in southern Hesperia Planum around 32.8oS, 243.2oW. The second image (above right) shows the layered northeastern wall of a meteor impact crater in Noachis Terra at 32.9oS, 357.6oW. Both pictures cover an area 3 kilometers (1.9 miles) wide at a resolution of 6 meters per pixel. Both are illuminated by sunlight from the upper left.

Analysis of dark albedo features on a southern polar dune field of Mars.

PubMed

Horváth, András; Kereszturi, Akos; Bérczi, Szaniszló; Sik, András; Pócs, Tamás; Gánti, Tibor; Szathmáry, Eörs

2009-01-01

We observed 20-200 m sized low-albedo seepage-like streaks and their annual change on defrosting polar dunes in the southern hemisphere of Mars, based on the Mars Orbiter Camera (MOC), High Resolution Stereo Camera (HRSC), and High Resolution Imaging Science Experiment (HiRISE) images. The structures originate from dark spots and can be described as elongated or flowlike and, at places, branching streaks. They frequently have another spotlike structure at their end. Their overall appearance and the correlation between their morphometric parameters suggest that some material is transported downward from the spots and accumulates at the bottom of the dune's slopes. Here, we present possible scenarios for the origin of such streaks, including dry avalanche, liquid CO(2), liquid H(2)O, and gas-phase CO(2). Based on their morphology and the currently known surface conditions of Mars, no model interprets the streaks satisfactorily. The best interpretation of only the morphology and morphometric characteristics is only given by the model that implies some liquid water. The latest HiRISE images are also promising and suggest liquid flow. We suggest, with better knowledge of sub-ice temperatures that result from extended polar solar insolation and the heat insulator capacity of water vapor and water ice, future models and measurements may show that ephemeral water could appear and flow under the surface ice layer on the dunes today.

Localization, Localization, Localization

NASA Technical Reports Server (NTRS)

Parker, T.; Malin, M.; Golombek, M.; Duxbury, T.; Johnson, A.; Guinn, J.; McElrath, T.; Kirk, R.; Archinal, B.; Soderblom, L.

2004-01-01

Localization of the two Mars Exploration Rovers involved three independent approaches to place the landers with respect to the surface of Mars and to refine the location of those points on the surface with the Mars control net: 1) Track the spacecraft through entry, descent, and landing, then refine the final roll stop position by radio tracking and comparison to images taken during descent; 2) Locate features on the horizon imaged by the two rovers and compare them to the MOC and THEMIS VIS images, and the DIMES images on the two MER landers; and 3) 'Check' and refine locations by acquisition of MOC 1.5 meter and 50 cm/pixel images.

Polygon/Cracked Sedimentary Rock

NASA Technical Reports Server (NTRS)

2004-01-01

4 December 2004 Exposures of sedimentary rock are quite common on the surface of Mars. Less common, but found in many craters in the regions north and northwest of the giant basin, Hellas, are sedimentary rocks with distinct polygonal cracks in them. This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows an example from the floor of an unnamed crater near 21.0oS, 311.9oW. Such cracks might have formed by desiccation as an ancient lake dried up, or they might be related to ground ice freeze/thaw cycles or some other stresses placed on the original sediment or the rock after it became lithified. The 300 meter scale bar is about 328 yards long. The scene is illuminated by sunlight from the upper left.

Extreme Rock Distributions on Mars and Implications for Landing Safety

NASA Technical Reports Server (NTRS)

Golombek, M. P.

2001-01-01

Prior to the landing of Mars Pathfinder, the size-frequency distribution of rocks from the two Viking landing sites and Earth analog surfaces was used to derive a size-frequency model, for nomimal rock distributions on Mars. This work, coupled with extensive testing of the Pathfinder airbag landing system, allowed an estimate of what total rock abundances derived from thermal differencing techniques could be considered safe for landing. Predictions based on this model proved largely correct at predicting the size-frequency distribution of rocks at the Mars Pathfinder site and the fraction of potentially hazardous rocks. In this abstract, extreme rock distributions observed in Mars Orbiter Camera (MOC) images are compared with those observed at the three landing sites and model distributions as an additional constraint on potentially hazardous surfaces on Mars.

Barchan Dunes

NASA Technical Reports Server (NTRS)

2004-01-01

28 April 2004 One of the simplest forms a sand dune can take is the barchan. The term, apparently, comes from the Arabic word for crescent-shaped dunes. They form in areas with a single dominant wind direction that are also not overly-abundant in sand. The barchan dunes shown here were imaged in March 2004 by the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) as it passed over a crater in western Arabia Terra near 21.1oN, 17.6oW. The horns and steep slope on each dune, known as the slip face, point toward the south, indicating prevailing winds from the north (top). The picture covers an area about 3 km (1.9 mi) across and is illuminated by sunlight from the lower left.

Windblown Sand in West Candor

NASA Technical Reports Server (NTRS)

2004-01-01

23 December 2003

West Candor Chasma, a part of the vast Valles Marineris trough system, is known for its layered sedimentary rock outcrops. It is less known for dark fields of windblown sand, but that is what occurs in the north-central part of the chasm. This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image, obtained in December 2003, shows the interplay of dark, wind-blown sand with buttes and mesas of layered rock in west Candor Chasma. Dark streamers of sand point toward the east/southeast (right/lower right), indicating that dominant winds blow from the west. This picture is located near 5.2oS, 75.7oW, and covers an area 3 km (1.9 mi) wide. Sunlight illuminates the scene from the lower left.

Thermal Inertia of Rocks and Rock Populations and Implications for Landing Hazards on Mars

NASA Technical Reports Server (NTRS)

Golombek, M. P.; Jakosky, B. M.; Mellon, M. T.

2001-01-01

Rocks represent an obvious potential hazard to a landing spacecraft. They also represent an impediment to rover travel and objects of prime scientific interest. Although Mars Orbiter Camera (MOC) images are of high enough resolution to distinguish the largest rocks (an extremely small population several meters diameter or larger), traditionally the abundance and distribution of rocks on Mars have been inferred from thermal inertia and radar measurements, our meager ground truth sampling of landing sites, and terrestrial rock populations. In this abstract, we explore the effective thermal inertia of rocks and rock populations, interpret the results in terms of abundances and populations of potentially hazardous rocks, and conclude with interpretations of rock hazards on the Martian surface and in extremely high thermal inertia areas.

Tikhonravov's Eyebrows

NASA Technical Reports Server (NTRS)

2005-01-01

1 January 2004 This red wide angle Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows Tikhonravov Crater in central Arabia Terra. The crater is about 386 km (240 mi) in diameter and presents two impact craters at its center that have dark patches of sand in them, giving the impression of pupils in two eyes. North (above) each of these two craters lies a dark-toned patch of surface material, providing the impression of eyebrows. M. K. Tikhonravov was a leading Russian rocket engineer in the 20th Century. The crater named for him, despite its large size, is still partly buried, on its west side, beneath the heavily cratered terrain of Arabia Terra. The center of Tikhonravov is near 13.5oN, 324.2oW. Sunlight illuminates the scene from the upper left.

The Terrain of Margaritifer Chaos

NASA Technical Reports Server (NTRS)

1999-01-01

The jumbled and broken terrain in the picture on the left is known as chaotic terrain. Chaotic terrain was first observed in Mariner 6 and 7 images of Mars more than 30 years ago, and is thought to result from collapse after material--perhaps water or ice--was removed from the subsurface by events such as the formation of giant flood channels. The region shown here is named 'Margaritifer Chaos'. The left picture is a Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) red wide angle camera context frame that covers an area 115 km (71 miles) across. The small white box is centered at 10.3oS, 21.4oW and indicates the location of the high-resolution view on the right. The high resolution view (right) covers a small portion of the Margaritifer Chaos at 1.8 meters (6 feet) per pixel. The area shown is 3 km (1.9 miles) across. Uplands are lumpy with small bright outcrops of bedrock. Lowlands or valleys in the chaotic terrain have floors covered by light-toned windblown d rifts. This image is typical of the very highest-resolution views of the equatorial latitudes of Mars. Both pictures are illuminated from the left/upper left, north is toward the top.

A Mid-Summer's Dust Devil

NASA Technical Reports Server (NTRS)

2001-01-01

One objective for the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) in the Extended Mission is to continue looking for changes and dynamic events taking place on the red planet. The feature shown here elicited gasps of excitement among the MOC Operations Staff when it was received in early April 2001.

The feature is a dust devil. Dust devils are spinning, columnar vortices of wind that move across the landscape, pick up dust, and look somewhat like miniature tornadoes. Dust devils are a common occurrence in dry and desert landscapes on Earth as well as Mars. When this dust devil was spied in Amazonis Planitia on April 10th, the MOC was looking straight down. Usually when the camera is looking down the dust devil will appear as a circular, fuzzy patch with a straight shadow indicating its columnar shape. In this case, however, the dust devil is somewhat curved and kinked--its shape is best seen in the shadow it casts to the right. A thin, light-toned track has been left by the dust devil as it moved eastward across the landscape. Usually, such tracks are darker than the surroundings, in this case the light tone might indicate that the dust being removed by the passing dust devil is darker than the surface underneath the thin veneer of dust.

Dust devils most typically form when the ground heats up during the day, warming the air immediately above the surface. As the warmed air nearest the surface begins to rise, it spins. The spinning column begins to move across the surface and picks up loose dust (if any is present). The dust makes the vortex visible and gives it the 'dust devil' or tornado-like appearance. This dust devil occurred at an optimal time for dust devils whether on Earth or Mars--around 2 p.m. local time in the middle of Northern Hemisphere Summer. North is up, sunlight illuminates the scene from the left (west), and 500 meters is about 547 yards. The shadow cast by the dust devil goes off the edge of the image, but the length shown here (about 1.5 km) indicates that the dust devil was a bit more than 1 km (0.62 mi) in height.

Comparing wind directions inferred from Martian dust devil tracks analysis with those predicted by the Mars Climate Database

NASA Astrophysics Data System (ADS)

Statella, T.; Pina, P.; Silva, E. A.; Nervis Frigeri, Ary Vinicius; Neto, Frederico Gallon

2016-10-01

We have calculated the prevailing dust devil tracks direction as a means of verifying the Mars Climate Database (MCD) predicted wind directions accuracy. For that purpose we have applied an automatic method based on morphological openings for inferring the prevailing tracks direction in a dataset comprising 200 Mars Orbiter Camera (MOC) Narrow Angle (NA) and High Resolution Imaging Science Experiment (HiRISE) images of the Martian surface, depicting regions in the Aeolis, Eridania, Noachis, Argyre and Hellas quadrangles. The prevailing local wind directions were calculated from the MCD predicted speeds for the WE and SN wind components. The results showed that the MCD may not be able to predict accurately the locally dominant wind direction near the surface. In adittion, we confirm that the surface wind stress alone cannot produce dust lifting in the studied sites, since it never exceeds the threshold value of 0.0225 Nm-2 in the MCD.

Sub-ice volcanoes and ancient oceans/lakes: A Martian challenge

USGS Publications Warehouse

Chapman, M.G.

2003-01-01

New instruments on board the Mars Global Surveyor (MGS) spacecraft began providing accurate, high-resolution image and topography data from the planet in 1997. Though data from the Mars Orbiter Laser Altimeter (MOLA) are consistent with hypotheses that suggest large standing bodies of water/ice in the northern lowlands in the planet's past history, Mars Orbiter Camera (MOC) images acquired to test these hypotheses have provided negative or ambiguous results. In the absence of classic coastal features to test the paleo-ocean hypothesis, other indicators need to be examined. Tuyas and hyaloclastic ridges are subice volcanoes of unique appearance that form in ponded water conditions on Earth. Features with similar characteristics occur on Mars. MOLA analyses of these Martian features provide estimates of the height of putative ice/water columns at the edge of the Utopia Planitia basin and within Ophir Chasma of Valles Marineris, and support the hypotheses of a northern ocean on Mars. ?? 2003 Elsevier Science B.V. All rights reserved.

Frost-free North Polar Layers in the Good Old Summertime

NASA Technical Reports Server (NTRS)

2006-01-01

17 October 2006 The middle portion of the northern summer season is the ideal time of year to capture relatively dust- and haze-free views of martian north polar terrain. This year, much more of the north polar cap has sublimed away than has been evident in previous northern summers going back to 1999, when Mars Global Surveyor (MGS) began the Mapping Phase of the mission. This MGS Mars Orbiter Camera (MOC) image shows a nearly ice-free view of layers exposed by erosion in the north polar region. The light-toned patches are remnants of water ice frost. The layers are generally considered by the Mars scientific community to be record of past depositions of ice and dust. This picture is located near 82.5oN, 118.6oW, and covers an area about 3 km by 10 km (1.9 by 6.2 miles). Sunlight illuminates the scene from the upper left; the image was acquired on 22 September 2006.

EU-FP7-iMARS: Analysis of Mars Multi-Resolution Images Using Auto-Coregistration Data Mining and Crowd Source Techniques: Processed Results - a First Look

NASA Astrophysics Data System (ADS)

Muller, Jan-Peter; Tao, Yu; Sidiropoulos, Panagiotis; Gwinner, Klaus; Willner, Konrad; Fanara, Lida; Waehlisch, Marita; van Gasselt, Stephan; Walter, Sebastian; Steikert, Ralf; Schreiner, Bjoern; Ivanov, Anton; Cantini, Federico; Wardlaw, Jessica; Morley, Jeremy; Sprinks, James; Giordano, Michele; Marsh, Stuart; Kim, Jungrack; Houghton, Robert; Bamford, Steven

2016-06-01

Understanding planetary atmosphere-surface exchange and extra-terrestrial-surface formation processes within our Solar System is one of the fundamental goals of planetary science research. There has been a revolution in planetary surface observations over the last 15 years, especially in 3D imaging of surface shape. This has led to the ability to overlay image data and derived information from different epochs, back in time to the mid 1970s, to examine changes through time, such as the recent discovery of mass movement, tracking inter-year seasonal changes and looking for occurrences of fresh craters. Within the EU FP-7 iMars project, we have developed a fully automated multi-resolution DTM processing chain, called the Coregistration ASP-Gotcha Optimised (CASP-GO), based on the open source NASA Ames Stereo Pipeline (ASP) [Tao et al., this conference], which is being applied to the production of planetwide DTMs and ORIs (OrthoRectified Images) from CTX and HiRISE. Alongside the production of individual strip CTX & HiRISE DTMs & ORIs, DLR [Gwinner et al., 2015] have processed HRSC mosaics of ORIs and DTMs for complete areas in a consistent manner using photogrammetric bundle block adjustment techniques. A novel automated co-registration and orthorectification chain has been developed by [Sidiropoulos & Muller, this conference]. Using the HRSC map products (both mosaics and orbital strips) as a map-base it is being applied to many of the 400,000 level-1 EDR images taken by the 4 NASA orbital cameras. In particular, the NASA Viking Orbiter camera (VO), Mars Orbiter Camera (MOC), Context Camera (CTX) as well as the High Resolution Imaging Science Experiment (HiRISE) back to 1976. A webGIS has been developed [van Gasselt et al., this conference] for displaying this time sequence of imagery and will be demonstrated showing an example from one of the HRSC quadrangle map-sheets. Automated quality control [Sidiropoulos & Muller, 2015] techniques are applied to screen for suitable images and these are extended to detect temporal changes in features on the surface such as mass movements, streaks, spiders, impact craters, CO2 geysers and Swiss Cheese terrain. For result verification these data mining techniques are then being employed within a citizen science project within the Zooniverse family. Examples of data mining and its verification will be presented.

Recent Movements: New Landslides in Less than 1 Martian Year

NASA Technical Reports Server (NTRS)

2000-01-01

Changes between 1 February 1998 and 18 November 1999

Crater at 6oS, 184oW on 01 FEB 1998 [figure removed for brevity, see original site]

3-D Anaglyph View--PIA02380 [figure removed for brevity, see original site]

What is happening on Mars right now? Pictures that show changes occurring from time to time give some clues as to what processes are shaping the modern martian landscape. Dust devils, dust storms, and polar frosts are all known to cause change sin the surface every martian year. But what about other geologic processes? How 'active' is Mars today? The Mars Orbiter Camera (MOC) onboard the Mars Global Surveyor (MGS) has been in orbit long enough that it is starting to provide some answers. MGS began orbiting Mars in September 1997. Since that time, it has seen the planet cycle through more than 1 of its 687-Earth-days-long years. The pictures shown here document changes observed by the MOC caused by small landslides.

The picture at the lower left (above) shows a shallow crater located near Apollinaris Patera at 6oS, 184oW, that was photographed by MOC in February 1998. The walls of this crater exhibit approximately 100 dark streaks running down its slopes. These streaks have formed as small landslides or avalanches and are probably composed of sand and/or silt. The image is illuminated by sunlight from the lower left, and the crater is about 5 kilometers (3 miles) across. The white box shows the location of a section of the crater that was photographed again in mid-November 1999, about 92% of a Martian Year later.

The top picture shows a comparison of the southeastern crater wall as it appeared on February 1, 1998, and again on November 18, 1999. (Note that the picture has been rotated relative to the context image at lower left). During the time between the two images, three new dark slope streaks formed (arrows, top right). The older streaks are lighter and fainter than these new, dark ones, suggesting that streaks fade with time. This means that, at least for the crater walls shown here, any streak that is dark is younger than any streak that is pale. The stereo anaglyph (requires red-blue '3-d glasses') at the lower right uses the two images of the crater rim to provide a 3-dimensional view. The anaglyph is helpful to see that the dark streaks really do occur on a slope. In addition, by viewing the anaglyph without 3-d glasses, one can easily identify the three new streaks because they appear as blue and have no red counterpart.

These three new slope streaks formed sometime between February 1998 and November 1999. Similar streaks were observed in the highest-resolution images from the Viking orbiters in the late 1970s, but for more than 20 years no one has known how recent these features might be, or how often they might form. Now, MOC is providing some exciting answers.

Synergism of the method of characteristics and CAD technology for neutron transport calculation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, Z.; Wang, D.; He, T.

2013-07-01

The method of characteristics (MOC) is a very popular methodology in neutron transport calculation and numerical simulation in recent decades for its unique advantages. One of the key problems determining whether the MOC can be applied in complicated and highly heterogeneous geometry is how to combine an effective geometry processing method with MOC. Most of the existing MOC codes describe the geometry by lines and arcs with extensive input data, such as circles, ellipses, regular polygons and combination of them. Thus they have difficulty in geometry modeling, background meshing and ray tracing for complicated geometry domains. In this study, amore » new idea making use of a CAD solid modeler MCAM which is a CAD/Image-based Automatic Modeling Program for Neutronics and Radiation Transport developed by FDS Team in China was introduced for geometry modeling and ray tracing of particle transport to remove these geometrical limitations mentioned above. The diamond-difference scheme was applied to MOC to reduce the spatial discretization error of the flat flux approximation in theory. Based on MCAM and MOC, a new MOC code was developed and integrated into SuperMC system, which is a Super Multi-function Computational system for neutronics and radiation simulation. The numerical testing results demonstrated the feasibility and effectiveness of the new idea for geometry treatment in SuperMC. (authors)« less

Martian 'Swiss Cheese'

NASA Technical Reports Server (NTRS)

2000-01-01

This image is illuminated by sunlight from the upper left.

Looking like pieces of sliced and broken swiss cheese, the upper layer of the martian south polar residual cap has been eroded, leaving flat-topped mesas into which are set circular depressions such as those shown here. The circular features are depressions, not hills. The largest mesas here stand about 4 meters (13 feet) high and may be composed of frozen carbon dioxide and/or water. Nothing like this has ever been seen anywhere on Mars except within the south polar cap, leading to some speculation that these landforms may have something to do with the carbon dioxide thought to be frozen in the south polar region. On Earth, we know frozen carbon dioxide as 'dry ice'. On Mars, as this picture might be suggesting, there may be entire landforms larger than a small town and taller than 2 to 3 men and women that consist, in part, of dry ice.

No one knows for certain whether frozen carbon dioxide has played a role in the creation of the 'swiss cheese' and other bizarre landforms seen in this picture. The picture covers an area 3 x 9 kilometers (1.9 x 5.6 miles) near 85.6oS, 74.4oW at a resolution of 7.3 meters (24 feet) per pixel. This picture was taken by the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) during early southern spring on August 3, 1999.

Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

A 3-D Look at Wind-Sculpted Ridges in Aeolis

NASA Technical Reports Server (NTRS)

2000-01-01

Layers of bedrock etched by wind to form sharp, elongated ridges known to geomorphologists as yardangs are commonplace in the southern Elysium Planitia/southern Amazonis region of Mars. The ridges shown in this 3-D composite of two overlapping Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) images occur in the eastern Aeolis region of southern Elysium Planitia near 2.3oS, 206.8oW. To view the picture in stereo, you need red-blue 3-D glasses (red filter over the left eye, blue over the right). For wind to erode bedrock into the patterns seen here, the rock usually must consist of something that is fine-grained and of nearly uniform grain size, such as sand. It must also be relatively easy to erode. For decades, most Mars researchers have interpreted these materials to be eroded deposits of volcanic ash. Nothing in the new picture shown here can support nor refute this earlier speculation. The entire area is mantled by light-toned dust. Small landslides within this thin dust layer form dark streaks on some of the steeper slopes in this picture (for more examples and explanations for these streaks, see previous web pages listed below).

The stereo (3-D) picture was compiled using an off-nadir view taken by the MOC during the Aerobrake-1 subphase of the mission in January 1998 with a nadir (straight-down-looking) view acquired in October 2000. The total area shown is about 6.7 kilometers (4.2 miles) wide by 2.5 kilometers (1.5 miles) high and is illuminated by sunlight from the upper right. The relief in the stereo image is quite exaggerated: the ridges are between about 50 and 100 meters (about 165-330 feet) high. North is toward the lower right.

Monitoring the perennial martian northern polar cap with MGS MOC

NASA Astrophysics Data System (ADS)

Hale, A. Snyder; Bass, D. S.; Tamppari, L. K.

2005-04-01

We have used the Mars Global Surveyor Mars Orbiter Camera Wide Angle (MGS MOC WA) dataset to study albedo trends on the martian northern residual cap. Six study regions were selected, the Chasma Boreale source region, three regions near the center of the cap ("fish hook" region, latitude = 87°; "bottle opener" region, latitude = 87°, "steep-shallow" region, latitude = 85°), and two lower latitude regions (crater, latitude = 77°, and polar outlier, latitude = 82°), and the albedos of these six regions were examined. These regions were chosen due to their good temporal coverage in the MOC dataset, as well as having been studied by other researchers (Bass et al., 2000, Icarus 144, 382-396; Calvin and Titus, 2004, Lunar Planet. Sci. XXXV, Abstract 1455). The picture which emerges is complex. Most areas experience a combination of darkening and brightening through the northern summer; only one area consistently brightens (the polar outlier region). A good deal of interannual repeatability in each region's albedo behavior is seen, however. Possible causes for the observed complex behaviors include dust deposition from late summer storms, sintering of frost grains over the course of the summer, and cold trapping of volatiles on bright, cold surfaces.

Formation of Martian Gullies by the Action of Liquid Water Flowing Under Current Martian Environmental Conditions

NASA Technical Reports Server (NTRS)

Heldmann, J. L.; Toon, O. B.; Pollard, W. H.; Mellon, M. T.; Pitlick, J.; McKay, C. P.; Andersen, D. T.

2005-01-01

Images from the Mars Orbiter Camera (MOC) on the Mars Global Surveyor (MGS) spacecraft show geologically young small-scale features resembling terrestrial water-carved gullies. An improved understanding of these features has the potential to reveal important information about the hydrological system on Mars, which is of general interest to the planetary science community as well as the field of astrobiology and the search for life on Mars. The young geologic age of these gullies is often thought to be a paradox because liquid water is unstable at the Martian surface. Current temperatures and pressures are generally below the triple point of water (273 K, 6.1 mbar) so that liquid water will spontaneously boil and/or freeze. We therefore examine the flow of water on Mars to determine what conditions are consistent with the observed features of the gullies.

Landslide in Kasei Valles

NASA Technical Reports Server (NTRS)

2003-01-01

The Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) continues in 2003 to return excellent, high resolution images of the red planet's surface. This nearly 1.5 meters (5 ft.) per pixel view of a landslide on a 200 meter-high (219 yards-high) slope in Kasei Valles was specifically targeted for scientific investigation by rotating the MGS spacecraft about 7.8o off-nadir in January 2003. The scar left by the landslide reveals layers in the bedrock at the top the slope and shows a plethora of dark-toned, house-sized boulders that rolled down the slope and collected at the base of the landslide scar. A few meteor impact craters have formed on the landslide deposit and within the scar, indicating that this landslide occurred a very long time ago. Sunlight illuminates this scene from the left/lower left; the landslide is located near 28.3oN, 71.9oW.

Basaltic Ring Structures as an Analog for Ring Features in Athabasca Valles, Mars

NASA Technical Reports Server (NTRS)

Jaeger, W. L.; Keszthelyi, L. P.; Burr, D. M.; Emery, J. P.; Baker, V. R.; McEwen, A. S.; Miyamoto, H.

2005-01-01

Basaltic ring structures (BRSs) are enigmatic, quasi-circular landforms in eastern Washington State that were first recognized in 1965. They remained a subject of geologic scrutiny through the 1970 s and subsequently faded from the spotlight, but recent Mars Orbiter Camera (MOC) images showing morphologically similar structures in Athabasca Valles, Mars, have sparked renewed interest in BRSs. The only known BRSs occur in the Channeled Scabland, a region where catastrophic Pleistocene floods from glacial Lake Missoula eroded into the Miocene flood basalts of the Columbia Plateau. The geologic setting of the martian ring structures (MRSs) is similar; Athabasca Valles is a young channel system that formed when catastrophic aqueous floods carved into a volcanic substrate. This study investigates the formation of terrestrial BRSs and examines the extent to which they are appropriate analogs for the MRSs in Athabasca Valles.

Small-scale martian polygonal terrain: Implications for liquid surface water

USGS Publications Warehouse

Seibert, N.M.; Kargel, J.S.

2001-01-01

Images from the Mars Orbiter Camera (MOC) through August 1999 were analyzed for the global distribution of small-scale polygonal terrain not clearly resolved in Viking Orbiter imagery. With very few exceptions, small-scale polygonal terrain occurs at middle to high latitudes of the northern and southern hemisphere in Hesperian-age geologic units. The largest concentration of this terrain occurs in the Utopia basin in close association with scalloped depressions (interpreted as thermokarst) and appears to represent an Amazonia event. The morphology and occurence of small polygonal terrain suggest they are either mud desiccation cracks or ice-wedge polygons. Because the small-scale polygons in Utopia and Argyre Planitiae are associated with other cold-climate permafrost or glacial features, an ice-wedge model is preferred for these areas. Both cracking mechanisms work most effectively in water- or ice-rich finegrained material and may imply the seasonal or episodic existence of liquid water at the surface.

Photoelectron imaging spectroscopy of MoC{sup −} and NbN{sup −} diatomic anions: A comparative study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, Qing-Yu; Li, Zi-Yu; He, Sheng-Gui, E-mail: shengguihe@iccas.ac.cn, E-mail: chenh@iccas.ac.cn

2015-04-28

The isoeletronic diatomic MoC{sup −} and NbN{sup −} anions have been prepared by laser ablation and studied by photoelectron imaging spectroscopy combined with quantum chemistry calculations. The photoelectron spectra of NbN{sup −} can be very well assigned on the basis of literature reported optical spectroscopy of NbN. In contrast, the photoelectron spectra of MoC{sup −} are rather complex and the assignments suffered from the presence of many electronically hot bands and limited information from the reported optical spectroscopy of MoC. The electron affinities of NbN and MoC have been determined to be 1.450 ± 0.003 eV and 1.360  ±  0.003more » eV, respectively. The good resolution of the imaging spectroscopy provided a chance to resolve the Ω splittings of the X{sup 3}Σ{sup −} (Ω = 0 and 1) state of MoC and the X{sup 4}Σ{sup −} (Ω = 1/2 and 3/2) state of MoC{sup −} for the first time. The spin-orbit splittings of the X{sup 2}Δ state of NbN{sup −} and the a{sup 2}Δ state of MoC{sup −} were also determined. The similarities and differences between the electronic structures of the NbN and MoC systems were discussed.« less

Defrosting Polar Dunes--"They Look Like Bushes!"

NASA Image and Video Library

2000-05-26

"They look like bushes!" That's what almost everyone says when they see the dark features found in pictures taken of sand dunes in the polar regions as they are beginning to defrost after a long, cold winter. It is hard to escape the fact that, at first glance, these images acquired by the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) over both polar regions during the spring and summer seasons, do indeed resemble aerial photographs of sand dune fields on Earth -- complete with vegetation growing on and around them! Of course, this is not what the features are, as we describe below and in related picture captions. Still, don't they look like vegetation to you? Shown here are two views of the same MGS MOC image. On the left is the full scene, on the right is an expanded view of a portion of the scene on the left. The bright, smooth surfaces that are dotted with occasional, nearly triangular dark spots are sand dunes covered by winter frost. The MGS MOC has been used over the past several months (April-August 1999) to monitor dark spots as they form and evolve on polar dune surfaces. The dark spots typically appear first along the lower margins of a dune -- similar to the position of bushes and tufts of grass that occur in and among some sand dunes on Earth. Because the martian air pressure is very low -- 100 times lower than at Sea Level on Earth -- ice on Mars does not melt and become liquid when it warms up. Instead, ice sublimes -- that is, it changes directly from solid to gas, just as "dry ice" does on Earth. As polar dunes emerge from the months-long winter night, and first become exposed to sunlight, the bright winter frost and snow begins to sublime. This process is not uniform everywhere on a dune, but begins in small spots and then over several months it spreads until the entire dune is spotted like a leopard. The early stages of the defrosting process -- as in the picture shown here -- give the impression that something is "growing" on the dunes. The sand underneath the frost is dark, just like basalt beach sand in Hawaii. Once it is exposed to sunlight, the dark sand probably absorbs sunlight and helps speed the defrosting of each sand dune. This picture was taken by MGS MOC on July 21, 1999. The dunes are located in the south polar region and are expected to be completely defrosted by November or December 1999. North is approximately up, and sunlight illuminates the scene from the upper left. The 500 meter scale bar equals 547 yards; the 300 meter scale is also 328 yards. http://photojournal.jpl.nasa.gov/catalog/PIA02300

Residual Cap

NASA Image and Video Library

2006-05-10

This MOC image shows a summertime view of the south polar residual cap of Mars. In this image, mesas composed largely of solid carbon dioxide are separated from one another by irregularly-shaped depressions

Mars global digital dune database: MC-30

USGS Publications Warehouse

Hayward, R.K.; Fenton, L.K.; Titus, T.N.; Colaprete, A.; Christensen, P.R.

2012-01-01

The Mars Global Digital Dune Database (MGD3) provides data and describes the methodology used in creating the global database of moderate- to large-size dune fields on Mars. The database is being released in a series of U.S. Geological Survey Open-File Reports. The first report (Hayward and others, 2007) included dune fields from lat 65° N. to 65° S. (http://pubs.usgs.gov/of/2007/1158/). The second report (Hayward and others, 2010) included dune fields from lat 60° N. to 90° N. (http://pubs.usgs.gov/of/2010/1170/). This report encompasses ~75,000 km2 of mapped dune fields from lat 60° to 90° S. The dune fields included in this global database were initially located using Mars Odyssey Thermal Emission Imaging System (THEMIS) Infrared (IR) images. In the previous two reports, some dune fields may have been unintentionally excluded for two reasons: (1) incomplete THEMIS IR (daytime) coverage may have caused us to exclude some moderate- to large-size dune fields or (2) resolution of THEMIS IR coverage (100 m/pixel) certainly caused us to exclude smaller dune fields. In this report, mapping is more complete. The Arizona State University THEMIS daytime IR mosaic provided complete IR coverage, and it is unlikely that we missed any large dune fields in the South Pole (SP) region. In addition, the increased availability of higher resolution images resulted in the inclusion of more small (~1 km2) sand dune fields and sand patches. To maintain consistency with the previous releases, we have identified the sand features that would not have been included in earlier releases. While the moderate to large dune fields in MGD3 are likely to constitute the largest compilation of sediment on the planet, we acknowledge that our database excludes numerous small dune fields and some moderate to large dune fields as well. Please note that the absence of mapped dune fields does not mean that dune fields do not exist and is not intended to imply a lack of saltating sand in other areas. Where availability and quality of THEMIS visible (VIS), Mars Orbiter Camera (MOC) narrow angle, Mars Express High Resolution Stereo Camera, or Mars Reconnaissance Orbiter Context Camera and High Resolution Imaging Science Experiment images allowed, we classified dunes and included some dune slipface measurements, which were derived from gross dune morphology and represent the approximate prevailing wind direction at the last time of significant dune modification. It was beyond the scope of this report to look at the detail needed to discern subtle dune modification. It was also beyond the scope of this report to measure all slipfaces. We attempted to include enough slipface measurements to represent the general circulation (as implied by gross dune morphology) and to give a sense of the complex nature of aeolian activity on Mars. The absence of slipface measurements in a given direction should not be taken as evidence that winds in that direction did not occur. When a dune field was located within a crater, the azimuth from crater centroid to dune field centroid was calculated, as another possible indicator of wind direction. Output from a general circulation model is also included. In addition to polygons locating dune fields, the database includes ~700 of the THEMIS VIS and MOC images that were used to build the database.

The Diversity of Martian Volcanic Features as Seen in MOC Images and MOLA Topographic Data

NASA Technical Reports Server (NTRS)

Mouginis-Mark, Peter J.

2004-01-01

This project focused on the evolution of the summit areas of Martian volcanoes. By using data collected from the Mars Orbiter Camera (MOC) and Mars Laser Altimeter (MOLA) instruments, we tried to better understand the diversity of constructional volcanism on Mars, and hence further understand eruption processes. We investigated the styles of volcanism on the major volcanic constructs (Olympus, Arsia, Pavonis, and Ascraeus Montes), and also studied the role of magma-volatile interactions within the shallow subsurface of these volcanoes and the surrounding areas. Theoretical models for internal processes within volcanoes, including the thermal influences of dike intrusions on pre-existing volatiles, were developed based on our identification of landform distributions. Our work provided new insights into the diversity of volcanism on Mars, and the distribution of Martian volatiles in space and time. Highlights of our results include: 1) The identification of large ash deposits at the summit of Arsia Mons; 2) The study of a large flank eruption on Elysium Mons and the estimation of the effusion rate needed to produce the observed lava channel; 3) The quantitative description of dike intrusion into volatile-rich terrain to explain the origin of Hrad Vallis; 4) The identification of constructional ridges on top of very young lava flows from Olympus Mons, with the interpretation that these ridges were formed by very recent phreatomagmatic eruptions; and 5) The characterization of the dimensions and slope distributions on 18 volcanic edifices on Mars.

Thermophysical properties of the MER and Beagle II landing site regions on Mars

NASA Astrophysics Data System (ADS)

Jakosky, Bruce M.; Hynek, Brian M.; Pelkey, Shannon M.; Mellon, Michael T.; Martínez-Alonso, Sara; Putzig, Nathaniel E.; Murphy, Nate; Christensen, Philip R.

2006-08-01

We analyzed remote-sensing observations of the Isidis Basin, Gusev Crater, and Meridiani Planum landing sites for Beagle II, MER-A Spirit, and MER-B Opportunity spacecraft, respectively. We emphasized the thermophysical properties using daytime and nighttime radiance measurements from the Mars Global Surveyor (MGS) Thermal Emission Spectrometer and Mars Odyssey Thermal Emission Imaging System (THEMIS) and thermal inertias derived from nighttime data sets. THEMIS visible images, MGS Mars Orbiter Camera (MOC) narrow-angle images, and MGS Mars Orbiter Laser Altimeter (MOLA) data are incorporated as well. Additionally, the remote-sensing data were compared with ground-truth at the MER sites. The Isidis Basin surface layer has been shaped by aeolian processes and erosion by slope winds coming off of the southern highlands and funneling through notches between massifs. In the Gusev region, surface materials of contrasting thermophysical properties have been interpreted as rocks or bedrock, duricrust, and dust deposits; these are consistent with a complex geological history dominated by volcanic and aeolian processes. At Meridiani Planum the many layers having different thermophysical and erosional properties suggest periodic deposition of differing sedimentological facies possibly related to clast size, grain orientation and packing, or mineralogy.

Post Impact Mars Climate Simulations Using a GCM

NASA Technical Reports Server (NTRS)

Colaprete, A.; Haberle, R. M.; Segura, T. L.; Toon, O. B.; Zahnle, K.

2003-01-01

The first images returned by the Mariner 7 spacecraft of the Martian surface showed a landscape heavily scared by impacts. Mariner 9 imaging revealed geomorphic features including valley networks and outflow channels that suggest liquid water once flowed at the surface of Mars. Further evidence for water erosion and surface modification has come from the Viking Spacecraft, Mars Pathfinder and Mars Global Surveyor's (MGS) Mars Obiter Camera (MOC). This evidence includes apparent paleolake beds, fluvial fans and sedimentary layers (Cabrol and Grinn, 1999; Heberle et al., 2001). There is evidence for subsurface water as well. Rampart crates suggest an abundance of water in the near surface regolith (Mouginis-Mark, 1986). The estimated erosion rates necessary to explain the observed surface morphologies (Golombek and Bridges, 2000) present a conundrum. The rates of erosion appear to be highest when the early sun was fainter and only 75% as luminous as it is today. Furthermore the rates of erosion appear to correlate with the rate at which Mars was impacted (Carr and Waenke, 1992). All of this evidence suggests to a very different climate than what exists on Mars today.

Reuyl Crater Dust Avalanches

NASA Technical Reports Server (NTRS)

2002-01-01

(Released 13 May 2002) The Science The rugged, arcuate rim of the 90 km crater Reuyl dominates this THEMIS image. Reuyl crater is at the southern edge of a region known to be blanketed in thick dust based on its high albedo (brightness) and low thermal inertia values. This thick mantle of dust creates the appearance of snow covered mountains in the image. Like snow accumulation on Earth, Martian dust can become so thick that it eventually slides down the face of steep slopes, creating runaway avalanches of dust. In the center of this image about 1/3 of the way down is evidence of this phenomenon. A few dozen dark streaks can be seen on the bright, sunlit slopes of the crater rim. The narrow streaks extend downslope following the local topography in a manner very similar to snow avalanches on Earth. But unlike their terrestrial counterparts, no accumulation occurs at the bottom. The dust particles are so small that they are easily launched into the thin atmosphere where they remain suspended and ultimately blow away. The apparent darkness of the avalanche scars is due to the presence of relatively dark underlying material that becomes exposed following the passage of the avalanche. Over time, new dust deposition occurs, brightening the scars until they fade into the background. Although dark slope streaks had been observed in Viking mission images, a clear understanding of this dynamic phenomenon wasn't possible until the much higher resolution images from the Mars Global Surveyor MOC camera revealed the details. MOC images also showed that new avalanches have occurred during the time MGS has been in orbit. THEMIS images will allow additional mapping of their distribution and frequency, contributing new insights about Martian dust avalanches. The Story The stiff peaks in this image might remind you of the Alps here on Earth, but they really outline the choppy edge of a large Martian crater over 50 miles wide (seen in the context image at right). While these aren't the Alps, you will find quite a few avalanches. Avalanches of dust, however, not snow. Martian dust can become so thick in this area that it eventually slides down the steep slopes, creating runaway avalanches of dust. No dedicated, Swiss-like avalanche rescue teams would be needed much on Mars, however. Unlike snow, the dust doesn't pile up and accumulate at the bottom. Instead, dust particles are so small that they get launched into the atmosphere where they remain suspended until . . . poof! They are blown away and distributed lightly elsewhere. For evidence of past avalanches, check out the dark streaks running down the bright, sunlit slopes (western side of the peaks about 1/3 of the way down the image). These avalanche scars are dark because the underlying surface is not as bright as the removed dust. Eventually, new dust will settle over these scars, and the streaks will brighten until they fade into the background. The neat thing is that we'll be able to see all of these changes happening over time. Our current two Mars orbiters (called Mars Global Surveyor and 2001 Mars Odyssey) are showing that avalanche action is happening right now, all of the time on Mars. For example, the camera on Mars Global Surveyor has already taken pictures of the Martian surface in some areas that showed no avalanches - the first time the picture was snapped, that is. The next time around, the camera took a picture of the same area, only voila! New streaks, meaning new avalanches! That's why it can be so exciting to look at the Martian landscape over time to see how it changes. The THEMIS camera on Odyssey will continue to map out the places where the avalanches occur and how often. This information will really help scientists understand how dust is works to shape the terrain and to influence the Martian climate as it constantly swings into the atmosphere, falls down to the ground, and rises back up again. Stay tuned to see if you too can pick out the changes over time!

Distribution, morphology, and origins of Martian pit crater chains

NASA Astrophysics Data System (ADS)

Wyrick, Danielle; Ferrill, David A.; Morris, Alan P.; Colton, Shannon L.; Sims, Darrell W.

2004-06-01

Pit craters are circular to elliptical depressions found in alignments (chains), which in many cases coalesce into linear troughs. They are common on the surface of Mars and similar to features observed on Earth and other terrestrial bodies. Pit craters lack an elevated rim, ejecta deposits, or lava flows that are associated with impact craters or calderas. It is generally agreed that the pits are formed by collapse into a subsurface cavity or explosive eruption. Hypotheses regarding the formation of pit crater chains require development of a substantial subsurface void to accommodate collapse of the overlying material. Suggested mechanisms of formation include: collapsed lava tubes, dike swarms, collapsed magma chamber, substrate dissolution (analogous to terrestrial karst), fissuring beneath loose material, and dilational faulting. The research described here is intended to constrain current interpretations of pit crater chain formation by analyzing their distribution and morphology. The western hemisphere of Mars was systematically mapped using Mars Orbiter Camera (MOC) images to generate ArcView™ Geographic Information System (GIS) coverages. All visible pit crater chains were mapped, including their orientations and associations with other structures. We found that pit chains commonly occur in areas that show regional extension or local fissuring. There is a strong correlation between pit chains and fault-bounded grabens. Frequently, there are transitions along strike from (1) visible faulting to (2) faults and pits to (3) pits alone. We performed a detailed quantitative analysis of pit crater morphology using MOC narrow angle images, Thermal Emission Imaging System (THEMIS) visual images, and Mars Orbiter Laser Altimeter (MOLA) data. This allowed us to determine a pattern of pit chain evolution and calculate pit depth, slope, and volume. Volumes of approximately 150 pits from five areas were calculated to determine volume size distribution and regional trends. The information collected in the study was then compared with non-Martian examples of pit chains and physical analog models. We evaluated the various mechanisms for pit chain development based on the data collected and conclude that dilational normal faulting and sub-vertical fissuring provide the simplest and most comprehensive mechanisms to explain the regional associations, detailed geometry, and progression of pit chain development.

Evidence for Recent Liquid Water on Mars: Basic Features of Martian Gullies

NASA Technical Reports Server (NTRS)

2000-01-01

Water is the chief agent of weathering and erosion on Earth. Mars is a much drier, colder planet on which liquid water cannot exist very long at the surface because it will immediately begin to boil, evaporate, and freeze--all at the same time. However, new pictures from the Mars Orbiter Camera (MOC) onboard the Mars Global Surveyor (MGS) have provided an astonishing observation which suggests that liquid water may have played a role in shaping some recent gully-like features found on the slopes of various craters, troughs, and other depressions on the red planet.

These pictures introduce the basic features of a martian gully. The figure on the left is an example from Mars, the figure on the right is a gully on Earth. In the Earth picture, rain water flowing under and seeping along the base of a recently-deposited volcanic ash layer has created the gully. For Mars, water is not actually seen but is inferred from the landforms and their similarity to examples on Earth.

The landforms both on Earth and Mars are divided into three parts: the alcove, the channel, and the apron. Water seeps from between layers of rock on the wall of a cliff, crater, or other type of depression. The alcove forms above the site of seepage as water comes out of the ground and undermines the material from which it is seeping. The erosion of material at the site of seepage causes rock and debris on the slope above this area to collapse and slide downhill, creating the alcove.

The channel forms from water and debris running down the slope from the seepage area. The point where the top of the channel meets the bottom of the alcove is, in many cases, the site where seepage is occurring. Channels are probably flushed-clean of debris from time to time by large flash floods of water released from behind an ice barrier that might form at the site of seepage during more quiescent times.

The aprons are the down-slope deposits of ice and debris that were moved down the slope and through the channel. Whether any water--likely in the form of ice--persists in these deposits is unknown. The fact that the aprons do not go very far out onto the floors of craters and troughs (e.g., the foreground of the figure on the left) indicates that there is a limit as to how much water actually makes it to the bottom of the slope in liquid form. Most of the water by the time it reaches the bottom of the slope has probably either evaporated or frozen.

The MOC image on the left was acquired July 3, 1999, and is located on the south-facing wall of an impact crater near 54.8oS, 342.5oW. The MOC image is illuminated from the upper left; north is toward the upper right. The MOC image covers an area 1.3 km (0.8 mi) wide by 2 km (1.2 mi) long. The pictures from the flank of the Mount St. Helens volcano in Washington (right; large image and inset) were taken by MGSMOC Principal Investigator, Michael C. Malin, in the 1980s after the eruptions of May 1980. They are illuminated from the left; note footprints on left side of the picture for scale, also note the colored bar, which is 30 cm (11.8 in) long.

Mars Images MOC2-106 through 109

NASA Technical Reports Server (NTRS)

1999-01-01

Mars Global Surveyor images of the following are shown: Margin of lava flow in Daedalia Planum; Ripples in cratered terrain north of Hesperia Planum; Martian variety exhibited by the Olympica Fossae; and East Tithonium chasma wall, Valles Marineris.

Diversionary Tactic

NASA Image and Video Library

2006-08-16

This MOC image shows some dark slope streaks in the Phlegra Dorsa region of Mars. Of particular interest is the split streak near the center of the image, which diverted around a rounded hill as the material was sliding down the slope

The Martian Prime Meridian -- Longitude "Zero"

NASA Image and Video Library

2001-02-08

On Earth, the longitude of the Royal Observatory in Greenwich, England is defined as the "prime meridian," or the zero point of longitude. Locations on Earth are measured in degrees east or west from this position. The prime meridian was defined by international agreement in 1884 as the position of the large "transit circle," a telescope in the Observatory's Meridian Building. The transit circle was built by Sir George Biddell Airy, the 7th Astronomer Royal, in 1850. (While visual observations with transits were the basis of navigation until the space age, it is interesting to note that the current definition of the prime meridian is in reference to orbiting satellites and Very Long Baseline Interferometry (VLBI) measurements of distant radio sources such as quasars. This "International Reference Meridian" is now about 100 meters east of the Airy Transit at Greenwich.) For Mars, the prime meridian was first defined by the German astronomers W. Beer and J. H. Mädler in 1830-32. They used a small circular feature, which they designated "a," as a reference point to determine the rotation period of the planet. The Italian astronomer G. V. Schiaparelli, in his 1877 map of Mars, used this feature as the zero point of longitude. It was subsequently named Sinus Meridiani ("Middle Bay") by Camille Flammarion. When Mariner 9 mapped the planet at about 1 kilometer (0.62 mile) resolution in 1972, an extensive "control net" of locations was computed by Merton Davies of the RAND Corporation. Davies designated a 0.5-kilometer-wide crater (0.3 miles wide), subsequently named "Airy-0" (within the large crater Airy in Sinus Meridiani) as the longitude zero point. (Airy, of course, was named to commemorate the builder of the Greenwich transit.) This crater was imaged once by Mariner 9 (the 3rd picture taken on its 533rd orbit, 533B03) and once by the Viking 1 orbiter in 1978 (the 46th image on that spacecraft's 746th orbit, 746A46), and these two images were the basis of the martian longitude system for the rest of the 20th Century. The Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) has attempted to take a picture of Airy-0 on every close overflight since the beginning of the MGS mapping mission. It is a measure of the difficulty of hitting such a small target that nine attempts were required, since the spacecraft did not pass directly over Airy-0 until almost the end of the MGS primary mission, on orbit 8280 (January 13, 2001). In the left figure above, the outlines of the Mariner 9, Viking, and Mars Global Surveyor images are shown on a MOC wide angle context image, M23-00924. In the right figure, sections of each of the three images showing the crater Airy-0 are presented. A is a piece of the Mariner 9 image, B is from the Viking image, and C is from the MGS image. Airy-0 is the larger crater toward the top-center in each frame. The MOC observations of Airy-0 not only provide a detailed geological close-up of this historic reference feature, they will be used to improve our knowledge of the locations of all features on Mars, which will in turn enable more precise landings on the Red Planet by future spacecraft and explorers. http://photojournal.jpl.nasa.gov/catalog/PIA03207

Dust Devil Track Occurrence in Argyre Planitia.

NASA Astrophysics Data System (ADS)

Whelley, P. L.; Balme, M. R.; Greeley, R.

2002-12-01

Martian dust devil tracks were first observed in Viking Orbiter images [Thomas et al., 1985]. While the interpretation of these features was at first controversial, it is now widely accepted that the tracks are formed by the passage of small convective vortices (dust devils). As the dust devils travel across the surface the atmosphere is loaded with fine particles creating a visible trail inferred to be removal or deposition of material [Greeley et al., 2001]. Mars Global Surveyor (MGS) Mars Orbital Camera (MOC) images of dust devil tracks in Argyre Planitia were used to asses dust devil track abundance as a function of Martian season as well as elevation using Mars Orbiter Laser Altimeter (MOLA) data. Argyre Planitia is a large impact basin in the southern hemisphere (55° to 33°W and 35° to 58°S), with topographic relief of 7 km with the median at -1km. We have studied the 564 Narrow Angle MOC images (taken as of summer 2002) covering the area. The images were divided into two categories: those with devil tracks and those without. The Ls (solar longitude degrees as a fraction of orbit) and elevation of all of the images with and without devil tracks were noted. The elevation was recorded at the center point of each MOC image using MOLA data. A polar plot of all of the images shows a statistically random distribution throughout the Martian year. A context map of the images shows a representative distribution over the area of the crater itself. A polar plot of dust devil track occurrence within the area observed shows a major concentration of tracks between Ls 200° and 360° (southern spring to late summer). A seasonal breakdown of devil track occurrence as a percentage of total area observed yields: fall 11.25%, winter 2.24%, spring 27.21%, and summer 46.49%. We therefore conclude that dust devils tracks are formed preferentially in summer and are destroyed, fade or are covered, over a period of a few months. The elevation of all 564 images was measured and 1km bins were used to calculate the percent of occurrence. We discovered that, at 3km 0% of the observed area contain dust devil tracks, 2km 7.69%, 1km 12.90%, at Datum 15.95%, -1km 8.97%, -2km 28.92%, -3km% 50.00%, -4km 50.00%. Independent of the season a majority of the devil tracks were observed below -3km. Therefore elevation is a key factor governing the formation of dust devils or their ability to produce tracks. Our interpretation of these results is that dust devils are much more likely to form during the summer and, as suggested by recent experiments [Balme et al., 2002], that they are more efficient at moving materials on the surface in areas where the atmospheric pressure is greatest (in the lowest elevations). The short timescale for disappearance of tracks suggests that the distinct albedo variations of the tracks result from only the removal or deposition of a very thin layer of material. Thomas. P. et al., 1985, Science v. 230 Greeley. R. et al., 2001, LPSC XXXII Balme. M. et al., 2002, LPSC XXXIII

Transient bright "halos" on the South Polar Residual Cap of Mars: Implications for mass-balance

NASA Astrophysics Data System (ADS)

Becerra, Patricio; Byrne, Shane; Brown, Adrian J.

2015-05-01

Spacecraft imaging of Mars' south polar region during mid-southern summer of Mars year 28 (2007) observed bright halo-like features surrounding many of the pits, scarps and slopes of the heavily eroded carbon dioxide ice of the South Polar Residual Cap (SPRC). These features had not been observed before, and have not been observed since. We report on the results of an observational study of these halos, and spectral modeling of the SPRC surface at the time of their appearance. Image analysis was performed using data from MRO's Context Camera (CTX), and High Resolution Imaging Science Experiment (HiRISE), as well as images from Mars Global Surveyor's (MGS) Mars Orbiter Camera (MOC). Data from MRO's Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) were used for the spectral analysis of the SPRC ice at the time of the halos. These data were compared with a Hapke reflectance model of the surface to constrain their formation mechanism. We find that the unique appearance of the halos is intimately linked to a near-perihelion global dust storm that occurred shortly before they were observed. The combination of vigorous summertime sublimation of carbon dioxide ice from sloped surfaces on the SPRC and simultaneous settling of dust from the global storm, resulted in a sublimation wind that deflected settling dust particles away from the edges of these slopes, keeping these areas relatively free of dust compared to the rest of the cap. The fact that the halos were not exhumed in subsequent years indicates a positive mass-balance for flat portions of the SPRC in those years. A net accumulation mass-balance on flat surfaces of the SPRC is required to preserve the cap, as it is constantly being eroded by the expansion of the pits and scarps that populate its surface.

The type specimens of Tenthredo Linnaeus, 1758 (Hymenoptera: Tenthredinidae) deposited in the Hungarian Natural History Museum.

PubMed

Taeger, Andreas

2013-01-01

The type specimens of Tenthredo sensu lato deposited in the Hungarian Natural History Museum (Budapest) are reviewed. The following synonyms are recognized and discussed: Rhogogastera aenescens Mocsáry, 1909, syn. nov. of Tenthredo (Temuledo) finschi finschi W.F. Kirby, 1882; Macrophya prasinipes Konow, 1891, syn. nov. of Macrophya caucasica (Mocsáry, 1880); Tenthredo concinnoides Malaise, 1945, syn. nov. of Tenthredo concinna Mocsáry, 1883; Tenthredo fulviventris Mocsáry, 1909, syn. nov. of Tenthredo (Tenthredella) crenata (Enslin, 1912); Tenthredo vespa inaffectata Muche, 1965, syn. nov. of Tenthredo (Tenthredo) vespa Retzius, 1783; Rhogogaster kaszabi Zombori, 1973, syn. nov. of Tenthredo (Eurogaster) aaliensis (Strand, 1898); Tenthredo kaszabi Muche, 1965, syn. nov. of Tenthredo (Eurogaster) mesomela Linné, 1758; Rhogogastera opacella Mocsáry, 1909, syn. nov. of Tenthredo (Eurogaster) stulta Jakowlew, 1891; Tenthredo tschinggischanensis Muche, 1965 syn. nov. of Tenthredo (Tenthredella) balteata Klug, 1817; Tenthredo unfasciata Mocsáry, 1909, syn. nov. of Tenthredo (Tenthredella) colon Klug, 1817; Tenthredella cucullata Enslin, 1912, syn. nov. of Tenthredo (Tenthredella) colon Klug, 1817. Macrophya caucasica (Mocsáry, 1880) is a new combination (comb. nov.) for Allantus caucasicus Mocsáry, 1880. Tenthredo semicolon Mol, is a replacement name (nom. nov.) for Tenthredo punctulata Konow, 1887, nom. praeocc., nec Klug, 1817. Tenthredo chanae Taeger & Shinohara spec. nov., a species close to Tenthredo concinna, is described from Taiwan. Lectotypes are designated and illustrated for the following 30 nominal taxa: Rhogogastera aenescens Mocsáry, 1909; Allantus albiventris Mocsáry, 1880; Allantus almasyanus Mocsáry, 1909; Macrophya binaculata Mocsáry, 1909; Allantus brachycerus Mocsáry, 1909; Allantus caucasicus Mocsáry, 1880; Allantus centrorufus Mocsáry, 1909; Tenthredo chyzeri Mocsáry, 1891; Tenthredo concinna Mocsáry, 1883; Tenthredo concinnoides Malaise, 1945; Allantus eburneus Mocsáry, 1909; Allantus eburneus Mocsáry, 1909; Allantus fulvicornis Mocsáry, 1909; Tenthredo fulvicornis Mocsáry, 1909; Allantus fulvipennis Mocsáry, 1909; Tenthredo fulviventris Mocsáry, 1909; Tenthredo gribodoi Konow, 1898; Allantus lateralis Mocsáry, 1909; Allantus limbiferus Mocsáry, 1891; Allantus moestus Mocsáry, 1883; Rhogogastera nigrita Mocsáry, 1909; Allantus obesus Mocsáry, 1880; Macrophya prasinipes Konow, 1891; Tenthredo punctulata Konow, 1887; Allantus rufipes Mocsáry, 1909; Allantus sabariensis Mocsáry, 1880; Allantus sanguinolentus Mocsáry, 1909; Allantus temulus var. scutellatus Mocsáry, 1909; Allantus testaceus Mocsáry, 1909; Allantus variabilis Mocsáry, 1909. The first records of Tenthredo concinna for Vietnam and Nepal are given.

Inflated flows on Daedalia Planum (Mars)? Clues from a comparative analysis with the Payen volcanic complex (Argentina)

NASA Astrophysics Data System (ADS)

Giacomini, L.; Massironi, M.; Martellato, E.; Pasquarè, G.; Frigeri, A.; Cremonese, G.

2009-05-01

Inflation is an emplacement process of lava flows, where a thin visco-elastic layer, produced at an early stage, is later inflated by an underlying fluid core. The core remains hot and fluid for extended period of time due to the thermal-shield effect of the surface visco-elastic crust. Plentiful and widespread morphological fingerprints of inflation like tumuli and lava rises are found on the Payen volcanic complex (Argentina), where pahoehoe lava flows extend over the relatively flat surface of the Pampean foreland and reach at least 180 km in length. The morphology of the Argentinean Payen flows were compared with lava flows on Daedalia Planum (Mars), using Thermal Emission Imaging System (THEMIS), Mars Orbiter Laser Altimeter (MOLA), Mars Orbiter Camera (MOC), Mars Reconnaissance Orbiter (MRO)/High-Resolution Imaging Science Experiment (HiRISE). THEMIS images were used to map the main geological units of Daedalia Planum and determine their stratigraphic relationships. MOLA data were used to investigate the topographic surface over which the flows propagated and assess the thickness of lava flows. Finally, MOC and MRO/HIRISE images were used to identify inflations fingerprints and assess the cratering age of the Daedalia Planum' s youngest flow unit which were found to predate the caldera formation on top of the Arsia Mons. The identification of similar inflation features between the Daedalia Planum and the Payen lava fields suggests that moderate and long lasting effusion rates coupled with very efficient spreading processes could have cyclically occurred in the Arsia Mons volcano during its eruptive history. Consequently the effusion rates and rheological proprieties of Daedalia lava flows, which do not take into account the inflation process, can be overestimated. These findings raise some doubts about the effusion rates and lava rheological properties calculated on Martian flows and recommends that these should be used with caution if applied on flows not checked with high-resolution images and potentially affected by inflation. Further HiRISE data acquisition will permit additional analysis of the flow surfaces and will allow more accurate estimates of effusion rates and rheological properties of the lava flows on Mars particularly if this data is acquired under a favourable illumination.

Deflections in Lava Flow Directions Relative to Topography in the Tharsis Region: Indicators of Post-Flow Tectonic Motion

NASA Technical Reports Server (NTRS)

Chadwick, D. J.; Hughes, S. S.; Sakimoto, S. E. H.

2004-01-01

High-resolution topographic data for Mars from the Mars Orbiter Laser Altimeter (MOLA), and imagery from the Mars Orbiter Camera (MOC) and the Thermal Emission Imaging System (THEMIS) allow for the first accurate assessment of lava flow directions relative to topographic slopes in the Tharsis region. Tharisis has long been recognized as the dominant tectonic and volcanic province on the planet, with a complex geologic history. In this study, lava flow directions on Daedalia Planum, Syria Planum, Tempe Terra, and near the Tharsis Montes are compared with MOLA topographic contours to look for deviations of flow directions from the local slope direction. The topographic deviations identified in this study are likely due to Tharsis tectonic deformation that has modified the regional topography subsequent to the emplacement of the flows, and can be used to model the mechanisms and magnitudes of relatively recent tectonism in the region. A similar approach was used to identify possible postflow tectonic subsidence on the Snake River Plain in Idaho.

Deflections in Lava Flow Directions Relative to Topography in the Tharsis Region of Mars: Indications of Post-Flow Tectonic Motion

NASA Technical Reports Server (NTRS)

Chadwick, D. J.; Hughes, S. S.; Sakimoto, S. E. H.

2004-01-01

High-resolution topographic data from the Mars Orbiter Laser Altimeter (MOLA), and imagery from the Mars Orbiter Camera (MOC) and the Thermal Emission Imaging System (THEMIS) allow for the first accurate assessment of lava flow directions relative to topographic slopes in the Tharsis region. Tharisis has long been recognized as the dominant tectonic and volcanic province on the planet, with a complex geologic history. In this study, lava flow directions on Daedalia Planum, Syria Planum, Tempe Terra, and near the Tharsis Montes are compared with MOLA topographic contours to look for deviations of flow directions from the local slope direction. The topographic deviations identified in this study are likely due to Tharsis tectonic deformation that has modified the regional topography subsequent to the emplacement of the flows, and can be used to model the mechanisms and magnitudes of relatively recent tectonism in the region. A similar approach was used to identify possible post-flow tectonic subsidence on the Snake River Plain in Idaho.

High-Resolution Topomapping of Mars: Life After MER Site Selection

NASA Technical Reports Server (NTRS)

Kirk, R. L.; Howington-Kraus, E.; Hare, T. M.; Soricone, R.; Ross, K.; Weller, L.; Rosiek, M.; Redding, B.; Galuszka, D.; Haldemann, A. F. C.

2004-01-01

In this abstract we describe our ongoing use of high-resolution images from the Mars Global Surveyor Mars Orbiter Camera Narrow-Angle subsystem (MGS MOC-NA) to derive quantitative topographic and slope data for the martian surface at 3 - 10-m resolution. Our efforts over the past several years focused on assessment of candidate landing sites for the Mars Exploration Rovers (MER) and culminated in the selection of sites in Gusev crater and Meridiani Planum as safe as well as scientifically compelling. As of this writing, MER-A (Spirit) has landed safely in Gusev and we are performing a limited amount of additional mapping near the landing point to support localization of the lander and rover operations planning. The primary focus of our work, however, has been extending our techniques to sample a variety of geologic terrains planetwide to support both a variety of geoscientific studies and planning and data analysis for missions such as Mars Express, Mars Reconnaissance Orbiter, and Phoenix.

If Lava Mingled with Ground Ice on Mars

NASA Astrophysics Data System (ADS)

Martel, L. M. V.

2001-06-01

Clusters of small cones on the lava plains of Mars have caught the attention of planetary geologists for years for a simple and compelling reason: ground ice. These cones look like volcanic rootless cones found on Earth where hot lava flows over wet surfaces such as marshes, shallow lakes or shallow aquifers. Steam explosions fragment the lava into small pieces that fall into cone-shaped debris piles. Peter Lanagan, Alfred McEwen, Laszlo Keszthelyi (University of Arizona), and Thorvaldur Thordarson (University of Hawaii) recently identified groups of cones in the equatorial region of Mars using new high-resolution Mars Orbiter Camera (MOC) images. They report that the Martian cones have the same appearance, size, and geologic setting as rootless cones found in Iceland. If the Martian and terrestrial cones formed in the same way, then the Martian cones mark places where ground ice or groundwater existed at the time the lavas surged across the surface, estimated to be less than 10 million years ago, and where ground ice may still be today.

Ripples and Dunes

NASA Image and Video Library

2006-05-27

This MOC image shows dark sand dunes on the floor of an impact crater west of Hellas Planitia. Portions of the crater floor are exposed near the center and lower right corner of the image but, in general, the floor is covered by large, windblown ripples

Global Distribution of Dissected Duricrust on Mars

NASA Technical Reports Server (NTRS)

Mustard, J. F.; Cooper, C. D.

2000-01-01

Evidence for dissected duricrust was identified in high resolution MOC images. Analysis of all available images was used to map the global distribution of this terrain. It is apparently restricted to two latitude bands: 30-60 deg. N and 30-60 deg. S.

Melas Materials

NASA Image and Video Library

2006-05-01

This MOC image shows dark sand dunes superposed on layered, light-toned outcrops -- interpreted to be sedimentary rocks -- in Melas Chasma. Melas Chasma is part of the enormous Valles Marineris trough system

Moon/Mars Landing Commemorative Release: Gusev Crater and Ma'adim Vallis

NASA Technical Reports Server (NTRS)

1998-01-01

On July 20, 1969, the first human beings landed on the Moon. On July 20, 1976, the first robotic lander touched down on Mars. This July 20th-- 29 years after Apollo 11 and 22 years since the Viking 1 Mars landing-- we take a look forward toward one possible future exploration site on the red planet.

One of the advantages of the Mars Global Surveyor Mars Orbiter Camera (MOC) over its predecessors on the Viking and Mariner spacecraft is resolution. The ability to see-- resolve--fine details on the martian surface is key to planning future landing sites for robotic and, perhaps, human explorers that may one day visit the planet.

At present, NASA is studying potential landing sites for the Mars Surveyor landers, rovers, and sample return vehicles that are scheduled to be launched in 2001, 2003, and 2005. Among the types of sites being considered for these early 21st Century landings are those with 'exobiologic potential'--that is, locations on Mars that are in some way related to the past presence of water.

For more than a decade, two of the prime candidates suggested by various Mars research scientists are Gusev Crater and Ma'adim Vallis. Located in the martian southern cratered highlands at 14.7o S, 184.5o W, Gusev Crater is a large, ancient, meteor impact basin that--after it formed--was breached by Ma'adim Vallis.

Viking Orbiter observations provided some evidence to suggest that a fluid--most likely, water--once flowed through Ma'adim Vallis and into Gusev Crater. Some scientists have suggested that there were many episodes of flow into Gusev Crater (as well as flow out of Gusev through its topographically-lower northwestern rim). Some have also indicated that there were times when Ma'adim Vallis, also, was full of water such that it formed a long, narrow lake.

The possibility that water flowed into Gusev Crater and formed a lake has led to the suggestion that the materials seen on the floor of this crater--smooth-surfaced deposits, buried craters, and huge mesas near the mouth of Ma'adim Vallis--are composed of sediment that eroded out of the highlands to the south of Gusev Crater. In 1995, the Exobiology Program Office at NASA Headquarters produced a report, An Exobiological Strategy for Mars Exploration (NASA SP-530), that included Gusev Crater as a possible priority site for future Mars exploration because it might once have been a lake.

At 12:17 a.m. (PDT) on April 24, 1998-- during Mars Global Surveyor's 259th orbit--MOC obtained the high resolution image of Gusev Crater and Ma'adim Vallis shown above, in part to test some of the proposed hypotheses. The raw image has a scale of 7.3 meters (24 feet) per pixel. At this scale, there are no obvious shorelines that would indicate the past presence of a lake in either Ma'adim Vallis or Gusev Crater. There are several alternative explanations for this absence, including:

It is possible that any lake in Gusev occurred so long ago that erosion by wind and hillslope processes have long since removed such features.

It is possible that 7.3 meters per pixel is insufficient to identify key diagnostic lake features.

It is possible that a lake once existed, but that shore- and near-shore processes as they occur in terrestrial lake environments did not occur on Mars.

It is possible no lake ever existed.

When Mars Global Surveyor achieves its Mapping Orbit in March 1999, MOC will have the ability to obtain pictures with resolutions around 1.5 meters (5 feet) per pixel. Sometime during the mapping mission, it may be possible to image Gusev Crater again to look for potential lake features and possible future landing sites.

Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

Hot Dog and Butterfly, Nereidum Montes

NASA Technical Reports Server (NTRS)

1999-01-01

Some of the pictures returned from Mars by the Mars Orbiter Camera (MOC) onboard the Mars Global Surveyor (MGS) spacecraft show features that--at a glance--resemble familiar, non-geological objects on Earth. For example, the picture above at the left shows several low, relatively flat-topped hills (mesas) on the floor of a broad valley among the mountains of the Nereidum Montes region, northeast of Argyre Planitia. One of the mesas seen here looks like half of a butterfly (upper subframe on right). Another hill looks something like a snail or a hot dog wrapped and baked in a croissant roll (lower subframe on right). These mesas were formed by natural processes and are most likely the eroded remnants of a formerly more extensive layer of bedrock. In the frame on the left, illumination is from the upper left and the scene covers an area 2.7 km (1.7 miles) wide by 6.8 km (4.2 miles) high. The 'butterfly' is about 800 meters (875 yards) in length and the 'hot dog' is about 1 km (0.62 miles) long.

Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

Outer Dregs

NASA Image and Video Library

2006-05-15

This Mars MOC image shows the very edge of the south polar residual cap of Mars. The bright areas, which appear somewhat like pieces of sliced Swiss cheese, are composed mainly of frozen carbon dioxide

Aerodynamic

NASA Image and Video Library

2006-06-30

This MOC image shows dunes in the north polar region of Mars. In this springtime view, the dunes are largely covered by frozen carbon dioxide that was deposited during the winter months in the northern hemisphere

Candor Exposed

NASA Image and Video Library

2006-05-19

This MOC image shows outcrops of light-toned rock, interpreted to be sedimentary in origin, in east Candor Chasma. The exposures of light-toned rock are separated by areas of windblown ripples and dark sand

South Polar Autumn

NASA Image and Video Library

2006-04-22

This MOC image shows a portion of the south polar residual cap; darkened edges of the pits and mesas are evidence of the removal, by sublimation, of frozen carbon dioxide during the recent martian summer

CO2 Hourglass

NASA Image and Video Library

2006-04-24

This Mars MOC image shows a portion of the south polar residual cap of Mars. The bright, relatively homogeneous-appearing material extending from top north to bottom south is mainly composed of solid carbon dioxide

Syrian Volcano

NASA Image and Video Library

2006-07-23

This MOC image shows a small volcano in the Syria Planum region of Mars. Today, the lava flows that compose this small volcano are nearly hidden by a mantle of rough-textured, perhaps somewhat cemented, dust

Ganges Quagmire

NASA Image and Video Library

2006-09-27

This MOC image shows dark-toned, windblown sands and ripples, surrounding a light-toned hill, interpreted to be sedimentary rock, in Ganges Chasma. Ganges Chasma is part of the giant Valles Marineris trough system on Mars

A model for the catabolism of rhizopine in Rhizobium leguminosarum involves a ferredoxin oxygenase complex and the inositol degradative pathway.

PubMed

Bahar, M; de Majnik, J; Wexler, M; Fry, J; Poole, P S; Murphy, P J

1998-11-01

Rhizopines are nodule-specific compounds that confer an intraspecies competitive nodulation advantage to strains that can catabolize them. The rhizopine (3-O-methyl-scyllo-inosamine, 3-O-MSI) catabolic moc gene cluster mocCABRDE(F) in Rhizobium leguminosarum bv. viciae strain 1a is located on the Sym plasmid. MocCABR are homologous to the mocCABR gene products from Sinorhizobium meliloti. MocD and MocE contain motifs corresponding to a TOL-like oxygenase and a [2Fe-2S] Rieske-like ferredoxin, respectively. The mocF gene encodes a ferredoxin reductase that would complete the oxygenase system, but is not essential for rhizopine catabolism. We propose a rhizopine catabolic model whereby MocB transports rhizopine into the cell and MocDE and MocF (or a similar protein elsewhere in the genome), under the regulation of MocR, act in concert to form a ferredoxin oxygenase system that demethylates 3-O-MSI to form scyllo-inosamine (SI). MocA, an NAD(H)-dependent dehydrogenase, and MocC continue the catabolic process. Compounds formed then enter the inositol catabolic pathway.

Dark Polar Dunes

NASA Image and Video Library

2006-09-01

This MOC image shows dunes in the martian north polar region. The dunes are composed of dark, coarse sand. The white areas around the dunes are the last remaining areas of seasonal carbon dioxide frost cover

Wayward Travelers

NASA Image and Video Library

2006-02-24

This Mars Global Surveyor MOC image shows dark dunes superposed on the rippled floor of Proctor Crater in Noachis Terra. Winds blowing predominantly from east right to west left were responsible for the formation of these dunes

An Investigation of Dust Storms Observed with the Mars Color Imager

NASA Technical Reports Server (NTRS)

Guzewich, Scott D.; Toigo, Anthony D.; Wang, Huiqun

2017-01-01

Daily global imaging by the Mars Color Imager (MARCI) continues the record of the Mars Orbiter Camera (MOC) and has allowed creation of a long-duration record of Martian dust storms. We observe dust storms over the first two Mars years of the MARCI record, including tracking individual storms over multiple sols, as well as tracking the growth and recession of the seasonal polar caps. Using the combined 6 Mars year record of textured dust storms (storms with visible textures on the observed dust cloud tops), we study the relationship between textured dust storm activity and meteorology (as simulated by the MarsWRF general circulation model) and surface properties. We find that textured dust storms preferentially occur in places and seasons with above average surface wind stress. Textured dust storm occurrence also has a modest linear anti-correlation with surface albedo (0.43) and topography (0.40). Lastly, we perform an empirical orthogonal function (EOF) analysis on the distribution of occurrence of textured dust storms and find that over 50 of the variance in textured dust storm activity can be explained by two EOF modes. We associate the first EOF mode with cap-edge storms just before Ls = 180deg and the second EOF mode with flushing dust storms that occur from Ls = 180-210deg and again near Ls = 320deg.

Ti plasmid-encoded genes responsible for catabolism of the crown gall opine mannopine by Agrobacterium tumefaciens are homologs of the T-region genes responsible for synthesis of this opine by the plant tumor.

PubMed

Kim, K S; Farrand, S K

1996-06-01

Agrobacterium tumefaciens NT1 harboring pSaB4, which contains the 14-kb BamHI fragment 4 from the octopine/mannityl opine-type Ti plasmid pTi15955, grew well with agropine (AGR) but slowly with mannopine (MOP) as the sole carbon source. When a second plasmid encoding a dedicated transport system for MOP was introduced, these cells grew well with both AGR and MOP. Transposon insertion mutagenesis and subcloning identified a 5.7-kb region of BamHI fragment 4 that encodes functions required for the degradation of MOP. DNA sequence analysis revealed seven putative genes in this region: mocD (moc for mannityl opine catabolism) and mocE, oriented from right to left, and mocRCBAS, oriented from left to right. Significant identities exist at the nucleotide and derived amino acid sequence levels between these moc genes and the mas genes that are responsible for opine biosynthesis in crown gall tumors. MocD is a homolog of Mas2, the anabolic conjugase encoded by mas2'. MocE and MocC are related to the amino half and the carboxyl half, respectively, of Mas1 (MOP reductase), the second enzyme for MOP biosynthesis. These results indicate that the moc and mas genes evolved from a common origin. MocR and MocS are related to each other and to a putative repressor for the AGR degradation system encoded by the rhizogenic plasmid pRiA4. MocB and MocA are homologs of 6-phosphogluconate dehydratase and glucose-6-phosphate dehydrogenase, respectively. Mutations in mocD and mocE, but not mocC, are suppressed by functions encoded by the chromosome or the 450-kb megaplasmid present in many Agrobacterium isolates. We propose that moc genes derived from genes located elsewhere in the bacterial genome and that the tumor-expressed mas genes evolved from the bacterial moc genes.

Ti plasmid-encoded genes responsible for catabolism of the crown gall opine mannopine by Agrobacterium tumefaciens are homologs of the T-region genes responsible for synthesis of this opine by the plant tumor.

PubMed Central

Kim, K S; Farrand, S K

1996-01-01

Agrobacterium tumefaciens NT1 harboring pSaB4, which contains the 14-kb BamHI fragment 4 from the octopine/mannityl opine-type Ti plasmid pTi15955, grew well with agropine (AGR) but slowly with mannopine (MOP) as the sole carbon source. When a second plasmid encoding a dedicated transport system for MOP was introduced, these cells grew well with both AGR and MOP. Transposon insertion mutagenesis and subcloning identified a 5.7-kb region of BamHI fragment 4 that encodes functions required for the degradation of MOP. DNA sequence analysis revealed seven putative genes in this region: mocD (moc for mannityl opine catabolism) and mocE, oriented from right to left, and mocRCBAS, oriented from left to right. Significant identities exist at the nucleotide and derived amino acid sequence levels between these moc genes and the mas genes that are responsible for opine biosynthesis in crown gall tumors. MocD is a homolog of Mas2, the anabolic conjugase encoded by mas2'. MocE and MocC are related to the amino half and the carboxyl half, respectively, of Mas1 (MOP reductase), the second enzyme for MOP biosynthesis. These results indicate that the moc and mas genes evolved from a common origin. MocR and MocS are related to each other and to a putative repressor for the AGR degradation system encoded by the rhizogenic plasmid pRiA4. MocB and MocA are homologs of 6-phosphogluconate dehydratase and glucose-6-phosphate dehydrogenase, respectively. Mutations in mocD and mocE, but not mocC, are suppressed by functions encoded by the chromosome or the 450-kb megaplasmid present in many Agrobacterium isolates. We propose that moc genes derived from genes located elsewhere in the bacterial genome and that the tumor-expressed mas genes evolved from the bacterial moc genes. PMID:8655509

A Cost Analysis of the American Board of Internal Medicine's Maintenance-of-Certification Program.

PubMed

Sandhu, Alexander T; Dudley, R Adams; Kazi, Dhruv S

2015-09-15

In 2014, the American Board of Internal Medicine (ABIM) substantially increased the requirements and fees for its maintenance-of-certification (MOC) program. Faced with mounting criticism, the ABIM suspended certain content requirements in February 2015 but retained the increased fees and number of modules. An objective appraisal of the cost of MOC would help inform upcoming consultations about MOC reform. To estimate the total cost of the 2015 version of the MOC program ("2015 MOC") and the incremental cost relative to the 2013 version ("2013 MOC"). Decision analytic model. Published literature. All ABIM-certified U.S. physicians. 10 years (2015 to 2024). Societal. 2015 MOC. Testing costs (ABIM fees) and time costs (monetary value of physician time). Internists will incur an average of $23 607 (95% CI, $5380 to $66 383) in MOC costs over 10 years, ranging from $16 725 for general internists to $40 495 for hematologists-oncologists. Time costs account for 90% of MOC costs. Cumulatively, 2015 MOC will cost $5.7 billion over 10 years, $1.2 billion more than 2013 MOC. This includes $5.1 billion in time costs (resulting from 32.7 million physician-hours spent on MOC) and $561 million in testing costs. Costs are sensitive to time spent on MOC and MOC credits obtainable from current continuing education activities. Precise estimates of time required for MOC are not available. The ABIM MOC program will generate considerable costs, predominantly due to demands on physician time. A rigorous evaluation of its effect on clinical and economic outcomes is warranted to balance potential gains in health care quality and efficiency against the high costs identified in this study. University of California, San Francisco, and the U.S. Department of Veterans Affairs.

Flooded Place

NASA Image and Video Library

2006-07-26

This MOC image shows gullies a portion of a flood-carved canyon within the larger Kasei Valles system on Mars. This canyon is the result of the very last flood event that poured through the Kasei valleys, long ago

South Polar Designs

NASA Image and Video Library

2006-04-29

This MOC image shows an undulating scene in the south polar region of Mars. Small, elevated mesas of smooth, relatively homogeneous-appearing material are separated by low-lying regions that are speckled and darkened in some local areas

Polar Plumage

NASA Image and Video Library

2006-05-08

This Mars MOC image shows dunes in the north polar region of Mars covered by a layer of carbon dioxide frost that accumulated during the winter in 2005. Dark spots indicate areas where frost has begun to sublime away

Designer Troughs

NASA Image and Video Library

2006-06-11

This MOC image shows a wide, flat-floored trough flanked by several smaller, branching troughs in the Olympica Fossae region of Mars. Dark- and intermediate-toned slope streaks -- created by dry avalanches of dust -- occur on the trough walls

Aeolis Yardangs

NASA Image and Video Library

2006-01-12

This MGS MOC image shows a group of tapered ridges, known as yardangs, which formed by wind erosion of a relatively easily-eroded material, most likely sedimentary rock or volcanic ash deposits containing some fraction of sand-sized grains

Defrosting Polar Dunes--'The Snow Leopard'

NASA Technical Reports Server (NTRS)

1999-01-01

The patterns created by dark spots on defrosting south polar dunes are often strange and beautiful. This picture, which the Mars Orbiter Camera team has dubbed, 'the snow leopard,' shows a dune field located at 61.5oS, 18.9oW, as it appeared on July 1, 1999. The spots are areas where dark sand has been exposed from beneath bright frost as the south polar winter cap begins to retreat. Many of the spots have a diffuse, bright ring around them this is thought to be fresh frost that was re-precipitated after being removed from the dark spot. The spots seen on defrosting polar dunes are a new phenomenon that was not observed by previous spacecraft missions to Mars. Thus, there is much about these features that remains unknown. For example, no one yet knows why the dunes become defrosted by forming small spots that grow and grow over time. No one knows for sure if the bright rings around the dark spots are actually composed of re-precipitated frost. And no one knows for sure why some dune show spots that appear to be 'lined-up' (as they do in the picture shown here).

This Mars Global Surveyor Mars Orbiter Camera image is illuminated from the upper left. North is toward the upper right. The scale bar indicates a distance of 200 meters (656 feet).

Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

Polar Terminus

NASA Image and Video Library

2006-09-06

This MOC image shows the termination end of a group of layers in the north polar region of Mars, where they have been buried by younger, smoother-surfaced material. The layers are the banded features at the right/lower right

Diced Remnant

NASA Image and Video Library

2006-06-05

This MOC image shows blocky remnants of a material that was once more laterally extensive on the floor of an impact crater located northwest of Herschel Crater on Mars. Large ripples of windblown sediment have accumulated around and between the blocks

The dynamics of learning about a climate threshold

NASA Astrophysics Data System (ADS)

Keller, Klaus; McInerney, David

2008-02-01

Anthropogenic greenhouse gas emissions may trigger threshold responses of the climate system. One relevant example of such a potential threshold response is a shutdown of the North Atlantic meridional overturning circulation (MOC). Numerous studies have analyzed the problem of early MOC change detection (i.e., detection before the forcing has committed the system to a threshold response). Here we analyze the early MOC prediction problem. To this end, we virtually deploy an MOC observation system into a simple model that mimics potential future MOC responses and analyze the timing of confident detection and prediction. Our analysis suggests that a confident prediction of a potential threshold response can require century time scales, considerably longer that the time required for confident detection. The signal enabling early prediction of an approaching MOC threshold in our model study is associated with the rate at which the MOC intensity decreases for a given forcing. A faster MOC weakening implies a higher MOC sensitivity to forcing. An MOC sensitivity exceeding a critical level results in a threshold response. Determining whether an observed MOC trend in our model differs in a statistically significant way from an unforced scenario (the detection problem) imposes lower requirements on an observation system than the determination whether the MOC will shut down in the future (the prediction problem). As a result, the virtual observation systems designed in our model for early detection of MOC changes might well fail at the task of early and confident prediction. Transferring this conclusion to the real world requires a considerably refined MOC model, as well as a more complete consideration of relevant observational constraints.

Defrosting Polar Dunes--Dark Spots and Wind Streaks

NASA Technical Reports Server (NTRS)

1999-01-01

The first time that the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC)team saw dark spots on defrosting dune surfaces was in August and September of 1998. At that time, it was the north polar seasonal frost cap that was subliming away (more recent images from 1999 have shown the south polar frosts). This picture (above) shows a small portion of the giant dune field that surrounds the north polar region, as it appeared on August 23, 1998. At the time, it was early northern spring and the dunes were still covered with winter frost.

Dark spots had appeared on the north polar dunes, and many of them exhibited a radial or semi-radial pattern of dark streaks and streamers. At first, there was speculation that the streaks indicated that the defrosting process might somehow involve explosions! The dark spots seemed to resemble small craters with dark, radial ejecta. It seemed possible that frozen carbon dioxide trapped beneath water ice might somehow heat up, turn to gas, expand, and then 'explode' in either a small blast or at least a 'puff' of air similar to that which comes from the blowhole of a surfacing whale or seal.

The image shown here changed the earlier impression. The dark spots and streaks do not result from explosions. The spots--though not well understood--represent the earliest stages of defrosting on the sand dunes. The streaks, instead of being caused by small explosions, are instead the result of wind. In this picture, the fine, dark streaks show essentially identical orientations from spot to spot (e.g., compare the spots seen in boxes (a) and (b)). Each ray of dark material must result from wind blowing from a particular direction--for example, all of the spots in this picture exhibit a ray that points toward the upper left corner of the image, and each of these rays indicates the same wind regime. Each spot also has a ray pointing toward the lower right and top/upper-right. These, too, must indicate periods when the wind was strong enough to move materials, consistently, in only one direction.

The sand that makes up the north polar dunes is dark. Each spot and streak is composed of the dune sand. The bright surfaces are all covered with frost. This picture is located near 76.9oN, 271.2oW, in the north polar sand sea. Illumination is from the lower left. The 200 meter scale also indicates a distance of 656 feet.

Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

Filled Craters

NASA Image and Video Library

2006-05-11

This MOC image shows adjacent impact craters located north-northwest of the Acheron Fossae region of Mars. The two craters are of similar size and formed by meteor impacts. However, one is much more filled than the other, indicating that it is older

Striped Scarp

NASA Image and Video Library

2006-07-28

This MOC image shows a steep slope in the north polar region of Mars. The stripes indicate an exposure of layered material; the variations in brightness among the stripes are the result of varying amounts and textures on seasonal carbon dioxide frost

Frost-covered dunes

NASA Technical Reports Server (NTRS)

1999-01-01

MOC image of dunes in Chasma Boreale, a giant trough in the north polar cap. This September 1998 view shows dark sand emergent from beneath a veneer of bright frost left over from the northern winter that ended in July 1998.

Mars Global Digital Dune Database: MC2-MC29

USGS Publications Warehouse

Hayward, Rosalyn K.; Mullins, Kevin F.; Fenton, L.K.; Hare, T.M.; Titus, T.N.; Bourke, M.C.; Colaprete, Anthony; Christensen, P.R.

2007-01-01

Introduction The Mars Global Digital Dune Database presents data and describes the methodology used in creating the database. The database provides a comprehensive and quantitative view of the geographic distribution of moderate- to large-size dune fields from 65? N to 65? S latitude and encompasses ~ 550 dune fields. The database will be expanded to cover the entire planet in later versions. Although we have attempted to include all dune fields between 65? N and 65? S, some have likely been excluded for two reasons: 1) incomplete THEMIS IR (daytime) coverage may have caused us to exclude some moderate- to large-size dune fields or 2) resolution of THEMIS IR coverage (100m/pixel) certainly caused us to exclude smaller dune fields. The smallest dune fields in the database are ~ 1 km2 in area. While the moderate to large dune fields are likely to constitute the largest compilation of sediment on the planet, smaller stores of sediment of dunes are likely to be found elsewhere via higher resolution data. Thus, it should be noted that our database excludes all small dune fields and some moderate to large dune fields as well. Therefore the absence of mapped dune fields does not mean that such dune fields do not exist and is not intended to imply a lack of saltating sand in other areas. Where availability and quality of THEMIS visible (VIS) or Mars Orbiter Camera narrow angle (MOC NA) images allowed, we classifed dunes and included dune slipface measurements, which were derived from gross dune morphology and represent the prevailing wind direction at the last time of significant dune modification. For dunes located within craters, the azimuth from crater centroid to dune field centroid was calculated. Output from a general circulation model (GCM) is also included. In addition to polygons locating dune fields, the database includes over 1800 selected Thermal Emission Imaging System (THEMIS) infrared (IR), THEMIS visible (VIS) and Mars Orbiter Camera Narrow Angle (MOC NA) images that were used to build the database. The database is presented in a variety of formats. It is presented as a series of ArcReader projects which can be opened using the free ArcReader software. The latest version of ArcReader can be downloaded at http://www.esri.com/software/arcgis/arcreader/download.html. The database is also presented in ArcMap projects. The ArcMap projects allow fuller use of the data, but require ESRI ArcMap? software. Multiple projects were required to accommodate the large number of images needed. A fuller description of the projects can be found in the Dunes_ReadMe file and the ReadMe_GIS file in the Documentation folder. For users who prefer to create their own projects, the data is available in ESRI shapefile and geodatabase formats, as well as the open Geographic Markup Language (GML) format. A printable map of the dunes and craters in the database is available as a Portable Document Format (PDF) document. The map is also included as a JPEG file. ReadMe files are available in PDF and ASCII (.txt) files. Tables are available in both Excel (.xls) and ASCII formats.

Molecular and genetic characterization of the rhizopine catabolism (mocABRC) genes of Rhizobium meliloti L5-30.

PubMed

Rossbach, S; Kulpa, D A; Rossbach, U; de Bruijn, F J

1994-10-17

Rhizopine (L-3-O-methyl-scyllo-inosamine, 3-O-MSI) is a symbiosis-specific compound, which is synthesized in nitrogen-fixing nodules of Medicago sativa induced by Rhizobium meliloti strain L5-30. 3-O-MSI is thought to function as an unusual growth substrate for R. meliloti L5-30, which carries a locus (mos) responsible for its synthesis closely linked to a locus (moc) responsible for its degradation. Here, the essential moc genes were delimited by Tn5 mutagenesis and shown to be organized into two regions, separated by 3 kb of DNA. The DNA sequence of a 9-kb fragment spanning the two moc regions was determined, and four genes were identified that play an essential role in rhizopine catabolism (mocABC and mocR). The analysis of the DNA sequence and the amino acid sequence of the deduced protein products revealed that MocA resembles NADH-dependent dehydrogenases. MocB exhibits characteristic features of periplasmic-binding proteins that are components of high-affinity transport systems. MocC does not share significant homology with any protein in the database. MocR shows homology with the GntR class of bacterial regulator proteins. These results suggest that the mocABC genes are involved in the uptake and subsequent degradation of rhizopine, whereas mocR is likely to play a regulatory role.

Secrets of the Noachian Highlands: Pit Craters

NASA Technical Reports Server (NTRS)

2001-01-01

[figure removed for brevity, see original site] A) Context Image [figure removed for brevity, see original site] B) Gullies in M12-00595 [figure removed for brevity, see original site] C) Layers and gullies in M09-00539, M15-00964

Among the most exciting places that the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) has photographed during its three and a half years in orbit has been this crater in central Noachis Terra. Located at 47oS, 355oW, the crater appears to have been almost completely filled, and subsequently eroded in localized pits, by unknown processes. In this one place we see elements of the two most important results of the MOC investigation--the discovery of young gullies formed by fluid erosion and the occurrence of thick sequences of layered rock attesting to a martian past of substantial geologic activity.

Picture A shows the location of the other two figures, which are sections of three of about a dozen images acquired of this crater. Picture B (M12-00595) shows examples of gullies on the pit walls. Their contributary pattern (including the angles at which they join) argues for fluid behavior during their creation; the dark floors suggest that they have been active recently (or else they, like the slopes around them and most of Mars, would be lighter-toned owing to the accumulation of dust). These gullies are formed well down on the pit wall, where a distinctive, boulder-rich layer is found. Figure C, a mosaic of two high resolution images (M09-00539 and M15-00964), shows an area somewhat higher in the sequence of layered material that fills the crater. This sequence clearly alternates between layers that either contain or erode to form boulders and layers that do not have boulders. Note in particular the overhanging layers near the top center--such overhangs are evidence of the strength of the material. Here, too, gullies appear to start at specific layers; these, however, may not be as young as those seen in (B), as they appear to have at least a thin covering of dust. How it is that this crater came to be filled with layers of material containing (or eroding to create) boulders is a mystery.

Relationship Between Physicians' Active Participation in Maintenance of Certification and Patients' Perspective of Care Surveys.

PubMed

Morrell, Jessica; Stratman, Erik J

2016-06-01

Medical specialty boards have a Maintenance of Certification (MOC) paradigm whose intention is to ensure high-quality patient care. How the patient experience is affected by physician MOC enrollment/participation is unknown. Our goal was to determine if patient experience is associated with physician board certification and MOC status. We analyzed physician experience and MOC databases to determine the relationships among physicians' patient experience national percentile rankings and board certification status and MOC enrollment and activity status. Board-certified physicians enrolled in MOC did not have statistically significant different patient experience scores compared to board-certified physicians not enrolled in MOC. Mid-career physicians enrolled in MOC had patients more likely to recommend them and reported higher confidence in them. Patients did not perceive physicians participating in MOC patient safety modules as more cautious in providing patient care. Although most analyses did not demonstrate significant differences in patient experience scores for physicians actively participating in MOC compared to those not, some differences were noted. Higher provider-specific patient experience scores were noted, particularly for mid-career physicians.

Effects of different dietary inclusion levels of macadamia oil cake on growth performance and carcass characteristics in South African mutton merino lambs.

PubMed

Acheampong-Boateng, Owoahene; Bakare, Archibold G; Nkosi, Douglas B; Mbatha, Khanyisile R

2017-04-01

Growth performance and carcass characteristics of South African mutton merino fed graded levels of macadamia oil cake were assessed. A total of 60 South African mutton merino lambs were used in the experiment (initial live weight 25.0 ± 0.45 kg). Five diets with different inclusion levels of macadamia oil cake (MOC) were formulated: T1 (0% MOC, control), T2 (5% MOC), T3 (10% MOC), T4 (15% MOC) and T5 (20% MOC). Effects of inclusion level of MOC on average daily gain (ADG) and average daily feed intake (ADFI) were not significant (P > 0.05). Effects of inclusion levels of MOC on feed conversion ratio (FCR) of sheep were significant (P < 0.05). Highest proportion (71.2%) of sheep in the study had a carcass fat classification of 2, followed by a proportion of 17.3% sheep with a carcass fat classification of 3 and lastly 11.5% sheep had carcass fat classification of 4. Warm and cold carcass mass, chest circumference, carcass length and dressing percentage were higher in sheep fed on 5% MOC compared to other treatment diets (0, 10, 15 and 20% MOC) (P < 0.05). Fat rib eye had a greater area in sheep fed on 5% MOC (P < 0.05). It was concluded that 5% MOC provided the best results in terms of carcass characteristic measurements in sheep.

Exposed Ice in the Northern Mid-Latitudes of Mars

NASA Technical Reports Server (NTRS)

Allen, Carlton C.

2007-01-01

Ice-Rich Layer: Polygonal features with dimensions of approximately 100 meters, bounded by cracks, are commonly observed on the martian northern plains. These features are generally attributed to thermal cracking of ice-rich sediments, in direct analogy to polygons in terrestrial polar regions. We mapped polygons in the northern mid-latitudes (30 to 65 N) using MOC and HiRISE images. Polygons are scattered across the northern plains, with a particular concentration in western Utopia Planitia. This region largely overlaps the Late Amazonian Astapus Colles unit, characterized by polygonal terrain and nested pits consistent with periglacial and thermokarst origins. Bright and Dark Polygonal Cracks: An examination of all MOC images (1997 through 2003) covering the study area demonstrated that, at latitudes of 55 to 65 N, most of the imaged polygons show bright bounding cracks. We interpret these bright cracks as exposed ice. Between 40 and 55 N, most of the imaged polygons show dark bounding cracks. These are interpreted as polygons from which the exposed ice has been removed by sublimation. The long-term stability limit for exposed ice, even in deep cracks, apparently lies near 55 N. Bright and Dark Spots: Many HiRISE and MOC frames showing polygons in the northern plains also show small numbers of bright and dark spots, particularly in western Utopia Planitia. Many of the spots are closely associated with collapse features suggestive of thermokarst. The spots range from tens to approximately 100 meters in diameter. The bright spots are interpreted as exposed ice, due to their prevalence on terrain mapped as ice rich. The dark spots are interpreted as former bright spots, which have darkened as the exposed ice is lost by sublimation. The bright spots may be the martian equivalents of pingos, ice-cored mounds found in periglacial regions on Earth. Terrestrial pingos from which the ice core has melted often collapse to form depressions similar to the martian dark spots. Future Observations: The SHARAD radar should be able to confirm the presence and measure the depth of the interpreted ice-rich layer that forms the Astapus Colles unit. If this layer is confirmed it will strengthen the interpretation of bright polygon cracks and bright spots as exposed ice. HiRISE images of the northern plains are showing unprecedented details of the polygonal cracks. Future HiRISE images that include bright spots, compared to MOC images taken years earlier, will illustrate the temporal stability of the spots. The CRISM spectrometer, with multiple spectral bands and a spatial resolution around 20 meters, should allow mineralogical identification of the material exposed in the polygonal bounding cracks and in the bright spots.

Maintenance of Certification Part 4 Credit and recruitment for practice-based research.

PubMed

Gorzkowski, Julie A; Klein, Jonathan D; Harris, Donna L; Kaseeska, Kristen R; Whitmore Shaefer, Regina M; Bocian, Alison B; Davis, James B; Gotlieb, Edward M; Wasserman, Richard C

2014-10-01

Competing priorities in pediatric practice have created challenges for practice-based research. To increase recruitment success, researchers must design studies that provide added value to participants. This study evaluates recruitment of pediatricians into a study, before and after the development and addition of a quality improvement (QI) curriculum approved for American Board of Pediatrics Maintenance of Certification (MOC) Part 4 Credit as an enrollment incentive. Researchers implemented multiple outreach methods to enroll pediatric practices over 28 months. Field note review revealed that many physicians declined enrollment, stating that they prioritized MOC Part 4 projects over research studies. A QI curriculum meeting standards for MOC Part 4 Credit was developed and added to the study protocol as an enrollment incentive. Enrollment rates and characteristics of practitioners enrolled pre- and post-MOC were compared. Pre-MOC enrollment contributed 48% of practices in 22 months; post-MOC enrollment contributed 49% of practices in 6 months. An average of 3.5 practices enrolled per month pre-MOC, compared with 13.1 per month post-MOC (P < .001). Clinicians in pre- and post-MOC groups were similar in age, gender, race, and time spent on patient care; practices enrolled post-MOC were more likely to be located in federally designated Medically Underserved Areas than those enrolled pre-MOC (28.6% vs 12%, P = .03). Addition of MOC Part 4 Credit increased recruitment success and increased enrollment of pediatricians working in underserved areas. Including QI initiatives meeting MOC Part 4 criteria in practice-based research protocols may enhance participation and aid in recruiting diverse practice and patient populations. Copyright © 2014 by the American Academy of Pediatrics.

Highest-Resolution View of 'Face on Mars'

NASA Technical Reports Server (NTRS)

2001-01-01

A key aspect of the Mars Global Surveyor (MGS) Extended Mission is the opportunity to turn the spacecraft and point the Mars Orbiter Camera (MOC) at specific features of interest. A chance to point the spacecraft comes about ten times a week. Throughout the Primary Mission (March 1999 - January 2001), nearly all MGS operations were conducted with the spacecraft pointing 'nadir'--that is, straight down. In this orientation, opportunities to hit a specific small feature of interest were in some cases rare, and in other cases non-existent. In April 1998, nearly a year before MGS reached its Primary Mission mapping orbit, several tests of the spacecraft's ability to be pointed at specific features was conducted with great success (e.g., Mars Pathfinder landing site, Viking 1 site, and Cydonia landforms). When the Mars Polar Lander was lost in December 1999, this capability was again employed to search for the missing lander. Following the lander search activities, a plan to conduct similar off-nadir observations during the MGS Extended Mission was put into place. The Extended Mission began February 1, 2001. On April 8, 2001, the first opportunity since April 1998 arose to turn the spacecraft and point the MOC at the popular 'Face on Mars' feature.

Viking orbiter images acquired in 1976 showed that one of thousands of buttes, mesas, ridges, and knobs in the transition zone between the cratered uplands of western Arabia Terra and the low, northern plains of Mars looked somewhat like a human face. The feature was subsequently popularized as a potential 'alien artifact' in books, tabloids, radio talk shows, television, and even a major motion picture. Given the popularity of this landform, a new high-resolution view was targeted by pointing the spacecraft off-nadir on April 8, 2001. On that date at 20:54 UTC (8:54 p.m., Greenwich time zone), the MGS was rolled 24.8o to the left so that it was looking at the 'face' 165 km to the side from a distance of about 450 km. The resulting image has a resolution of about 2 meters (6.6 feet) per pixel. If present on Mars, objects the size of typical passenger jet airplanes would be distinguishable in an image of this scale. The large 'face' picture covers an area about 3.6 kilometers (2.2 miles) on a side. Sunlight illuminates the images from the left/lower left.

Mars at Ls 121°

NASA Image and Video Library

2006-10-02

These MOC images capture what Mars typically looks like in mid-afternoon at Ls 121°. In other words, with the exception of occasional differences in weather and polar frost patterns, this is what the red planet looks like this month October 2006

Auqakuh Stripe

NASA Image and Video Library

2006-06-01

This MOC image shows windblown ripples on the floor of Auqakuh Vallis. The light-toned area, running diagonally across the scene from the lower left to the upper right, may be dust that has accumulated in the bottom of the valley and on top of the ripples

Coregistration of high-resolution Mars orbital images

NASA Astrophysics Data System (ADS)

Sidiropoulos, Panagiotis; Muller, Jan-Peter

2015-04-01

The systematic orbital imaging of the Martian surface started 4 decades ago from NASA's Viking Orbiter 1 & 2 missions, which were launched in August 1975, and acquired orbital images of the planet between 1976 and 1980. The result of this reconnaissance was the first medium-resolution (i.e. ≤ 300m/pixel) global map of Mars, as well as a variety of high-resolution images (reaching up to 8m/pixel) of special regions of interest. Over the last two decades NASA has sent 3 more spacecraft with onboard instruments for high-resolution orbital imaging: Mars Global Surveyor (MGS) having onboard the Mars Orbital Camera - Narrow Angle (MOC-NA), Mars Odyssey having onboard the Thermal Emission Imaging System - Visual (THEMIS-VIS) and the Mars Reconnaissance Orbiter (MRO) having on board two distinct high-resolution cameras, Context Camera (CTX) and High-Resolution Imaging Science Experiment (HiRISE). Moreover, ESA has the multispectral High resolution Stereo Camera (HRSC) onboard ESA's Mars Express with resolution up to 12.5m since 2004. Overall, this set of cameras have acquired more than 400,000 high-resolution images, i.e. with resolution better than 100m and as fine as 25 cm/pixel. Notwithstanding the high spatial resolution of the available NASA orbital products, their accuracy of areo-referencing is often very poor. As a matter of fact, due to pointing inconsistencies, usually form errors in roll attitude, the acquired products may actually image areas tens of kilometers far away from the point that they are supposed to be looking at. On the other hand, since 2004, the ESA Mars Express has been acquiring stereo images through the High Resolution Stereo Camera (HRSC), with resolution that is usually 12.5-25 metres per pixel. The achieved coverage is more than 64% for images with resolution finer than 20 m/pixel, while for ~40% of Mars, Digital Terrain Models (DTMs) have been produced with are co-registered with MOLA [Gwinner et al., 2010]. The HRSC images and DTMs represent the best available 3D reference frame for Mars showing co-registration with MOLA<25m (loc.cit.). In our work, the reference generated by HRSC terrain corrected orthorectified images is used as a common reference frame to co-register all available high-resolution orbital NASA products into a common 3D coordinate system, thus allowing the examination of the changes that happen on the surface of Mars over time (such as seasonal flows [McEwen et al., 2011] or new impact craters [Byrne, et al., 2009]). In order to accomplish such a tedious manual task, we have developed an automatic co-registration pipeline that produces orthorectified versions of the NASA images in realistic time (i.e. from ~15 minutes to 10 hours per image depending on size). In the first step of this pipeline, tie-points are extracted from the target NASA image and the reference HRSC image or image mosaic. Subsequently, the HRSC areo-reference information is used to transform the HRSC tie-points pixel coordinates into 3D "world" coordinates. This way, a correspondence between the pixel coordinates of the target NASA image and the 3D "world" coordinates is established for each tie-point. This set of correspondences is used to estimate a non-rigid, 3D to 2D transformation model, which transforms the target image into the HRSC reference coordinate system. Finally, correlation of the transformed target image and the HRSC image is employed to fine-tune the orthorectification results, thus generating results with sub-pixel accuracy. This method, which has been proven to be accurate, robust to resolution differences and reliable when dealing with partially degraded data and fast, will be presented, along with some example co-registration results that have been achieved by using it. Acknowledgements: The research leading to these results has received partial funding from the STFC "MSSL Consolidated Grant" ST/K000977/1 and partial support from the European Union's Seventh Framework Programme (FP7/2007-2013) under iMars grant agreement n° 607379. References: [1] K. F. Gwinner, et al. (2010) Topography of Mars from global mapping by HRSC high-resolution digital terrain models and orthoimages: characteristics and performance. Earth and Planetary Science Letters 294, 506-519, doi:10.1016/j.epsl.2009.11.007. [2] A. McEwen, et al. (2011) Seasonal flows on warm martian slopes. Science , 333 (6043): 740-743. [3] S. Byrne, et al. (2009) Distribution of mid-latitude ground ice on mars from new impact craters. Science, 325(5948):1674-1676.

Return to "Giant's Footprint" 3 Decades After Mariner 7 Flyby

NASA Image and Video Library

2000-04-24

As we head into the 21st Century, it seems hard to believe that human beings have been sending spacecraft toward Mars for more than 3 decades already. The first spacecraft to reach Mars was Mariner 4 in 1965. This success was followed by two spacecraft in 1969, Mariners 6 and 7. Now the wonders and alien beauty of Mars continue to unfold with each day that the Mars Global Surveyor -- which arrived in September 1997 -- continues to radio its data to Earth. Mars exploration was always difficult and each bit of data returned from the planet is a marvel. On August 5, 1969, the Mariner 7 spacecraft flew past Mars at a minimum altitude of about 4200 km. It acquired 14 wide/narrow angle image pairs during the few minutes of the "near encounter" flyby. One of these image pairs, 7N19/7N20, shows the south polar region and contains a feature that at the time was nicknamed "the Giant's Footprint." Shown in the first two pictures, above, the feature consists of two adjoining craters, one about 80 km (50 mi) in diameter and the other about 50 km (31 mi) across near latitude 76°S, longitude 276°W. The oblique geometry of the Mariner 7 image enhances the impression of a footprint. The "Giant's Footprint" was almost missed when Mariner 7 suffered a near-catastrophic battery failure just a few days before the encounter -- on July 30 -- that put the spacecraft sporadically out of contact with Earth for two days. Ground controllers at the Jet Propulsion Laboratory (JPL)recovered the spacecraft, re-planned its imaging sequence based on results from the Mariner 6 flyby on July 31, and salvaged all of the mission's science goals in under a week! In the 1970's, the larger crater in "giant's footprint" was named "Vishniac" in honor of Wolf Vishniac, an American microbiologist of the University of Rochester who was instrumental in the development of methods to search for life on Mars. Vishniac was tragically killed in a fall in Antarctica in 1973 while retrieving a life detection experiment, and the crater was named in honor of this "giant" in the search for life on Mars. More than three decades after the Mariner 7 flyby, Mars Global Surveyor's Mars Orbiter Camera (MOC) acquired a commemorative view of the interior of Vishniac Crater on October 25, 1999. The context image and the 3-meters (9.8 feet)-per-pixel narrow angle view are shown above (in the lower image pair). Mariner 7's 7N20 has a nominal resolution of about 180 meters (591 feet) per pixel, while the MOC high resolution view is about 60 times higher (in actuality, the lower quality of the Mariner 7 images makes the resolution gain even more dramatic). The MOC high resolution view (lower right, above) shows a 1.5 kilometer-(0.9 mile)-wide portion of the floor of Vishniac in the process of defrosting during southern spring. The bright areas are still frost-covered, while the darker areas are either defrosted or composed of darkened or "dirty" frost. The dark patches in the image seem to serve as sources for dark streaks of material that has either been blown across the landscape by wind, or has somehow caused the erosion of frost to create the streaks. Dark streaks follow the local topography, as might the wind that blew across this landscape. This pattern of spots and streaks was quite common on the defrosting south polar cap during the spring that lasted from early August 1999 to late December 1999. All images shown here are illuminated by sunlight from the lower right. Image orientation with north toward the bottom was selected in order to show the "footprint" visible in Mariner 7 image 7N20. The Mariner 7 images were recovered at Malin Space Science Systems from the original 7-track magnetic tapes, archived on CD-ROM by the JPL Data Preservation activity. More images relating to the release can be viewed at http://photojournal.jpl.nasa.gov/catalog/PIA02365

Albedo Study of the Depositional Fans Associated with Martian Gullies

NASA Astrophysics Data System (ADS)

Craig, J.; Sears, D. W. G.

2005-03-01

This work is a two-part investigation of the albedo of the depositional aprons or fans associated with Martian gully features. Using Adobe Systems Photoshop 5.0 software we analyzed numerous Mars Global Surveyor MOC and Mars Odyssey THEMIS images.

Martian Dust Devils: 2 Mars Years of MGS MOC Observations

NASA Astrophysics Data System (ADS)

Cantor, B. A.; Edgett, K. S.

2002-12-01

Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) wide and narrow angle images have captured more than 1000 active dust devils over 2 Mars years. In the most recent Mars year, we repeatedly imaged (and are continuing to image) several areas to monitor dust devil occurrence. Some Mars dust devils are as small as a few to 10s of meters across, others are 100s of meters across and over 6 km high. Each Martian hemisphere has a "dust devil season" that generally follows the subsolar latitude. An exception is NW Amazonis, which has frequent, large dust devils throughout northern spring and summer (probably every afternoon; observations are acquired 2-3 times a week). The Amazonis and other MOC observations show no evidence that dust devils cause, lead to, or have a systematic relationship with dust storms. However, dust devils sometimes do occur near small, localized storms; and one specific relation occurred during the onset of the global dust events of 2001: slightly elevated levels of atmospheric dust (an optically thin cloud) triggered a very short period of dust devil activity in NW Amazonis in early northern autumn. The redistribution of dust by the 2001 global events may have also affected subsequent spring and summer dust devil activity in Hellas, where considerably fewer dust devils occurred in 2001-2002 than 1999-2000. In SW Syria, frequent, large dust devils occurred after the 2001 global events and persisted through southern summer. While dust devils have no specific relation to dust storms, they might play a role in the seasonal "wave of darkening" at middle and high latitudes by removing or disrupting thin veneers of dust. Dust devils have been observed to create thin, filamentary streaks. Some streaks are darker than their surroundings, while others are lighter. Some dust devils do not create streaks. At mid-latitudes, surfaces darken in spring as 100s of crisscrossing streaks form on widely-varied terrain. Some rare streaks exhibit cycloidal patterns similar to those created on Earth by tornadoes with multiple sub-vortices. The streaks occur at nearly all latitudes and elevations, from north polar dunes to the south polar layered terrain, from the summit of Olympus Mons to the floor of Hellas. During "dust devil season" at a given latitude, tremendous changes in streak patterns occur in periods as short as 1 month. These observations, along with repeated imaging in NW Amazonis and SW Syria, provide some idea of the frequency of dust devils. Uncertain is whether dust devils are responsible for all thin, filamentary streaks: while active vortices have been seen creating the plethora of streaks at southern mid-latitudes, none have been observed on the northern plains, despite observation of similar streak patterns. Perhaps northern plains dust devils occur at a different time of day relative to the MGS 1400 LT orbit, or perhaps dust devils did not form them. We monitored removal of dust from surfaces after the 2001 global dust events in several locations. Of particular interest was western Syrtis Major, which had brightened considerably after the 2001 storms. We observed this area for several months while very little change occurred. Finally, in January 2002, the surface was swept clean of most of its 2001 veneer of dust in a period of about 1 week. Dust devils played no role in this process; instead, regional surface winds were responsible.

Getting maintenance of certification to work: a grounded theory study of physicians' perceptions.

PubMed

Cook, David A; Holmboe, Eric S; Sorensen, Kristi J; Berger, Richard A; Wilkinson, John M

2015-01-01

Despite general support for the goals of maintenance of certification (MOC), concerns have been raised about its effectiveness, relevance, and value. To identify barriers and enabling features associated with MOC and how MOC can be changed to better accomplish its intended purposes. Grounded theory focus group study of 50 board-certified primary care and subspecialist internal medicine and family medicine physicians in an academic medical center and outlying community sites. Eleven focus groups. Constant comparative method to analyze transcripts and identify themes related to MOC perceptions and purposes and to construct a model to guide improvement. Participants identified misalignments between the espoused purposes of MOC (eg, to promote high-quality care, commitment to the profession, lifelong learning, and the science of quality improvement) and MOC as currently implemented. At present, MOC is perceived by physicians as an inefficient and logistically difficult activity for learning or assessment, often irrelevant to practice, and of little benefit to physicians, patients, or society. To resolve these misalignments, we propose a model that invites increased support from organizations, effectiveness and relevance of learning activities, value to physicians, integration with clinical practice, and coherence across MOC tasks. Physicians view MOC as an unnecessarily complex process that is misaligned with its purposes. Acknowledging and correcting these misalignments will help MOC meet physicians' needs and improve patient care.

The American Board of Radiology Maintenance of Certification (MOC) Program in Radiologic Physics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Thomas, Stephen R.; Hendee, William R.; Paliwal, Bhudatt R.

2005-01-01

Maintenance of Certification (MOC) recognizes that in addition to medical knowledge, several essential elements involved in delivering quality care must be developed and maintained throughout one's career. The MOC process is designed to facilitate and document the professional development of each diplomate of The American Board of Radiology (ABR) through its focus on the essential elements of quality care in Diagnostic Radiology and its subspecialties, and in the specialties of Radiation Oncology and Radiologic Physics. The initial elements of the ABR-MOC have been developed in accord with guidelines of The American Board of Medical Specialties. All diplomates with a ten-year,more » time-limited primary certificate in Diagnostic Radiologic Physics, Therapeutic Radiologic Physics, or Medical Nuclear Physics who wish to maintain certification must successfully complete the requirements of the appropriate ABR-MOC program for their specialty. Holders of multiple certificates must meet ABR-MOC requirements specific to the certificates held. Diplomates with lifelong certificates are not required to participate in the MOC, but are strongly encouraged to do so. MOC is based on documentation of individual participation in the four components of MOC: (1) professional standing, (2) lifelong learning and self-assessment, (3) cognitive expertise, and (4) performance in practice. Within these components, MOC addresses six competencies: medical knowledge, patient care, interpersonal and communication skills, professionalism, practice-based learning and improvement, and systems-based practice.« less

Volcanoes Ceraunius Tholus and Uranius Tholus

NASA Technical Reports Server (NTRS)

2002-01-01

Acquired in March 2002, this Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) wide angle view shows the martian volcanoes, Ceraunius Tholus (lower) and Uranius Tholus (upper). The presence of impact craters on these volcanoes, particularly on Uranius Tholus; indicates that they are quite ancient and are not active today. The light-toned area on the southeastern face (toward lower right) of Ceraunius Tholus is a remnant of a once more extensive deposit of dust from the global dust storm events that occurred in 2001. The crater at the summit of Ceraunius Tholus is about 25 km (15.5 mi) across. Sunlight illuminates the scene from the lower left.

Mars at Ls 53°: Acidalia/Mare Erythraeum

NASA Image and Video Library

2006-05-09

This picture is a composite of MOC daily global images acquired at Ls 53° during a previous Mars year. This month, Mars looks similar, as Ls 53° occurs in mid-May 2006. The picture shows the Acidalia/Mare Erythraeum face of Mars

Automated detection of Martian water ice clouds: the Valles Marineris

NASA Astrophysics Data System (ADS)

Ogohara, Kazunori; Munetomo, Takafumi; Hatanaka, Yuji; Okumura, Susumu

2016-10-01

We need to extract water ice clouds from the large number of Mars images in order to reveal spatial and temporal variations of water ice cloud occurrence and to meteorologically understand climatology of water ice clouds. However, visible images observed by Mars orbiters for several years are too many to visually inspect each of them even though the inspection was limited to one region. Therefore, an automated detection algorithm of Martian water ice clouds is necessary for collecting ice cloud images efficiently. In addition, it may visualize new aspects of spatial and temporal variations of water ice clouds that we have never been aware. We present a method for automatically evaluating the presence of Martian water ice clouds using difference images and cross-correlation distributions calculated from blue band images of the Valles Marineris obtained by the Mars Orbiter Camera onboard the Mars Global Surveyor (MGS/MOC). We derived one subtracted image and one cross-correlation distribution from two reflectance images. The difference between the maximum and the average, variance, kurtosis, and skewness of the subtracted image were calculated. Those of the cross-correlation distribution were also calculated. These eight statistics were used as feature vectors for training Support Vector Machine, and its generalization ability was tested using 10-fold cross-validation. F-measure and accuracy tended to be approximately 0.8 if the maximum in the normalized reflectance and the difference of the maximum and the average in the cross-correlation were chosen as features. In the process of the development of the detection algorithm, we found many cases where the Valles Marineris became clearly brighter than adjacent areas in the blue band. It is at present unclear whether the bright Valles Marineris means the occurrence of water ice clouds inside the Valles Marineris or not. Therefore, subtracted images showing the bright Valles Marineris were excluded from the detection of water ice clouds

Climate, soil texture, and soil types affect the contributions of fine-fraction-stabilized carbon to total soil organic carbon in different land uses across China.

PubMed

Cai, Andong; Feng, Wenting; Zhang, Wenju; Xu, Minggang

2016-05-01

Mineral-associated organic carbon (MOC), that is stabilized by fine soil particles (i.e., silt plus clay, <53 μm), is important for soil organic carbon (SOC) persistence and sequestration, due to its large contribution to total SOC (TSOC) and long turnover time. Our objectives were to investigate how climate, soil type, soil texture, and agricultural managements affect MOC contributions to TSOC in China. We created a dataset from 103 published papers, including 1106 data points pairing MOC and TSOC across three major land use types: cropland, grassland, and forest. Overall, the MOC/TSOC ratio ranged from 0.27 to 0.80 and varied significantly among soil groups in cropland, grassland, and forest. Croplands and forest exhibited significantly higher median MOC/TSOC ratios than in grassland. Moreover, forest and grassland soils in temperate regions had higher MOC/TSOC ratios than in subtropical regions. Furthermore, the MOC/TSOC ratio was much higher in ultisol, compared with the other soil types. Both the MOC content and MOC/TSOC ratio were positively correlated with the amount of fine fraction (silt plus clay) in soil, highlighting the importance of soil texture in stabilizing organic carbon across various climate zones. In cropland, different fertilization practices and land uses (e.g., upland, paddy, and upland-paddy rotation) significantly altered MOC/TSOC ratios, but not in cropping systems (e.g., mono- and double-cropping) characterized by climatic differences. This study demonstrates that the MOC/TSOC ratio is mainly driven by soil texture, soil types, and related climate and land uses, and thus the variations in MOC/TSOC ratios should be taken into account when quantitatively estimating soil C sequestration potential of silt plus clay particles on a large scale. Copyright © 2016 Elsevier Ltd. All rights reserved.

The Diversity of Martian Volcanic features as Seen in the MOC, THEMIS, and MOM Data Sets

NASA Technical Reports Server (NTRS)

Mouginis-Mark, Peter J.

2005-01-01

This one-year project (which included one-year no-cost tension) focused on the evolution of the summit areas of Martian volcanoes. It extended the studies conducted under an earlier MDAP project (Grant NAG5-9576, Principal Investigator P. Mouginis- Mark). By using data collected from the Mars Orbiter Camera (MOC), Thermal Emission Imaging System (THEMIS), and the Mars Orbiter Laser Altimeter (MOLA) instruments, we tried to better understand the diversity of constructional volcanism on Mars, and hence further understand the eruption processes. By inspecting THEMIS and MOC data, we explored the following four questions: (1) Where might near-surface volatiles have been released at the summits of the Tharsis volcanoes? Is the trapping and subsequent remobilization of degassed volatiles [Scott and Wilson, 19991 adequate to produce eruptions responsible for extensive deposits such as the ones identified on Arsia Mons [Mouginis-Mark, 2002]? To answer this question, we investigated the diversity of eruption styles by studying the summit areas of Arsia, Pavonis and Ascraeus Montes. (2) What are the geomorphic characteristics of the valley system on Hecates Tholus, a volcano that we have previously proposed experienced explosive activity [Mouginis-Murk et al., 1982]? Our inspection of THEMIS data suggests that water release on the volcano took place over an extended period of time, suggesting that hydrothermal activity may have taken place here. (3) How similar are the collapse processes observed at Martian and terrestrial calderas? New THEMIS data provide a more complete view of the entire Olympus Mons caldera, thereby enabling the comparison with the collapse features at Masaya volcano, Nicaragua, to be investigated. (4) What can we learn about the emplacement of long lava flows in the lava plains of Eastern Tharsis? The result of this work provided a greater understanding of the temporal and spatial variations in the eruptive history of volcanoes on Mars, and the influence of the volatiles within the top few kilometers of the volcanic edifice. This relationship in turn pertains to the availability of volatiles (both juvenile magmatic volatiles and ground water contained within the near-surface rocks) and to magma supply rates at appreciable distances (tens to hundreds of kilometers) from the centers of volcanoes. Explosive volcanism on Mars, a major factor in the release of water at the surface, may have been driven not only by volatiles within the parental melt, but also by magma encountering water or ice at shallow depth within the volcano [Mouginis-Mark et al., 1982, 1988; Crown and Greeley, 1993; Robinson et al., 19931.

75 FR 80101 - Self-Regulatory Organizations; New York Stock Exchange LLC; Notice of Filing and Immediate...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-12-21

... entry, cancellation of such orders and the calculation and publication of imbalances. In particular... a Mandatory MOC/LOC Imbalance Publication. The rule therefore suggests that members or member... all MOC/LOC orders that would join the same side of a published MOC/LOC imbalance and the entry of MOC...

Expanding Educators' Contributions to Continuous Quality Improvement of American Board of Medical Specialties Maintenance of Certification.

PubMed

Nora, Lois Margaret; Pouwels, Mellie Villahermosa; Irons, Mira

2016-01-01

The American Board of Medical Specialties board certification has transformed into a career-long process of learning, assessment, and performance improvement through its Program for Maintenance of Certification (MOC). Medical educators across many medical professional organizations, specialty societies, and other institutions have played important roles in shaping MOC and tailoring its overarching framework to the needs of different specialties. This Commentary addresses potential barriers to engagement in work related to MOC for medical school (MS) and academic health center (AHC) educators and identifies reasons for, and ways to accomplish, greater involvement in this work. The authors present ways that medical and other health professions educators in these settings can contribute to the continuous improvement of the MOC program including developing educational and assessment activities, engaging in debate about MOC, linking MOC with institutional quality improvement activities, and pursuing MOC-related scholarship. MS- and AHC-based educators have much to offer this still-young and continually improving program, and their engagement is sought, necessary, and welcomed.

Star PolyMOCs with Diverse Structures, Dynamics, and Functions by Three-Component Assembly

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Yufeng; Gu, Yuwei; Keeler, Eric G.

2016-12-05

We report star polymer metal–organic cage (polyMOC) materials whose structures, mechanical properties, functionalities, and dynamics can all be precisely tailored through a simple three-component assembly strategy. The star polyMOC network is composed of tetra-arm star polymers functionalized with ligands on the chain ends, small molecule ligands, and palladium ions; polyMOCs are formed via metal–ligand coordination and thermal annealing. The ratio of small molecule ligands to polymer-bound ligands determines the connectivity of the MOC junctions and the network structure. The use of large M12L24 MOCs enables great flexibility in tuning this ratio, which provides access to a rich spectrum of materialmore » properties including tunable moduli and relaxation dynamics.« less

Kinematics Mapping and Monitoring of ''Swiss Cheese'' Features in the Polar Icy Regions Over Two Martian Years Base on HIRISE-MOC (NASA) Images

NASA Astrophysics Data System (ADS)

Aftabi, P.

2016-06-01

The mapping and monitoring of ''swiss cheese'' feature example of this paper achieved by pixel markers measurements pro-posed by author. This monoring suggest high amount of displacements in pits of Martian polar areas.

Mars global digital dune database and initial science results

USGS Publications Warehouse

Hayward, R.K.; Mullins, K.F.; Fenton, L.K.; Hare, T.M.; Titus, T.N.; Bourke, M.C.; Colaprete, A.; Christensen, P.R.

2007-01-01

A new Mars Global Digital Dune Database (MGD3) constructed using Thermal Emission Imaging System (THEMIS) infrared (IR) images provides a comprehensive and quantitative view of the geographic distribution of moderate- to large-size dune fields (area >1 kM2) that will help researchers to understand global climatic and sedimentary processes that have shaped the surface of Mars. MGD3 extends from 65??N to 65??S latitude and includes ???550 dune fields, covering ???70,000 km2, with an estimated total volume of ???3,600 km3. This area, when combined with polar dune estimates, suggests moderate- to large-size dune field coverage on Mars may total ???800,000 km2, ???6 times less than the total areal estimate of ???5,000,000 km2 for terrestrial dunes. Where availability and quality of THEMIS visible (VIS) or Mars Orbiter Camera. narrow-angle (MOC NA) images allow, we classify dunes and include dune slipface measurements, which are derived from gross dune morphology and represent the prevailing wind direction at the last time of significant dune modification. For dunes located within craters, the azimuth from crater centroid to dune field centroid (referred to as dune centroid azimuth) is calculated and can provide an accurate method for tracking dune migration within smooth-floored craters. These indicators of wind direction are compared to output from a general circulation model (GCM). Dune centroid azimuth values generally correlate to regional wind patterns. Slipface orientations are less well correlated, suggesting that local topographic effects may play a larger role in dune orientation than regional winds. Copyright 2007 by the American Geophysical Union.

Candidate Landing Site for the Mars Science Laboratory: Vernal Crater, S.W. ARabia Terra

NASA Technical Reports Server (NTRS)

Paris, K. N.; Allen, C. C.; Oehler, D. Z.

2007-01-01

In the fall of 2009, the Mars Science Laboratory (MSL) will be launched to Mars. The purpose of this mission is to assess biologic potential and geology and to investigate planetary processes of relevance to past habitability. MSL will be able to provide visual, chemical, radiation, and environmental data with its suite of instruments [1]. In order to be selected for the MSL landing site, certain engineering requirements must be met [1] and the area should contain geologic features suggestive of past habitability, so that the overriding science goal of the mission will be attained. There are a total of 33 proposed landing sites as of the first MSL Landing Site Workshop held in Pasadena, CA from May 31st to June 2nd, 2006 [1]. There will be an opportunity to gather high resolution visual and hyperspectral data on all proposed landing sites from the now-orbiting Mars Reconnaissance Orbiter (MRO) which entered martian orbit and began its main science phase in November of 2006 [2]. The data being gathered are from: the high resolution imaging science experiment (HiRISE), the context (CTX) camera and the compact reconnaissance imaging spectrometer (CRISM) onboard the spacecraft. The footprints of these instruments are centered on a single point, and each proposer must submit these coordinates, along with the coordinates of the proposed landing ellipse. Data from these instruments, along with new MOC images and THEMIS mosaics, will be used to enhance our understanding of the geologic and engineering parameters of each site.

Volcanism and Fluvio-Glacial Processes on the Interior Layered Deposits of Valles Marineris, Mars?

NASA Astrophysics Data System (ADS)

Chapman, M. G.

2005-12-01

The Interior Layered Deposits (ILDs) in Valles Marineris have been suggested to be possible sub-ice volcanoes. Recent images also show evidence of possible fluvio-glacial processes on the ILDs and hence volcano/ice/water interaction. For example, Mars Express Mission anaglyph from Orbit 334 of central Ophir and Candor Chasmata, THEMIS image V10551002, and MOC images E1700142 and E190020 show 2 ILD mounds in central Candor Chasma that have been sheared off at approximately equal elevations by some material that has been subsequently removed. Level shearing of ILD rock materials and subsequent removal of the abrasive material, suggest ice erosion and glacial processes because glacial ice is mobile enough to grind the rock and can melt away. Another adjacent ILD mound in Central Candor shows an abrupt flank termination and damming of material, rather than flank scour. The dammed material appears to be layers piled up in a ridge at the ILD base. This relation is observed on the HRSC anaglyph and MOC images E0101343 and E201146. Another ILD in Melas Chasma, seen on MOC image M0804981, shows lobes of flank material that terminate along a lineation; possibly suggesting lobe confinement against subsequently removed material. This morphology can also be observed on the flank of the Gangis Chasma ILD in MOC image M0705587. A possible terrestrial volcanic analog for this ILD flank morphology is the Helgafell hyaloclasitic ridge (tindar) in Iceland (Chapman et al., 2004), the eastern flank of which has a linear termination interpreted as largely unmodified and caused by hyalotuff material banked against a former ice wall that has since melted away (Schopka et al., 2003). Glacial shearing of some ILDs and confined banking of other ILDs suggest that these mounds formed at different times, as the sheared ILD likely predated ice and the confined ILD may have formed concurrently with ice. Alternatively, the banking may have been due to lack of shear forces (static ice) and confined post-depositional avalanche deposits. However, exposed in the banked cliff faces are near horizontal bedding planes that can be traced upslope into angled flank layers; a relation that may suggest ice concurrent with volcanic ILD formation (Chapman and Smellie, in press). In addition to glacial processes, many Mars ILDs show fluvial gullies cut into mostly low lying flank deposits. Gullies are eroded into all sides of the ILDs including their north-facing slopes, so solar heating likely did not generate the gullies. Although formal work on the subject is lacking, ongoing terrestrial observation by the author (on an edifice north of Helgafell and in Gjalp eruption films) indicate fluvial erosion of subglacial volcanoes on Earth may be concurrent with their formation, occurring after edifices rise above their surrounding ice-confined meltwater lake. Remnant ice on the top of the edifices can melt to generate streams that erode the growing volcanic flanks.

Annotated type catalogue of the Chrysididae (Insecta, Hymenoptera) deposited in the collection of Radoszkowski in the Polish Academy of Sciences, Kraków

PubMed Central

Rosa, Paolo; Wiśniowski, Bogdan; Xu, Zai-fu

2015-01-01

Abstract A critical and annotated catalogue of 183 types of Hymenoptera Chrysididae belonging to 124 taxa housed in the Radoszkowski collection is given. Radoszkowski type material from other institutes has also been checked. Six lectotypes are designated in Kraków (ISEA-PAN): Chrysis acceptabilis Radoszkowski, 1891; Chrysis persica Radoczkowsky, 1881; Chrysis daphnis Mocsáry, 1889; Chrysis lagodechii Radoszkowski, 1889; Chrysis remota Mocsáry, 1889 and Chrysis vagans Radoszkowski, 1877. The lectotype of Brugmoia pellucida Radoszkowski, 1877 is designated in Moscow (MMU). Four new combinations are proposed: Philoctetes araraticus (Radoszkowski, 1890), comb. n.; Pseudomalus hypocrita (du Buysson, 1893), comb. n.; Chrysis eldari (Radoszkowski, 1893), comb. n.; and Chrysura mlokosewitzi (Radoszkowski, 1889), comb. n.. Ten new synonyms are given: Chrysis auropunctata Mocsáry, 1889, syn. n. of Chrysis angolensis Radoszkovsky, 1881; Chrysis chrysochlora Mocsáry, 1889, syn. n. and Chrysis viridans Radoszkowski, 1891, syn. n. of Chrysis keriensis Radoszkowski, 1887; Chrysis angustifrons var. ignicollis Trautmann, 1926, syn. n. of Chrysis eldari (Radoszkowski, 1893); Chrysis maracandensis var. simulatrix Radoszkowski, 1891, syn. n. of Chrysis maracandensis Radoszkowski, 1877; Chrysis pulchra Radoszkovsky, 1880, syn. n. of Spinolia dallatorreana (Mocsáry, 1896); Chrysis rubricollis du Buysson, 1900, syn. n. of Chrysis eldari (Radoszkowski, 1893); Chrysis subcoerulea Radoszkowski, 1891, syn. n. of Chrysis chlorochrysa Mocsáry, 1889; Chrysis therates Mocsáry, 1889, syn. n. of Chrysis principalis Smith, 1874; and Notozus komarowi Radoszkowski, 1893, syn. n. of Elampus obesus (Mocsáry, 1890). One species is revaluated: Chrysis chalcochrysa Mocsáry, 1887. Chrysis kizilkumiana Rosa is the new name for Chrysis uljanini Radoszkowski & Mocsáry, 1889 nec Radoszkowski, 1877. Pictures of seventy-seven type specimens are given. PMID:25829848

Quantifying colocalization by correlation: the Pearson correlation coefficient is superior to the Mander's overlap coefficient.

PubMed

Adler, Jeremy; Parmryd, Ingela

2010-08-01

The Pearson correlation coefficient (PCC) and the Mander's overlap coefficient (MOC) are used to quantify the degree of colocalization between fluorophores. The MOC was introduced to overcome perceived problems with the PCC. The two coefficients are mathematically similar, differing in the use of either the absolute intensities (MOC) or of the deviation from the mean (PCC). A range of correlated datasets, which extend to the limits of the PCC, only evoked a limited response from the MOC. The PCC is unaffected by changes to the offset while the MOC increases when the offset is positive. Both coefficients are independent of gain. The MOC is a confusing hybrid measurement, that combines correlation with a heavily weighted form of co-occurrence, favors high intensity combinations, downplays combinations in which either or both intensities are low and ignores blank pixels. The PCC only measures correlation. A surprising finding was that the addition of a second uncorrelated population can substantially increase the measured correlation, demonstrating the importance of excluding background pixels. Overall, since the MOC is unresponsive to substantial changes in the data and is hard to interpret, it is neither an alternative to nor a useful substitute for the PCC. The MOC is not suitable for making measurements of colocalization either by correlation or co-occurrence.

Use of Dynamic Models and Operational Architecture to Solve Complex Navy Challenges

NASA Technical Reports Server (NTRS)

Grande, Darby; Black, J. Todd; Freeman, Jared; Sorber, TIm; Serfaty, Daniel

2010-01-01

The United States Navy established 8 Maritime Operations Centers (MOC) to enhance the command and control of forces at the operational level of warfare. Each MOC is a headquarters manned by qualified joint operational-level staffs, and enabled by globally interoperable C41 systems. To assess and refine MOC staffing, equipment, and schedules, a dynamic software model was developed. The model leverages pre-existing operational process architecture, joint military task lists that define activities and their precedence relations, as well as Navy documents that specify manning and roles per activity. The software model serves as a "computational wind-tunnel" in which to test a MOC on a mission, and to refine its structure, staffing, processes, and schedules. More generally, the model supports resource allocation decisions concerning Doctrine, Organization, Training, Material, Leadership, Personnel and Facilities (DOTMLPF) at MOCs around the world. A rapid prototype effort efficiently produced this software in less than five months, using an integrated process team consisting of MOC military and civilian staff, modeling experts, and software developers. The work reported here was conducted for Commander, United States Fleet Forces Command in Norfolk, Virginia, code N5-0LW (Operational Level of War) that facilitates the identification, consolidation, and prioritization of MOC capabilities requirements, and implementation and delivery of MOC solutions.

Return to 'Giant's Footprint' 3 Decades After Mariner 7 Flyby

NASA Technical Reports Server (NTRS)

2000-01-01

[figure removed for brevity, see original site] Click for full-resolution image.

[figure removed for brevity, see original site] Click for full-resolution image.

[figure removed for brevity, see original site] Click for full-resolution image.

[figure removed for brevity, see original site] Click for full-resolution image.

As we head into the 21st Century, it seems hard to believe that human beings have been sending spacecraft toward Mars for more than 3 decades already. The first spacecraft to reach Mars was Mariner 4 in 1965. This success was followed by two spacecraft in 1969, Mariners 6 and 7. Now the wonders and alien beauty of Mars continue to unfold with each day that the Mars Global Surveyor--which arrived in September 1997--continues to radio its data to Earth.

Mars exploration was always difficult and each bit of data returned from the planet is a marvel. On August 5, 1969, the Mariner 7 spacecraft flew past Mars at a minimum altitude of about 4200 km. It acquired 14 wide/narrow angle image pairs during the few minutes of the 'near encounter' flyby. One of these image pairs, 7N19/7N20, shows the south polar region and contains a feature that at the time was nicknamed 'the Giant's Footprint.' Shown in the first two pictures, above, the feature consists of two adjoining craters, one about 80 km (50 mi) in diameter and the other about 50 km (31 mi) across near latitude 76oS, longitude 276oW. The oblique geometry of the Mariner 7 image enhances the impression of a footprint.

The 'Giant's Footprint' was almost missed when Mariner 7 suffered a near-catastrophic battery failure just a few days before the encounter--on July 30--that put the spacecraft sporadically out of contact with Earth for two days. Ground controllers at the Jet Propulsion Laboratory (JPL)recovered the spacecraft, re-planned its imaging sequence based on results from the Mariner 6 flyby on July 31, and salvaged all of the mission's science goals in under a week!

In the 1970's, the larger crater in 'giant's footprint' was named 'Vishniac' in honor of Wolf Vishniac, an American microbiologist of the University of Rochester who was instrumental in the development of methods to search for life on Mars. Vishniac was tragically killed in a fall in Antarctica in 1973 while retrieving a life detection experiment, and the crater was named in honor of this 'giant' in the search for life on Mars.

More than three decades after the Mariner 7 flyby, Mars Global Surveyor's Mars Orbiter Camera (MOC) acquired a commemorative view of the interior of Vishniac Crater on October 25, 1999. The context image and the 3-meters (9.8 feet)-per-pixel narrow angle view are shown above (in the lower image pair). Mariner 7's 7N20 has a nominal resolution of about 180 meters (591 feet) per pixel, while the MOC high resolution view is about 60 times higher (in actuality, the lower quality of the Mariner 7 images makes the resolution gain even more dramatic).

The MOC high resolution view (lower right, above) shows a 1.5 kilometer-(0.9 mile)-wide portion of the floor of Vishniac in the process of defrosting during southern spring. The bright areas are still frost-covered, while the darker areas are either defrosted or composed of darkened or 'dirty' frost. The dark patches in the image seem to serve as sources for dark streaks of material that has either been blown across the landscape by wind, or has somehow caused the erosion of frost to create the streaks. Dark streaks follow the local topography, as might the wind that blew across this landscape. This pattern of spots and streaks was quite common on the defrosting south polar cap during the spring that lasted from early August 1999 to late December 1999.

All images shown here are illuminated by sunlight from the lower right. Image orientation with north toward the bottom was selected in order to show the 'footprint' visible in Mariner 7 image 7N20. The Mariner 7 images were recovered at Malin Space Science Systems from the original 7-track magnetic tapes, archived on CD-ROM by the JPL Data Preservation activity.

Coagulation mechanism of salt solution-extracted active component in Moringa oleifera seeds.

PubMed

Okuda, T; Baes, A U; Nishijima, W; Okada, M

2001-03-01

This study focuses on the coagulation mechanism by the purified coagulant solution (MOC-SC-PC) with the coagulation active component extracted from M. oleifera seeds using salt solution. The addition of MOC-SC-PC tap water formed insoluble matters. This formation was responsible for kaolin coagulation. On the other hand, insoluble matters were not formed when the MOC-SC-PC was added into distilled water. The formation was affected by Ca2+ or other bivalent cations which may connect each molecule of the active coagulation component in MOC-SC-PC and form a net-like structure. The coagulation mechanism of MOC-SC-PC seemed to be an enmeshment of Kaolin by the insoluble matters with the net-like structure. In case of Ca2+ ion (bivalent cations), at least 0.2 mM was necessary for coagulation at 0.3 mgC l-1 dose of MOC-SC-PC. Other coagulation mechanisms like compression of double layer, interparticle bridging or charge neutralization were not responsible for the coagulation by MOC-SC-PC.

The dependence of the oceans MOC on mesoscale eddy diffusivities: A model study

NASA Technical Reports Server (NTRS)

Marshall, John; Scott, Jeffery R.; Romanou, Anastasia; Kelley, Maxwell; Leboissetier, Anthony

2017-01-01

The dependence of the depth and strength of the ocean's global meridional overturning cells (MOC) on the specification of mesoscale eddy diffusivity (K) is explored in two ocean models. The GISS and MIT ocean models are driven by the same prescribed forcing fields, configured in similar ways, spun up to equilibrium for a range of K 's and the resulting MOCs mapped and documented. Scaling laws implicit in modern theories of the MOC are used to rationalize the results. In all calculations the K used in the computation of eddy-induced circulation and that used in the representation of eddy stirring along neutral surfaces, is set to the same value but is changed across experiments. We are able to connect changes in the strength and depth of the Atlantic MOC, the southern ocean upwelling MOC, and the deep cell emanating from Antarctica, to changes in K.

Practical Applications for Maintenance of Certification Products in Child and Adolescent Residency Training.

PubMed

Williams, Laurel L; Sexson, Sandra; Dingle, Arden D; Young-Walker, Laine; John, Nadyah; Hunt, Jeffrey

2016-04-01

The authors evaluated whether Maintenance of Certification (MOC) Performance-in-Practice products in training increases trainee knowledge of MOC processes and is viewed by trainees as a useful activity. Six child and adolescent psychiatry fellowships used MOC products in continuity clinics to assess their usefulness as training tools. Two surveys assessed initial knowledge of MOC and usefulness of the activity. Forty-one fellows completed the initial survey. A majority of first-year fellows indicated lack of awareness of MOC in contrast to a majority of second-year fellows who indicated some awareness. Thirty-five fellows completed the second survey. A majority of first- and second-year fellows found the activity easy to execute and would change something about their practice as a result. Using MOC products in training appears to be a useful activity that may assist training programs in teaching the principles of self- and peer-learning.

Martian Dust Cycle

NASA Astrophysics Data System (ADS)

Cantor, B. A.; James, P. B.

The Mars Observer Camera (MOC), aboard Mars Global Surveyor (MGS), has completed approximately 3 consecutive Martian years of global monitoring, since entering its mapping orbit on March 9, 1999. MOC observations have shown the important role that dust devils and dust storms play in the Martian dust cycle on time scales ranging from semi-diurnally to interannually. These dust events have been observed across much of the planet from the depths of Hellas basin to the summit of Arsia Mons and range in size from10s of meters across (dust devils) to planet encircling (global dust veils). Though dust devils occur throughout most of the Martian year, each hemisphere has a "dust devil season" that generally follows the subsolar latitude and appears to be repeatable from year-to-year. An exception is NW Amazonis, which has frequent, large dust devils throughout northern spring and summer. MOC observations show no evidence that dust devils cause or lead to dust storms, however, observations do suggest that dust storms can initiate dust devil activity. Dust devils also might play a role in maintaining the low background dust opacity of the Martian atmosphere. Dust storms occur almost daily with few exceptions, with 1000s occurring each year in the present Martian environment, dispelling the notion of a "Classical Dust Storm Season". However, there does appear to be an annual dust storm cycle, with storms developing in specific locations during certain seasons and that some individual storm events are repeatable from year-to-year. The majority of storms develop near the receding seasonal polar cap edge or along the corresponding polar hood boundaries in their respective hemispheres, but they also occur in the northern plains, the windward side of the large shield volcanoes, and in low laying regions such as Hellas, Argyre, and Chryse. The rarest of dust events are the "Great Storms" or "Global Events", of which only 6 (4 "planet encircling" and 2 "global") have been observed to date. With MOC we have observed that global dust events are not individual storms but are composed of a number of local and regional storms (sources) and that they do not signify climatic changes, but are only short-term perturbations to the general interannually repeatable Martian dust storm cycle.

Frequency tuning of medial-olivocochlear-efferent acoustic reflexes in humans as functions of probe frequency

PubMed Central

Lilaonitkul, Watjana

2012-01-01

The medial-olivocochlear (MOC) acoustic reflex is thought to provide frequency-specific feedback that adjusts the gain of cochlear amplification, but little is known about how frequency specific the reflex actually is. We measured human MOC tuning through changes in stimulus frequency otoacoustic emissions (SFOAEs) from 40-dB-SPL tones at probe frequencies (fps) near 0.5, 1.0, and 4.0 kHz. MOC activity was elicited by 60-dB-SPL ipsilateral, contralateral, or bilateral tones or half-octave noise bands, with elicitor frequency (fe) varied in half-octave steps. Tone and noise elicitors produced similar results. At all probe frequencies, SFOAE changes were produced by a wide range of elicitor frequencies with elicitor frequencies near 0.7–2.0 kHz being particularly effective. MOC-induced changes in SFOAE magnitude and SFOAE phase were surprisingly different functions of fe: magnitude inhibition largest for fe close to fp, phase change largest for fe remote from fp. The metric ΔSFOAE, which combines both magnitude and phase changes, provided the best match to reported (cat) MOC neural inhibition. Ipsilateral and contralateral MOC reflexes often showed dramatic differences in plots of MOC effect vs. elicitor frequency, indicating that the contralateral reflex does not give an accurate picture of ipsilateral-reflex properties. These differences in MOC effects appear to imply that ipsilateral and contralateral reflexes have different actions in the cochlea. The implication of these results for MOC function, cochlear mechanics, and the production of SFOAEs are discussed. PMID:22190630

A Tale of 3 Craters

NASA Technical Reports Server (NTRS)

2004-01-01

11 November 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image captures some of the complexity of the martian upper crust. Mars does not simply have an impact-cratered surface, it's upper crust is a cratered volume. Over time, older craters on Mars have been eroded, filled, buried, and in some cases exhumed and re-exposed at the martian surface. The crust of Mars is layered to depths of 10 or more kilometers, and mixed in with the layered bedrock are a variety of ancient craters with diameters ranging from a few tens of meters (a few tens of yards) to several hundred kilometers (more than one or two hundred miles).

The picture shown here captures some of the essence of the layered, cratered volume of the upper crust of Mars in a very simple form. The image shows three distinct circular features. The smallest, in the lower right quarter of the image, is a meteor crater surrounded by a mound of material. This small crater formed within a layer of bedrock that once covered the entire scene, but today is found only in this small remnant adjacent to the crater. The intermediate-sized crater, west (left) of the small one, formed either in the next layer down--that is, below the layer in which the small crater formed--or it formed in some layers that are now removed, but was big enough to penetrate deeply into the rock that is near the surface today. The largest circular feature in the image, in the upper right quarter of the image, is still largely buried. It formed in layers of rock that are below the present surface. Erosion has brought traces of its rim back to the surface of Mars. This picture is located near 50.0oS, 77.8oW, and covers an area approximately 3 km (1.9 mi) across. Sunlight illuminates this October 2004 image from the upper left.

Simultaneous measurement of noise-activated middle-ear muscle reflex and stimulus frequency otoacoustic emissions.

PubMed

Goodman, Shawn S; Keefe, Douglas H

2006-06-01

Otoacoustic emissions serve as a noninvasive probe of the medial olivocochlear (MOC) reflex. Stimulus frequency otoacoustic emissions (SFOAEs) elicited by a low-level probe tone may be the optimal type of emission for studying MOC effects because at low levels, the probe itself does not elicit the MOC reflex [Guinan et al. (2003) J. Assoc. Res. Otolaryngol. 4:521]. Based on anatomical considerations, the MOC reflex activated by ipsilateral acoustic stimulation (mediated by the crossed olivocochlear bundle) is predicted to be stronger than the reflex to contralateral stimulation. Broadband noise is an effective activator of the MOC reflex; however, it is also an effective activator of the middle-ear muscle (MEM) reflex, which can make results difficult to interpret. The MEM reflex may be activated at lower levels than measured clinically, and most previous human studies have not explicitly included measurements to rule out MEM reflex contamination. The current study addressed these issues using a higher-frequency SFOAE probe tone to test for cochlear changes mediated by the MOC reflex, while simultaneously monitoring the MEM reflex using a low-frequency probe tone. Broadband notched noise was presented ipsilaterally at various levels to elicit probe-tone shifts. Measurements are reported for 15 normal-hearing subjects. With the higher-frequency probe near 1.5 kHz, only 20% of subjects showed shifts consistent with an MOC reflex in the absence of an MEM-induced shift. With the higher-frequency probe near 3.5 kHz, up to 40% of subjects showed shifts in the absence of an MEM-induced shift. However, these responses had longer time courses than expected for MOC-induced shifts, and may have been dominated by other cochlear processes, rather than MOC reflex. These results suggest caution in the interpretation of effects observed using ipsilaterally presented acoustic activators intended to excite the MOC reflex.

Aquifers In Nirgal Vallis

NASA Astrophysics Data System (ADS)

Reiss, D.; Jaumann, R.

The topographic information provided by the Mars Orbiter Laser Altimeter has been used in combination with the Mars Observer Camera imagery to estimate the topo- graphic position of sapping pits and gully heads on the rim of Nirgal Vallis. Hence Nirgal Vallis is understood to be formed by groundwater sapping (1, 2, 3, 4) an aquifer is proposed as water supply. Gullies in the northern rim of Nirgal Vallis as discovered in Mars Observer Camera (MOC) images (5, 6) proof the existence of such an aquifer. Further evidence for sapping in Nirgal Vallis is demonstrated by short hanging tribu- taries with amphitheater-like heads. The basis of these sapping pits defines the con- tact of aquifer to aquiclude during the valley formation. The gully heads are much deeper under the local surface and the correlation of their topographic position with the valley depth indicate the subsidence of the groundwater level following the ver- tical erosion of the valley. This implies the existence of different groundwater tables over time confined by impermeable layers, whereas the gully head level is the most recent groundwater table which still may be erosional active under the conditions of increasing water pressure and ice barrier failure (5). The occurrence of more than one tilted sapping level at different topographic positions which are time-correlated with the erosional notching of the valley, either indicates different aquifers with litholog- ical aquicludes or a climate controlled subsidence of the permafrost layer acting as confining layer. References: (1) Baker et al., 1992, In: Mars, Univ. of Arizona Press. (2) Carr, 1995, JGR 100, 7479. (3) Malin and Carr, 1999, Icarus, 397, 589. (4) Jaumann and Reiss, 2002, LPSC. (5) Malin and Edgett, 2000, Science, 288, 2330. (6) Malin and Edgett, 2001, JGR 106, 23429.

Comparative genomics of pyridoxal 5′-phosphate-dependent transcription factor regulons in Bacteria

PubMed Central

Suvorova, Inna A.

2016-01-01

The MocR-subfamily transcription factors (MocR-TFs) characterized by the GntR-family DNA-binding domain and aminotransferase-like sensory domain are broadly distributed among certain lineages of Bacteria. Characterized MocR-TFs bind pyridoxal 5′-phosphate (PLP) and control transcription of genes involved in PLP, gamma aminobutyric acid (GABA) and taurine metabolism via binding specific DNA operator sites. To identify putative target genes and DNA binding motifs of MocR-TFs, we performed comparative genomics analysis of over 250 bacterial genomes. The reconstructed regulons for 825 MocR-TFs comprise structural genes from over 200 protein families involved in diverse biological processes. Using the genome context and metabolic subsystem analysis we tentatively assigned functional roles for 38 out of 86 orthologous groups of studied regulators. Most of these MocR-TF regulons are involved in PLP metabolism, as well as utilization of GABA, taurine and ectoine. The remaining studied MocR-TF regulators presumably control genes encoding enzymes involved in reduction/oxidation processes, various transporters and PLP-dependent enzymes, for example aminotransferases. Predicted DNA binding motifs of MocR-TFs are generally similar in each orthologous group and are characterized by two to four repeated sequences. Identified motifs were classified according to their structures. Motifs with direct and/or inverted repeat symmetry constitute the majority of inferred DNA motifs, suggesting preferable TF dimerization in head-to-tail or head-to-head configuration. The obtained genomic collection of in silico reconstructed MocR-TF motifs and regulons in Bacteria provides a basis for future experimental characterization of molecular mechanisms for various regulators in this family. PMID:28348826

Massively parallel sequencing analysis of mucinous ovarian carcinomas: genomic profiling and differential diagnoses.

PubMed

Mueller, Jennifer J; Schlappe, Brooke A; Kumar, Rahul; Olvera, Narciso; Dao, Fanny; Abu-Rustum, Nadeem; Aghajanian, Carol; DeLair, Deborah; Hussein, Yaser R; Soslow, Robert A; Levine, Douglas A; Weigelt, Britta

2018-05-21

Mucinous ovarian cancer (MOC) is a rare type of epithelial ovarian cancer resistant to standard chemotherapy regimens. We sought to characterize the repertoire of somatic mutations in MOCs and to define the contribution of massively parallel sequencing to the classification of tumors diagnosed as primary MOCs. Following gynecologic pathology and chart review, DNA samples obtained from primary MOCs and matched normal tissues/blood were subjected to whole-exome (n = 9) or massively parallel sequencing targeting 341 cancer genes (n = 15). Immunohistochemical analysis of estrogen receptor, progesterone receptor, PTEN, ARID1A/BAF250a, and the DNA mismatch (MMR) proteins MSH6 and PMS2 was performed for all cases. Mutational frequencies of MOCs were compared to those of high-grade serous ovarian cancers (HGSOCs) and mucinous tumors from other sites. MOCs were heterogeneous at the genetic level, frequently harboring TP53 (75%) mutations, KRAS (71%) mutations and/or CDKN2A/B homozygous deletions/mutations (33%). Although established criteria for diagnosis were employed, four cases harbored mutational and immunohistochemical profiles similar to those of endometrioid carcinomas, and one case for colorectal or endometrioid carcinoma. Significant differences in the frequencies of KRAS, TP53, CDKN2A, FBXW7, PIK3CA and/or APC mutations between the confirmed primary MOCs (n = 19) and HGSOCs, mucinous gastric and/or mucinous colorectal carcinomas were found, whereas no differences in the 341 genes studied between MOCs and mucinous pancreatic carcinomas were identified. Our findings suggest that the assessment of mutations affecting TP53, KRAS, PIK3CA, ARID1A and POLE, and DNA MMR protein expression may be used to further aid the diagnosis and treatment decision-making of primary MOC. Copyright © 2018 Elsevier Inc. All rights reserved.

Effects of Southern Hemisphere Wind Changes on the Meridional Overturning Circulation in Ocean Models.

PubMed

Gent, Peter R

2016-01-01

Observations show that the Southern Hemisphere zonal wind stress maximum has increased significantly over the past 30 years. Eddy-resolving ocean models show that the resulting increase in the Southern Ocean mean flow meridional overturning circulation (MOC) is partially compensated by an increase in the eddy MOC. This effect can be reproduced in the non-eddy-resolving ocean component of a climate model, providing the eddy parameterization coefficient is variable and not a constant. If the coefficient is a constant, then the Southern Ocean mean MOC change is balanced by an unrealistically large change in the Atlantic Ocean MOC. Southern Ocean eddy compensation means that Southern Hemisphere winds cannot be the dominant mechanism driving midlatitude North Atlantic MOC variability.

Evidence for Recent Liquid Water on Mars: Gullies at 70oS in Polar Pit Walls

NASA Technical Reports Server (NTRS)

2000-01-01

[figure removed for brevity, see original site]

Gully landforms proposed to have been caused by geologically-recent seepage and runoff of liquid water on Mars are found in the most unlikely places. They typically occur in areas that are quite cold--well below freezing--all year round. Like the old adage about moss on trees, nearly all of them form on slopes that face away from sunlight. Most of the gullies occur at latitudes between 30o and 70o.

The highest latitude at which martian gullies have been found is around 70o-75oS on the walls of pits developed in the south polar pitted plains. If you were at this same latitude on Earth, you would be in Antarctica. This region spends much of the winter--which lasts approximately 6 months on Mars--in darkness and at temperatures cold enough to freeze carbon dioxide (around -130oC or -200oF). Nevertheless, gullies with very sharp, deep, v-shaped channels are seen on the pit walls (above, left).

Based upon the locations of the tops of the channels on the slope shown here, the inferred site of liquid seepage is located at a layer in the pit wall about 1/3 of the way down from the top of the MOC image. The channels start wide and taper downslope. The area above the channels is layered and has been eroded by mass movement--dry avalanching of debris--to form a pattern of chutes and ridges on the upper slope of the pit wall. The top layer appears to have many boulders in it (each about the size of a small house), these boulders are left behind on the upper slopes of the pit wall as debris is removed.

Centered near 70.7oS, 355.7oW, the MOC image was acquired July 14, 1999, and covers an area approximately 2.8 km (1.7 mi) wide by 2.1 km (1.3 mi) high. Sunlight illuminates the MOC image from the upper left and north is toward the upper left. The context view (right) is from the Viking 2 orbiter and was acquired in 1977. The Viking picture is illuminated from the top/upper left; north is toward the upper right. The small white box in the context frame (upper right corner) shows the location of the high resolution MOC view.

Evidence for Recent Liquid Water on Mars: Channeled Aprons in a Small Crater within Newton Crater

NASA Technical Reports Server (NTRS)

2000-01-01

[figure removed for brevity, see original site]

Newton Crater is a large basin formed by an asteroid impact that probably occurred more than 3 billion years ago. It is approximately 287 kilometers (178 miles) across. The picture shown here (top) highlights the north wall of a specific, smaller crater located in the southwestern quarter of Newton Crater (above). The crater of interest was also formed by an impact; it is about 7 km (4.4 mi) across, which is about 7 times bigger than the famous Meteor Crater in northern Arizona in North America.

The north wall of the small crater has many narrow gullies eroded into it. These are hypothesized to have been formed by flowing water and debris flows. Debris transported with the water created lobed and finger-like deposits at the base of the crater wall where it intersects the floor (bottom center top image). Many of the finger-like deposits have small channels indicating that a liquid--most likely water--flowed in these areas. Hundreds of individual water and debris flow events might have occurred to create the scene shown here. Each outburst of water from higher upon the crater slopes would have constituted a competition between evaporation, freezing, and gravity.

The individual deposits at the ends of channels in this MOC image mosaic were used to get a rough estimate of the minimum amount of water that might be involved in each flow event. This is done first by assuming that the deposits are like debris flows on Earth. In a debris flow, no less than about 10% (and no more than 30%) of their volume is water. Second, the volume of an apron deposit is estimated by measuring the area covered in the MOC image and multiplying it by a conservative estimate of thickness, 2 meters (6.5 feet). For a flow containing only 10% water, these estimates conservatively suggest that about 2.5 million liters (660,000 gallons) of water are involved in each event; this is enough to fill about 7 community-sized swimming pools or enough to supply 20 people with their water needs for a year.

The MOC high resolution view is located near 41.1oS, 159.8oW and is a mosaic of three different pictures acquired between January and May 2000. The MOC scene is illuminated from the left; north is up. The context picture was acquired in 1977 by the Viking 1 orbiter and is illuminated from the upper right.

Recording and labeling at a site along the cochlea shows alignment of medial olivocochlear and auditory nerve tonotopic mappings

PubMed Central

2016-01-01

Medial olivocochlear (MOC) neurons provide an efferent innervation to outer hair cells (OHCs) of the cochlea, but their tonotopic mapping is incompletely known. In the present study of anesthetized guinea pigs, the MOC mapping was investigated using in vivo, extracellular recording, and labeling at a site along the cochlear course of the axons. The MOC axons enter the cochlea at its base and spiral apically, successively turning out to innervate OHCs according to their characteristic frequencies (CFs). Recordings made at a site in the cochlear basal turn yielded a distribution of MOC CFs with an upper limit, or “edge,” due to usually absent higher-CF axons that presumably innervate more basal locations. The CFs at the edge, normalized across preparations, were equal to the CFs of the auditory nerve fibers (ANFs) at the recording sites (near 16 kHz). Corresponding anatomical data from extracellular injections showed spiraling MOC axons giving rise to an edge of labeling at the position of a narrow band of labeled ANFs. Overall, the edges of the MOC CFs and labeling, with their correspondences to ANFs, suggest similar tonotopic mappings of these efferent and afferent fibers, at least in the cochlear basal turn. They also suggest that MOC axons miss much of the position of the more basally located cochlear amplifier appropriate for their CF; instead, the MOC innervation may be optimized for protection from damage by acoustic overstimulation. PMID:26823515

Recording and labeling at a site along the cochlea shows alignment of medial olivocochlear and auditory nerve tonotopic mappings.

PubMed

Brown, M Christian

2016-03-01

Medial olivocochlear (MOC) neurons provide an efferent innervation to outer hair cells (OHCs) of the cochlea, but their tonotopic mapping is incompletely known. In the present study of anesthetized guinea pigs, the MOC mapping was investigated using in vivo, extracellular recording, and labeling at a site along the cochlear course of the axons. The MOC axons enter the cochlea at its base and spiral apically, successively turning out to innervate OHCs according to their characteristic frequencies (CFs). Recordings made at a site in the cochlear basal turn yielded a distribution of MOC CFs with an upper limit, or "edge," due to usually absent higher-CF axons that presumably innervate more basal locations. The CFs at the edge, normalized across preparations, were equal to the CFs of the auditory nerve fibers (ANFs) at the recording sites (near 16 kHz). Corresponding anatomical data from extracellular injections showed spiraling MOC axons giving rise to an edge of labeling at the position of a narrow band of labeled ANFs. Overall, the edges of the MOC CFs and labeling, with their correspondences to ANFs, suggest similar tonotopic mappings of these efferent and afferent fibers, at least in the cochlear basal turn. They also suggest that MOC axons miss much of the position of the more basally located cochlear amplifier appropriate for their CF; instead, the MOC innervation may be optimized for protection from damage by acoustic overstimulation. Copyright © 2016 the American Physiological Society.

Inverted Martian Craters in Lineated Glacial Valleys, Ismenius Lacus Region, Mars

NASA Technical Reports Server (NTRS)

McConnell, B. S.; Wilt, G. L.; Gillespie, A.; Newsom, H. E.

2005-01-01

We studied small, uniquely-shaped craters found on the surface of lineated terrain in the Ismenius Lacus region of Mars. By utilizing MOC and THEMIS satellite images, we located terrain including lineations (viscous flow features), smoothing of topography, and morphologic features such as polygons and gullies, which appear to be strong evidence of preexisting ice deposits.

Lytro camera technology: theory, algorithms, performance analysis

NASA Astrophysics Data System (ADS)

Georgiev, Todor; Yu, Zhan; Lumsdaine, Andrew; Goma, Sergio

2013-03-01

The Lytro camera is the first implementation of a plenoptic camera for the consumer market. We consider it a successful example of the miniaturization aided by the increase in computational power characterizing mobile computational photography. The plenoptic camera approach to radiance capture uses a microlens array as an imaging system focused on the focal plane of the main camera lens. This paper analyzes the performance of Lytro camera from a system level perspective, considering the Lytro camera as a black box, and uses our interpretation of Lytro image data saved by the camera. We present our findings based on our interpretation of Lytro camera file structure, image calibration and image rendering; in this context, artifacts and final image resolution are discussed.

Image quality prediction - An aid to the Viking lander imaging investigation on Mars

NASA Technical Reports Server (NTRS)

Huck, F. O.; Wall, S. D.

1976-01-01

Image quality criteria and image quality predictions are formulated for the multispectral panoramic cameras carried by the Viking Mars landers. Image quality predictions are based on expected camera performance, Mars surface radiance, and lighting and viewing geometry (fields of view, Mars lander shadows, solar day-night alternation), and are needed in diagnosis of camera performance, in arriving at a preflight imaging strategy, and revision of that strategy should the need arise. Landing considerations, camera control instructions, camera control logic, aspects of the imaging process (spectral response, spatial response, sensitivity), and likely problems are discussed. Major concerns include: degradation of camera response by isotope radiation, uncertainties in lighting and viewing geometry and in landing site local topography, contamination of camera window by dust abrasion, and initial errors in assigning camera dynamic ranges (gains and offsets).

Widespread Layers in Arabia Terra: Implications for Martian Geologic History

NASA Technical Reports Server (NTRS)

Venechuk, Elizabeth M.; Oehler, D. Z.

2006-01-01

Layered rocks in Arabia Terra have been the focus of several recent papers. Studies have focused on the layers found in crater basins located in the southwest portion of the region. However, Mars Orbiter Camera (MOC) images have identified layered deposits across the region. Terrestrial layered rocks are usually sedimentary, and often deposited in water. Thus extensive layered sequences in Arabia Terra may indicate locations of past, major depositional basins on Mars. Other mechanisms can also create layered rocks, or the appearance of layered rocks, including volcanism (both lava flows and ash falls), wind-blown deposits, and wave-cut terraces at shorelines. By identifying where in the region layers occur, and classifying the layers according to morphology and albedo, past depositional environments may be identified. Arabia Terra is characterized by heavily cratered Noachian plains, as well as a rise from -4000 m in the northwest to 4000 m in the southeast (Mars Orbital Laser Altimeter [MOLA] datum). This slope may have provided a constraint on sediment deposition and thus layer formation. While most of the region is Noachian in age, a significant percentage of the area is identified as Hesperian. Although the history of the Arabia Terra initially seems to be straightforward cratered plains with several younger units atop them analysis of high-resolution imagery may reveal a more complex history.

Mars South Polar Cap "Fingerprint" Terrain

NASA Image and Video Library

2000-04-24

This picture is illuminated by sunlight from the upper left. Some portions of the martian south polar residual cap have long, somewhat curved troughs instead of circular pits. These appear to form in a layer of material that may be different than that in which "swiss cheese" circles and pits form, and none of these features has any analog in the north polar cap or elsewhere on Mars. This picture shows the "fingerprint" terrain as a series of long, narrow depressions considered to have formed by collapse and widening by sublimation of ice. Unlike the north polar cap, the south polar region stays cold enough in summer to retain frozen carbon dioxide. Viking Orbiter observations during the late 1970s showed that very little water vapor comes off the south polar cap during summer, indicating that any frozen water that might be there remains solid throughout the year. This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image was obtained in early southern spring on August 4, 1999. It shows an area 3 x 5 kilometers (1.9 x 3.1 miles) at a resolution of about 7.3 meters (24 ft) per pixel. Located near 86.0°S, 53.9°W. http://photojournal.jpl.nasa.gov/catalog/PIA02373

Basin-Wide Oceanographic Array Bridges the South Atlantic

NASA Astrophysics Data System (ADS)

Ansorge, I. J.; Baringer, M. O.; Campos, E. J. D.; Dong, S.; Fine, R. A.; Garzoli, S. L.; Goni, G.; Meinen, C. S.; Perez, R. C.; Piola, A. R.; Roberts, M. J.; Speich, S.; Sprintall, J.; Terre, T.; Van den Berg, M. A.

2014-02-01

The meridional overturning circulation (MOC) is a global system of surface, intermediate, and deep ocean currents. The MOC connects the surface layer of the ocean and the atmosphere with the huge reservoir of the deep sea and is the primary mechanism for transporting heat, freshwater, and carbon between ocean basins. Climate models show that past changes in the strength of the MOC were linked to historical climate variations. Further research suggests that the MOC will continue to modulate climate change scenarios on time scales ranging from decades to centuries [Latif et al., 2006].

The Relationship between MOC Reflex and Masked Threshold

PubMed Central

Garinis, Angela; Werner, Lynne; Abdala, Carolina

2011-01-01

Otoacoustic emission (OAE) amplitude can be reduced by acoustic stimulation. This effect is produced by the medial olivocochlear (MOC) reflex. Past studies have shown that the MOC reflex is related to listening in noise and attention. In the present study, the relationship between strength of the contralateral MOC reflex and masked threshold was investigated in 19 adults. Detection thresholds were determined for a 1000-Hz, 300-ms tone presented simultaneously with one repetition of a 300-ms masker in an ongoing train of 300-ms masker bursts at 600-ms intervals. Three masking conditions were tested: 1) broadband noise 2) a fixed-frequency 4-tone complex masker and 3) a random-frequency 4-tone complex masker. Broadband noise was expected to produce energetic masking and the tonal maskers were expected to produce informational masking in some listeners. DPOAEs were recorded at fine frequency interval from 500 to 4000 Hz, with and without contralateral acoustic stimulation. MOC reflex strength was estimated as a reduction in baseline level and a shift in frequency of DPOAE fine-structure maxima near 1000-Hz. MOC reflex and psychophysical testing were completed in separate sessions. Individuals with poorer thresholds in broadband noise and in random-frequency maskers were found to have stronger MOC reflexes. PMID:21878379

Maintenance of Certification for Radiation Oncology

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kun, Larry E.; Ang, Kian; Erickson, Beth

2005-06-01

Maintenance of Certification (MOC) recognizes that in addition to medical knowledge, several essential elements involved in delivering quality care must be developed and maintained throughout one's career. The MOC process is designed to facilitate and document professional development of American Board of Radiology (ABR) diplomates in the essential elements of quality care in Radiation Oncology and Radiologic Physics. ABR MOC has been developed in accord with guidelines of the American Board of Medical Specialties. All Radiation Oncology certificates issued since 1995 are 10-year, time-limited certificates; diplomates with time-limited certificates who wish to maintain specialty certification must complete specific requirements ofmore » the American Board of Radiology MOC program. Diplomates with lifelong certificates are not required to participate but are strongly encouraged to do so. Maintenance of Certification is based on documentation of participation in the four components of MOC: (1) professional standing, (2) lifelong learning and self-assessment, (3) cognitive expertise, and (4) performance in practice. Through these components, MOC addresses six competencies-medical knowledge, patient care, interpersonal and communication skills, professionalism, practice-based learning and improvement, and systems-based practice. Details of requirements for components 1, 2, and 3 of MOC are outlined along with aspects of the fourth component currently under development.« less

Motion Estimation Utilizing Range Detection-Enhanced Visual Odometry

NASA Technical Reports Server (NTRS)

Morris, Daniel Dale (Inventor); Chang, Hong (Inventor); Friend, Paul Russell (Inventor); Chen, Qi (Inventor); Graf, Jodi Seaborn (Inventor)

2016-01-01

A motion determination system is disclosed. The system may receive a first and a second camera image from a camera, the first camera image received earlier than the second camera image. The system may identify corresponding features in the first and second camera images. The system may receive range data comprising at least one of a first and a second range data from a range detection unit, corresponding to the first and second camera images, respectively. The system may determine first positions and the second positions of the corresponding features using the first camera image and the second camera image. The first positions or the second positions may be determined by also using the range data. The system may determine a change in position of the machine based on differences between the first and second positions, and a VO-based velocity of the machine based on the determined change in position.

What's in It for Me? Maintenance of Certification as an Incentive for Faculty Supervision of Resident Quality Improvement Projects.

PubMed

Rosenbluth, Glenn; Tabas, Jeffrey A; Baron, Robert B

2016-01-01

Residents are required to engage in quality improvement (QI) activities, which requires faculty engagement. Because of increasing program requirements and clinical demands, faculty may be resistant to taking on additional teaching and supervisory responsibilities without incentives. The authors sought to create an authentic benefit for University of California, San Francisco (UCSF) Pediatrics Residency Training Program faculty who supervise pediatrics residents' QI projects by offering maintenance of certification (MOC) Part 4 (Performance in Practice) credit. The authors identified MOC as an ideal framework to both more actively engage faculty who were supervising QI projects and provide incentives for doing so. To this end, in 2011, the authors designed an MOC portfolio program which included faculty development, active supervision of residents, and QI projects designed to improve patient care. The UCSF Pediatrics Residency Training Program's Portfolio Sponsor application was approved by the American Board of Pediatrics (ABP) in 2012, and faculty whose projects were included in the application were granted MOC Part 4 credit. As of December 2013, six faculty had received MOC Part 4 credit for their supervision of residents' QI projects. Based largely on the success of this program, UCSF has transitioned to the MOC portfolio program administered through the American Board of Medical Specialties, which allows the organization to offer MOC Part 4 credit from multiple specialty boards including the ABP. This may require refinements to screening, over sight, and reporting structures to ensure the MOC standards are met. Ongoing faculty development will be essential.

Application of Sensor Fusion to Improve Uav Image Classification

NASA Astrophysics Data System (ADS)

Jabari, S.; Fathollahi, F.; Zhang, Y.

2017-08-01

Image classification is one of the most important tasks of remote sensing projects including the ones that are based on using UAV images. Improving the quality of UAV images directly affects the classification results and can save a huge amount of time and effort in this area. In this study, we show that sensor fusion can improve image quality which results in increasing the accuracy of image classification. Here, we tested two sensor fusion configurations by using a Panchromatic (Pan) camera along with either a colour camera or a four-band multi-spectral (MS) camera. We use the Pan camera to benefit from its higher sensitivity and the colour or MS camera to benefit from its spectral properties. The resulting images are then compared to the ones acquired by a high resolution single Bayer-pattern colour camera (here referred to as HRC). We assessed the quality of the output images by performing image classification tests. The outputs prove that the proposed sensor fusion configurations can achieve higher accuracies compared to the images of the single Bayer-pattern colour camera. Therefore, incorporating a Pan camera on-board in the UAV missions and performing image fusion can help achieving higher quality images and accordingly higher accuracy classification results.

Internists' Views of Maintenance of Certification: A Stages-of-Change Perspective

ERIC Educational Resources Information Center

Arnold, Gerald K.; Hess, Brian J.; Lipner, Rebecca S.

2013-01-01

Introduction: Board certification has evolved from a "point-in-time" event to a process of periodic learning and reevaluation of medical competence through maintenance of certification (MOC). To better understand MOC participation, the transtheoretical model (TTM) was used to describe physicians' perceptions of MOC as a sequence of…

Synthesis and characterization of mangan oxide coated sand from Capkala kaolin

NASA Astrophysics Data System (ADS)

Destiarti, Lia; Wahyuni, Nelly; Prawatya, Yopa Eka; Sasri, Risya

2017-03-01

Synthesis and characterization of mangan oxide coated sand from quartz sand fraction of Capkala kaolin has been conducted. There were two methods on synthesis of Mangan Oxide Coated Sand (MOCS) from Capkala Kaolin compared in this research. Characterization of MOCS was done by using Scanning Electron Microscope/Energy Dispersive X-Ray Spectrometer (SEM/EDX) and X-Ray Diffraction (XRD). The MOCS was tested to reduce phosphate in laundry waste. The result showed that the natural sand had bigger agregates and a relatively uniform structural orientation while both MOCS had heterogen structural orientation and manganese oxide formed in cluster. Manganese in first and second methods were 1,93% and 2,63%, respectively. The XRD spectrum showed clear reflections at 22,80°, 36,04°, 37,60° and a broad band at 26,62° (SiO2). Based on XRD spectrum, it can be concluded that mineral constituents of MOCS was verified corresponding to pyrolusite (MnO2). The former MOCS could reduce almost 60% while the later could reduce 70% phosphate in laundry waste.

Maintenance of Certification®, Maintenance of Public Trust

PubMed Central

Chung, Kevin C.; Clapham, Philip J.; Lalonde, Donald H.

2010-01-01

The Maintenance of Certification® (MOC) program has been well received by many physicians, but faced significant opposition from others, who complain that it is overly tedious, costly, and irrelevant to their practice. This article offers a consolidated and concise history of the MOC program and a summary of what plastic surgeons need to know to successfully complete the American Board of Plastic Surgery’s (ABPS) own MOC requirements. The authors have justified each step of the ABPS’s MOC process in terms of how it improves the quality of care delivered to Plastic Surgery patients. Finally, a summary of research is presented that demonstrates both that the public supports the MOC process for all physicians and that continuing education and formal assessment and improvement initiatives have been linked in multiple studies to a better and more evidence-based medical practice. PMID:21285803

MO-B-19A-01: MOC: A How-To Guide

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ibbott, G; Seibert, J; Allison, J

2014-06-15

Medical physicists who were certified in 2002 or later, as well as those who become certified in the future, are enrolled in Maintenance of Certification. Many physicists with life-time certificates have voluntarily enrolled in MOC, as have physicists who volunteer their time to participate in the ABR exam development and administration processes. MOC consists of four components: Part 1, Professional standing; Part 2, Lifelong learning and self-assessment; Part 3, Cognitive expertise; and Part 4, Practice quality improvement. These four components together evaluate six competencies: Medical knowledge, patient care and procedural skills, interpersonal and communication skills, professionalism, practice-based learning and improvement,more » and systems-based practice. Parts 1, 2, and 3 of MOC are fairly straightforward, although many participants have questions about the process for attesting to professional standing, the opportunities for obtaining self-assessed continuing education, and the timing of the cognitive exam. MOC participants also have questions about Part 4, Practice Quality Improvement. PQI projects are powerful tools for improving the quality and safety of the environments in which we practice medical physics. In the current version of MOC known as “Continuous Certification” a medical physicist must have completed a PQI project within the previous three years, at the time of the ABR's annual look-back each March. For the first “full” annual look-back in March 2016, diplomates will be given an additional year, so that a PQI project completed in 2012, 2013, 2014, or 2015 will fulfill this requirement. Each component of MOC will be addressed, and the specifics of interest to medical physicists will be discussed. Learning Objectives: Understand the four components and six competencies evaluated by MOC. Become familiar with the annual requirements of Continuous Certification. Learn about opportunities for Practice Quality Improvement projects. Understand refinements occurring in the MOC program.« less

FDG PET/CT findings in a case of myositis ossificans circumscripta of the forearm.

PubMed

Clarençon, Frédéric; Larousserie, Frédérique; Babinet, Antoine; Zylbersztein, Christophe; Talbot, Jean-Noël; Kerrou, Khaldoun

2011-01-01

Myositis ossificans circumscripta (MOC) is a rare benign neoplasm located in soft tissues that, most of the time, appears after a local trauma. The positive diagnosis of MOC may be challenging on CT or MRI findings. We report on an atypical case of a spontaneous nontraumatic MOC in a 54-year-old man, located in the longus supinatus muscle diagnosed with MRI and F-18 FDG PET/CT findings. Rarely described F-18 FDG PET/CT features in MOC are presented. Pattern of avid FDG focus on PET/CT, that may wrongly suggest osteosarcoma, is presented.

An implicit dispersive transport algorithm for the US Geological Survey MOC3D solute-transport model

USGS Publications Warehouse

Kipp, K.L.; Konikow, Leonard F.; Hornberger, G.Z.

1998-01-01

This report documents an extension to the U.S. Geological Survey MOC3D transport model that incorporates an implicit-in-time difference approximation for the dispersive transport equation, including source/sink terms. The original MOC3D transport model (Version 1) uses the method of characteristics to solve the transport equation on the basis of the velocity field. The original MOC3D solution algorithm incorporates particle tracking to represent advective processes and an explicit finite-difference formulation to calculate dispersive fluxes. The new implicit procedure eliminates several stability criteria required for the previous explicit formulation. This allows much larger transport time increments to be used in dispersion-dominated problems. The decoupling of advective and dispersive transport in MOC3D, however, is unchanged. With the implicit extension, the MOC3D model is upgraded to Version 2. A description of the numerical method of the implicit dispersion calculation, the data-input requirements and output options, and the results of simulator testing and evaluation are presented. Version 2 of MOC3D was evaluated for the same set of problems used for verification of Version 1. These test results indicate that the implicit calculation of Version 2 matches the accuracy of Version 1, yet is more efficient than the explicit calculation for transport problems that are characterized by a grid Peclet number less than about 1.0.

Image Sensors Enhance Camera Technologies

NASA Technical Reports Server (NTRS)

2010-01-01

In the 1990s, a Jet Propulsion Laboratory team led by Eric Fossum researched ways of improving complementary metal-oxide semiconductor (CMOS) image sensors in order to miniaturize cameras on spacecraft while maintaining scientific image quality. Fossum s team founded a company to commercialize the resulting CMOS active pixel sensor. Now called the Aptina Imaging Corporation, based in San Jose, California, the company has shipped over 1 billion sensors for use in applications such as digital cameras, camera phones, Web cameras, and automotive cameras. Today, one of every three cell phone cameras on the planet feature Aptina s sensor technology.

Awareness of and Participation in Maintenance of Professional Certification: A Prospective Study

ERIC Educational Resources Information Center

Bower, Elizabeth A.; Choi, Dongseok; Becker, Thomas M.; Girard, Donald E.

2007-01-01

Introduction: National health care concerns have led to the emergence of maintenance of certification (MOC) as a means to ensure the competence of practicing physicians. Little is known about physician perceptions of the barriers and/or benefits of MOC or proportions of physicians who participate in MOC programs. The purposes of this study were to…

A comparison of select image-compression algorithms for an electronic still camera

NASA Technical Reports Server (NTRS)

Nerheim, Rosalee

1989-01-01

This effort is a study of image-compression algorithms for an electronic still camera. An electronic still camera can record and transmit high-quality images without the use of film, because images are stored digitally in computer memory. However, high-resolution images contain an enormous amount of information, and will strain the camera's data-storage system. Image compression will allow more images to be stored in the camera's memory. For the electronic still camera, a compression algorithm that produces a reconstructed image of high fidelity is most important. Efficiency of the algorithm is the second priority. High fidelity and efficiency are more important than a high compression ratio. Several algorithms were chosen for this study and judged on fidelity, efficiency and compression ratio. The transform method appears to be the best choice. At present, the method is compressing images to a ratio of 5.3:1 and producing high-fidelity reconstructed images.

Capturing method for integral three-dimensional imaging using multiviewpoint robotic cameras

NASA Astrophysics Data System (ADS)

Ikeya, Kensuke; Arai, Jun; Mishina, Tomoyuki; Yamaguchi, Masahiro

2018-03-01

Integral three-dimensional (3-D) technology for next-generation 3-D television must be able to capture dynamic moving subjects with pan, tilt, and zoom camerawork as good as in current TV program production. We propose a capturing method for integral 3-D imaging using multiviewpoint robotic cameras. The cameras are controlled through a cooperative synchronous system composed of a master camera controlled by a camera operator and other reference cameras that are utilized for 3-D reconstruction. When the operator captures a subject using the master camera, the region reproduced by the integral 3-D display is regulated in real space according to the subject's position and view angle of the master camera. Using the cooperative control function, the reference cameras can capture images at the narrowest view angle that does not lose any part of the object region, thereby maximizing the resolution of the image. 3-D models are reconstructed by estimating the depth from complementary multiviewpoint images captured by robotic cameras arranged in a two-dimensional array. The model is converted into elemental images to generate the integral 3-D images. In experiments, we reconstructed integral 3-D images of karate players and confirmed that the proposed method satisfied the above requirements.

Megapixel mythology and photospace: estimating photospace for camera phones from large image sets

NASA Astrophysics Data System (ADS)

Hultgren, Bror O.; Hertel, Dirk W.

2008-01-01

It is a myth that more pixels alone result in better images. The marketing of camera phones in particular has focused on their pixel numbers. However, their performance varies considerably according to the conditions of image capture. Camera phones are often used in low-light situations where the lack of a flash and limited exposure time will produce underexposed, noisy and blurred images. Camera utilization can be quantitatively described by photospace distributions, a statistical description of the frequency of pictures taken at varying light levels and camera-subject distances. If the photospace distribution is known, the user-experienced distribution of quality can be determined either directly by direct measurement of subjective quality, or by photospace-weighting of objective attributes. The population of a photospace distribution requires examining large numbers of images taken under typical camera phone usage conditions. ImagePhi was developed as a user-friendly software tool to interactively estimate the primary photospace variables, subject illumination and subject distance, from individual images. Additionally, subjective evaluations of image quality and failure modes for low quality images can be entered into ImagePhi. ImagePhi has been applied to sets of images taken by typical users with a selection of popular camera phones varying in resolution. The estimated photospace distribution of camera phone usage has been correlated with the distributions of failure modes. The subjective and objective data show that photospace conditions have a much bigger impact on image quality of a camera phone than the pixel count of its imager. The 'megapixel myth' is thus seen to be less a myth than an ill framed conditional assertion, whose conditions are to a large extent specified by the camera's operational state in photospace.

Contralateral Inhibition of Click- and Chirp-Evoked Human Compound Action Potentials

PubMed Central

Smith, Spencer B.; Lichtenhan, Jeffery T.; Cone, Barbara K.

2017-01-01

Cochlear outer hair cells (OHC) receive direct efferent feedback from the caudal auditory brainstem via the medial olivocochlear (MOC) bundle. This circuit provides the neural substrate for the MOC reflex, which inhibits cochlear amplifier gain and is believed to play a role in listening in noise and protection from acoustic overexposure. The human MOC reflex has been studied extensively using otoacoustic emissions (OAE) paradigms; however, these measurements are insensitive to subsequent “downstream” efferent effects on the neural ensembles that mediate hearing. In this experiment, click- and chirp-evoked auditory nerve compound action potential (CAP) amplitudes were measured electrocochleographically from the human eardrum without and with MOC reflex activation elicited by contralateral broadband noise. We hypothesized that the chirp would be a more optimal stimulus for measuring neural MOC effects because it synchronizes excitation along the entire length of the basilar membrane and thus evokes a more robust CAP than a click at low to moderate stimulus levels. Chirps produced larger CAPs than clicks at all stimulus intensities (50–80 dB ppeSPL). MOC reflex inhibition of CAPs was larger for chirps than clicks at low stimulus levels when quantified both in terms of amplitude reduction and effective attenuation. Effective attenuation was larger for chirp- and click-evoked CAPs than for click-evoked OAEs measured from the same subjects. Our results suggest that the chirp is an optimal stimulus for evoking CAPs at low stimulus intensities and for assessing MOC reflex effects on the auditory nerve. Further, our work supports previous findings that MOC reflex effects at the level of the auditory nerve are underestimated by measures of OAE inhibition. PMID:28420960

The American Board of Internal Medicine Maintenance of Certification Examination and State Medical Board Disciplinary Actions: a Population Cohort Study.

PubMed

McDonald, Furman S; Duhigg, Lauren M; Arnold, Gerald K; Hafer, Ruth M; Lipner, Rebecca S

2018-03-07

Some have questioned whether successful performance in the American Board of Internal Medicine (ABIM) Maintenance of Certification (MOC) program is meaningful. The association of the ABIM Internal Medicine (IM) MOC examination with state medical board disciplinary actions is unknown. To assess risk of disciplinary actions among general internists who did and did not pass the MOC examination within 10 years of initial certification. Historical population cohort study. The population of internists certified in internal medicine, but not a subspecialty, from 1990 through 2003 (n = 47,971). ABIM IM MOC examination. General internal medicine in the USA. The primary outcome measure was time to disciplinary action assessed in association with whether the physician passed the ABIM IM MOC examination within 10 years of initial certification, adjusted for training, certification, demographic, and regulatory variables including state medical board Continuing Medical Education (CME) requirements. The risk for discipline among physicians who did not pass the IM MOC examination within the 10 year requirement window was more than double than that of those who did pass the examination (adjusted HR 2.09; 95% CI, 1.83 to 2.39). Disciplinary actions did not vary by state CME requirements (adjusted HR 1.02; 95% CI, 0.94 to 1.16), but declined with increasing MOC examination scores (Kendall's tau-b coefficient = - 0.98 for trend, p < 0.001). Among disciplined physicians, actions were less severe among those passing the IM MOC examination within the 10-year requirement window than among those who did not pass the examination. Passing a periodic assessment of medical knowledge is associated with decreased state medical board disciplinary actions, an important quality outcome of relevance to patients and the profession.

Image Mosaicking Approach for a Double-Camera System in the GaoFen2 Optical Remote Sensing Satellite Based on the Big Virtual Camera.

PubMed

Cheng, Yufeng; Jin, Shuying; Wang, Mi; Zhu, Ying; Dong, Zhipeng

2017-06-20

The linear array push broom imaging mode is widely used for high resolution optical satellites (HROS). Using double-cameras attached by a high-rigidity support along with push broom imaging is one method to enlarge the field of view while ensuring high resolution. High accuracy image mosaicking is the key factor of the geometrical quality of complete stitched satellite imagery. This paper proposes a high accuracy image mosaicking approach based on the big virtual camera (BVC) in the double-camera system on the GaoFen2 optical remote sensing satellite (GF2). A big virtual camera can be built according to the rigorous imaging model of a single camera; then, each single image strip obtained by each TDI-CCD detector can be re-projected to the virtual detector of the big virtual camera coordinate system using forward-projection and backward-projection to obtain the corresponding single virtual image. After an on-orbit calibration and relative orientation, the complete final virtual image can be obtained by stitching the single virtual images together based on their coordinate information on the big virtual detector image plane. The paper subtly uses the concept of the big virtual camera to obtain a stitched image and the corresponding high accuracy rational function model (RFM) for concurrent post processing. Experiments verified that the proposed method can achieve seamless mosaicking while maintaining the geometric accuracy.

Methods for identification of images acquired with digital cameras

NASA Astrophysics Data System (ADS)

Geradts, Zeno J.; Bijhold, Jurrien; Kieft, Martijn; Kurosawa, Kenji; Kuroki, Kenro; Saitoh, Naoki

2001-02-01

From the court we were asked whether it is possible to determine if an image has been made with a specific digital camera. This question has to be answered in child pornography cases, where evidence is needed that a certain picture has been made with a specific camera. We have looked into different methods of examining the cameras to determine if a specific image has been made with a camera: defects in CCDs, file formats that are used, noise introduced by the pixel arrays and watermarking in images used by the camera manufacturer.

Plateaus and sinuous ridges as the fingerprints of lava flow inflation in the Eastern Tharsis Plains of Mars

NASA Astrophysics Data System (ADS)

Bleacher, Jacob E.; Orr, Tim R.; de Wet, Andrew P.; Zimbelman, James R.; Hamilton, Christopher W.; Brent Garry, W.; Crumpler, Larry S.; Williams, David A.

2017-08-01

The Tharsis Montes rift aprons are composed of outpourings of lava from chaotic terrains to the northeast and southwest flank of each volcano. Sinuous and branching channel networks that are present on the rift aprons suggest the possibility of fluvial processes in their development, or erosion by rapidly emplaced lavas, but the style of lava flow emplacement throughout rift apron development is not clearly understood. To better characterize the style of lava emplacement and role of fluvial processes in rift apron development, we conducted morphological mapping of the Pavonis Mons southwest rift apron and the eastern Tharsis plains using images from the High Resolution Imaging Science Experiment (HiRISE), Mars Orbiter Camera (MOC), Context Camera (CTX), Thermal Emission Imaging System (THEMIS), and High Resolution Stereo Camera (HRSC) along with the Mars Orbiter Laser Altimeter (MOLA) Precision Experiment Data Records (PEDRs) and gridded data. Our approach was to: (1) search for depositional fans at the slope break between the rift apron and adjacent low slope plains; (2) determine if there is evidence that previously formed deposits might have been buried by plains units; (3) characterize the Tharsis plains morphologies east of Pavonis Mons; and (4) assess their relationship to the rift apron units. We have not identified topographically significant depositional fans, nor did we observe evidence to suggest that plains units have buried older rift apron units. Flow features associated with the rift apron are observed to continue across the slope break onto the plains. In this area, the plains are composed of a variety of small fissures and low shield vents around which broad channel-fed and tube-fed flows have been identified. We also find broad, flat-topped plateaus and sinuous ridges mixed among the channels, tubes and vents. Flat-topped plateaus and sinuous ridges are morphologies that are analogous to those observed on the coastal plain of Hawai'i, where lava flows have advanced from the volcano's several degree flank onto the nearly zero degree coastal plain. When local volumetric flow rates are low, flow fronts tend to spread laterally and often thicken via endogenous growth, or inflation, of the sheet-like flow units. If flow advance is restricted by existing topography into narrow pathways, inflation can be focused into sinuous, elongate ridges. The presence of plateaus and ridges-emplaced from the rift zones, across the plains to the east of Pavonis Mons-and a lack of fan-like features, or evidence for their burial, are consistent with rift apron lavas crossing a slope break with low local volumetric flow rates that led to inflation of sheet-like and tube-fed lava flows.

Plateaus and Sinuous Ridges as the Fingerprints of Lava Flow Inflation in the Eastern Tharsis Plains of Mars

NASA Technical Reports Server (NTRS)

Bleacher, Jacob E.; Orr, Tim R.; de Wet, Andrew P.; Zimbelman, James R.; Hamilton, Christopher W.; Garry, W. Brent; Crumpler, Larry S.; Williams, David A.

2017-01-01

The Tharsis Montes rift aprons are composed of outpourings of lava from chaotic terrains to the northeast and southwest flank of each volcano. Sinuous and branching channel networks that are present on the rift aprons suggest the possibility of fluvial processes in their development, or erosion by rapidly emplaced lavas, but the style of lava flow emplacement throughout rift apron development is not clearly understood. To better characterize the style of lava emplacement and role of fluvial processes in rift apron development, we conducted morphological mapping of the Pavonis Mons southwest rift apron and the eastern Tharsis plains using images from the High Resolution Imaging Science Experiment (HiRISE), Mars Orbiter Camera (MOC), Context Camera (CTX), Thermal Emission Imaging System (THEMIS), and High Resolution Stereo Camera (HRSC) along with the Mars Orbiter Laser Altimeter (MOLA) Precision Experiment Data Records (PEDRs) and gridded data. Our approach was to: (1) search for depositional fans at the slope break between the rift apron and adjacent low slope plains; (2) determine if there is evidence that previously formed deposits might have been buried by plains units; (3) characterize the Tharsis plains morphologies east of Pavonis Mons; and (4) assess their relationship to the rift apron units. We have not identified topographically significant depositional fans, nor did we observe evidence to suggest that plains units have buried older rift apron units. Flow features associated with the rift apron are observed to continue across the slope break onto the plains. In this area, the plains are composed of a variety of small fissures and low shield vents around which broad channel-fed and tube-fed flows have been identified. We also find broad, flat-topped plateaus and sinuous ridges mixed among the channels, tubes and vents. Flat-topped plateaus and sinuous ridges are morphologies that are analogous to those observed on the coastal plain of Hawai'i, where lava flows have advanced from the volcano's several degree flank onto the nearly zero degree coastal plain. When local volumetric flow rates are low, flow fronts tend to spread laterally and often thicken via endogenous growth, or inflation, of the sheet-like flow units. If flow advance is restricted by existing topography into narrow pathways, inflation can be focused into sinuous, elongate ridges. The presence of plateaus and ridges-emplaced from the rift zones, across the plains to the east of Pavonis Mons-and a lack of fan-like features, or evidence for their burial, are consistent with rift apron lavas crossing a slope break with low local volumetric flow rates that led to inflation of sheet-like and tube-fed lava flows.

Plateaus and sinuous ridges as the fingerprints of lava flow inflation in the Eastern Tharsis Plains of Mars

USGS Publications Warehouse

Bleacher, Jacob E.; Orr, Tim R.; de Wet, Andrew P.; Zimbelman, James R.; Hamilton, Christopher W.; Garry, W. Brent; Crumpler, Larry S.; Williams, David A.

2017-01-01

The Tharsis Montes rift aprons are composed of outpourings of lava from chaotic terrains to the northeast and southwest flank of each volcano. Sinuous and branching channel networks that are present on the rift aprons suggest the possibility of fluvial processes in their development, or erosion by rapidly emplaced lavas, but the style of lava flow emplacement throughout rift apron development is not clearly understood. To better characterize the style of lava emplacement and role of fluvial processes in rift apron development, we conducted morphological mapping of the Pavonis Mons southwest rift apron and the eastern Tharsis plains using images from the High Resolution Imaging Science Experiment (HiRISE), Mars Orbiter Camera (MOC), Context Camera (CTX), Thermal Emission Imaging System (THEMIS), and High Resolution Stereo Camera (HRSC) along with the Mars Orbiter Laser Altimeter (MOLA) Precision Experiment Data Records (PEDRs) and gridded data. Our approach was to: (1) search for depositional fans at the slope break between the rift apron and adjacent low slope plains; (2) determine if there is evidence that previously formed deposits might have been buried by plains units; (3) characterize the Tharsis plains morphologies east of Pavonis Mons; and (4) assess their relationship to the rift apron units. We have not identified topographically significant depositional fans, nor did we observe evidence to suggest that plains units have buried older rift apron units. Flow features associated with the rift apron are observed to continue across the slope break onto the plains. In this area, the plains are composed of a variety of small fissures and low shield vents around which broad channel-fed and tube-fed flows have been identified. We also find broad, flat-topped plateaus and sinuous ridges mixed among the channels, tubes and vents. Flat-topped plateaus and sinuous ridges are morphologies that are analogous to those observed on the coastal plain of Hawai‘i, where lava flows have advanced from the volcano's several degree flank onto the nearly zero degree coastal plain. When local volumetric flow rates are low, flow fronts tend to spread laterally and often thicken via endogenous growth, or inflation, of the sheet-like flow units. If flow advance is restricted by existing topography into narrow pathways, inflation can be focused into sinuous, elongate ridges. The presence of plateaus and ridges—emplaced from the rift zones, across the plains to the east of Pavonis Mons—and a lack of fan-like features, or evidence for their burial, are consistent with rift apron lavas crossing a slope break with low local volumetric flow rates that led to inflation of sheet-like and tube-fed lava flows.

Maintenance of certification: current attitudes of members of the American Society of Neuroradiology.

PubMed

Yousem, D M

2008-02-01

The maintenance of certification (MOC) process has begun in radiology, and many physicians will be affected by it. We sought to assess the compliance with and knowledge of the MOC steps by American Society of Neuroradiology (ASNR) members. An on-line survey was distributed via e-mail to the members of the ASNR for whom e-mail addresses were available. The survey addressed 3 components of the MOC currently implemented: 1) MOC cognitive examinations, 2) self-assessment modules (SAMs), and 3) continuing medical education (CME) credits. The response rate was 1020/2662 (38.3%). Of those responding, 11% stated that they either do not support the MOC examination (8%) or were unaware of it (3%), 21.4% of respondents have completed an SAM module, but >30% were unaware that they had to complete SAMs or did not know where they were offered. Many members will receive most of their 25 required CME hours for 2007 from sources besides the ASNR annual meeting. Of the small proportion of respondents who made comments (247/1020, 24.2%), those about the MOC process were favorable in 6.1% (15/247), unfavorable in 46.6% (115/247), and neutral in 47.4% (117/247). The MOC process remains poorly understood, with limited compliance. The radiology societies should spend additional effort publicizing the requirements and offering support and products aimed at allowing their members to achieve compliance in a reasonable cost-effective fashion.

Automatic calibration method for plenoptic camera

NASA Astrophysics Data System (ADS)

Luan, Yinsen; He, Xing; Xu, Bing; Yang, Ping; Tang, Guomao

2016-04-01

An automatic calibration method is proposed for a microlens-based plenoptic camera. First, all microlens images on the white image are searched and recognized automatically based on digital morphology. Then, the center points of microlens images are rearranged according to their relative position relationships. Consequently, the microlens images are located, i.e., the plenoptic camera is calibrated without the prior knowledge of camera parameters. Furthermore, this method is appropriate for all types of microlens-based plenoptic cameras, even the multifocus plenoptic camera, the plenoptic camera with arbitrarily arranged microlenses, or the plenoptic camera with different sizes of microlenses. Finally, we verify our method by the raw data of Lytro. The experiments show that our method has higher intelligence than the methods published before.

Modulated electron-multiplied fluorescence lifetime imaging microscope: all-solid-state camera for fluorescence lifetime imaging.

PubMed

Zhao, Qiaole; Schelen, Ben; Schouten, Raymond; van den Oever, Rein; Leenen, René; van Kuijk, Harry; Peters, Inge; Polderdijk, Frank; Bosiers, Jan; Raspe, Marcel; Jalink, Kees; Geert Sander de Jong, Jan; van Geest, Bert; Stoop, Karel; Young, Ian Ted

2012-12-01

We have built an all-solid-state camera that is directly modulated at the pixel level for frequency-domain fluorescence lifetime imaging microscopy (FLIM) measurements. This novel camera eliminates the need for an image intensifier through the use of an application-specific charge coupled device design in a frequency-domain FLIM system. The first stage of evaluation for the camera has been carried out. Camera characteristics such as noise distribution, dark current influence, camera gain, sampling density, sensitivity, linearity of photometric response, and optical transfer function have been studied through experiments. We are able to do lifetime measurement using our modulated, electron-multiplied fluorescence lifetime imaging microscope (MEM-FLIM) camera for various objects, e.g., fluorescein solution, fixed green fluorescent protein (GFP) cells, and GFP-actin stained live cells. A detailed comparison of a conventional microchannel plate (MCP)-based FLIM system and the MEM-FLIM system is presented. The MEM-FLIM camera shows higher resolution and a better image quality. The MEM-FLIM camera provides a new opportunity for performing frequency-domain FLIM.

Digital camera with apparatus for authentication of images produced from an image file

NASA Technical Reports Server (NTRS)

Friedman, Gary L. (Inventor)

1993-01-01

A digital camera equipped with a processor for authentication of images produced from an image file taken by the digital camera is provided. The digital camera processor has embedded therein a private key unique to it, and the camera housing has a public key that is so uniquely based upon the private key that digital data encrypted with the private key by the processor may be decrypted using the public key. The digital camera processor comprises means for calculating a hash of the image file using a predetermined algorithm, and second means for encrypting the image hash with the private key, thereby producing a digital signature. The image file and the digital signature are stored in suitable recording means so they will be available together. Apparatus for authenticating at any time the image file as being free of any alteration uses the public key for decrypting the digital signature, thereby deriving a secure image hash identical to the image hash produced by the digital camera and used to produce the digital signature. The apparatus calculates from the image file an image hash using the same algorithm as before. By comparing this last image hash with the secure image hash, authenticity of the image file is determined if they match, since even one bit change in the image hash will cause the image hash to be totally different from the secure hash.

Polar Polygons

NASA Technical Reports Server (NTRS)

2004-01-01

26 December 2003 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) picture displays polygons outlined by cracks in the martian south polar region. This southern summer view was acquired in October 2003 and is located near 86.9oS, 170.6oW. Polygons similar in size and shape to these are common in the arctic and antarctic regions of Earth. On Earth, they indicate the presence (or the past presence) of ground ice and the freeze-thaw cycles that accompany this ice. On Mars, whether ground ice was responsible for these landforms is uncertain, but their presence is suggestive that ground ice may exist or may once have existed in this region. The picture covers an area 3 km (1.9 mi) wide. Sunlight illuminates the scene from the upper left.

Plenoptic camera image simulation for reconstruction algorithm verification

NASA Astrophysics Data System (ADS)

Schwiegerling, Jim

2014-09-01

Plenoptic cameras have emerged in recent years as a technology for capturing light field data in a single snapshot. A conventional digital camera can be modified with the addition of a lenslet array to create a plenoptic camera. Two distinct camera forms have been proposed in the literature. The first has the camera image focused onto the lenslet array. The lenslet array is placed over the camera sensor such that each lenslet forms an image of the exit pupil onto the sensor. The second plenoptic form has the lenslet array relaying the image formed by the camera lens to the sensor. We have developed a raytracing package that can simulate images formed by a generalized version of the plenoptic camera. Several rays from each sensor pixel are traced backwards through the system to define a cone of rays emanating from the entrance pupil of the camera lens. Objects that lie within this cone are integrated to lead to a color and exposure level for that pixel. To speed processing three-dimensional objects are approximated as a series of planes at different depths. Repeating this process for each pixel in the sensor leads to a simulated plenoptic image on which different reconstruction algorithms can be tested.

Gone But Not Forgotten: The Aeolian Modification of Fluvial Surfaces on Mars: Preliminary Results from Central Australia

NASA Technical Reports Server (NTRS)

Bourke, M. C.

2003-01-01

MOC images indicate that aeolian ridges may mask and even obliterate primary depositional surfaces on Mars. This modification increases the difficulty in mapping the recent geological history of the planet. An analogue study in central Australia demonstrates how patterns in aeolian dunes, formed over abandoned fluvial surfaces, can be used to detect buried fluvial features.