|
|
Olympus Mons, 1998
| title |
Olympus Mons, 1998 |
| date |
04.25.1998 |
| description |
Olympus Mons is a mountain of mystery. Taller than three Mount Everests and about as wide as the entire Hawaiian Island chain, this giant volcano is nearly as flat as a pancake. That is, its flanks typically only slope 20 to 50. The Mars Orbiter Camera (MOC) obtained this spectacular wide-angle view of Olympus Mons on Mars Global Surveyor's 263rd orbit, around 10:40 p.m. PDT on April 25, 1998. In the view presented here, north is to the left and east is up. The spacecraft was traveling from north to south (left to right). Although the camera looks straight down (towards the nadir) and cannot be pointed to the side, the wide angle camera has such a large field of view (it sees from horizon to horizon) that, in effect, it provides side looking views. Unlike some other MOC images, that have had to be warped to provide a view as if seen from a certain direction and altitude, this image shows what the camera saw without additional processing. It is easy to imagine that you are looking out a window at the surface of Mars from about 900 km (560 miles) up. The image was taken on a cool, crisp winter morning. The west side of the volcano (lower portion of view, above) was clear and details on the surface appear very sharp. The skies above the plains to the east of Olympus Mons (upper portion of view) were cloudy. Clouds were lapping against the lower east flanks of this 26 kilometers (16 miles) high volcano, but the summit skies were clear. When Mars Global Surveyor attains its Mapping Orbit in March 1999, the MOC wide angle camera system will be used to make daily, global maps of martian clouds and weather systems. The wide angle images will resemble weather satellite pictures of Earth, and will help the Mars science teams plan their observations and test computer-driven Mars weather prediction models. 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. Image Note: This color picture was made using MOC red wide angle image 26301 and blue wide angle image 26302. The green channel was synthesized by averaging the red and blue bands. Color is not the true color of Mars as it would appear to the human eye (the actual colors would be more pale and contrast more subdued) *Image Credit*: NASA/JPL/Malin Space Science Systems |
|
'Happy Face' Crater
| title |
'Happy Face' Crater |
| date |
03.10.1999 |
| description |
Mars Global Surveyor was greeted with this view of 'Happy Face Crater' smiling back at its camera from its location on the east side of Argyre Planitia. This crater is officially known as Galle Crater, and it is about 215 kilometers (134 miles) across. The picture was taken by the MOC's red and blue wide angle cameras. The bluish-white tone is caused by wintertime frost. Illumination is from the upper left. For more information and Viking Orbiter views of "Happy Face Crater," see http://www.msss.com/education/happy_face/happy_face.html. *Image Credit*: NASA |
|
Mars Climate Orbiter
| Title |
Mars Climate Orbiter |
| Full Description |
The Mars Surveyor '98 Climate Orbiter is shown here during acoustic tests that simulate launch conditions. The orbiter was to conduct a two year primary mission to profile the Martian atmosphere and map the surface. To carry out these scientific objectives, the spacecraft carried a rebuilt version of the pressure modulated infrared radiometer, lost with the Mars Observer spacecraft, and a miniaturized dual camera system the size of a pair of binoculars, provided by Malin Space Science Systems, Inc., San Diego, California. During its primary mission, the orbiter was to monitor Mars atmosphere and surface globally on a daily basis for one Martian year (two Earth years), observing the appearance and movement of atmospheric dust and water vapor, as well as characterizing seasonal changes of the planet's surface. Imaging of the surface morphology would also provide important clues about the planet's climate in its early history. The mission was part of NASA's Mars Surveyor program, a sustained program of robotic exploration of the red planet, managed by the Jet Propulsion Laboratory for NASA's Office of Space Science, Washington, DC. Lockheed Martin Astronautics was NASA's industrial partner in the mission. Unfortunately, Mars Climate Orbiter burned up in the Martian atmosphere on September 23, 1999, due to a metric conversion error that caused the spacecraft to be off course. |
| Date |
05/27/1998 |
| NASA Center |
Jet Propulsion Laboratory |
|
Solar System Montage
| Title |
Solar System Montage |
| Full Description |
This is a montage of planetary images taken by spacecraft managed by the Jet Propulsion Laboratory in Pasadena, CA. Included are (from top to bottom) images of Mercury, Venus, Earth (and Moon), Mars, Jupiter, Saturn, Uranus and Neptune. The spacecraft responsible for these images are as follows: the Mercury image was taken by Mariner 10, the Venus image by Magellan, the Earth image by Galileo, the Mars image by Viking, and the Jupiter, Saturn, Uranus and Neptune images by Voyager. Pluto is not shown as no spacecraft has yet visited it. The inner planets (Mercury, Venus, Earth, Moon, and Mars) are roughly to scale to each other, the outer planets (Jupiter, Saturn, Uranus, and Neptune) are roughly to scale to each other. Actual diameters are given below: Sun 1,390,000 km Mercury 4,879 km Venus 12,104 km Earth 12,756 km Moon 3,475 km Mars 6,794 km Jupiter 142.984 km Saturn 120,536 km Uranus 51,118 km Neptune 49,528 km Pluto 2,390 km |
| Date |
04/09/1999 |
| NASA Center |
Jet Propulsion Laboratory |
|
Evidence for Recent Liquid W
…
| Title |
Evidence for Recent Liquid Water on Mars |
| Full Description |
Gullies eroded into the wall of a meteor impact crater in Noachis Terra. This high resolution view (top left) from the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) shows channels and associated aprons of debris that are interpreted to have formed by groundwater seepage, surface runoff, and debris flow. The lack of small craters superimposed on the channels and apron deposits indicates that these features are geologically young. It is possible that these gullies indicate that liquid water is present within the martian subsurface today. The MOC image was acquired on September 28, 1999. The scene covers an area approximately 3 kilometers (1.9 miles) wide by 6.7 km (4.1 mi) high (note, the aspect ratio is 1.5 to 1.0). Sunlight illuminates this area from the upper left. The image is located near 54.8S, 342.5W. The context image (above) shows the location of the MOC image on the south-facing wall of an impact crater approximately 20 kilometers (12 miles) in diameter. The context picture was obtained by the Viking 1 orbiter in 1980 and is illuminated from the upper left. The large mound on the floor of the crater in the context view is a sand dune field. The Mars Orbiter Camera 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 brief description of how the color was generated: The MOC narrow angle camera only takes grayscale (black and white) pictures. To create the color versions seen here, we have taken much lower resolution red and blue images acquired by the MOC's wide angle cameras, and by the Viking Orbiter cameras in the 1970s, synthesized a green image by averaging red and blue, and created a pallete of colors that represent the range of colors on Mars. We then use a relationship that correlates color and brightness to assign a color to each gray level. This is only a crude approximation of martian color. It is likely Mars would not look like this to a human observer at Mars. |
| Date |
06/22/2000 |
| NASA Center |
Jet Propulsion Laboratory |
|
FIDO Rover
| Title |
FIDO Rover |
| Full Description |
The Field Integrated Design and Operations (FIDO) rover is being used in ongoing NASA field tests to simulate driving conditions on Mars. FIDO is at a geologically interesting site in central Nevada while it is controlled from the mission control room at JPL's Planetary Robotics Laboratory in Pasadena. FIDO uses a robot arm to manipulate science instruments and it has a new mini-corer or drill to extract and cache rock samples. Several camera systems onboard allow the rover to collect science and navigation images by remote-control. The rover is about the size of a coffee table and weighs as much as a St. Bernard, about 70 kilograms (150 pounds). It is approximately 85 centimeters (about 33 inches) wide, 105 centimeters (41 inches) long, and 55 centimeters (22 inches) high. The rover moves up to 300 meters an hour (less than a mile per hour) over smooth terrain, using its onboard stereo vision systems to detect and avoid obstacles as it travels "on-the-fly." During these tests, FIDO is powered by both solar panels that cover the top of the rover and by replaceable, rechargeable batteries. |
| Date |
04/01/1999 |
| NASA Center |
Jet Propulsion Laboratory |
|
FIDO Rover Retracted Arm and
…
| Title |
FIDO Rover Retracted Arm and Camera |
| Full Description |
The Field Integrated Design and Operations (FIDO) rover extends the large mast that carries its panoramic camera. The FIDO is being used in ongoing NASA field tests to simulate driving conditions on Mars. FIDO is controlled from the mission control room at JPL's Planetary Robotics Laboratory in Pasadena. FIDO uses a robot arm to manipulate science instruments and it has a new mini-corer or drill to extract and cache rock samples. Several camera systems onboard allow the rover to collect science and navigation images by remote-control. The rover is about the size of a coffee table and weighs as much as a St. Bernard, about 70 kilograms (150 pounds). It is approximately 85 centimeters (about 33 inches) wide, 105 centimeters (41 inches) long, and 55 centimeters (22 inches) high. The rover moves up to 300 meters an hour (less than a mile per hour) over smooth terrain, using its onboard stereo vision systems to detect and avoid obstacles as it travels "on-the-fly." During these tests, FIDO is powered by both solar panels that cover the top of the rover and by replaceable, rechargeable batteries. |
| Date |
04/01/1999 |
| NASA Center |
Jet Propulsion Laboratory |
|
Wide Angle View of Arsia Mon
…
| Title |
Wide Angle View of Arsia Mons Volcano |
| Description |
Arsia Mons (above) is one of the largest volcanoes known. This shield volcano is part of an aligned trio known as the Tharsis Montes--the others are Pavonis Mons and Ascraeus Mons. Arsia Mons is rivaled only by Olympus Mons in terms of its volume. The summit of Arsia Mons is more than 9 kilometers (5.6 miles) higher than the surrounding plains. The crater--or caldera--at the volcano summit is approximately 110 km (68 mi) across. This view of Arsia Mons was taken by the red and blue wide angle cameras of the Mars Global Surveyor Mars Orbiter Camera (MOC) system. Bright water ice clouds (the whitish/bluish wisps) hang above the volcano--a common sight every martian afternoon in this region. Arsia Mons is located at 120o west longitude and 9o south latitude. Illumination is from the left. |
| Date |
09.28.1999 |
|
Melas Chasma
| title |
Melas Chasma |
| Description |
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 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 3 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 10.1°S, 74.4°W and was acquired on July 11, 1999. North is toward the lower left. Photo Credit: NASA/JPL/Malin Space Science Systems |
|
Happy Face" Crater
| title |
Happy Face" Crater |
| Description |
The story of the Mars Orbiter Camera (MOC) onboard the Mars Global Surveyor (MGS) spacecraft began with a proposal to NASA in 1985. The first MOC flew on Mars Observer, a spacecraft that was lost before it reached the red planet in 1993. Now, after 14 years of effort, a MOC has finally been placed in the desired mapping orbit. The MOC team's happiness is perhaps best expressed by the planet Mars itself. On the first day of the Mapping Phase of the MGS mission--during the second week of March 1999--MOC was greeted with this view of "Happy Face Crater" (center right) smiling back at the camera from its location on the east side of Argyre Planitia. This crater is officially known as Galle Crater, and it is about 215 kilometers (134 miles) across. The picture was taken by the MOC's red and blue wide angle cameras. The bluish-white tone is caused by wintertime frost. Illumination is from the upper left. For more information and Viking Orbiter views of "Happy Face Crater," see http://www.msss.com/education/happy_face/happy_face.html [ http://www.msss.com/education/happy_face/happy_face.html ]. Photo Credit: NASA/JPL/Malin Space Science Systems |
|
Topographic Views of Mars
| title |
Topographic Views of Mars |
| Description |
With one year of global mapping of the Mars Global Surveyor mission completed, the MOLA dataset has achieved excellent spatial and vertical resolution. The maps [ http://photojournal.jpl.nasa.gov/catalog/PIA01049 ] have been produced from the altimetric observations collected during MOLA's first year of global mapping and provide a variety of regional topographic views of the Martian surface. The maps were compiled from a database of 266.7 million laser altimetric measurements collected between March 1, 1999 and February 29, 2000. In each map the spatial resolution is approximately 1/16° by 1/32° (where 1° on Mars is about 59 km) and the vertical accuracy is approximately 1 meter. Note that the sizes of the regions vary. |
|
Promethei Terra
| title |
Promethei Terra |
| Description |
In December 1999, the MOC team finally had an answer! A dust devil, shown in the above figure, was caught in the act of creating a swirly, dark streak! An eerie sensation washed over the first team members who saw this picture---here was an event on Mars "caught in the act" just hours before the picture was played back to Earth. A "smoking gun." The first dust devil seen making a streak---located in Promethei Terra---was traveling from right (east) to left (west). A columnar shadow was cast by sunlight coming from the upper left. This shadow indicates the true shape of the dust devil. The bright dust devil itself does not look like a column because the picture was taken from a camera looking straight down on it. The dust devil is less than 100 meters (less than 100 yards) wide and the picture covers an area approximately 1.5 by 1.7 kilometers (about 1 by 1 mile). 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. They 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. On Earth, dust devils typically last for only a few minutes. Photo Credit: NASA/JPL/Malin Space Science Systems |
|
Syrtis Major and Arabia Terr
…
| title |
Syrtis Major and Arabia Terra |
| Description |
The Mars Global Surveyor Mars Orbiter Camera (MOC) has, in fact, three cameras. The narrow angle system obtains monochrome (black-and-white) super-high resolution views of the red planet, while the wide angle system obtains regional and global views in both the red and blue portions of the visible spectrum (to make a color image, the red and blue are averaged to obtain the green channel). The picture shown here is a composite of 9 color strips taken by the MOC on 9 successive orbits from pole-to-pole over the planet during the calibration phase of the mission in March 1999. The large, circular bright region that dominates the scene is Arabia Terra. Syrtis Major is the dark region toward the lower right. The north polar cap is visible at the top, and the bright feature at the lower right is the Hellas Basin. The color in this picture is computer-enhanced and is not shown as it would actually appear to the human eye. 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. Photo Credit: NASA/JPL/Malin Space Science Systems |
|
Mars Daily Global Image from
…
| title |
Mars Daily Global Image from April 1999 |
| Description |
Twelve orbits a day provide the Mars Global Surveyor MOC wide angle cameras a global "snapshot" of weather patterns across the planet. Here, bluish-white water ice clouds hang above the Tharsis volcanoes. This computer generated image was created by wrapping the global map found at PIA02066 [ http://photojournal.jpl.nasa.gov/cgi-bin/GenCatalogPage.pl?PIA02066 ] onto a sphere. The center of this newly projected sphere is located at 15 degrees North, 90 degrees West. This perspective rotates the south pole (which has no data coverage in the original map) away from our field of view. 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. Photo Credit: NASA/JPL/Malin Space Science Systems |
|
A Mid-Northern Summer/Southe
…
| title |
A Mid-Northern Summer/Southern Winter's Mars |
| Description |
MGS MOC Release No. MOC2-325, 04 April 2003 The Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) began its daily global imaging campaign four years ago, on March 9, 1999. Since that time, slightly more than 2 full Martian years have elapsed, and MOC has obtained a complete daily record of the red planet's ever-changing weather patterns. Observing Mars every day over many years is critical to understanding how to forecast weather that may occur in the future, and MOC is the only U.S. instrument slated to orbit Mars until late 2006 that can provide this information. For example, the MOC team has found that many weather events repeat from one year to the next. Such knowledge is useful in considering where future spacecraft might land on Mars---a site that is known to experience a dust storm each year during the period a lander or rover will be operational might not be a good place to land. The six views of Mars shown here are a composite of the 24 daily global images acquired by MOC on February 14, 2003. At this time, it was the middle of summer in the northern hemisphere, and the middle of winter in the south. Taken together, the six views show the entire planet, its albedo (bright and dark) features, polar frosts, and cloud patterns. Water-ice clouds dominate the martian atmosphere over the tropical and sub-tropical latitudes, while orographically-generated (i.e. those associated with high-standing topography) water-ice clouds hang over each of the large volcanoes of the Tharsis and Elysium regions (see MOC2-326a, MOC2-326b, MOC326f). In the north polar region, the residual water-ice cap is fully exposed. In the southern hemisphere, the winter-time seasonal carbon dioxide frost cap can be seen, extending from the south pole (which is in darkness and not seen in these images) northward to 50°S latitude. In the deep Hellas Basin (an ancient, giant impact scar seen as the bright elliptical feature at the bottom of MOC2-326e), the winter-time cap extends northward to 31°S because the lower elevation permits carbon dioxide to freeze at slightly higher temperatures than at the high elevations elsewhere in the southern hemisphere. When these pictures were taken on February 14, 2003, dust storm activity was at a minimum and isolated to early morning hours around the edges of the north polar cap. Within a day, however, dust storm activity began to pick up in both hemispheres--as was expected from previous MOC images at this time of year in 1999 and 2001--and dust storms remained active through the rest of February and March. Images Credit: NASA/JPL/Malin Space Science Systems Caption by: B. C. Cantor, K. S. Edgett, and M. C. Malin, MSSS |
|
Layers and a Dust Devil in M
…
| title |
Layers and a Dust Devil in Melas Chasma |
| Description |
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 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 10.1°S, 74.4°W and was acquired on July 11, 1999. North is toward the lower left. Photo Credit: NASA/JPL/Malin Space Science Systems |
|
Spallanzani Crater
| title |
Spallanzani Crater |
| Description |
Although most of the best examples of layered sedimentary rock seen on Mars are found at equatorial and sub-tropical latitudes, a few locations seen at mid- and high-latitudes suggest that layered rocks are probably more common than we can actually see from orbit. One extremely good example of these "atypical" layered rock exposures is found in the 72 km-diameter (45 miles) crater, Spallanzani (58.4°S, 273.5°W). Located southeast of Hellas Planitia, the crater is named for the 18th Century Italian biologist, Lazzaro Spallanzani (1729-1799). Picture A presents a composite of the best Viking orbiter image (VO2-504B55) of the region with 4 pictures obtained June 1999 through January 2001 by the Mars Global Surveyor Mars Orbiter Camera (MOC). Each MOC narrow angle image is 3 km across. Taken in the MOC's "survey mode," all four images were acquired at roughly 12 meters (39 ft) per pixel. Picture B zooms-in on the portion of the composite image that includes the 4 MOC images (the 100%-size view is 20 m (66 ft) per pixel). Other craters in the region near Spallanzani show features--at Viking Orbiter scale--that are reminiscent of the layering seen in Spallanzani. Exactly what these layers are made of and how they came to be where we see them today are mysteries, but it is possible that they are similar to the materials seen in the many craters and chasms of the equatorial latitudes on Mars. Images Credit: NASA/JPL/Malin Space Science Systems |
|
Mid-Winter Dust Storms Near
…
| title |
Mid-Winter Dust Storms Near Hellas Planitia |
| Description |
One of the primary objectives for the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) during the Extended Mission is to continue daily monitoring of martian weather as expressed in clouds, dust storms, and patches of polar frost. During the Primary Mission, which lasted from March 1999 through January 2001, changes that occurred over a single martian year (687 Earth days) were observed. Now it is possible to see what the martian atmosphere will do for at least two-thirds of a second martian year, because the Extended Mission will run into April 2002. This picture captures two dust storms, each large enough to cover Arizona or New Mexico. One is located near the lower left, the other at the lower right. Taken on April 8, 2001 (mid-southern winter), this is a mosaic of six MOC daily global images centered around Hellas Planitia in the martian southern hemisphere. Hellas Planitia is the dominant elliptical feature just below the center of the picture. The bright, nearly white surfaces along the lower (southern) edge of the picture are covered by wintertime frost. The strong temperature difference between the winter frost and the warmer air just off the edge of this polar cap generates winds that---at this time of year---are often strong enough to lift dust into large, reddish-brown, billowy clouds. North is up and sunlight illuminates the area from the upper left. The martian equator forms the arc along the top of the picture, 500 kilometers (km) is equal to about 311 miles. The approximately 500 kilometer-wide circular feature just above the center is the crater Huygens. Image Credit: NASA/JPL/Malin Space Science Systems |
|
Highest-Resolution View of "
…
| title |
Highest-Resolution View of "Face on Mars |
| Description |
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 24.8° 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. An earlier picture obtained in June 2000 was combined with the new, April 2001 image, to produce a stereo ("3-D") view of the western portion of the hill ("3-D" glasses with red for left eye and blue for right eye are needed to view the anaglyph). The large "face" picture, above, covers an area about 3.6 kilometers (2.2 miles) on a side, the 3-D picture [ http://www.msss.com/mars_images/moc/extended_may2001/face/index.html ] is about 1 km (0.62 mi) wide. Sunlight illuminates the images from the left/lower left. Images Credit: NASA/JPL/Malin Space Science Systems |
|
Changes Over a Martian Year
…
| title |
Changes Over a Martian Year -- New Dark Slope Streaks in Lycus Sucli |
| Description |
Now in its Extended Mission, Mars Global Surveyor (MGS) is into its second Mars year of systematic observations of the red planet. With the Extended Mission slated to run through April 2002, the Mars Orbiter Camera (MOC) is being used, among other things, to look for changes that have occurred in the past martian year. Because Mars is farther from the Sun than Earth, its year is longer---about 687 Earth days. The two pictures shown here cover the same portion of Lycus Sulci, a rugged, ridged terrain north of the giant Olympus Mons volcano. The interval between the pictures span 92% of a martian year (August 2, 1999 to April 27, 2001). Dark streaks considered to result from the avalanching of dry, fine, bright dust are seen in both images. The disruption of the surface by the avalanching materials is thought to cause them to appear darker than their surroundings, just as the 1997 bouncing of Mars Pathfinder's airbags and the tire tracks made by the Sojourner rover left darkened markings indicating where the martian soil had been disrupted and disturbed. The arrows in the April 2001 picture indicate eight new streaks that formed on these slopes in Lycus Sulci since August 1999. These observations suggest that a new streak forms approximately once per martian year per kilometer (about 0.62 miles) along a slope. In both images, north is toward the top/upper right and sunlight illuminates each from the left. Dark (as well bright) slope streaks are most common in the dust-covered martian regions of Tharsis, Arabia, and Elysium. Additional examples of dark slope streaks can be seen in the following earlier MOC image media releases: * "Recent Movements: New Landslides in Less than 1 Martian Year," March 12, 2000 [ http://www.msss.com/mars_images/moc/lpsc2000/3_00_massmovement/ ] * "Dark Slope Streaks on Elysium Basin Buttes," July 19, 1999 [ http://www.msss.com/mars_images/moc/7_19_99_fifthMars/18_slopes/ ] Images Credit: NASA/JPL/Malin Space Science Systems |
|
Happy 8th Birthday, MGS
| title |
Happy 8th Birthday, MGS |
| Description |
. The reason there is no MOC image for April 1999 is a product of the MGS spacecraft's 8-year history at Mars. MGS was certainly in orbit at the time, and it was taking data during the month of April. However, the camera did not obtain any images between 17 and 28 April because the spacecraft encountered, and then had to be recovered from, a problem. It was at this time that the spacecraft team realized that there is something obstructing the full movement of MGS's high gain antenna. A work-around was created and the mission has continued, ever since, but the down-side was that MOC did not have the opportunity in 1999 to provide detailed observations of the north polar, summertime, annular cloud. The remaining three pictures show MGS MOC views of the cloud feature, as it appeared in the subsequent 3 Mars years. Each year, the cloud appeared at about the same time or slightly earlier than in the previous year. Despite its superficial resemblance to a hurricane or cyclone on Earth, the northern summer annular cloud does not rotate. The cloud forms as different currents of air merge in the morning hours in the polar region, by afternoon, the annular cloud typically dissipates or breaks up into smaller clouds. MGS MOC has observed other repeated phenomena over the course of its 8-year mission orbiting Mars. These include dust storms that repeat, year after year, in the same location within a week or two of the time it occurred in the previous year. They also include dust devils in northern Amazonis, which start up shortly after the first day of spring, and keep occurring nearly every afternoon until a few days into the autumn season. MOC is continuing its mission to monitor the planet -- in 2006, MOC's weather observations will be used to provide guidance for the aerobraking maneuvers of the Mars Reconnaissance Orbiter (MRO). MOC images will show whether dust storms are occurring, and whether the dust suspended by these storms will impact the density of the atmosphere at the altitudes that MRO is passing through to slow the spacecraft and change its orbit to the one desired for the MRO primary mission. Location Near: 90°N Season: Northern Summer Credit: NASA/JPL/MSSS, Mars Global Surveyor (MGS) entered Mars orbit on 12 September 1997. Today, we celebrate the MGS's 8th anniversary! The 8 Earth years that MGS has been in orbit span portions of 5 martian years. One of the critical science activities that the Mars Orbiter Camera (MOC) has been engaged in for the past 8 years has been to document daily changes in the martian weather. Each day that MOC is operating, the red and blue wide angle cameras are used to build up a daily global map. These maps provide a record of the planet's changing meteorological conditions. One of the most exciting observations that the MOC wide angle cameras have made during these 8 years is that the red planet has very repeatable weather patterns. In light of weather-related problems and disruptions that occur every year on Earth, one can only imagine how nice it would be if our planet followed a similar, repeated pattern. The four pictures shown here provide an example of one of the weather phenomena that repeat each martian year. Each picture shows the north polar region of Mars during the northern summer season. Each picture is a composite of several images acquired at different visible wavelengths to give a color view of the planet. Each picture was taken about 1 Mars year apart, and each shows an annular (circular) cloud located over the same terrain each summer. The first picture, acquired in April 1999, is actually not from the MGS MOC instrument. It was obtained by the Hubble Space Telescope (HST) Wide Field Planetary Camera 2 (WFPC2) and was originally released by the Space Telescope Science Institute on 19 May 1999 [ http://hubblesite.org/newscenter/newsdesk/archive/releases/1999/22/ ] |
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Rolling Stones Make New Boul
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Rolling Stones Make New Boulder Tracks |
| Description |
When a boulder rolls down a dusty slope, it can leave behind a trail of depressions. Usually known as boulder tracks, these features have been documented and studied on Earth, the Moon, and Mars. Geologists studying the Moon and Mars can use these tracks to learn about the physical properties of the fine-grained debris encountered by the boulder as it rolled down the slope. Because of the high-resolution capability (0.5 to 12 meters, 1.6 to 39 feet, per pixel) of the Mars Orbiter Camera on NASA's Mars Global Surveyor spacecraft, dozens of boulder track sites have been identified on the red planet. A Mars Orbiter Camera image of one set of boulder tracks in a south mid-latitude crater (located near 35.8 degrees south latitude, 158.4 degrees west longitude) was obtained on Nov. 14, 2003, (left). A second image of the same site, from Dec. 4, 2004, (right) shows that more than a dozen new boulder tracks formed on the crater wall during the intervening time. Mars is an active planet, with geologic changes occurring -- at some scale -- every day. In this case, some time between mid November 2003 and early December 2004, a suite of boulders became dislodged from the crater wall, then rolled and perhaps bounced their way to the crater floor. Wider context for the site can be seen in a mosaic of Mars Orbiter Camera wide-angle images acquired in May 1999 (insert MOC2-1213a). The white box indicates the location of the later, higher-resolution views. Why the new boulders slid down the slope is unknown. This is the product of a mass movement (landsliding) process. That is, gravity is the main culprit. Whether the boulder motion was triggered by something -- a seismic event ("Marsquake") or strong winds -- is not known. Also unknown is whether all of the new boulder tracks formed at the same time, in response to a single event, or rolled downhill one at a time over the nearly 13-month period. The Mars Orbiter Camera was built and is operated by Malin Space Science Systems, San Diego, Calif. Mars Global Surveyor left Earth on Nov. 7, 1996, and began orbiting Mars on Sept. 12, 1997. JPL, a division of the California Institute of Technology, Pasadena, manages Mars Global Surveyor for NASA's Science Mission Directorate, Washington. Credit: NASA/JPL/MSSS |
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Scarp at Head of Chasma Bore
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Scarp at Head of Chasma Boreale |
| Description |
This view shows sharp detail of a scarp at the head of Chasma Boreale, a large trough cut by erosion into the martian north polar cap and the layered material beneath the ice cap. The picture is a mosaic of two images acquired in January 2005 by the Mars Orbiter Camera on NASA's Mars Global Surveyor, using a resolution-enhancing technique called "compensated pitch and roll targeted observation." The camera team considers this the best pair of images yet acquired using that technique. During each northern summer on Mars, there occurs a narrow window in time of two to three months when conditions are ideal to image the north polar cap at high resolution. Throughout this period, the atmosphere is generally clear over the cap, and the seasonal carbon-dioxide frost from the previous winter and spring has sublimed away, permitting a good view of the surface geology. The two images in this mosaic were acquired during this brief period during the most recent northern summer. Within a few weeks of when these images were acquired, dust storm activity picked up in the north polar region, making the atmosphere too dusty to obtain any more detailed views until late 2006. Chasma Boreale is cut into the layered material that lies beneath the water ice of the north polar cap. For decades, these layered materials were assumed to consist of a mixture of ice and dust. Mars Orbiter Camera images obtained in 1999 and 2001 began to show that some of the layers are a source for windblown sand. The science objective for the two images shown in this mosaic was to look for boulders in the debris shed from the steep slopes cut into the north polar layers by Chasma Boreale. Finding boulders would imply that the layers that are the most resistant to erosion in the polar region are as competent as solid rock, perhaps giving a new insight into the nature of the polar layered materials. The pictured site is near 84.8 degrees north latitude, 356.4 degrees west longitude. Examination of the high-resolution mosaic shows that there are indeed some large boulders that have eroded out of the layered materials and rolled down the slopes. It is possible, therefore, that the north polar layers are not simply a mixture of ice, dust, and sand. Some layers may actually be rock, cemented by minerals rather than by ice. Alternatively, if the materials are cemented by ice, then a future high-resolution view might show that the boulders have become smaller over time. In addition to the observation of boulders eroding out of the polar layered materials, the mosaic also helps confirm that dark sand is eroding out of the polar layered materials, and that there are three different groups of layers under the polar ice. The upper unit is light-toned, finely layered, and more resistant to erosion (more competent, less easily destroyed by erosion) than the middle unit, which is rich in dark sand but also has several shelf-forming layers in it. Finally, below the dark, sandy layer is a third unit, that is light-toned and has a different appearance relative to the other two units. Some of its layers have surfaces that have been broken by shallow fractures into polygonal and linear forms, also implying that they are hard, resistant rock. The level of detail seen in the mosaic was made possible by the development of a resolution-enhancing technique for using the Mars Orbiter Camera. During 2003 and 2004, the Mars Orbiter Camera operations team at Malin Space Science Systems, San Diego, Calif., worked closely with the Mars Global Surveyor operations teams at the Jet Propulsion Laboratory, Pasadena, Calif., and Lockheed Martin Space Systems, Denver, Colo., to develop a new technique in which the spacecraft does a maneuver that permits the camera to acquire images at a higher spatial resolution than normal. Usually, Mars Orbiter Camera images have a resolution of about 1.5 meters (5 feet) per pixel, and the camera can be commanded to acquire lower resolution data when desired. To obtain a higher resolution, the whole spacecraft must be pitched at such a rate that the camera over-samples its view of the martian surface in the down-track direction. Called compensated pitch and roll targeted observation, or cPROTO, this technique allows Mars Orbiter Camera to obtain images that have a resolution of about 50 centimeters (20 inches) per pixel in the down-track direction, and 150 centimeters (5 feet) per pixel in the cross-track dimension. The Mars Orbiter Camera was built and is operated by Malin Space Science Systems, San Diego, Calif. Mars Global Surveyor left Earth on Nov. 7, 1996, and began orbiting Mars on Sept. 12, 1997. JPL, a division of the California Institute of Technology, Pasadena, manages Mars Global Surveyor for NASA's Science Mission Directorate, Washington Credit: NASA/JPL/MSSS |
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Recently-Formed Impact Crate
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Recently-Formed Impact Crater |
| Description |
Scientists using the Mars Orbiter Camera on NASA's Mars Global Surveyor spacecraft have discovered a crater that appears to have formed on Mars in the past 20 or so Earth years, and have used it and several other similar craters to estimate the present cratering rate on Mars. One of the basic tenets of planetary geology is that impact craters have accumulated on planetary surfaces at roughly a constant rate since the early history of the solar system. This appears to have been the case for small craters on the surface of the Moon, as shown by measurements of the length of time that lunar rocks created by small impacts have been exposed to cosmic rays, as determined by laboratory measurements of samples returned to Earth by the Apollo astronauts. This principle should permit the number of craters found on a planetary surface to be used to determine the age of that surface, if the rate at which new craters form is known. Scientists have previously estimated the cratering rate of Mars by scaling the lunar cratering rate based on the proximity of Mars to the asteroid belt, and by performing calculations based on orbital mechanics. Another way to establish the cratering rate of Mars would be to use long-term observations, say, from orbiting spacecraft, to actually locate new craters. The new crater is located on the southern rim of the summit crater, or caldera, of the intermediate-sized martian volcano, Ulysses Patera. The site was imaged by the Viking 2 orbiter in 1976 (left, an enlarged portion of the image) and in narrow-angle views by the Mars Orbiter Camera in 1999 (center) and 2005 (right). The new crater, about 25 meters (82 feet) across, is marked by a distinct dark, rayed pattern of ejected material, or ejecta, which is seen to have faded somewhat between 1999 and 2005. Ulysses Patera, a volcanic shield about 100 kilometers (62 miles) in diameter volcanic shield, located near 2.5 degrees north latitude, 121.3 degrees west longitude, is one of the Tharsis volcanoes and is partly buried by younger lava flows. The summit caldera is about 55 kilometers (34 miles) in diameter. The amount that the crater's rays faded between 1999 and 2005 can be used to help estimate how many years ago the crater formed. The actual contrast between the ejecta and the undisturbed volcano summit materials is actually much less than it appears to be in these processed images, and the amount of fading is also much less. Images of disturbed surfaces from various parts of Mars, such as dust devil tracks, dark slope streaks and rover tracks, indicate that disturbed surfaces on Mars are dark and that they lighten with time. Using these other examples to estimate how dark the ejecta from the Ulysses crater was originally, and how much it has faded in six years, suggests the crater formed in the early to mid 1980s. The rate at which dark surfaces lighten on Mars is not uniform over the whole planet, but scientists using the Mars Orbiter Camera have found a number, of other craters with dark ejecta that have faded during the Mars Global Surveyor mission. The scientists estimate that these craters probably formed within the past 100 years. Although the sample is very small (the Mars Orbiter Camera narrow angle camera has imaged barely 4 percent of Mars), it appears that the recent cratering rate for craters on Mars 25 to 100 meters (82 to 328 feet) in diameter is about 0.000000003 to 0.000000006 craters per square kilometer (0.39 square mile) per Earth year, which is about five times lower than previous estimates. The site of the new crater is shown in wider context in a comparison of the 1976 Viking image with wide-angle views taken by the Mars Orbiter Camera in 1999 and 2005 (insert MOC2-1214b), and in even wider context in a regional mosaic of Viking images (insert MOC2-1214c). The Mars Orbiter Camera was built and is operated by Malin Space Science Systems, San Diego, Calif. Mars Global Surveyor left Earth on Nov. 7, 1996, and began orbiting Mars on Sept. 12, 1997. JPL, a division of the California Institute of Technology, Pasadena, manages Mars Global Surveyor for NASA's Science Mission Directorate, Washington. Credit: NASA/JPL/MSSS/USGS |
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Athabasca Vallis Streamlined
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Athabasca Vallis Streamlined "Islands |
| Description |
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. Images Credit: NASA/JPL/Malin Space Science Systems Caption by: K. S. Edgett and M. C. Malin, MSSS |
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Four Mars Years of South Pol
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| title |
Four Mars Years of South Polar Changes |
| Description |
One of the most profound discoveries that would not have been possible if NASA's Mars Global Surveyor mission had not been extended beyond its primary mission of one Mars year (687 Earth days) is that of dramatic changes that take place in the south polar residual ice cap each martian year. To make this discovery, the Mars Orbiter Camera on the spacecraft had to be employed during a second Mars year to repeat images of sites on the south polar cap that had been imaged during the primary mission. The initial discovery was made in 2001, when the camera team repeated images of portions of the south polar cap that had already been imaged in 1999. The goal of these images was to obtain stereo views, which would allow investigators to see the topography of the cap in three dimensions and to measure the thickness of the polar ice layers. It was not possible to produce the desired 3-D views. To the team's surprise, the landforms of the south polar cap had changed. The south polar residual cap -- that is, the portion of the ice cap that remains bright and retains ice throughout the southern summer season -- was seen in 1997 and 1999 images to have a complex terrain of broad, relatively flat mesas, small buttes, and many pits and troughs. Pits are generally circular and in some areas visually resemble a stack of thin slices of Swiss cheese. Very early in the Mars Global Surveyor mission, the Mars Orbiter Camera team speculated that these landforms must be carved into frozen carbon dioxide, because they look so unfamiliar and because Viking orbiter infrared measurements indicated that the south polar cap is cold enough consist of frozen carbon dioxide, even in summer. The observations made by Mars Orbiter Camera in 2001, during the first part of the extended mission, showed that the scarps and pit walls of the south polar cap had retreated at an average rate of about 3 meters (10 feet) since 1999. In other words, they were retreating 3 meters per Mars year (and, of course, most of that retreat takes place during the summer). In some places on the cap, the scarps retreat less than 3 meters a Mars year, and in others it can retreat as much as 8 meters (26 feet) per martian year. Of the two volatile materials one is likely to find in a frozen state on Mars -- water and carbon dioxide -- it is carbon dioxide that is volatile enough to permit scarp retreat rates like those observed by the Mars Orbiter Camera. Over time, south polar pits merge to become plains, mesas turn into buttes, and buttes vanish forever. Since 2001, two additional Mars years have elapsed. A scientific benefit of having a long extended mission for Mars Global Surveyor has been the opportunity to document how the polar cap is changing each year. Four images are shown here, plus an animation at left presenting the four frames in sequence. The location is near 86.3 degrees south latitude, 49.4 degrees west longitude, and the images show the same portion of the south polar residual, cap as it appeared in 1999, 2001, 2003, and 2005. Comparing the images or viewing the animation makes it evident that the landscape of the south polar cap has been changing rapidly over the past four martian years. Each year that Mars Global Surveyor has been in orbit, the landforms of the south polar residual cap have gotten smaller, and the carbon dioxide removed from the cap has not been re-deposited. The implication is that Mars presently has a warm (and possibly warming) climate, with new carbon dioxide going into the atmosphere every year. The other implication is that, at some time in the not-too-distant past, the planet had a colder climate, so that the layers of carbon dioxide could be deposited in the first place. If one takes the rate of scarp retreat and projects it backwards to fill in all of the pits and troughs with the carbon dioxide that has been removed from them, one finds that the colder climate might only have occurred a few centuries to a few tens of thousands of years ago. This kind of time scale is not unlike that of the climate changes that have been recorded on Earth, including the Ice Ages and the smaller fluctuations that have occurred since the last Ice Age (e.g., the "Little Ice Age" of the mid-14th through mid-19th centuries). After the discovery that the pits were enlarging and that we were not seeing carbon-dioxide deposition, it was suggested that interannual variations might be large enough to permit such deposition on a short timescale. However, two Mars years of additional observations show no large magnitude annual differences. Variations that would permit carbon dioxide deposition may require decades. And to see such variations may require many more Mars years of observations by orbiting spacecraft. The Mars Orbiter Camera was built and is operated by Malin Space Science Systems, San Diego, Calif. Mars Global Surveyor left Earth on Nov. 7, 1996, and began orbiting Mars on Sept. 12, 1997. JPL, a division of the California Institute of Technology, Pasadena, manages Mars Global Surveyor for NASA's Science Mission Directorate, Washington. Credit: NASA/JPL/MSSS |
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Spying Changes in Mars' Sout
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| title |
Spying Changes in Mars' South Polar Cap |
| Description |
This animated image shows Mars in motion over the last six years. Images from the Mars Orbiter Camera aboard the Mars Global Surveyor spacecraft have documented dramatic changes in the planet's south polar cap. 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 (arc-shaped slopes), 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 (nearly 10 feet) 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 (26 feet), in others, only 1 meter (3.3 feet) per Mars year. Credit: NASA/JPL/MSSS |
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Northern Terra Meridiani Roc
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Northern Terra Meridiani Rocks and Cliffs in 3-D |
| Description |
Extended Mission operations for the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) include opportunities that come up about 10 times a week to turn and point the MGS spacecraft so that MOC can photograph a feature of high scientific interest. Many of these images are targeted to the site of a previous MOC image, so that a stereoscopic ("3-D") view can be obtained. The top picture shows a 115 kilometers (~72 miles) wide portion of northern Terra Meridiani, a region of vast layered rock outcrops similar to portions of southeastern Utah and northern Arizona on Earth. The white box in this context image, located near 2.2°N, 1.3°W, shows the location of the high resolution stereo view obtained by MOC by combining a picture taken March 10, 1999 (FHA-00541) with one obtained by pointing the spacecraft on May 28, 2001 (EO4-02223). The stereo view, which requires red (left-eye) and blue (right-eye) "3-D" glasses to be seen, covers an area approximately 2.3 km (1.4 mi) wide by 6.2 km (3.9 mi) long. The full-resolution view is seen at nearly 1.5 meters (5 ft) per pixel, a scale at which objects the size of airplanes and school buses might be seen. The landscape revealed by the 3-D view is a rugged terrain with steep cliffs and no fresh impact craters. This terrain seems most un-Mars-like compared to the typical cratered and dusty views MOC has provided since it began taking data in September 1997. In fact, one of the MOC science team members remarked, "If I'd seen this landscape used in a movie about Mars five years ago, I'd have said the director had no clue what Mars is supposed to look like." An irregular depression with a flat, mottled, light-toned floor dominates the scene. Small dark ridges on the depression floor near the top center of the image are dunes or drifts formed by wind transport of sandy sediment. The sharp buttes, mesas, and steep cliffs are all indicators that this terrain consists of a broad exposure of martian bedrock. North is up and sunlight illuminates each picture from the left/upper left. Images Credit: NASA/JPL/Malin Space Science Systems |
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Erosion of North Polar Layer
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Erosion of North Polar Layers and Genesis of nearby Sand Dunes |
| Description |
The Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) is used by the MOC science team as a tool to test hypotheses about the geology, geomorphology, and meteorology of Mars. In 1999, MOC images revealed that the layers of the martian north polar cap are divided into two distinct units: an upper, light-toned sequence of layers, and a lower, darker-toned suite of layers. The team suspected that the lower unit, because of its dark tone and apparent association with nearby dune fields, might be a source of windblown sand. However, most of the 1999 images were of very low contrast because the frequent dust storms in the region made the atmosphere extremely hazy. Very few images of the north polar cap were obtained in 2000 because it was first hidden during the long winter's night, then coated by springtime frost. By early 2001, the north polar cap was in summer and the MOC team set out to test the idea that sand is eroding out of the lower unit. This picture, obtained in February 2001, shows streamers of dark sand coming from outcrops of the lower, dark-toned unit. The streamers join a nearby dune field less than a few kilometers (less than a mile) away. Erosion of the lower layered unit liberates sand that was long ago deposited in these layers. The upper unit, by contrast, contains almost no sand. Wind erosion of the lower unit leads to creation of steep scarps as the sand is removed and the upper unit is undermined. The sand moves downwind (in this case, toward the bottom left of the image) and creates dunes. The new views of the martian north polar cap obtained in 1999 and 2001 suggest that it may not contain as much water ice as previously believed. Indeed, the amount of ice may be as little as half of what was once thought. The picture shown here is 3 km (1.9 mi) wide and illuminated from the lower left. Another picture showing the upper and lower layered sequences of the north polar cap can be seen by clicking here: "MOC Extended Mission View of North Polar Layers," 11 February 2002. Photo Credit: NASA/JPL/Malin Space Science Systems |
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Martian North Polar Cap
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Martian North Polar Cap |
| Description |
Mars Global Surveyor's Mars Orbiter Camera obtained its last SPO-2 images of Mars on September 12, 1998. SPO-2, or 'Science Phasing Orbit-2', took place between early June and mid-September 1998. Shown above are MOC wide angle (red and blue band) images of the martian north polar region obtained around 3:15 a.m. PDT on September 12, 1998. This color composite was made using red and blue wide angle MOC images 55001 and 55002--these were the last pictures taken of the planet until the camera resumes its work in late-March 1999. The north polar layered deposits, a terrain believed composed of ice and dust deposited over millions of years, dominates this view. The swirled pattern in the images above are channels eroded into this deposit. The pattern is accentuated by the illumination and seasonal frost differences that arise on sun-facing slopes during the summer. The permanent portion of the north polar cap covers most of the region with a layer of ice of unknown thickness. At the time this picture was obtained, the martian northern hemisphere was in the midst of the early Spring season. The margin of the seasonal carbon dioxide frost cap was at about 67° N, so the ground throughout this image is covered by frost. The frost appears pink rather than white, this may result from textural changes in the frost as it sublimes or because the frost is contaminated by a small amount of reddish martian dust. Please note that these pictures have not been 'calibrated' and so the colors are not necessarily accurately portrayed. In addition to the north polar cap, the pictures also show some clouds (bluish-white wisps). Some of the clouds on the right side of the images are long, linear features that cast similar long, dark shadows on the ground beneath them. When the MOC resumes imaging of Mars in March 1999, summer will have arrived in the north polar regions and the area surrounding the permanent polar cap will appear much darker than it does here. The dark features surrounding the cap are sand dunes, and these are expected to darken over the next several months as seasonal ice sublimes and is removed from the surface. Photo Credit: NASA/JPL/Malin Space Science Systems |
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Martian "Swiss Cheese
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Martian "Swiss Cheese |
| Description |
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 bizzare landforms seen in this picture. The picture covers an area 3 x 9 kilometers (1.9 x 5.6 miles) near 85.6°S, 74.4°W 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. Photo Credit: NASA/JPL/Malin Space Science Systems |
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North Polar Cap in Summer
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North Polar Cap in Summer |
| Description |
In the middle of January 2001, Mars Global Surveyor (MGS) completed one Mars year in its ~380 km-high (236 mi) mapping orbit. The mapping orbit was originally achieved in late February 1999. In March of that year, MGS conducted a series of operations in preparation for full-up mapping, first calibrating its scientific instruments and then operating in a mode in which the high gain antenna was held fixed against the body of the spacecraft. During this Fixed High Gain Antenna period, 'contingency science' observations were made in case the high gain antenna failed to properly deploy. The wide angle view of the martian north polar cap shown on the left was acquired on March 13, 1999, during early northern summer. The image on the right was acquired almost exactly one Mars year later, on January 26, 2001. The light-toned surfaces are residual water ice that remains through the summer season. The nearly circular band of dark material surrounding the cap consists mainly of sand dunes formed and shaped by wind. The north polar cap is roughly 1100 kilometers (680 miles) across. Close inspection will show that there are differences in the frost cover between the two images (for example, in the upper center of each image, and on the left edge center). Although these changes appear small, they are in fact quite large--the change in frost covering is equivalent to the amount of frost that would be evaporated (in the case of areas that are darker) or deposited (in areas where frost is still on the ground) in almost 5 months. What gives rise to such large changes in the heat budget for the polar caps from one year to the next is not known. Changes in the coloration and brightness of the polar cap suggest dust, deposited perhaps by dust storms during critical periods of the year, may play an important role. Photo Credit: NASA/JPL/Malin Space Science Systems |
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Martian South Polar Pits in
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| title |
Martian South Polar Pits in Layer of Frozen Carbon Dioxide |
| Description |
One of the most profound benefits of being able to continue photographing Mars in the Mars Global Surveyor (MGS) Extended Mission is the opportunity to go back and re-image a site that was seen in the previous martian year. New MGS Mars Orbiter Camera (MOC) images have provided a startling observation: The residual martian south polar cap is changing. The fact that it is changing suggests that Mars may have major, global climate changes that are occurring on the same time scales as Earth's most recent climate shifts, including the last Ice Age. MOC images of the south polar cap taken in 1999 were compared with images of the same locations taken in 2001, and it was discovered that pits had enlarged, mesas had shrunk, and small buttes had vanished. In all, the scarps that enclose the pits and bound the mesas and buttes retreated about 3 meters (3.3 yards) in 1 martian year (687 Earth days). This rapid retreat of polar scarps can only occur if the ice is frozen carbon dioxide (also known as "dry ice"). Retreat of scarps made of water ice is much slower and would not have been measurable from one martian year to the next. The portion of the martian south polar cap that persists through summer is called the residual polar cap. The two sets of four pictures shown here are from four places on the residual south polar cap. The pictures from 1999 were taken in October of that year, the corresponding pictures from 2001 were acquired in August, approximately 1 Mars year after the 1999 images were obtained. In each case, the pictures are illuminated by sunlight from the upper left, and each shows an area about 250 meters (273 yards) across. The polar cap is layered, and the layers have eroded to form pits, troughs, mesas, and buttes. The pits form as sunlight warms frozen carbon dioxide during southern spring and summer, and the ice sublimes away. There is so much carbon dioxide that it does not all go away in one summer---in fact, it may take hundreds to thousands of years to disappear. These new observations indicate that the south polar residual cap is not permanent. It is disappearing, a little bit more each southern spring and summer season. At the present rate, a layer 3 m thick can be completely eroded away in a few tens of martian years. Since each layer is equivalent to about 1% of the mass of the present atmosphere (which is 95% carbon dioxide), if sufficient carbon dioxide is buried in the south polar cap, the mass of the atmosphere could double in a few hundred to a thousand Mars years. That could lead to profound changes in the environment. For example, it would change how much and where wind erosion would occur, and where and for how long liquid water could survive at or near the surface. It also means that Mars may have been very different in the recent past (perhaps only a few thousands of years ago). On today's Mars, the ice is eroding, but in the past that material had to have been deposited. The martian climate was probably colder, and, there was more carbon dioxide in the atmosphere. For some reason, large amounts of carbon dioxide froze at the south pole---one might say that there was a "Martian Ice Age"---and this freezing occurred on a time scale similar to that of the most recent Ice Age on Earth. Mars is changing, and it is changing on a time scale that we can measure and observe. If all of the carbon dioxide that is being released into the atmosphere from the south polar cap is not freezing out somewhere else, and if it is not being adsorbed into the martian soil, then it must be causing the atmospheric pressure to increase. If this is so, and if one were to assume that the entire known volume of the polar cap is made of carbon dioxide that sublimes at the same rate we see today, then it could increase the martian atmospheric pressure by as much as 10 times, to about 1/10th the density of Earth's atmosphere, in just the next few thousand years. Although this atmosphere would not be breathable, carbon dioxide is a "greenhouse gas" that would cause the global temperature to increase considerably and make it easier for liquid water to persist elsewhere on the planet. Perhaps, just perhaps, a thickening martian atmosphere would eventually make it easier for people to live on Mars. This new MGS MOC discovery is described in a paper published December 7, 2001, in the journal, Science. Read a more detailed discussion [ http://www.msss.com/mars_images/moc/CO2_Science_rel/malin_etal.html ] of these results (but less detailed than the Science article). Images Credit: NASA/JPL/Malin Space Science Systems |
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Sand Dunes of Nili Patera in
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| title |
Sand Dunes of Nili Patera in 3-D |
| Description |
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. Image Credit: NASA/JPL/Malin Space Science Systems |
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Sand Dunes of Nili Patera, S
…
| title |
Sand Dunes of Nili Patera, Syrtis Major |
| Description |
This dramatic image shows a field of dark sand dunes in the Nili Patera region of Syrtis Major. The shapes of these dunes indicate that wind has been steadily transporting the dark sand from the right/upper right toward the lower left. This picture was taken on the first day of the MGS Mapping Phase during the second week of March 1999. It shows an area 2.1 kilometers (1.3 miles) wide at the full commanded resolution of 3 meters per pixel. Illumination is from the upper left. Photo Credit: NASA/JPL/Malin Space Science Systems |
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"Not Vegetation!" Defrosting
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| title |
"Not Vegetation!" Defrosting Sand Dunes in Late Southern Winter |
| Description |
As winter gives way to spring in the martian southern hemisphere, the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) is observing the retreat of the south polar frost cap as sunlight falls upon it for the first time in several months. One of the most aesthetically-pleasing aspects of the spring defrosting process is the pattern that is created on the martian sand dune fields. Dunes are usually among the first surfaces to begin showing signs of change in late winter when temperatures are just beginning to creep above -125° C (-193° F, 148 K). The pattern of spots on the dunes in the above MOC picture was observed on June 8, 2001. The location of the dune field near 62°S, 155°W, is shown in the color context view, which was acquired at the same time. Dark spots and streaks on defrosting sand dunes were first observed by MOC in the northern hemisphere in 1998. Similar dark-spotted dunes in the southern hemisphere were described at a NASA/Mars Global Surveyor Space Science Update media briefing in 1999. Despite the "sensation" one gets when looking at pictures of spotted, defrosting martian dunes (i.e., the sensation that these images show some form of life, like vegetation, growing on Mars) these features are a normal, common manifestation of the springtime defrosting process on Mars. The ices involved--because of the low temperatures at these locations--are probably both frozen water and carbon dioxide, though it is unclear as to whether one type of ice dominates over the other in controlling the appearance and coalescence of the dark spots. It is known from the first martian year of MOC operations that by summer all of the frost--and thus all of the spots--on the dunes will be gone. North is up and sunlight illuminates the scene from the upper left in both pictures. The color context view covers an area approximately 115 km (72 miles) across, the high resolution image covers 3 km by 22 km (1.9 by 13.6 mi). Images Credit: NASA/JPL/Malin Space Science Systems |
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View of Argyre Basin from Te
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| title |
View of Argyre Basin from Test of Mars Color Image |
| Description |
, three views acquired by MARCI are compared to a color composite of two views acquired about four hours later by the wide-angle imager of Mars Orbiter Camera (MOC) on NASA's Mars Global Surveyor spacecraft. The MARCI imaging occurred during the morning on Mars, while the MOC observations were made at about 2 p.m. local solar time. The region of Mars imaged by MARCI was south of the Valles Marineris. It includes the Argyre Basin's interior plains, Argyre Planitia, and mountains forming the basin rim, Nereidum Montes to the northwest (middle of images) and Charitum Montes to the southeast (bottom of images). The color composite from MARCI differs from the MOC wide-angle color composite because, to create a color image with MOC data, camera-team members synthesize (fake) a green channel by adding the red and blue channels together and dividing by two. The slightly greenish tint of the MARCI image shows that the approximation used for MOC images underestimates the amount of green. The test image labeled 260 nm shows how the planet appears at an ultraviolet (UV) waveband of 260 nanometers, where ozone absorbs the UV light. Relatively darker areas in this band normally will indicate the presence of ozone, and relatively lighter areas will indicate the absence of ozone. Water vapor in Mars' atmosphere is in an inverse relationship with ozone, where there is more of one, there is less of the other. So, lighter areas in images can be used to track water vapor. The term "relatively" is used here because Mars itself is very dark in the UV owing to absorption of UV light by iron-bearing minerals, and sunlight is deficient in UV relative to visible light, so in general Mars will always look dark in the UV. A second UV band on MARCI (not shown in the figure above) at a longer wavelength allows these differences to be quantified. The MOC wide-angle image shows wispy, light water-ice clouds to the northwest of Argyre in the afternoon, but researchers cannot yet correlate these clouds with the UV information from MARCI, especially because the times of day are different. When in its final mapping orbit, Mars Reconnaissance Orbiter will view the same area as Mars Global Surveyor separated by only one hour, and such correlations will be much more direct. For more details of how MARCI images are acquired and processed, see the companion release, MARCI2-3 [ http://www.msss.com/others/marci_release/marci_detail/index.html ], and be certain to examine the 15.6 Mbyte animated GIF movie, . The pictures shown here are the first views of Mars acquired by the Mars Color Imager on Mars Reconnaissance Orbiter. This is a re-flight of a similar instrument that was aboard the Mars Climate Orbiter, which was lost in September 1999 during its orbit insertion activity. In the primary science phase of the Mars Reconnaissance Orbiter, MARCI will routinely acquire daily global maps of the planet. These data will be used to help track storms, monitor clouds and water vapor, and track seasonal changes in surface albedo (bright and dark) patterns and the polar caps. Credit: NASA/JPL/MSSS, The Mars Color Imager (MARCI) camera on NASA's Mars Reconnaissance Orbiter acquired a seven-band color, wide-angle view of Mars on March 24, 2006, as part of a checkout of the orbiter's payload. This image shows a color composite made from the MARCI red, green, and blue bands. The view looks northward and includes the large Argyre Basin in Mars' southern hemisphere. One use of the test imaging is an opportunity to fine-tune calibrations used for processing the separate bands into "true" color -- as it would appear to a human eye looking down from orbit. Further calibration will be needed. Regular use of MARCI and the other science instruments on Mars Reconnaissance Orbiter will begin in autumn 2006, after the spacecraft's orbit has been reshaped to a nearly circular, low-altitude path.*Full Res JPG (236 kB)* The March 24 test produced images from each color band. Illustrated here are some of these test images. In figure 1 [ http://photojournal.jpl.nasa.gov/catalog/PIA08067 ] |
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Olympus Mons, 1998
| title |
Olympus Mons, 1998 |
| Description |
Olympus Mons is a mountain of mystery. Taller than three Mount Everests and about as wide as the entire Hawaiian Island chain, this giant volcano is nearly as flat as a pancake. That is, its flanks typically only slope 2° to 5°. The Mars Orbiter Camera (MOC) obtained this spectacular wide-angle view of Olympus Mons on Mars Global Surveyor's 263rd orbit, around 10:40 p.m. PDT on April 25, 1998. In the view presented here, north is to the left and east is up. The spacecraft was traveling from north to south (left to right). Although the camera looks straight down (towards the nadir) and cannot be pointed to the side, the wide angle camera has such a large field of view (it sees from horizon to horizon) that, in effect, it provides side looking views. Unlike some other MOC images, that have had to be warped to provide a view as if seen from a certain direction and altitude, this image shows what the camera saw without additional processing. It is easy to imagine that you are looking out a window at the surface of Mars from about 900 km (560 miles) up. The image was taken on a cool, crisp winter morning. The west side of the volcano (lower portion of view, above) was clear and details on the surface appear very sharp. The skies above the plains to the east of Olympus Mons (upper portion of view) were cloudy. Clouds were lapping against the lower east flanks of this 26 kilometers (16 miles) high volcano, but the summit skies were clear. When Mars Global Surveyor attains its Mapping Orbit in March 1999, the MOC wide angle camera system will be used to make daily, global maps of martian clouds and weather systems. The wide angle images will resemble weather satellite pictures of Earth, and will help the Mars science teams plan their observations and test computer-driven Mars weather prediction models. 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. Photo Credit: NASA/JPL/Malin Space Science Systems |
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Apollinaris Patera
| title |
Apollinaris Patera |
| Description |
This month (April 1999), the Mars Global Surveyor Mars Orbiter Camera (MOC) passed over the Apollinaris Patera volcano and captured a patch of bright clouds hanging over its summit in the early martian afternoon. This ancient volcano is located near the equator and--based on observations from the 1970s Viking Orbiters--is thought to be as much as 5 kilometers (3 miles) high. The caldera--the semi-circular crater at the volcano summit--is about 80 kilometers (50 miles) across. The color in this picture was derived from the MOC red and blue wide angle camera systems and does not represent true color as it would appear to the human eye (that is, if a human were in a position to be orbiting around the red planet). 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. Photo Credit: NASA/JPL/Malin Space Science Systems |
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East Gorgonum Crater
| title |
East Gorgonum Crater |
| Description |
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 (lower left) is a composite of three different high resolution MOC views obtained in 1999 and 2000. The second picture (lower 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 37.4°S, 168.0°W. The composite view in the lower 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. Photo Credit: NASA/JPL/Malin Space Science Systems |
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Martian North Polar Cap on S
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PIA01471
Sol (our sun)
Mars Orbiter Camera
| Title |
Martian North Polar Cap on September 12, 1998 (color) |
| Original Caption Released with Image |
Mars Global Surveyor's Mars Orbiter Camera obtained its last SPO-2 images of Mars on September 12, 1998. SPO-2, or "Science Phasing Orbit-2", took place between early June and mid-September 1998. Shown above are MOC wide angle (red and blue band) images of the martian north polar region obtained around 3:15 a.m. PDT on September 12, 1998. This color composite was made using red and blue wide angle MOC images 55001 and 55002--these were the last pictures taken of the planet until the camera resumes its work in late-March 1999. The north polar layered deposits, a terrain believed composed of ice and dust deposited over millions of years, dominates this view. The swirled pattern in the images above are channels eroded into this deposit. The pattern is accentuated by the illumination and seasonal frost differences that arise on sun-facing slopes during the summer. The permanent portion of the north polar cap covers most of the region with a layer of ice of unknown thickness. At the time this picture was obtained, the martian northern hemisphere was in the midst of the early Spring season. The margin of the seasonal carbon dioxide frost cap was at about 67° N, so the ground throughout this image is covered by frost. The frost appears pink rather than white, this may result from textural changes in the frost as it sublimes or because the frost is contaminated by a small amount of reddish martian dust. Please note that these pictures have not been "calibrated" and so the colors are not necessarily accurately portrayed. In addition to the north polar cap, the pictures also show some clouds (bluish-white wisps). Some of the clouds on the right side of the images are long, linear features that cast similar long, dark shadows on the ground beneath them. When the MOC resumes imaging of Mars in March 1999, summer will have arrived in the north polar regions and the area surrounding the permanent polar cap will appear much darker than it does here. The dark features surrounding the cap are sand dunes, and these are expected to darken over the next several months as seasonal ice sublimes and is removed from the 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. |
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Mars Boulders: On a Hill in
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PIA01500
Sol (our sun)
Mars Orbiter Camera
| Title |
Mars Boulders: On a Hill in Utopia Planitia |
| Original Caption Released with Image |
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.(CLICK HERE for a context image). North is approximately up, illumination is from the 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. |
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Mars Boulders: On a Hill in
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PIA01500
Sol (our sun)
Mars Orbiter Camera
| Title |
Mars Boulders: On a Hill in Utopia Planitia |
| Original Caption Released with Image |
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.(CLICK HERE for a context image). North is approximately up, illumination is from the 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. |
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Early MOC Global Color Mosai
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PIA01673
Sol (our sun)
Mars Orbiter Camera
| Title |
Early MOC Global Color Mosaics |
| Original Caption Released with Image |
These two images are synthetic views of Mars made by combining Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) wide angle images from several orbits during the first week of March 1999--during MOC's focus and calibration testing period. The blue and red lines are the edges of the original pictures. Views such as these will be used throughout the MGS Mapping Mission to characterize the changing weather patterns on Mars. Right now, it is northern hemisphere summer on Mars, and the north polar ice cap can be seen at the top of each image. In the view on the left, thick blue-white afternoon water ice clouds can be seen surrounding and obscuring the northern-most of the large volcanoes of the Tharsis Montes region (left), and clouds can also be seen over Lunae Planum (center) and Chryse Planitia (center right). In the right image, faint clouds are seen over Arabia (center left bright region) with somewhat thicker clouds seen over Syrtis Major (dark, triangular region toward the right). Very thick southern winter clouds can be seen "ponded" within the Hellas Basin near the bottom of the frame. 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. |
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Northern Plains Textures Vis
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PIA01697
Sol (our sun)
Mars Orbiter Camera
| Title |
Northern Plains Textures Visible Near the Terminator |
| Original Caption Released with Image |
Each day, Mars Global Surveyor makes 12 orbits around the red planet. On each orbit at the present time (April 1999), the spacecraft passes from daylight into night somewhere over the northern plains of Mars, and re-emerges into daylight over the southern cratered highlands. The illumination conditions near the martian terminator--the line between night and day--are perfect for observing surface texture and topography. This picture shows a common, rough and bumpy texture that MOC has revealed on the northern plains of Mars. Note the eroded impact crater at the bottom right--small black dots along its rim are interpreted to be boulders. This image covers an area 3 kilometers (1.9 miles) wide by 8 kilometers (5 miles) long and is illuminated by the sun shining low from the northeastern horizon(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. |
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Mariner 4 Meets Mars Global
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PIA01685
Sol (our sun)
Mars Orbiter Camera
| Title |
Mariner 4 Meets Mars Global Surveyor--Mariner Crater 1965 and 1999 |
| Original Caption Released with Image |
Mars exploration in the last half of the 20th Century comes full circle with a modern view of Mariner Crater obtained by the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) in early March 1999. Mariner 4 was the first spacecraft to reach the red planet and take close-up pictures that revealed its ancient, cratered surface. The picture on the left, above, is the 11th image taken by Mariner 4 during its July 1965 flyby. The center of the Mariner 4 image is dominated by a crater that is about 155 kilometers (96 miles) in diameter and located at 32°S latitude and 164°W longitude. The crater was named "Mariner" in 1967 by the International Astronomical Union in honor of its discovery by Mariner 4. The white arrow indicates the location of the new MGS MOC image. The picture on the right represents an improvement in resolution of almost a factor of 400. It shows a view of a tiny portion of the southeastern floor of Mariner Crater, as it appeared to the MGS MOC in 1999. In 1965, it was a surprise to find that the martian surface is pocked with craters. In 1999, using the MGS MOC, we now have the ability to see objects the size of automobiles on the martian surface. This view of the Mariner Crater floor has a spatial resolution of 1.5 meters(5 feet) per pixel and covers an area only 1.5 km (0.9 mi) wide by 2.2 km (1.4 mi)long. Illumination is from the upper left in both the Mariner and MGS images. For a mercator-projected Viking 1 Orbiter view of this crater (obtained in 1978)click here. 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. |
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High Resolution View of Nort
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PIA01677
Sol (our sun)
Mars Orbiter Camera
| Title |
High Resolution View of Northern Plains Surface |
| Original Caption Released with Image |
Until now, the vast northern plains of Mars have largely eluded the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) because these plains were obscured by winter and springtime clouds during most of the 1997 and 1998 Aerobraking and Science Phasing portions of the MGS Mission. However, now in March 1999 it is summertime in the northern hemisphere of Mars, and the northern plains are clearly in view. This image was taken at a resolution of 3 meters (10 feet) per pixel in order to characterize the nature of these plains. The image is located near Lomonosov Crater on the Vastitas Borealis plain. The image shows a patterned surface with two distinct rings that are suspected to be the locations of buried impact craters. The larger such ring (right) has dark spots clustered in several patches along its margins--these are fields boulders and rocks. The image covers an area 3 kilometers (1.9 miles) across and is illuminated from the lower 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. |
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Boulder Tracks on Schiaparel
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PIA01680
Sol (our sun)
Mars Orbiter Camera
| Title |
Boulder Tracks on Schiaparelli Basin South Wall |
| Original Caption Released with Image |
The above Mars Orbiter Camera (MOC) image shows a portion of the slope just inside the south rim of the approximately 400 kilometer-(250 mile)-wide Schiaparelli Basin near the martian equator. The large white arrow points to a steep cliff exposure of dark-toned rock. The small white arrow points to one of several ~18 meter (59 feet) diameter boulders that apparently broke off the steep, dark cliff and rolled down the slope to the basin floor. Each boulder left behind a trail on the relatively soft, dusty slope. In addition, some of the boulders exhibit a bright wind streak pointing toward the lower left/center, indicating that these boulders have been sitting there long enough to influence local wind distribution of sediment. Before the Mars Global Surveyor (MGS) mission, boulder tracks such as these had never been seen on Mars before, but in the 1960s and 1970s several examples on the Moon and Earth were documented. The picture shown here covers an area approximately 2.8 kilometers (1.7 miles) by 4.4 kilometers (2.7 miles). Illumination is from the lower left. The picture was acquired in January 1998 during the MGS Aerobrake-1 Orbits imaging campaign, and was presented at the 30th Lunar and Planetary Science Conference in Houston, Texas, March 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. |
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Mars Surfaces at 15.6°N Lati
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PIA01672
Sol (our sun)
Mars Orbiter Camera
| Title |
Mars Surfaces at 15.6°N Latitude, March 1999 |
| Original Caption Released with Image |
This set of 12 images was obtained during the period of Mars Orbiter Camera(MOC) focus tests and calibrations that executed in the first week of March 1999. Each picture was taken near 15.6°N latitude, which at this time was the sub-Earth point--the latitude at which Earth would be seen directly overhead if viewed from the ground. These pictures were obtained to provide a direct link between simultaneous Earth- and space-based telescope observations and the MOC. Each picture is shown at the full commanded resolution of 12 meters (39 feet) per pixel, and each covers an area 3 by 3 kilometers (1.9 miles) in size with illumination from the upper left. Typically, images that will be obtained by MOC during the Mapping Phase of the Mars Global Surveyor mission will have resolutions of 1.5 meters (5 feet) per pixel--a factor of 8 improvement over the pictures shown here. 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. |
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East Tithonium Chasma Wall,
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PIA01696
Sol (our sun)
Mars Orbiter Camera
| Title |
East Tithonium Chasma Wall, Valles Marineris |
| Original Caption Released with Image |
Layers of wall rock, windblown drifts, and landslide deposits can be seen in this new view of the wall of Tithonium Chasma in the Valles Marineris trough system. The picture covers an area 3 kilometers (1.9 miles) wide by about 11 kilometers (6.8 miles) long and is illuminated from the lower right. The Mars Orbiter Camera on board the Mars Global Surveyor spacecraft acquired this dramatic picture in early April 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. |
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