Mission Mars Global Surveyor - 2

<h1>PIA00606: Mars Global Surveyor Approach Image</h1><div class="PIA00606" lang="en" style="width:512px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;">This image is the first view of Mars taken by the Mars Global Surveyor Orbiter Camera (MOC). It was acquired the afternoon of July 2, 1997 when the MGS spacecraft was 17.2 million kilometers (10.7 million miles) and 72 days from encounter. At this distance, the MOC's resolution is about 64 km per picture element, and the 6800 km (4200 mile) diameter planet is 105 pixels across. The observation was designed to show the Mars Pathfinder landing site at 19.4 N, 33.1 W approximately 48 hours prior to landing. The image shows the north polar cap of Mars at the top of the image, the dark feature Acidalia Planitia in the center with the brighter Chryse plain immediately beneath it, and the highland areas along the Martian equator including the canyons of the Valles Marineris (which are bright in this image owing to atmospheric dust). The dark features Terra Meridiani and Terra Sabaea can be seen at the 4 o`clock position, and the south polar hood (atmospheric fog and hazes) can be seen at the bottom of the image. Launched on November 7, 1996, Mars Global Surveyor will enter Mars orbit on Thursday, September 11 shortly after 6:00 PM PDT. After Mars Orbit Insertion, the spacecraft will use atmospheric drag to reduce the size of its orbit, achieving a circular orbit only 400 km (248 mi) above the surface in early March 1998, when mapping operations will begin.<p>The Mars Global Surveyor is operated by the Mars Surveyor Operations Project managed for NASA by the Jet Propulsion Laboratory, Pasadena CA. The Mars Orbiter Camera is a duplicate of one of the six instruments originally developed for the Mars Observer mission. It was built and is operated under contract to JPL by an industry/university team led by Malin Space Science Systems, San Diego, CA.<br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA00606" onclick="window.open(this.href); return false;" title="Voir l'image PIA00606: Mars Global Surveyor Approach Image sur le site de la NASA">Voir l'image PIA00606: Mars Global Surveyor Approach Image sur le site de la NASA.</a></div>
PIA00606: Mars Global Surveyor Approach Image
<h1>PIA00607: Hubble and Mars Global Surveyor Views of Dust Storm on Mars</h1><div class="PIA00607" lang="en" style="width:640px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;">A comparison of images taken by the Hubble Space Telescope Wide Field/Planetary Camera (HST/WFPC) and the Mars Global Surveyor Orbiter Camera (MGS/MOC) shows the progress of a regional dust storm within the Valles Marineris canyons on Mars. The first HST image (left), taken in mid-May, shows no dust within the canyons. The most recent HST image (center), taken on 27 June in support of the Mars Pathfinder landing activities, shows a dust storm filling part of the canyon system and extending into the chaotic terrains at the eastern end of the canyons. The MGS/MOC image (right), acquired on July 2, shows that bright dust continues to fill the valleys. However, it does not appear to have moved significantly north of the previously observed position, suggesting that the storm remains confined to the canyon region, and does not appear to directly threaten the Pathfinder landing site (small black circle).<p>The HST images shown here have been reduced in scale to match that of the MGS/MOC image. Although the HST is 10 times farther from Mars than MGS, its images are sharper because its resolving power is 15 times better than the MOC, and the light gathering area is almost 50 times greater. However, MGS is presently 45,000 times farther from Mars than it will be when the MOC begins its primary photography mission. At 400 km above the martian surface, the MOC wide angle camera will collect daily images at a resolution of 7.5 km/pixel, compared to HST's best of about 20 km/pixel. The narrow angle camera will observe portions of Mars at better than 1.5 m/pixel.<p>The Mars Global Surveyor is operated by the Mars Surveyor Operations Project managed for NASA by the Jet Propulsion Laboratory, Pasadena CA. The Mars Orbiter Camera is a duplicate of one of the six instruments originally developed for the Mars Observer mission. It was built and is operated under contract to JPL by an industry/university team led by Malin Space Science Systems, San Diego, CA.<br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA00607" onclick="window.open(this.href); return false;" title="Voir l'image PIA00607: Hubble and Mars Global Surveyor Views of Dust Storm on Mars sur le site de la NASA">Voir l'image PIA00607: Hubble and Mars Global Surveyor Views of Dust Storm on Mars sur le site de la NASA.</a></div>
PIA00607: Hubble and Mars Global Surveyor Views of Dust Storm on Mars
<h1>PIA01435: Winter Morning in Northern Tharsis</h1><div class="PIA01435" lang="en" style="width:689px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;">Mars Global Surveyor's camera, MOC, provided this hemispheric view of the northern Tharsis region on June 1, 1998. This picture shows the giant volcano, Olympus Mons, and one of the Tharsis Montes volcanoes, Ascraeus Mons. Another volcano, Alba Patera, is lurking under the haze and clouds at the top of the image. Olympus Mons is about 550 kilometers (340 miles) wide.<p>MGS is now in a "morning" orbit (when it arrived at Mars in September 1997, it was inserted into a "late afternoon" orbit). The orbit will continue to change, about one hour a month, until aerobraking into a circular orbit is complete about seven months from now. When this picture was taken, the local time on the ground beneath the spacecraft was about 9:30 a.m. The terminator-- the line that divides night and day-- was located west of Olympus Mons (left part of the image). It is winter in the northern hemisphere of Mars, and the high latitudes (i.e., north of Olympus Mons in this picture) exhibit clouds and haze. These clouds most likely contain water ice.<p>MOC images 33901 (the red wide angle image) and 33902 (the blue wide angle image) were obtained on Mars Global Surveyor's 339th orbit about the planet. The pictures were taken around 7:37 p.m. PDT on June 1, 1998.<p><p>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.<br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA01435" onclick="window.open(this.href); return false;" title="Voir l'image PIA01435: Winter Morning in Northern Tharsis sur le site de la NASA">Voir l'image PIA01435: Winter Morning in Northern Tharsis sur le site de la NASA.</a></div>
PIA01435: Winter Morning in Northern Tharsis
<h1>PIA01471: Martian North Polar Cap on September 12, 1998 (color)</h1><div class="PIA01471" lang="en" style="width:800px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>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.<p>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.<p>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.<p>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.<p>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.<p><p>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.<br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA01471" onclick="window.open(this.href); return false;" title="Voir l'image PIA01471: Martian North Polar Cap on September 12, 1998 (color) sur le site de la NASA">Voir l'image PIA01471: Martian North Polar Cap on September 12, 1998 (color) sur le site de la NASA.</a></div>
PIA01471: Martian North Polar Cap on September 12, 1998 (color)
<h1>PIA01673: Early MOC Global Color Mosaics</h1><div class="PIA01673" lang="en" style="width:800px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>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.</p><p>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).</p><p>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.</p><p>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.</p><br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA01673" onclick="window.open(this.href); return false;" title="Voir l'image PIA01673: Early MOC Global Color Mosaics sur le site de la NASA">Voir l'image PIA01673: Early MOC Global Color Mosaics sur le site de la NASA.</a></div>
PIA01673: Early MOC Global Color Mosaics
<h1>PIA01888: Mars at Ls 137°</h1><div class="PIA01888" lang="en" style="width:800px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>13 November 2006<br />These images capture what Mars typically looks like in mid-afternoon at Ls 137°. In other words, with the exception of occasional differences in weather and polar frost patterns, this is what the red planet looks like this month (November 2006). <p></p>Six views are shown, including the two polar regions. These are composites of 24-26 Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) daily global mapping images acquired at red and blue wavelengths. The 'hole' over the south pole is an area where no images were obtained, because this polar region is enveloped in wintertime darkness. <p></p>Presently, it is summer in the northern hemisphere and winter in the southern hemisphere. Ls, solar longitude, is a measure of the time of year on Mars. Mars travels 360° around the Sun in 1 Mars year. The year begins at Ls 0°, the start of northern spring and southern autumn. Northern summer/southern winter begins at Ls 90°, northern autumn/southern spring start at Ls 180°, and northern winter/southern summer begin at Ls 270°. <p></p>Ls 137° occurs in the middle of this month (November 2006). The pictures show how Mars appeared to the MOC wide angle cameras at a previous Ls 137° in March 2001. The six views are centered on the Tharsis region (upper left), Acidalia and Mare Eyrthraeum (upper right), Syrtis Major and Hellas (middle left), Elysium and Mare Cimmeria (middle right), the north pole (lower left), and the south pole (lower right).</p><br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA01888" onclick="window.open(this.href); return false;" title="Voir l'image PIA01888: Mars at Ls 137° sur le site de la NASA">Voir l'image PIA01888: Mars at Ls 137° sur le site de la NASA.</a></div>
PIA01888: Mars at Ls 137°
<h1>PIA02000: Acidalia and Chryse Plains, Mars</h1><div class="PIA02000" lang="en" style="width:800px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>Somewhere down there sits the Mars Pathfinder lander and Sojourner rover. This Mars Global Surveyor Mars Orbiter Camera view of the red planet shows the region that includes Ares Vallis and the Chryse Plains upon which both Mars Pathfinder and the Viking 1 landed in 1997 and 1976, respectively. Acidalia Planitia is the dark surface that dominates the center left. The Pathfinder site is immediately south of Acidalia, just left of center in this view. Also shown--the north polar cap is at the top, and Arabia Terra and Sinus Meridiani are to the right. The bluish-white features are clouds. This is a color composite of 9 red and 9 blue image strips taken by the Mars Global Surveyor Mars Orbiter Camera on 9 successive orbits from pole-to-pole during the calibration phase of the mission in March 1999. The color is computer-enhanced and is not shown as it would actually appear to the human eye.</p><p>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.</p><br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA02000" onclick="window.open(this.href); return false;" title="Voir l'image PIA02000: Acidalia and Chryse Plains, Mars sur le site de la NASA">Voir l'image PIA02000: Acidalia and Chryse Plains, Mars sur le site de la NASA.</a></div>
PIA02000: Acidalia and Chryse Plains, Mars
<h1>PIA02004: Syrtis Major and Arabia Terra, Mars</h1><div class="PIA02004" lang="en" style="width:800px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>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.</p><p>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.</p><br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA02004" onclick="window.open(this.href); return false;" title="Voir l'image PIA02004: Syrtis Major and Arabia Terra, Mars sur le site de la NASA">Voir l'image PIA02004: Syrtis Major and Arabia Terra, Mars sur le site de la NASA.</a></div>
PIA02004: Syrtis Major and Arabia Terra, Mars
<h1>PIA02005: Tharsis Volcanoes and Valles Marineris, Mars</h1><div class="PIA02005" lang="en" style="width:800px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>It is northern summer on Mars and clouds are very common over the famous Tharsis volcanoes during the afternoon. At the far left, a white patchy cloud denotes the location of Olympus Mons. Ascraeus Mons is under the brightest cloud toward the center left, but the volcanoes Pavonis Mons and Arsia Mons (toward lower left below Ascraeus Mons) have much less cloud cover. The patch of clouds toward the upper left mark the location of the Alba Patera volcano. The Valles Marineris trough system--so long that it would stretch across North America--is seen in the lower third of this picture. This is a color composite of 9 red and 9 blue image strips taken by the Mars Global Surveyor Mars Orbiter Camera on 9 successive orbits from pole-to-pole during the calibration phase of the mission in March 1999. The color is computer-enhanced and is not shown as it would actually appear to the human eye.</p><p>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.</p><br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA02005" onclick="window.open(this.href); return false;" title="Voir l'image PIA02005: Tharsis Volcanoes and Valles Marineris, Mars sur le site de la NASA">Voir l'image PIA02005: Tharsis Volcanoes and Valles Marineris, Mars sur le site de la NASA.</a></div>
PIA02005: Tharsis Volcanoes and Valles Marineris, Mars
<h1>PIA02653: Mars Daily Global Image from April 1999</h1><div class="PIA02653" lang="en" style="width:800px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>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 <a href="/catalog/PIA02066">PIA02066</a> onto a sphere. The center of this newly projected sphere is located at 15degrees 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.<p>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.<br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA02653" onclick="window.open(this.href); return false;" title="Voir l'image PIA02653: Mars Daily Global Image from April 1999 sur le site de la NASA">Voir l'image PIA02653: Mars Daily Global Image from April 1999 sur le site de la NASA.</a></div>
PIA02653: Mars Daily Global Image from April 1999
<h1>PIA03170: The 2001 Great Dust Storms - Hellas/Syrtis Major</h1><div class="PIA03170" lang="en" style="width:800px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>Although dust storms occur year-round on Mars, they often occur in greater numbers during certain seasons. In particular, it has long been known from Earth-based telescopic observations that the largest, global dust events(those that enshroud the entire planet) occur during the southern spring and summer. As the Mars Global Surveyor (MGS) mission began to monitor this period for the second time, particular attention was paid to local and regional dust storms in anticipation of capturing--for the first time--high spatial-and time-resolution observations of the start of a "global" storm.<p>Throughout the month of June 2001, the MGS Mars Orbiter Camera (MOC)routinely accumulated low resolution (7.5 km/pixel) global maps of Marson an orbit-by-orbit basis. A moderately large number of local dust storms were noted, especially along the retreating margin of the seasonal south polar CO2 frost cap and around the large and deep Hellas impact basin that dominates the southern, eastern highlands. On June 21, an otherwise undistinguished small dust storm surged into the basin from the southwest. When viewed 24 hours later, the storm had circulated clockwise about 1/3of the circumference of Hellas, indicating relatively high winds. For the next three days, this storm brewed north of Hellas and east towards Hesperia, but didn't cross the equator. Then, sometime between 2 PM local Mars time on June 25 and 2 PM local Mars time on June 26, the storm exploded north across the equator, and in less than 24 hours thereafter, dust was being raised from separate locations in Arabia, Nilosyrtis, and Hesperia, thousands of kilometers away from Hellas. This was the start of the long-anticipated global dust event.<p>Over the following week, dust injected high into the stratosphere during the initial Hellas and Hesperia storms drifted eastward, carried by the prevailing south circumpolar jet stream. Beneath this "veil" of dust, an intense wind front moved across Mars, setting up conditions for many other local and regional dust storms. By July 4, a large regional storm was raging between Daedalia Planitia south of the Tharsis volcanoes and Syria Planum (just south of Labyrinthus Noctis, see <a href="/catalog/PIA03171">PIA03171</a>). Another storm was raising plumes of dust in north central Noachis/southwestern Meridiani. Plumes were rising in Hesperia but not Hellas.<p>Throughout July and August, MOC observations revealed a general pattern of regional storm centers beneath an ever-spreading veil of stratospheric dust. The Daedalia/Claritas/Syria storm created dust plumes on over 90 consecutive days (see <a href="/catalog/PIA03172">PIA03172</a>).<p>Previous views and perceptions of global dust events had noted regional brightenings within the overall pall of what was called a "global duststorm." From our new observations, we know that at least this global dust "storm" was really a set of storms, somehow triggered to occur at the same time. We also know that dust was not raised from everywhere on the surface during this global event, but rather from discrete, long-lived centers of activity. We saw, for the first time, rapid, cross-equatorial flow of dust-raising winds.<p>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.<br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA03170" onclick="window.open(this.href); return false;" title="Voir l'image PIA03170: The 2001 Great Dust Storms - Hellas/Syrtis Major sur le site de la NASA">Voir l'image PIA03170: The 2001 Great Dust Storms - Hellas/Syrtis Major sur le site de la NASA.</a></div>
PIA03170: The 2001 Great Dust Storms - Hellas/Syrtis Major
<h1>PIA03171: The 2001 Great Dust Storms - Tharsis</h1><div class="PIA03171" lang="en" style="width:800px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>Although dust storms occur year-round on Mars, they often occur in greater numbers during certain seasons. In particular, it has long been known from Earth-based telescopic observations that the largest, global dust events(those that enshroud the entire planet) occur during the southern spring and summer. As the Mars Global Surveyor (MGS) mission began to monitor this period for the second time, particular attention was paid to local and regional dust storms in anticipation of capturing--for the first time--high spatial-and time-resolution observations of the start of a "global" storm.<p>Throughout the month of June 2001, the MGS Mars Orbiter Camera (MOC)routinely accumulated low resolution (7.5 km/pixel) global maps of Marson an orbit-by-orbit basis. A moderately large number of local dust storms were noted, especially along the retreating margin of the seasonal south polar CO2 frost cap and around the large and deep Hellas impact basin that dominates the southern, eastern highlands. On June 21, an otherwise undistinguished small dust storm surged into the basin from the southwest. When viewed 24 hours later, the storm had circulated clockwise about 1/3of the circumference of Hellas, indicating relatively high winds. For the next three days, this storm brewed north of Hellas and east towards Hesperia, but didn't cross the equator(see <a href="/catalog/PIA03170">PIA03170</a>). Then, sometime between 2 PM local Mars time on June 25 and 2 PM local Mars time on June 26, the storm exploded north across the equator, and in less than 24 hours thereafter, dust was being raised from separate locations in Arabia, Nilosyrtis, and Hesperia, thousands of kilometers away from Hellas. This was the start of the long-anticipated global dust event.<p>Over the following week, dust injected high into the stratosphere during the initial Hellas and Hesperia storms drifted eastward, carried by the prevailing south circumpolar jet stream. Beneath this "veil" of dust, an intense wind front moved across Mars, setting up conditions for many other local and regional dust storms. By July 4, a large regional storm was raging between Daedalia Planitia south of the Tharsis volcanoes and Syria Planum (just south of Labyrinthus Noctis). Another storm was raising plumes of dust in north central Noachis/southwestern Meridiani. Plumes were rising in Hesperia but not Hellas.<p>Throughout July and August, MOC observations revealed a general pattern of regional storm centers beneath an ever-spreading veil of stratospheric dust. The Daedalia/Claritas/Syria storm created dust plumes on over 90 consecutive days (see <a href="/catalog/PIA03172">PIA03172</a>).<p>Previous views and perceptions of global dust events had noted regional brightenings within the overall pall of what was called a "global duststorm." From our new observations, we know that at least this global dust "storm" was really a set of storms, somehow triggered to occur at the same time. We also know that dust was not raised from everywhere on the surface during this global event, but rather from discrete, long-lived centers of activity. We saw, for the first time, rapid, cross-equatorial flow of dust-raising winds.<p>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.<br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA03171" onclick="window.open(this.href); return false;" title="Voir l'image PIA03171: The 2001 Great Dust Storms - Tharsis sur le site de la NASA">Voir l'image PIA03171: The 2001 Great Dust Storms - Tharsis sur le site de la NASA.</a></div>
PIA03171: The 2001 Great Dust Storms - Tharsis
<h1>PIA03229: Mars Opposition and Equinox</h1><div class="PIA03229" lang="en" style="width:800px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>Prior to the Mariner 4 flyby in 1965, all we knew about Mars came from Earth-based telescopic observations. At best, Mars is a challenging object to observe, due to its small size, low contrast, and turbulence in Earth's atmosphere. The best times to see the planet are around its closest approaches to Earth, which occur near "opposition," when the two planets are roughly in a line on one side of the Sun. This occurs about every 26 months, when Mars can appear to grow (in the night sky) to as large as about 20 arc-seconds in size. (20 arc-seconds is about the apparent size of a dime seen from 190 meters, or about the length of two football fields, away; it is about the size of a crater 40 kilometers (25 miles) in diameter on the Moon.)</p><p>In 2001, Mars is at opposition on June 13-14 and makes its closest approach to Earth on June 21, when it is about 67 million kilometers (~42 million miles) away and subtends 20.8 arc-seconds in the sky. For observers in the northern hemisphere, it can be seen as a bright (magnitude -2) red object, low in the southern sky near the constellation Scorpius, in the evening. Southern hemisphere observers have a better view, as Mars is higher in the sky from that vantage. </p><p>Not only is Mars at opposition June 13-14, 2001, and making its closest approach to Earth since 1988 on June 21st, on June 17-18 Mars will be at equinox, with the southern hemisphere turning to spring and the northern hemisphere begins autumn. The diagrams below illustrate the opposition and equinox configurations of Mars.</p><p>The Image above is one of a series of simulated views of Mars as it would be seen from the Mars Global Surveyor spacecraft. To view the rest of these images please go to the <a href="http://www.msss.com/mars_images/moc/opposition_6_2001/index.html" class="external free" target="wpext">June 2001: Mars Opposition and Equinox</a> page at the Malin Space Science Systems web site.</p><br>Animation of simulated Earth-based views of Mars.<br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA03229" onclick="window.open(this.href); return false;" title="Voir l'image PIA03229: Mars Opposition and Equinox sur le site de la NASA">Voir l'image PIA03229: Mars Opposition and Equinox sur le site de la NASA.</a></div>
PIA03229: Mars Opposition and Equinox
<h1>PIA03755: Global Views of Mars in late Northern Summer</h1><div class="PIA03755" lang="en" style="width:800px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;">Mars Global Surveyor (MGS) orbits around the red planet 12 times a day. Each orbit goes from pole to pole. Over the course of a single day, the wide angle cameras of the Mars Orbiter Camera (MOC) system take 24 pictures--12 red and 12 blue--that are assembled to create a daily global map. Such global views are used to monitor the martian weather and observe changes in the patterns of frost and dust distribution on the surface. These two pictures are examples of what Mars looks like in late northern summer, which is also late southern winter. At this time of year, the south polar cap (bottom, white feature in each image) is very large, extending from the south pole northward to 60°S. Also at this time of year, clouds of water ice crystals are common over the four largest volcanoes in Tharsis. The picture on the right shows Tharsis, with the four volcanoes forming a triangle resembling the pattern of holes on a bowling ball. The image on the left is centered on Syrtis Major, a dark, windswept volcanic plain so large that it has been known to science since the first telescopes were turned toward Mars in the 1600s. The elliptical bright feature at lower-center in the left image is the Hellas Basin, the largest unequivocal impact basin (formed by an asteroid or comet) on the planet. Hellas is approximately 2200 km (1,370 mi) across.<br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA03755" onclick="window.open(this.href); return false;" title="Voir l'image PIA03755: Global Views of Mars in late Northern Summer sur le site de la NASA">Voir l'image PIA03755: Global Views of Mars in late Northern Summer sur le site de la NASA.</a></div>
PIA03755: Global Views of Mars in late Northern Summer
<h1>PIA03780: Nirgal Vallis and its Windblown Dunes</h1><div class="PIA03780" lang="en" style="width:800px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;">The wide angle cameras of the Mars Orbiter Camera (MOC) system onboard Mars Global Surveyor (MGS) are used every day to gather a global view of changes occurring in martian weather and surface frost patterns. Late in June 2001, as southern winter transitioned to spring, dust storm activity began to pick up as cold air from the south polar cap moved northward toward the warmer air at the martian equator. By early July, dust storms had popped up all over the planet, particularly throughout the southern hemisphere and in the Elysium/Amazonis regions of the northern hemisphere. Soon, the entire planet--except the south polar cap--was enshrouded in dust. Similar storms have occurred before. For example, the planet was obscured by dust when the Mariner 9, Mars 2, and Mars 3 spacecraft reached the planet in late 1971. The MGS MOC images showed the evolution of the 2001 great dust storm period. There was never a time when the entire planet was in the midst of a single storm. Several large storms would occur at the same time, and dust was kicked high into the atmosphere to cause much of the rest of the planet to be obscured. The dust storms largely subsided by late September 2001, but the atmosphere remained hazy into November of that year. The two pictures shown here come from the E05 (June 2001) and E06 (July 2001) subphases of the MGS MOC Extended Mission. The view from June shows the Tharsis volcanic region (left), Valles Marineris chasms (right) and the late winter south polar cap (bottom). The view from July shows the same regions, but most of the details are hidden by dust storms and haze.<br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA03780" onclick="window.open(this.href); return false;" title="Voir l'image PIA03780: Nirgal Vallis and its Windblown Dunes sur le site de la NASA">Voir l'image PIA03780: Nirgal Vallis and its Windblown Dunes sur le site de la NASA.</a></div>
PIA03780: Nirgal Vallis and its Windblown Dunes
<h1>PIA04050: Springtime North Polar Dust Storms</h1><div class="PIA04050" lang="en" style="width:800px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;">MGS MOC Release No. MOC2-321, 12 December 2002<p>As on the Earth, many severe storms brew in the martian polar regions. Here, temperature contrasts between the cold carbon dioxide ("dry ice") seasonal frost cap and the warm ground adjacent to it--combined with a flow of cool polar air evaporating off the cap--sweeps up dust and funnels it into swirling dust storms along the cap edge. The dust storms shown here were observed during the recent northern spring by the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) in May 2002. The picture is a mosaic of daily global images from the MOC wide angle cameras. The north polar cap is the bright, frosty surface at the top.<p><br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA04050" onclick="window.open(this.href); return false;" title="Voir l'image PIA04050: Springtime North Polar Dust Storms sur le site de la NASA">Voir l'image PIA04050: Springtime North Polar Dust Storms sur le site de la NASA.</a></div>
PIA04050: Springtime North Polar Dust Storms
<h1>PIA04268: A Mid-Northern Summer/Southern Winter's Mars</h1><div class="PIA04268" lang="en" style="width:800px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>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.</p><p>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 top-left, top-center, bottom-right).</p><p>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 the bottom-center image), 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.</p><p>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.</p><br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA04268" onclick="window.open(this.href); return false;" title="Voir l'image PIA04268: A Mid-Northern Summer/Southern Winter's Mars sur le site de la NASA">Voir l'image PIA04268: A Mid-Northern Summer/Southern Winter's Mars sur le site de la NASA.</a></div>
PIA04268: A Mid-Northern Summer/Southern Winter's Mars
<h1>PIA04527: Dust Storm in Syria</h1><div class="PIA04527" lang="en" style="width:799px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;">MGS MOC Release No. MOC2-366, 20 May 2003<p>A dust storm rages in Syria Planum, south of the Labyrinthus Noctis troughs (at lower center) in this Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) composite of daily global images taken during the recent southern winter. In this view, water ice clouds are present over each of the five largest Tharsis volcanoes, Olympus Mons (right center), Alba Patera (upper center), Ascraeus Mons (near center), Pavonis Mons (toward lower left), and Arsia Mons (lower left). The summertime north polar residual water ice cap can be seen at the top of this picture. Sunlight illuminates the planet from the left.<p><br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA04527" onclick="window.open(this.href); return false;" title="Voir l'image PIA04527: Dust Storm in Syria sur le site de la NASA">Voir l'image PIA04527: Dust Storm in Syria sur le site de la NASA.</a></div>
PIA04527: Dust Storm in Syria
<h1>PIA04591: Mars 2003</h1><div class="PIA04591" lang="en" style="width:540px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;">MGS MOC Release No. MOC2-402, 25 June 2003<p>The Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) experiment consists of 3 different cameras: a narrow angle imager that provides the black-and-white high resolution views (up to 1.4 meters per pixel) of Mars, and 2 wide angle cameras, observing in red and blue wavelengths, from which color views of the entire planet are assembled each day. The wide angle cameras provide a daily record of changes in martian weather and surface frost as the seasons progress. MGS MOC has obtained a record of martian weather spanning a little over 2 martian years since it began systematic observations in March 1999.<p>The view of Mars shown here was assembled from MOC daily global images obtained on May 12, 2003. At that time, the northern hemisphere was in early autumn, and the southern hemisphere in early spring. At the left/center of this view are the four large Tharsis volcanoes: Olympus Mons, Ascraeus Mons, Pavonis Mons, and Arsia Mons. Stretching across the center of the globe is the ~5,000 kilometers (~3,000 miles) long Valles Marineris trough system. The seasonal south polar carbon dioxide frost cap is visible at the bottom of this view. A dust storm sweeps across the plains of northern Acidalia at the upper right. North is up, east is right, sunlight illuminates the planet from the left.<p><br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA04591" onclick="window.open(this.href); return false;" title="Voir l'image PIA04591: Mars 2003 sur le site de la NASA">Voir l'image PIA04591: Mars 2003 sur le site de la NASA.</a></div>
PIA04591: Mars 2003
<h1>PIA10694: Phoenix's Position on Mars</h1><div class="PIA10694" lang="en" style="width:640px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p><a href="/archive/PIA10694.mov"></a><br />Click on the image for the animation</p><p>This animation shows an orbital view sweeping upward from Olympus Mons, the tallest volcano in the solar system, to the location of NASA's Phoenix Mars Lander in the northern polar reaches of Mars. The animation then zooms in on the flat terrain where Phoenix touched down May 25, 2008.</p><p>Phoenix eased down to the surface of Mars at approximately 68 degrees north latitude, 234 degrees east longitude, landing in the center of the red circle at the end of the animation. Before Phoenix landed, engineers had predicted it would land within the blue ellipse.</p><p>Phoenix touched down on the Red Planet at 4:53 p.m. Pacific Time (7:53 p.m. Eastern Time), May 25, 2008, in an arctic region called Vastitas Borealis.</p><p>The shaded relief map is based on data from the Mars Orbiter Laser Altimeter on NASA's Mars Global Surveyor orbiter.</p><p>The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.<br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA10694" onclick="window.open(this.href); return false;" title="Voir l'image PIA10694: Phoenix's Position on Mars sur le site de la NASA">Voir l'image PIA10694: Phoenix's Position on Mars sur le site de la NASA.</a></div>
PIA10694: Phoenix's Position on Mars
<h1>PIA11029: Wind-Related Topography in Phoenix's Region of Mars (Animation)</h1><div class="PIA11029" lang="en" style="width:640px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p><a href="/archive/PIA11029.mov" class="external free" target="wpext"></a><br />Click on image for animation</p><p>This movie shifts from a global zoom indicating the Phoenix landing area on Mars to a topographical map indicating relative elevations in the landing region. The elevations could affect wind patterns at the site.</p><p>In particular, Phoenix is in a broad, shallow valley. The edge of the valley, about 150 meters (500 feet) above the floor, may provide enough of a slope to the east of Phoenix to explain winds coming from the east during nights at the site. Cooler, denser air could be sinking down the slope and toward the lander.</p><p>Atmospheric scientists on the Phoenix team are analyzing wind patterns to distiguish effects of nearby topography from larger-scale movement of the atmosphere in the polar region.</p><p>The elevation information for this topographical mapping comes from the Mars Orbiter Laser Altimeter on NASA's Mars Global Surveyor orbiter. The blue-coded area is the valley floor. Orange and yellow indicate relatively higher elevations.</p><p>The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver. JPL managed the Mars Global Surveyor mission for the NASA Science Mission Directorate.<br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA11029" onclick="window.open(this.href); return false;" title="Voir l'image PIA11029: Wind-Related Topography in Phoenix's Region of Mars (Animation) sur le site de la NASA">Voir l'image PIA11029: Wind-Related Topography in Phoenix's Region of Mars (Animation) sur le site de la NASA.</a></div>
PIA11029: Wind-Related Topography in Phoenix's Region of Mars (Animation)
<h1>PIA11202: Phoenix Landing Site Indicated on Global View</h1><div class="PIA11202" lang="en" style="width:800px;text-align:left;margin:auto;background-color:#000;padding:10px;max-height:150px;overflow:auto;"><p>NASA's Phoenix Mars Mission landed at 68.2 degrees north latitude, 234.2 degrees east longitude. The far-northern location of the site is indicated on this global view from the Mars Orbiter Camera on NASA's Mars Global Surveyor.</p><p>The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by JPL, Pasadena, Calif. Spacecraft development was by Lockheed Martin Space Systems, Denver.<br /><br /><a href="http://photojournal.jpl.nasa.gov/catalog/PIA11202" onclick="window.open(this.href); return false;" title="Voir l'image PIA11202: Phoenix Landing Site Indicated on Global View sur le site de la NASA">Voir l'image PIA11202: Phoenix Landing Site Indicated on Global View sur le site de la NASA.</a></div>
PIA11202: Phoenix Landing Site Indicated on Global View

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