|
|
Mid-Winter Dust Storms Near
…
PIA03222
Sol (our sun)
Mars Orbiter Camera
| Title |
Mid-Winter Dust Storms Near Hellas Planitia |
| Original Caption Released with Image |
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. |
|
Tongue-Shaped Flow Feature i
…
PIA09594
Sol (our sun)
HiRISE
| Title |
Tongue-Shaped Flow Feature in Hellas Planitia |
| Original Caption Released with Image |
Click on image for larger version This HiRISE image (PSP_002320_1415 [ http://hirise.lpl.arizona.edu/PSP_002320_1415 ]) captures a tongue-shaped lobate flow feature along a interior crater wall located in eastern Hellas Planitia. The flow feature is approximately 5 kilometers long and 1 kilometer wide with a partial double inner ridge and raised outer margin. The flow feature's surface is generally devoid of impact craters and parts of its outer margin have deflected around obstacles. Similar flow features, though not as distinctively tongue-shaped as this one, are found in many other craters throughout the southern mid-latitudes of Mars. Recent studies of these flow features have determined a latitudinal dependence to which side of the crater interior these features are formed upon. For this particular flow feature, it has formed on the pole-facing slope. This polar or equatorial-facing preference has implications for the amount of solar isolation these slopes are receiving, which may be a result of recent climate change due to shifts from low to high obliquity. Although these Martian flow features may have Earth analogs such as rock glaciers, uncertainty remains as to what types of fluvial, glacial and mass-wasting processes are involved in their formation. This particular flow feature was imaged previously by the Mars Orbiter Camera (MOC) onboard NASA's Mars Global Surveyor spacecraft. Observation Geometry Acquisition date:1 January 2007 Local Mars time: 3:46 PM Degrees latitude (centered): -38.1 ° Degrees longitude (East): 113.2 ° Range to target site: 255.2 km (159.5 miles) Original image scale range: 25.5 cm/pixel (with 1 x 1 binning) so objects ~77 cm across are resolved Map-projected scale: 25 cm/pixel and north is up Map-projection: EQUIRECTANGULAR Emission angle: 9.4 ° Phase angle: 75.0 ° Solar incidence angle: 67 °, with the Sun about 23 ° above the horizon Solar longitude: 171.9 °, Northern Summer NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Mars Reconnaissance Orbiter for NASA's Science Mission Directorate, Washington. Lockheed Martin Space Systems, Denver, is the prime contractor for the project and built the spacecraft. The High Resolution Imaging Science Experiment is operated by the University of Arizona, Tucson, and the instrument was built by Ball Aerospace and Technology Corp., Boulder, Colo. |
|
Tongue-Shaped Flow Feature i
…
PIA09594
Sol (our sun)
HiRISE
| Title |
Tongue-Shaped Flow Feature in Hellas Planitia |
| Original Caption Released with Image |
Click on image for larger version This HiRISE image (PSP_002320_1415 [ http://hirise.lpl.arizona.edu/PSP_002320_1415 ]) captures a tongue-shaped lobate flow feature along a interior crater wall located in eastern Hellas Planitia. The flow feature is approximately 5 kilometers long and 1 kilometer wide with a partial double inner ridge and raised outer margin. The flow feature's surface is generally devoid of impact craters and parts of its outer margin have deflected around obstacles. Similar flow features, though not as distinctively tongue-shaped as this one, are found in many other craters throughout the southern mid-latitudes of Mars. Recent studies of these flow features have determined a latitudinal dependence to which side of the crater interior these features are formed upon. For this particular flow feature, it has formed on the pole-facing slope. This polar or equatorial-facing preference has implications for the amount of solar isolation these slopes are receiving, which may be a result of recent climate change due to shifts from low to high obliquity. Although these Martian flow features may have Earth analogs such as rock glaciers, uncertainty remains as to what types of fluvial, glacial and mass-wasting processes are involved in their formation. This particular flow feature was imaged previously by the Mars Orbiter Camera (MOC) onboard NASA's Mars Global Surveyor spacecraft. Observation Geometry Acquisition date:1 January 2007 Local Mars time: 3:46 PM Degrees latitude (centered): -38.1 ° Degrees longitude (East): 113.2 ° Range to target site: 255.2 km (159.5 miles) Original image scale range: 25.5 cm/pixel (with 1 x 1 binning) so objects ~77 cm across are resolved Map-projected scale: 25 cm/pixel and north is up Map-projection: EQUIRECTANGULAR Emission angle: 9.4 ° Phase angle: 75.0 ° Solar incidence angle: 67 °, with the Sun about 23 ° above the horizon Solar longitude: 171.9 °, Northern Summer NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Mars Reconnaissance Orbiter for NASA's Science Mission Directorate, Washington. Lockheed Martin Space Systems, Denver, is the prime contractor for the project and built the spacecraft. The High Resolution Imaging Science Experiment is operated by the University of Arizona, Tucson, and the instrument was built by Ball Aerospace and Technology Corp., Boulder, Colo. |
|
|
