 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
HiRISE Catches A Dust Devil On Mars
Tucson AZ (SPX) Jul 21, 2007 The University of Arizona-based High Resolution Imaging Experiment (HiRISE) group this week released a good look at a dust devil on Mars. This is not the storm bedeviling NASA's Mars Exploration Rovers, Spirit and Opportunity. The HiRISE camera captured the dust twister by chance in its photographic swath of a region in the southern hemisphere near Hellas Planitia during a Martian mid-afternoon early last month. The HiRISE camera is orbiting the Red Planet on NASA's Mars Reconnaissance Orbiter. The HiRISE image is of a region east of the Hellas impact basin and south of Reull Vallis. Dust devils form when the temperature of the atmosphere near the ground is much warmer than that above. The hot air rises, and under ideal conditions, forms a vortex that sucks in more warm air. If the vortex is strong enough, it will raise dust off the surface, forming a dust devil. Dust devils generally form in the afternoon because the sunlight needs sufficient time to warm the surface. Local time when this picture was taken was 3:08 p..m. The bright material is the dust within the vortex. A dark shadow cast by the dust devil is visible to the right. This dust devil is about 200 meters across (about 660 feet), but probably much smaller than that where it touches the surface. Scientists estimate from the length of its shadow that the dust devil is about 500 meters tall (about 1,600 feet). The HiRISE camera takes images of 3.5-mile-wide (6 km) swaths as the orbiter flies at about 7,800 mph between 155 and 196 miles (250 to 316 km) above Mars' surface. Professor Alfred McEwen of UA's Lunar and Planetary Laboratory is principal investigator for HiRISE. Related Links HiRise at LPL Mars Reconnaissance Orbiter HiRoc at Arizona CRISM at APL Mars News and Information at MarsDaily.com Lunar Dreams and more
Layers Exposed In Crater Near Mawrth Vallis
Tempe AZ (SPX) Jul 19, 2007This image covers an impact crater roughly 4 kilometers (2.5 miles) in diameter. The subimage shows just a small segment of the crater rim (1336 x 889; 3 MB). The surface outside the crater (top) is relatively dark, while the interior wall of the crater has a lighter tone. A few dark patches on the crater wall have small dunes or ripples on their surfaces, and are likely pits filled with dark sand. |
|
|
| The content herein, unless otherwise known to be public domain, are Copyright Space.TV Corporation. AFP and UPI Wire Stories are copyright Agence France-Presse and United Press International. ESA Portal Reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space.TV Corp on any Web page published or hosted by Space.TV Corp. Privacy Statement |
