 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
Water Ice In Crater At Martian North Pole
Paris, France (ESA) Jul 29, 2005 These images, taken by the High Resolution Stereo Camera (HRSC) on board ESA�s Mars Express spacecraft, show a patch of water ice sitting on the floor of an unnamed crater near the Martian north pole. The HRSC obtained these images during orbit 1343 with a ground resolution of approximately 15 metres per pixel. The unnamed impact crater is located on Vastitas Borealis, a broad plain that covers much of Mars's far northern latitudes, at approximately 70.5� North and 103� East. The crater is 35 kilometres wide and has a maximum depth of approximately 2 kilometres beneath the crater rim. The circular patch of bright material located at the centre of the crater is residual water ice. This white patch is present all year round, as the temperature and pressure are not high enough to allow sublimation of water ice. It cannot be frozen carbon dioxide since carbon dioxide ice had already disappeared from the north polar cap at the time the image was taken (late summer in the Martian northern hemisphere). There is a height difference of 200 metres between the crater floor and the surface of this bright material, which cannot be attributed solely to water ice. It is probably mostly due to a large dune field lying beneath this ice layer. Indeed, some of these dunes are exposed at the easternmost edge of the ice. Faint traces of water ice are also visible along the rim of the crater and on the crater walls. The absence of ice along the north-west rim and walls may occur because this area receives more sunlight due to the Sun�s orientation, as highlighted in the perspective view.
3D anaglyph view of crater with water ice The colour images were processed using the HRSC nadir (vertical view) and three colour channels. The perspective views were calculated from the digital terrain model derived from the stereo channels. The 3D anaglyph images were created from the nadir channel and one of the stereo channels. Stereoscopic glasses are needed to view the 3D images Image resolution has been decreased for use on the internet. Community Email This Article Comment On This Article Related Links Mars Express SpaceDaily Search SpaceDaily Subscribe To SpaceDaily Express Mars News and Information at MarsDaily.com Lunar Dreams and more
Spirit Heading To 'Home Plate'
Pasadena CA (JPL) Jan 09, 2006Last week Spirit completed robotic-arm work on "El Dorado." The rover used all three of its spectrometers plus the microscopic imager for readings over the New Year's weekend. |
|
|
| The content herein, unless otherwise known to be public domain, are Copyright 1995-2006 - SpaceDaily.AFP and UPI Wire Stories are copyright Agence France-Presse and United Press International. ESA PortalReports are copyright European Space Agency. All NASA sourced material is public domain. Additionalcopyrights 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 SpaceDaily on any Web page published or hosted by SpaceDaily. Privacy Statement |
