MGS MOC Release No. MOC2-301, 11 February 2002
Small view (315 KBytes)
Medium view (1 MByte)
Large view (3.6 MBytes)
The picture on the left (above, A) is a mosaic of three MOC high resolution images and one much lower-resolution Viking image. From left to right, the images used in the mosaic are: Viking 1 516A55, MOC E05-01904, MOC M21-00272, and MOC M08-03697. Image E05-01904 is the one taken in June 2001 by pointing the spacecraft. It captured the impact crater responsible for the rays. A close-up of the crater, which is only 130 meters (427 ft) across, is shown on the right (above, B). This crater is only one-tenth the size of the famous Meteor Crater in northern Arizona.
The June 2001 MOC image reveals many surprises about this feature. For one, the crater is not located at the center of the bright area from which the dark rays radiate. The rays point to the center of this bright area, not the crater. Further, the dark material ejected from the crater--immediately adjacent to the crater rim in the picture on the right (above, B)--is not continuously connected to the larger pattern of rays. Asymmetries in crater form and ejecta patterns are generally believed to occur when the impact is oblique to the surface. The offset of the crater from the center of the rays suggests that the meteor struck at an angle, most likely from the bottom/lower right (south/southeast). The strange geometry of the rays is quite different from that seen for rays associated with impact craters on the Moon and other airless bodies; one possible explanation is that they resulted from disruption of dust on the martian surface by winds generated by the shock wave as the meteor plunged through the martian atmosphere before it struck the ground.
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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