First MOC Public Requested Image: Caldera of Pavonis Mons View larger images NASA/JPL/Malin Space Science Systems

Mars Global Surveyor (MGS) reached the red planet six years ago, on 12 September 1997 (UTC). The Mars Orbiter Camera (MOC) began acquiring images a few days later, although systematic mapping from a nearly-circular, nearly-polar orbit did not begin until March 1999. Now in its extended mission, MOC continues to document and provide revelations about the geology and meteorology of Mars with more than 130,000 images received. The MGS MOC Public Target Request Site began taking public and science community suggestions for areas on Mars to be imaged by MOC on 20 August 2003. This pair of images is the first set to be obtained through the Public Target Request effort. The picture on the left is a MOC narrow angle (high resolution) view of a portion of the lower wall and floor of the Pavonis Mons caldera. The image on the right is a MOC red camera wide angle context image, taken at the same time as the high resolution view. The white box in the context frame shows the location of the high resolution picture.

The narrow angle MOC image has a resolution of 1.5 meters (~5 feet) per pixel and covers an area 1.5 kilometers (~0.9 mile) wide by 9 kilometers (5.6 miles) long. The context image covers much of the summit region of Pavonis Mons; it is about 115 km (~72 mi) wide. Sunlight illuminates both images from the lower left; north is toward the top/upper right; east to the right. The high resolution view is located near 0.4°N, 112.8°W.

Pavonis Mons is a broad shield volcano; its summit region is about 14 km (~8.7 mi) above the martian datum (above elevation 0); the caldera is about 4.6 km (~2.8 mi) deep. The caldera formed by collapse--a long time ago--as molten rock withdrew to greater depths within the volcano. The new high resolution picture shows that today the floor and walls of this caldera are covered by a thick (perhaps more than 1 meter/1 yard), textured mantle of dust. Larger boulders and rock outcroppings poke out from within this dust mantle; they are seen as small, dark dots and mounds on the lower slopes of the wall in the high resolution image. The picture partially overlaps some of a previous, lower-resolution view obtained in November 2001 (6 m/pixel; E10-01691 or subframe of E10-01691 in cases where a web browser cannot display an image with 16256 lines).

Each Public Target Request received at Malin Space Science Systems (MSSS) is examined by MSSS personnel, then placed in a database where it awaits a time in the future when the MGS spacecraft is predicted to fly over the suggested target. Any given request might wait in this database for weeks, months, or even a year or more; it is not possible to know more than a few days in advance whether a specific target is going to be imaged. The pair of images shown here were suggested in late August, 2003. A predicted ground track was seen to intersect the location of the requested picture on 1 September. The image was acquired on 4 September and received on Earth the following day. Data received through the MGS MOC Public Target Request effort are posted once a month at: http://www.msss.com/mars_images/moc/publicresults/. The next posting is expected in late October 2003, if additional public images are acquired before then.

All Images Credit: NASA/JPL/Malin Space Science Systems

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, California. 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, California and Denver, Colorado.