PIA02020: South Melea Planum, By The Dawn's Early Light
 Target Name:  Mars
 Is a satellite of:  Sol (our sun)
 Mission:  Mars Global Surveyor (MGS)
 Spacecraft:  Mars Global Surveyor Orbiter
 Instrument:  Mars Orbiter Camera (MOC)
 Product Size:  233 x 449 pixels (w x h)
 Produced By:  Malin Space Science Systems
 Producer ID:  MOC2-126A P50357 MRPS94852
 Addition Date:  2000-06-14
 Primary Data Set:  MGS EDRs
 Full-Res TIFF:  PIA02020.tif (79.2 kB)
 Full-Res JPEG:  PIA02020.jpg (17.16 kB)

Click on the image above to download a moderately sized image in JPEG format (possibly reduced in size from original)

Original Caption Released with Image:

MOC "sees" by the dawn's early light! This picture was taken over the high southern polar latitudes during the first week of May 1999. The area shown is currently in southern winter darkness. Because sunlight is scattered over the horizon by aerosols--dust and ice particles--suspended in the atmosphere, sufficient light reaches regions within a few degrees of the terminator (the line dividing night and day) to be visible to the Mars Global Surveyor Mars Orbiter Camera (MOC) when the maximum exposure settings are used.

This picture shows a polygonally-patterned surface on southern Malea Planum. At the time the picture was taken, the sun was more than 4.5° below the northern horizon. The scene covers an area 3 kilometers (1.9 miles) wide, with the illumination from the top of the picture.

In this frame, the surface appears a relatively uniform gray. At the time the picture was acquired, the surface was covered with south polar wintertime frost. The highly reflective frost, in fact, may have contributed to the increased visibility of this surface.

This "twilight imaging" technique for viewing Mars can only work near the terminator; thus in early May only regions between about 67°S and 74°S were visible in twilight images in the southern hemisphere, and a similar narrow latitude range could be imaged in the northern hemisphere. MOC cannot "see" in the total darkness of full-borne night.

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.

Image Credit:
NASA/JPL/MSSS

Image Addition Date:
2000-06-14