Ganges Chasma

Scaled Image

Image Credit: NASA/JPL/ASU

About this image

This image was collected December 8, 2002 during southern winter season. The local time at the image location was about 4:45 pm. The image shows an area of the floor of Ganges Chasma and shows dark dunes and brighter wind sculpted hills of unknown origin.
The THEMIS VIS camera is capable of capturing color images of the martian surface using its five different color filters. In this mode of operation, the spatial resolution and coverage of the image must be reduced to accommodate the additional data volume produced from the use of multiple filters. To make a color image, three of the five filter images (each in grayscale) are selected. Each is contrast enhanced and then converted to a red, green, or blue intensity image. These three images are then combined to produce a full color, single image. Because the THEMIS color filters don't span the full range of colors seen by the human eye, a color THEMIS image does not represent true color. Also, because each single-filter image is contrast enhanced before inclusion in the three-color image, the apparent color variation of the scene is exaggerated. Nevertheless, the color variation that does appear is representative of some change in color, however subtle, in the actual scene. Note that the long edges of THEMIS color images typically contain color artifacts that do not represent surface variation.

Please see the THEMIS Data Citation Note for details on crediting THEMIS images. 


Image ID: 
V04359003 (View data in Mars Image Explorer)
2002-12-08 01:54
Thu, 2004-06-03
512 pixels (18 km)
1440 pixels (50 km)
0.034833 km/pixel
0.035279 km/pixel


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