Firsoff Crater - False Color

Scaled Image

Image Credit: NASA/JPL/ASU

About this image

The THEMIS VIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. These false color images may reveal subtle variations of the surface not easily identified in a single band image. Today's false color image shows part of the floor of Firsoff Crater. Located in southern Arabia Terra, Firsoff Crater, and the neighboring Crommelin Crater, have large layered deposits on the crater floor. The circular feature at the bottom of the image is a smaller crater within Firsoff Crater. The layering of the interior deposit can be seen in the northern side of this smaller crater. Wind action has modified the large deposit. In this color combination dark blue typically indicates basaltic sand. Firsoff Crater is 90 km (56 miles) in diameter.

The THEMIS VIS camera is capable of capturing color images of the Martian surface using 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 using 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: 
V94812003 (View data in Mars Image Explorer)
2023-04-30 02:58
Thu, 2023-09-21
512 pixels (18 km)
1824 pixels (65 km)
0.035952 km/pixel
0.0361354 km/pixel


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