This image of Coprates Catena was obtained in the early evening of January 1, 1998 by NASA's Mars Global Surveyor. The image covers a tiny fraction of the Valles Marineris canyons.

This image is a mosaic of the original data (at left) compared with the results of contrast enhancement (at right). The processing steps performed to create this image were:

  1. A long, narrow high-pass filter is applied in a vertical orientation to help reduce some of the instrument signature. This signature is seen as the streaking that is noticeable in the original data.
  2. A long, narrow low-pass filter is applied in a horizontal orientation to help create an intensity average for the image.
  3. The results of these filtering operations are the stretched to approximate a Gaussian distribution.
  4. The results of the high-pass and low-pass processing steps are averaged together to form the final product.
  5. The image is flipped about the vertical axis to correct for the camera orientation.
  6. The original and processed data are placed together in a mosaic.
  7. The completed image is sized down by a factor of 2, with interpolation, to make the finished result more manageable.

Other information available for this image is the following:

  • Orbit: 258
  • Range: 409.53 km
  • Resolution: 3.46 m/pixel
  • Image dimensions: 1024 X 9600 pixels, 3.5 km x 33.2 km
  • Line time: 0.50 msec
  • Emission angle: 29.90 degrees
  • Incidence angle: 69.59 degrees
  • Phase angle: 60.62 degrees
  • Scan rate: ~0.15 degree/sec
  • Start time: periapsis + 410 sec
  • Sequence submitted to JPL: Wed 04/22/98 21:45:00 PDT
  • Image acquired by MOC: Thu 04/23/98 12:23:02 PDT
  • Data retrieved from JPL: Fri 04/24/98 09:00 PDT
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