Ice on Mars

The European Space Agency's (ESA) Mars Express spacecraft has sent back a spectacular image (Fig. 1) of water ice on the floor of an unnamed crater near Mars' north pole. The image was obtained with the Mars Express High Resolution Stereo Camera (HRSC). The crater is 35 kilometers (about 22 miles) wide and 2 kilometers (1.2 km) deep. According to the ESA web site, the resolution of the image is 15 meters (49 feet) per pixel.

Mars Express is the first European mission to another planet. The spacecraft was launched on 2 June 2003, and it entered orbit around Mars six months later. It carried the Beagle 2 lander, which was declared lost after signals were never received from it.

Images like the one in Fig. 1 require considerable processing. First, the raw data from the camera's blue, green, red and near-infrared filters are transmitted to Earth. The data for the various channels are then merged to provide the final image.

The post-processing of planetary images made by spacecraft provides a link to amateur scientists, for various commercial image processing programs can be applied to such imagery. Perhaps amateur scientists can apply clever processing methods to extract new information from images like those that were merged to form the one in Fig. 1.

You can learn much more about the Mars Express at the satellite's Frequently Asked Questions web site. This site links to much more about the Mars Express and its mission.

Forrest M. Mims III