A portion of Chasma Boreale, a large canyon incised into Mars’ north polar ice cap. Computer models suggest this canyon was carved by extremely cold air flowing at high speeds off the ice cap, which over millenia have cut deep into the ice. In this location Chasma Boreale is about 1.5 km (4600 ft) deep.
Erosion has exposed internal layers of the ice cap, which are thought to record hundreds of thousands or millions of years of climate variation. These layers contain varying levels of dust, corresponding to different stages of the Martian climate cycle. Several sequences of layers, which are deposited on previous sequences at an angle, likely record previous canyons eroded into the ice cap, or major meltbacks of the cap.
This image was created using the CRISM imaging spectrometer. Each pixel of a CRISM image contains a 500 point spectrum, from which a color can be reconstructed. This reconstructed color was overlaid on a higher-resolution image taken with the Mars Reconnaissance Orbiter Context Camera (CTX), which simultaneously took a photo while CRISM was collecting data.
This image was taken on November 12, 2006. It uses CRISM observation FRT00002FA6 and CTX observation P01_001386_2649_XI_84N357W.
Image Credit: NASA / JPL / JHUAPL / MSSS / Justin Cowart
Tagged: , Mars Reconnaissance Orbiter , Mars , CRISM , CTX , Chasma Borealis , ice cap , layers