Investigating Mars: Ascraeus Mons

This image shows a collapse feature on the southeastern flank of the volcano. The circular/scalloped margin of the collapse is typical for ceiling collapse into a lava tube. However, the potential lava tube is perpendicular to the surface flows. The linear nature and relationship to the surface flows likely indicate that a preexisting tectonic graben occurred here and hosted lava flows that may have become lava tube flows. So in this case, the collapse feature formed by a combination of tectonic and volcanic processes.

The Odyssey spacecraft has spent over 15 years in orbit around Mars, circling the planet more than 69000 times. It holds the record for longest working spacecraft at Mars. THEMIS, the IR/VIS camera system, has collected data for the entire mission and provides images covering all seasons and lighting conditions. Over the years many features of interest have received repeated imaging, building up a suite of images covering the entire feature. From the deepest chasma to the tallest volcano, individual dunes inside craters and dune fields that encircle the north pole, channels carved by water and lava, and a variety of other feature, THEMIS has imaged them all. For the next several months the image of the day will focus on the Tharsis volcanoes, the various chasmata of Valles Marineris, and the major dunes fields. We hope you enjoy these images!