A single depression from a larger sinuous chain of pits located at 34.6°N, 43.5°W in NAC frame M102443238R. Image is 1.5 kilometers wide and light is incident from the left at an angle of 78°.
This unnamed sinuous chain of pits was suggested to be a collapsed lava tube (see Wilhelms' Geologic History of the Moon). New high resolution NAC images (e.g., M102443238R) provide a new look at the area. This particular feature transitions from a discontinuous sinuous rille into a wrinkle ridge. Some scientists have suggested that wrinkle ridge faults interact with lava tubes, with the wrinkle ridge exploiting a zone of mechanical weakness (the lava tube) in the preexisting basalt deposit. In this NAC image, the topographic depressions are non-circular, with collapse rims. Many of the pits have boulders on the interior walls. If these depressions were created by impacts, each pit would have a raised rim and an ejecta blanket.
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|This section of WAC frame M117773324 shows the area where the feature transitions from a chain of collapse pits to a continuous uncollapsed segment. A large depression at the northern tip of the chain maybe a possible source region for the flow of lava across this region. The chain is approximately 50 kilometers long. Image resolution 58.9 meters/pixel|
NASA's Goddard Space Flight Center built and manages the mission for the Exploration Systems Mission Directorate at NASA Headquarters in Washington. The Lunar Reconnaissance Orbiter Camera was designed to acquire data for landing site certification and to conduct polar illumination studies and global mapping. Operated by Arizona State University, LROC consists of a pair of narrow-angle cameras (NAC) and a single wide-angle camera (WAC). The mission is expected to return over 70 terabytes of image data.