Source- HiRISE IR and color JP2 images of north polar Mars dunes near the ice cap. The active streaking bright and dark fans, 3D surface alterations, and darkening polygon fracture venting, all are part of a chemistry and change of state, crystallinity display in the climate of Mars geological history, and current scenes. Araneiform 'Spider' formations in action. Frame about 1/8 mi H x 1/4 mi W. Latitude 80 degrees. ESP_016032_2600 - MRO/HiRISE catalog. credit:NASA/JPL/University of Arizona 2010

$Source- HiRISE IR and color JP2 images of north polar Mars dunes near the ice cap. The active streaking bright and dark fans, 3D surface alterations, and darkening polygon fracture venting, all are part of a chemistry and change of state, crystallinity display in the climate of Mars geological history, and current scenes. Araneiform 'Spider' formations in action. Frame about 1/8 mi H x 1/4 mi W. Latitude 80 degrees. ESP_016032_2600 - MRO/HiRISE catalog. credit:NASA/JPL/University of Arizona 2010$