Knob in the South Polar Layered Deposits of Mars

These craters on Tharsis are first visible as new dark spots observed by NASA Mars Reconnaissance Orbiter Context Camera CTX, which can view much larger areas, and then imaged by HiRISE for a close-up look.

These craters on Tharsis are first visible as new dark spots observed by NASA Mars Reconnaissance Orbiter Context Camera CTX, which can view much larger areas, and then imaged by HiRISE for a close-up look.

MarsMars Reconnaissance Orbiter MRO