Close-Up Pictures of Mars

"The linearity of the volcanic vent shown in this HiRISE image, in conjunction with evidence of lava flow from the vent, suggests control by combined volcano-tectonic processes."

"Sand dunes like these seen in this image have been observed to creep slowly across the surface of Mars through the action of the wind. These are a particular type of dune called a 'barchan,' which forms when the wind blows in one direction (here, east to west) for long periods of time. Barchan dunes are common on Mars and in the desert regions of the Earth."

"This image covers part of the floor of a large ancient impact crater, near the western rim. The subimage shows layered deposits, many with distinct colors (the colors are enhanced or exaggerated). These layers have a morphology similar to that seen elsewhere on Mars in obvious alluvial fans where channels emerge into craters."

"What we see are thin condensate clouds moving relative to surface features. They appear to move 200 meters distance over the 0.1855 second between the infrared and blue-green imaging, or 1.08 kilometers per second!"

"This site along a Coprates Chasma ridge shows what are called recurring slope lineae (or RSL) on generally north-facing slopes in northern Summer/southern Winter."

"Oxus Patera is an ancient, eroded depression in northern Arabia Terra. It is not known how Oxus Patera formed, though it has been suggested that the feature represents an ancient caldera formed through collapse and explosive volcanism."

"This image shows numerous dark shapes and bright spots on a sand dune in the Northern polar regions of Mars.

The bright spots are carbon dioxide frost. On Mars, the main atmospheric component is carbon dioxide, which circulates seasonally between the atmosphere and the polar regions. One of the reasons that permit this process is the fact that temperatures on Mars are much colder than on Earth, which allows carbon dioxide frost to condense on the surface in winter."