Edited Mars Reconnaissance Orbiter image of the floor of a crater located near Voeykov Crater.

Edited Mars Reconnaissance Orbiter image of what looks like cracks on frost on the surface of Mars.

Edited Mars Reconnaissance Orbiter image of a candidate impact site for a small asteroid on Mars (where "candidate" means "virtually certain"). Color variant.

Edited Mars Reconnaissance Orbiter of pitted terrain in the Ultima Lingula region.

Edited Mars Reconnaissance Orbiter image of the central uplift of a crater near Pettit Crater. Color variant.

Edited Mars Reconnaissance Orbiter PR image of fractured mounds in Elysium Planitia.

Edited Mars Reconnaissance Orbiter image of part of Aram Chaos.

Edited Mars Reconnaissance Orbiter image of sand dunes on Mars. Color variant.

Edited Mars Reconnaissance Orbiter image of parts of Aram Chaos on Mars. Color/processing variant.

Edited Mars Reconnaissance Orbiter image of rugged Martian terrain.

Edited Mars Reconnaissance Orbiter image of pits and sand dunes in Hale Crater. Color/processing variant.

Gullies on Martian sand dunes, like these in Matara Crater, have been very active, with many flows in the last ten years. The flows typically occur when seasonal frost is present.

In this image from NASA's Mars Reconnaissance Orbiter we see frosts in and around two gullies, which have both been active before. There are no fresh flows so far this year, but HiRISE will keep watching.

The map is projected here at a scale of 50 centimeters (19.7 inches) per pixel. [The original image scale is 50.3 centimeters (19.8 inches) per pixel (with 2 x 2 binning); objects on the order of 151 centimeters (59.4 inches) across are resolved.] North is up.

Edited Mars Reconnaissance Orbiter image of a pit on a crater wall on Mars.

Edited Mars Reconnaissance Orbiter image of a lava dike on Mars.

Edited Mars Reconnaissance Orbiter image of frost on sand dunes.

Edited Mars Reconnaissance Orbiter image of an ancient lava flow in Alba Fossae on Mars. Color/processing variant.

Edited Mars Reconnaissance Orbiter</b image of east barchan sand dunes named Romo. Color variant.

Edited Mars Reconnaissance Orbiter image of a far north mesa with lots of dust devil tracks, first seen by Mariner 9.

Edited Mars Reconnaissance Orbiter image of sand dunes in Stokes Crater.

Edited Mars Reconnaissance Orbiter image of the west flank of Chasma Boreale with barchan and linear sand dunes. Color/processing variant.

Edited Mars Reconnaissance Orbiter image of sand dunes in Schaeberle Crater.

Edited Mars Reconnaissance Orbiter image of sand dunes near Meroe Patera. Color/processing variant.

Edited Mars Reconnaissance Orbiter image of sand dunes that looks suspiciously like circuit boards...

Edited Mars Reconnaissance Orbiter image of a 144 meter circular feature in the south polar region of Mars.

Edited Mars Reconnaissance Orbiter image of layered terrain on Mars. Color/processing variant.

Edited Mars Reconnaissance Orbiter image of a crater in the south polar region of Mars that appears to be smiling for the camera. Color/processing variant.

Image source: www.uahirise.org/hipod/ESP_067414_0945

Original caption: We’ve monitored the so-called Happy Face Crater in the south polar region of Mars for almost a decade. Two images that we took, one in 2011 and the other in 2020, at roughly the same season, show color variations that are due to different amounts of bright frost over darker red ground.

The “blobby” features in the polar cap are due to the sun sublimating away the carbon dioxide into these round patterns. You can see how nine years of this thermal erosion have made the “mouth” of the face larger. The “nose” consisted of a two circular depressions in 2011, and in 2020, those two depressions have grown larger and merged.

Measuring these changes throughout the Martian year help scientists understand the annual deposition and removal of polar frost, and monitoring these sites over long periods helps us understand longer term climate trends on the Red Planet.

ID: ESP_067414_0945

date: 13 December 2020

altitude: 247 km

NASA/JPL/UArizona

uahirise.org/hipod/ESP_067414_0945

Edited Mars Reconnaissance Orbiter image of a crater on Mars with a dune field in its middle situated such that it resembles a huge cat eye staring back at MRO.

Edited Mars Reconnaissance Orbiter image of chaotic terrain on the floor of Candor Chasma on Mars. Processing variant.

Edited Mars Reconnaissance Orbiter image of alluvial fan stratigraphy in Saheki Crater.

Edited Mars Reconnaissance Orbiter image of a mesa island in east Acidalia Planitia.

Edited Mars Reconnaissance Orbiter image of "dune convoys in West Olympia Undae. Color/processing variant.

Edited Mars Reconnaissance Orbiter image of part of Candor Chasma showing swirly rock and sand layers. Grayscale PR version.

Edited Mars Reconnaissance Orbiter image of material flows on the surface of Mars.

Edited Mars Reconnaissance Orbiter image of Libya Montes, a possible landing site for a future probe.

Original caption: Proposed Site for Future Exploration in Libya Montes

The Libya Montes are a highland terrain on Mars up-lifted by the giant impact that created the Isidis basin to the north.

NASA/JPL/University of Arizona (273 km above the surface, less than 5 km top to bottom and north is to the right.)

Source: www.uahirise.org/ESP_022970_1835

Edited Mars Reconnaissance Orbiter image of parts of Aram Chaos on Mars.

Edited Mars Reconnaissance Orbiter image of a crater in Melas Chasma being monitored.

Edited Mars Reconnaissance Orbiter image of a braided alluvial fan at the end of Karun Valles on Mars.

Edited Mars Reconnaissance Orbiter image of a stratigraphic boundary in Meridiani Planum. Color variant.

Edited Mars Reconnaissance Orbiter image of stratigraphy exposed by an impact crater.

Edited Mars Reconnaissance Orbiter image of sand dunes on Mars formed by cross winds.

Edited Mars Reconnaissance Orbiter image of a scarp in Utopia Planitia.

Edited Mars Reconnaissance Orbiter image of scalloped terrain in Utopia Planitia on Mars.

Edited Mars Reconnaissance Orbiter image of a heavily cratered mesa with crater ejecta. Color/processing variant.

Edited Mars Reconnaissance Orbiter image of a sand dune field over layers of bedrock on Mars.

Edited Mars Reconnaissance Orbiter image of mesas on a flat-looking Martian plain.

Edited Mars Reconnaissance Orbiter image of the central uplift of an impact crater.

Edited Mars Reconnaissance Orbiter image of fading dust devil tracks on Mars, being used to determine the rate of dustiness, which is, apparently, quite high.

Edited Mars Reconnaissance Orbiter image of the floor of Kaiser Crater.

Edited Mars Reconnaissance Orbiter image of a possible landing site for ESA's NASA's InSight mission.

This image shows a portion of a lobate debris apron along the bottom of a hill in the Promethei Terra region of Mars. This region contains many such mesas surrounded by lobate debris aprons that are thought to be ice-rich. These aprons have been interpreted as a variety of possible features including rock glaciers, ice-rich mass movements, or debris-covered glacial flows. Recent radar data have shown them to be composed of nearly 100% pure ice. Parallel grooves and ridges indicate the direction of flow.