Edited Mars Reconnaissance Orbiter PR image of a crop of chaotic and uplifted bedrock on Mars. Color/processing variant.

Edited Mars Reconnaissance Orbiter image of terrain south of Mangala Fossa. Color/processing variant.

Edited Mars Reconnaissance Orbiter image of sand dunes on the floor of Renaudot Crater. Color/processing variant.

Edited Mars Reconnaissance Orbiter image of a dust devil seen from the top soon after it formed on Mars.

Edited Mars Reconnaissance Orbiter image of channels and sand dunes in Aram Chaos on Mars. Color/processing variant.

Heavily processed image of Assam. I used a Mars Reconnaissance Orbiter image of Danielson Crater as the seed image.

Edited Mars Reconnaissance Orbiter image of an eroding edge of a crater in Maadim Valls. Color/processing variant.

Edited Mars Reconnaissance Orbiter image of gullies exposing layers of different-colored bedrock on Mars.

Edited Mars Reconnaissance Orbiter image of a crater in polar terrain.

Edited Mars Reconnaissance Orbiter image of rocky ground and sand dunes.

Edited Mars Reconnaissance Orbiter image of terrain west of Mclaughlin Crater.

Edited Mars Reconnaissance Orbiter</b image of atypical landforms in polar erg sand dunes. Color variant.

Edited Mars Reconnaissance Orbiter image of layered bedrock in the Meridiani Region. Processing variant.

Edited Mars Reconnaissance Orbiter image of a steep scarp on the edge of the north polar layer on Mars. Color/processing variant.

Edited Mars Reconnaissance Orbiter image of rocky outcroppings in Mawrth Vallis on Mars. Color/processing variant.

Edited Mars Reconnaissance Orbiter image of sand dunes buried by water ice. Color variant.

Edited Mars Reconnaissance Orbiter image of dunes in Jeans Crater.

Edited Mars Reconnaissance Orbiter image of a candidate landing site for NASA's Mars 2020 rover mission, in Gusev Crater (the same crater where Spirit Landed in 2004).

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

Edited Mars Reconnaissance Orbiter image of a circular feature (not necessarily a crater) in the residual ice cap of the South Pole of Mars.

Edited Mars Reconnaissance Orbiter image of dust devil tracks in Brazos Basin.

Edited Mars Reconnaissance Orbiter image of the colors at the top of Coprates Chasma on Mars. Color/processing variant.

Edited Mars Reconnaissance Orbiter image of part of Mawrth Vallis on Mars.

Edited MRO image of defrosting patterns on ridges in an area of Mars known (colloquially) as "Inca City."

Edited Mars Reconnaissance Orbiter image of a dune field in east Endeavour Crater, which is where Opportunity is currently operating. Color variant.

Edited Mars Reconnaissance Orbiter image of West Ladon Valles on Mars. Color/processing variant.

Edited Mars Reconnaissance Orbiter image of part of Aram Chaos.

Edited Mars Reconnaissance Orbiter image of ejecta from sublimating carbon dioxide in the Martian south polar area.

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 sand dunes in Nili Patera on Mars.

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 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.

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 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 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.