Edited Mars Reconnaissance Orbiter image of Gale Crater and the Curiosity Rover.

Edited Mars Reconnaissance Orbiter PR image of a crop of chaotic and uplifted bedrock on Mars.

Edited Mars Reconnaissance Orbiter image of the steep scarp on the edge of the north polar ice cap.

Image source: www.uahirise.org/ESP_054663_2650

Original caption: HiRISE has been re-imaging regions first photographed in 2006 through 2007, six Mars years ago. This long baseline allows us to see large, rare changes as well as many smaller changes.

One of the most actively changing areas on Mars are the steep edges of the North Polar layered deposits. This image shows many new ice blocks compared to an earlier image in December 2006. An animation shows one example, where a section of ice cliff collapsed. The older image (acquired in bin-2 mode) is not as sharp as the newer one.

Written by: Alfred McEwen (audio: Tre Gibbs) (25 June 2018)

Edited Mars Reconnaissance Orbiter image of Olivine in Syrtis Major. Processing variant.

Original caption:

CRISM Detection of Olivine in Syrtis Major

CRISM is a visible-infrared spectrometer instrument onboard the Mars Reconnaissance Orbiter. If that team detects something of interest, we will often take a high resolution image to view an area in greater detail. Olivine is a magnesium iron silicate.

NASA/JPL/University of Arizona (281 km above the surface, less than 5 km across.)

Source: www.uahirise.org/ESP_022733_2005

Edited Mars Reconnaissance Orbiter (At least I think it's from MRO) image of banded terrain on Mars. Color/processing variant.

Edited Mars Reconnaissance Orbiter image of sand dunes (continuing the Martian circuit board theme) rich in gypsum in a Martian north polar erg. Color variant.

Edited Mars Reconnaissance Orbiter image of cracked terrain on Mars.

Edited Mars Reconnaissance Orbiter image (cropped from the previous image) of a system of channels in the Hellas Basin.

Edited Mars Reconnaissance Orbiter image of an ancient river bed, now thoroughly dry.

Edited Mars Reconnaissance Orbiter image of a candidate landing spot (no mission indicated) in McLaughlin Crater. Color variant.

Edited Mars Reconnaissance Orbiter image of a crater in Terra Cimmeria with interesting gullies. (Lots of craters on Mars have gullies - there is no agreement, however, on how they were formed.)

Edited Mars Reconnaissance Orbiter PR image of a mound in Solis Planum on Mars. Processing variant.

An amazing aspect of Mars that is captured in many HiRISE images is geologic diversity within a small area. This image, of a crater in the Tyrrhena Terra region, was targeted to look at the geologic aspects of possible clays detected with the CRISM instrument. Fortuitously, a beautiful set of star dunes are visible on the western edge of a small crater within the larger target crater (this smaller crater is in the southwest [lower left] of the image). Star dunes form when sand is blown by winds coming from multiple directions, which is common in craters. This results in intersecting dunes, forming a polygonal, or "star" pattern. Here we show two zooms of the star dunes. The closest zoom (at right) shows lumpy deposits of sand in the interior of the star patterns, probably resulting from avalanches off of the dune slopes. The dune sands are most likely made of basalt, a common volcanic rock.

Edited Mars Reconnaissance Orbiter image of odd patterns in Eschus Chasma. Color variant.

Edited Mars Reconnaissance Orbiter image of a small channel on the floor of a large crater in Libya Montes.

Edited Mars Reconnaissance Orbiter image of large polygons (which remind me of dried lake beds) on Mars.

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 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 gullies on the side of Heaviside Crater.

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 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.