Edited Mars Reconnaissance Orbiter image of clay-rich terrain in Oxia Planum and a candidate landing site for ESA's ExoMars.

Edited Mars Reconnaissance Orbiter PR image of sand dunes in the center of Juventae Chasma. Context image.

Original caption: The ultimate origin of the sediment that forms Martian dunes has long been debated. While sand dunes on Earth are primarily sourced by quartz-bearing components of granitic continental crust, it's often suggested that sand on Mars derives from eroded volcanic flows or sedimentary deposits, but exact sources are often vague.

This image reveals a unique situation where this small dune field occurs along the summit of the large 1-mile-tall mound near the center of Juventae Chasma. The layered mound slopes are far too steep for dunes to climb, and bedform sand is unlikely to come from purely airborne material. Instead, the mound's summit displays several dark-toned, mantled deposits that are adjacent to the dunes and appear to be eroding into fans of sandy material.

Along with local HiRISE images, spectral data from other instruments on MRO have confirmed such units are likely to be the sand source for these mound summit dunes and reveal how landscape evolution on Mars might occur.

The map is projected here at a scale of 25 centimeters (9.8 inches) per pixel. [The original image scale is 27.8 centimeters (10.9 inches) per pixel (with 1 x 1 binning); objects on the order of 83 centimeters (32.7 inches) across are resolved.] North is up.

The University of Arizona, Tucson, operates HiRISE, which was built by Ball Aerospace & Technologies Corp., Boulder, Colorado. NASA's Jet Propulsion Laboratory, a division of Caltech in Pasadena, California, manages the Mars Reconnaissance Orbiter Project for NASA's Science Mission Directorate, Washington.

Image Credit:

NASA/JPL-Caltech/Univ. of Arizona

Image Addition Date:

2018-10-01

Edited Mars Reconnaissance Orbiter image of a new impact crater on Mars with what looks like exposed ice next to the crater itself. Color/processing variant.

This observation shows layered bedrock that has been faulted and tilted. These layers were likely horizontal when the materials were first deposited, but are now tilted to high angles, approaching 90 degrees, so we get a good cross-sectional view from a bird's-eye view. The layers have distinctive colors, textures, and thicknesses, so it is easy to correlate layers from place to place. That makes it easy to measure the offset along the many faults breaking the layers. ASU-IPF-3087

Edited Mars Reconnaissance Orbiter image of the central peak of Alga Crater.

Edited Mars Reconnaissance Orbiter image of exposed layers in southern Argyre Planitia. Color variant.

This image shows a small rayed impact crater, about 160 meters (530 feet) in diameter, in the Tharsis region in the northern hemisphere of Mars. Relatively recent impacts form rays of ejecta that spray out radially from the crater. In addition to relatively fine material, large boulders and smaller secondary craters are visible in the rays surrounding this crater. Secondary craters are recognized by their shallow depths (in comparison to primary craters), irregular shapes, and appearance in clusters and linear chains.

Edited Mars Reconnaissance Orbiter image of sand dunes and dark streaks between craters.

This image of Utopia Planitia shows some deformed craters. The crater rims are not round but elliptical and even angular. The region is interesting because there are surface features (e.g., polygonal cracks) which suggest that water ice is close to the surface. A good example is just to the south of the featured image here. Other craters in the area appear old and eroded. Many are filled with material which could contain quantities of water ice. Were these deformed craters the result of an oblique impact or were they deformed afterwards by an as-yet unknown process?

Edited Mars Reconnaissance Orbiter image of chaotic terrain on the floor of Candor Chasma on Mars. Color/processing variant.

One of our JPL stars: Armin Kleinboehl. Armin studies the structure and dynamics of the Martian atmosphere.

Edited Mars Reconnaissance Orbiter image of a secondary crater (a crater created when ejecta from the primary crater impacts onto a surface, in this case, Mars) on Mars that resulted in a splash. Color/processing variant (which brings out the splash better).

Edited Mars Reconnaissance Orbiter image of bright sand dunes (looking very dark) in Syria Planum.

Image source: www.uahirise.org/hipod/ESP_032735_1680

Original caption: Bright Dunes in Syria Planum

This image shows curious bright deposits in Syria Planum, a high elevation region near the summit of the Tharsis rise.

Syria Planum has a history of surface changes documented in telescopic and low resolution orbital observations since the Viking era. The surface changes result from the relentless deposition and removal of bright dust, as the dust is transported by winds blowing from north to south across the rocky dark surface.

Isolated patches where thick dust deposits have accumulated can be identified in THEMIS night-time infrared observations. The dust deposits are cooler (darker) than the rocky surface both in daytime and at night. Our HiRISE image was centered on one of these cold spots to observe the interaction of the dust deposits with local topography.

Examining the image shows that the dust here has accumulated into linear arrays of broken ridges spaced about 50 meters apart, and extending from tens to hundreds of meters in length. Dust deposits are visible along the rim of the impact crater but much of the crater's ejecta deposits are strangely dust free.

At full resolution, the ridges appear to have a morphology that is clearly distinct from sand dunes and bright transverse aeolian ridges common elsewhere on Mars. Their steep faces are on the upwind side (in the present day wind regime), opposite to the sand dunes. The ridge crests are crenulated, suggesting that the deposits are currently being eroded by the wind. Fine layering is visible in the deposits, possibly indicating an alternation of dust and sand deposition.

Deposits such as these hint that while modern Mars is relatively benign, the surface of the planet was battered by much more ferocious winds in the recent past, perhaps during periods of high obliquity.

ID: ESP_032735_1680

date: 21 July 2013

altitude: 252 km

NASA/JPL/UArizona

uahirise.org/hipod/ESP_032735_1680

Edited Mars Reconnaissance Orbiter image of rust-colored sand dunes with dark shadows.

Edited Mars Reconnaissance Orbiter image of sample terrain in Noctis Fossae.

Edited Mars Reconnaissance Orbiter crop of an image of a dragon-fly shaped crater. I rotated this image 180 degrees.

Edited Mars Reconnaissance Orbiter image of sand dunes first seen by an earlier orbiter many years ago.

Edited Mars Reconnaissance Orbiter image of the central peak of Alga Crater. Color/processing variant.

Edited Mars Reconnaissance Orbiter image of the floor of Coprates Chasma on Mars.

Edited Mars Reconnaissance Orbiter image of cliffs of ancient ice on Mars. Color/processing variant.

Edited Mars Reconnaissance Orbiter image of part of Coprates Chasma

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

Edited Mars Reconnaissance Orbiter image of channels near Jezero Crater. Perseverance is not visible in this image.

Edited Mars Reconnaissance Orbiter image of a sharply-angled fracture on the flank of the volcano Pavonis Mons on Mars. Color/processing variant.

This is an IRB (Infrared, Red, Blue) image, meaning some infrared features not visible in human-seeable colors are visible.

This is of a feature I requested to be imaged via the HiWish web site. This site lets anyone suggest a location on Mars to be imaged as long as you can come up with a plausible justification (eg, "interesting-looking right-angle bend in a fracture" or "Marvin the Martian's Summer Home in Utopia Planitia" (although the last one may be ignored)). I've had three or four of my suggestions accepted and it's always a thrill to see them published.

www.uahirise.org/hiwish/

JPL's title for this image is "Fractures and Pits on Flank of Pavonis Mons."

Image source: www.uahirise.org/ESP_056616_1800

Edited Mars Reconnaissance Orbiter image of light sand dunes and dark sand dunes in Nili Fossae. Color/processing variant.

Edited Mars Reconnaissance Orbiter image of a source of gypsum on sand (gypsum) dunes on Mars. Color variant.

Edited Mars Reconnaissance Orbiter image of the monitoring of the slopes of a crater.

Edited Mars Reconnaissance Orbiter image of avalanches from a cliff on a the north polar ice cap on Mars. (Larger version of what I posted earlier.)

Edited Mars Reconnaissance Orbiter image of the central peak of Alga Crater. Color/processing variant.

Edited Mars Reconnaissance Orbiter image of a source of gypsum on sand (gypsum) dunes on Mars.

This targeted image from the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) shows a region of heavily altered rock in Mars' ancient cratered highlands. The featured region is just south of Mawrth Vallis, a channel cut by floodwaters deep into the highlands.

CRISM acquired the image at 1216 UTC (8:16 a.m. EDT) on Oct. 2, 2006, near 25.4 degrees north latitude, 340.7 degrees east longitude. It covers an area about 13 kilometers (8 miles) long and, at the narrowest point, about 9 kilometers (5.6 miles) wide. At the center of the image, the spatial resolution is as good as 35 meters (115 feet) per pixel. The image was taken in 544 colors covering 0.36-3.92 micrometers.

This image includes four renderings of the data, all map-projected. At top left is an approximately true-color representation. At top right is false color showing brightness of the surface at selected infrared wavelengths. In the two bottom views, brightness of the surface at different infrared wavelengths has been compared to laboratory measurements of minerals, and regions that match different minerals have been colored. The bottom left image shows areas high in iron-rich clay, and the bottom right image shows areas high in aluminum-rich clay.

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

Edited Mars Reconnaissance Orbiter image of colorful layers of bedrock in Terra Sirenum.

Edited Mars Reconnaissance Orbiter image of part of a very straight and large crack on Mars - part of Cerberus Fossae. Processing variant.

Edited Mars Reconnaissance Orbiter image of layers and ridges in a crater on Mars. Color/processing variant.

Edited Mars Reconnaissance Orbiter image of diverse clays near Mawrth Vallis. Color variant.

Although large gullies (ravines) are concentrated at higher latitudes, there are gullies on steep slopes in equatorial regions, as seen in this image captured by NASA's Mars Reconnaissance Orbiter (MRO). An enhanced-color close-up shows part of the rim and inner slope of Krupac Crater located just 7.8 degrees south of the equator.

The colors of the gully deposits match the colors of the eroded source materials. Krupac is a relatively young impact crater, but exposes ancient bedrock. Krupac Crater also hosts some of the most impressive recurring slope lineae (RSL) on equatorial Mars outside of Valles Marineris.

Another close look shows some RSL flowing downhill (to the left). The RSL leave bright deposits when inactive from previous years; this year's active RSL are the thin dark lines.

The map is projected here at a scale of 25 centimeters (9.8 inches) per pixel. [The original image scale is 26.3 centimeters (10.4 inches) per pixel (with 1 x 1 binning); objects on the order of 79 centimeters (31.1 inches) across are resolved.] North is up.

Edited Mars Reconnaissance Orbiter context image of a Martian north polar scarp where an avalanche of carbon dioxide frost was caught in the act. The grayscale image was created by NASA and is the red channel. Lots of really interesting detail to see!

Original caption: This scarp at the edge of the North Polar layered deposits of Mars is the site of the most frequent frost avalanches seen by HiRISE. At this season, northern spring, frost avalanches are common and HiRISE monitors the scarp to learn more about the timing and frequency of the avalanches, and their relationship to the evolution of frost on the flat ground above and below the scarp.

This picture managed to capture a small avalanche in progress, right in the color strip. See if you can spot it in the browse image, and then click on the cutout to see it at full resolution. The small white cloud in front of the brick red cliff is likely carbon dioxide frost dislodged from the layers above, caught in the act of cascading down the cliff. It is larger than it looks, more than 20 meters across, and (based on previous examples) it will likely kick up clouds of dust when it hits the ground.

The avalanches tend to take place at a season when the North Polar region is warming, suggesting that the avalanches may be triggered by thermal expansion. The avalanches remind us, along with active sand dunes, dust devils, slope streaks and recurring slope lineae, that Mars is an active and dynamic planet.

Written by: Paul Geissler (30 September 2015)

Image and caption source: hirise.lpl.arizona.edu/ESP_042572_2640

Edited Mars Reconnaissance Orbiter image of sand dunes on the southern highlands.

Edited Mars Reconnaissance Orbiter image of Curiosity in Gale Crater. This is an enlarged part of a much larger image (see following images) that shows Curiosity and some of her tracks in the sand. Color/processing variant.

Edited Mars Reconnaissance Orbiter image of inverted channels with lots of colors in Kasimov Crater on Mars.

Edited NASA PR image from Mars Reconnaissance Orbiter showing the Curiosity Rover near the base of Mount Sharp in Gale Crater.

Image source: photojournal.jpl.nasa.gov/catalog/PIA23341

Original caption: NASA's Curiosity Mars rover can be seen in this image taken from space on May 31, 2019, by the High Resolution Imaging Science Experiment (HiRISE) camera aboard the Mars Reconnaissance Orbiter (MRO). In the image, Curiosity appears as a bluish speck.

The image shows Curiosity at a location called "Woodland Bay." It's just one of many stops the rover has made in an area referred to as the "clay-bearing unit" on the side of Mount Sharp, a 3-mile-tall (5-kilometer-tall) mountain inside of Gale Crater.

Look carefully at the inset image, and you can make out what it is likely Curiosity's "head," technically known as the remote sensing mast. A bright spot appears in the upper-left corner of the rover. At the time this image was acquired, the rover was facing 65 degrees counterclockwise from north, which would put the mast in about the right location to produce this bright spot.

The University of Arizona, Tucson, operates HiRISE, which was built by Ball Aerospace & Technologies Corp., Boulder, Colorado. NASA's Jet Propulsion Laboratory, a division of Caltech in Pasadena, California, manages the Mars Reconnaissance Orbiter Project for NASA's Science Mission Directorate, Washington.

Image Credit:

NASA/JPL-Caltech

Image Addition Date:

2019-07-12

Edited Mars Reconnaissance Orbiter image of a sharply-angled fracture on the flank of the volcano Pavonis Mons on Mars.

This is an IRB (Infrared, Red, Blue) image, meaning some infrared features not visible in human-seeable colors are visible.

This is of a feature I requested to be imaged via the HiWish web site. This site lets anyone suggest a location on Mars to be imaged as long as you can come up with a plausible justification (eg, "interesting-looking right-angle bend in a fracture" or "Marvin the Martian's Summer Home in Utopia Planitia" (although the last one may be ignored)). I've had three or four of my suggestions accepted and it's always a thrill to see them published.

www.uahirise.org/hiwish/

JPL's title for this image is "Fractures and Pits on Flank of Pavonis Mons."

Image source: www.uahirise.org/ESP_056616_1800

Edited Mars Reconnaissance Orbiter image of Curiosity in Gale Crater. This is the much larger image of Gale Crater with Curiosity (this is the RGB version).

Edited Mars Reconnaissance Orbiter image of the internal structure of the residual south polar ice cap. Processing variant.

Edited Mars Reconnaissance Orbiter PR image of a layer of rocky material cut by some process (perhaps flowing water a billion or two years ago) and now filled by sand dunes. Color/processing variant.

This image from NASA's Mars Reconnaissance Orbiter shows the north-facing wall of a moat-like depression in the middle of Terby Crater, exposing a beautiful 400 meter-high sequence of light-toned, repetitive sedimentary layers. These deposits are often obscured by darker-toned patches of material as well as ripples and dunes.

The deposits in Terby, located on the northern rim of Hellas Planitia, are consistent with deposition in a standing body of water. The layers have been proposed as science targets for future landed missions.

Edited Mars Reconnaissance Orbiter context image of an ice-filled crater on the northern plains of Mars.

Edited Mars Reconnaissance Orbiter image of a central uplift and sand dunes in a crater in the Hesperia region of Mars.

Edited Mars Reconnaissance Orbiter image of frost on gullies in a crater on the northern plains of Mars.