View allAll Photos Tagged MarsReconnaissanceOrbiter
Edited Mars Reconnaissance Orbiter image of mounds in Chryse Planitia.
Image source: photojournal.jpl.nasa.gov/catalog/PIA22682
Original caption: This image was acquired on May 15, 2018 by NASA's Mars Reconnaissance Orbiter. This observation shows relatively bright mounds scattered throughout darker and diverse surfaces in Chryse Planitia. These mounds are hundreds of meters in size. The largest of the mounds shows a central pit, similar to the collapsed craters found at the summit of some volcanoes on Earth. The origins of these pitted mounds or cratered cones are uncertain. They could be the result of the interaction of lava and water, or perhaps formed from the eruption of hot mud originating from beneath the surface.
These features are very interesting to scientists who study Mars, especially to those involved in the ExoMars Trace Gas Orbiter mission. If these mounds are indeed mud-related, they may be one of the long sought after sources for transient methane on Mars.
The map is projected here at a scale of 50 centimeters (19.7 inches) per pixel. [The original image scale is 60.5 centimeters (23.8 inches) per pixel (with 2 x 2 binning); objects on the order of 181 centimeters (71.3 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:
2018-09-04
Edited Mars Reconnaissance Orbiter/Mars Express/Mars Global Surveyor PR image and data showing the relative elevations in Jezero Crater, and ancient and very much dried up lake bed that was originally a crater on Mars. The circle shows the intended landing ellipse for Perseverance in February of 2021. Color/processing variant.
Image source: photojournal.jpl.nasa.gov/catalog/PIA23511
Original caption: Lighter colors represent higher elevation in this image of Jezero Crater on Mars, the landing site for NASA's Mars 2020 mission. The oval indicates the landing ellipse, where the rover will be touching down on Mars. The color added to this image helps the crater rim stand out clearly, and makes it easier to spot the shoreline of a lake that dried up billions of years ago.
Scientists want to visit this shoreline because it may have preserved fossilized microbial life, if any ever formed on Mars.
The image was created using data from a combination of instruments and spacecraft: NASA's Mars Global Surveyor and its Mars Orbiter Laser Altimeter (MOLA); NASA's Mars Reconnaissance Orbiter and its Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) and Context Camera (CTX); and the European Space Agency's Mars Express and its High Resolution Stereo Camera (HRSC).
The Johns Hopkins University Applied Physics Laboratory in Laurel, Maryland, led the work to build the CRISM instrument and operates CRISM in coordination with an international team of researchers from universities, government and the private sector. Malin Space Science Systems in San Diego built and operates CTX. MOLA was built and operated by a team headed at NASA Goddard Space Flight Center in Greenbelt, Maryland.
Image Credit:
NASA/JPL-Caltech/MSSS/JHU-APL/ESA
Image Addition Date:
2019-11-12
Edited Mars Reconnaissance Orbiter image of blue sand dunes in Melas Chasma. The color is blue because the image is infrared (which, if you look at that statement from a purely vocabulary-level, makes no sense whatsoever). Color/processing variant.
Image source: photojournal.jpl.nasa.gov/catalog/PIA22783
Original caption: This color-infrared image shows sand dunes in Melas Chasma, located within the Valles Marineris canyon system. The dark-blue and purple colors indicate coarse-grained sands that are comprised of basalt, an iron and magnesium-rich volcanic rock that formed from cooled lava millions of years ago when volcanism was an active process on Mars.
Migrating sand dunes often lead to the erosion and excavation of underlying material; regions where there are active dune fields are ideal places to search for exposed bedrock. Repeated imaging of dunes may also show changes that provide evidence for active surface processes related to wind patterns and climate.
The map is projected here at a scale of 25 centimeters (9.8 inches) per pixel. [The original image scale is 26.5 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.
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 PR image of layers stacked up on the floor of an impact crater on Mars. Processing variant.
Image source: photojournal.jpl.nasa.gov/catalog/PIA09578
Original caption: This HiRISE image shows a stack of layers on the floor of an impact crater roughly 30 km across. Many of the layers appear to be extremely thin, and barely resolved.
In broad view, it is clear that the deposit is eroding into a series of ridges, likely due to the wind. Below the ridges, additional dark-toned layered deposits crop out. These exhibit a variety of textures, some of which may be due to transport of material.
The light ridges are often capped by thin dark layers, and similar layers are exposed on the flanks of the ridges. These layers are likely harder than the rest of the material, and so armor the surface against erosion. They are shedding boulders which roll down the slope, as shown in the subimage (figure 1). Although these cap layers are relatively resistant, the boulders do not seem to accumulate at the base of the slope, so it is likely that they also disintegrate relatively quickly.
The subimage shown is 250 meters wide. The light is from the left. Boulders can be seen on the slopes of the ridges along with thin dark layers including the cap layer, but they are absent on the spurs where the resistant cover has been eroded. This demonstrates that the boulders come only from the dark layers, and are not embedded in the rest of the deposit.
Observation Geometry
Image PSP_001503_1645 was taken by the High Resolution Imaging Science Experiment (HiRISE) camera onboard the Mars Reconnaissance Orbiter spacecraft on 21-Nov-2006. The complete image is centered at -15.3 degrees latitude, 89.7 degrees East longitude. The range to the target site was 256.3 km (160.2 miles). At this distance the image scale is 25.6 cm/pixel (with 1 x 1 binning) so objects ~77 cm across are resolved. The image shown here has been map-projected to 25 cm/pixel and north is up. The image was taken at a local Mars time of 03:35 PM and the scene is illuminated from the west with a solar incidence angle of 62 degrees, thus the sun was about 28 degrees above the horizon. At a solar longitude of 138.7 degrees, the season on Mars is Northern Summer.
NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Mars Reconnaissance Orbiter for NASA's Science Mission Directorate, Washington. Lockheed Martin Space Systems, Denver, is the prime contractor for the project and built the spacecraft. The High Resolution Imaging Science Experiment is operated by the University of Arizona, Tucson, and the instrument was built by Ball Aerospace and Technology Corp., Boulder, Colo.
Image Credit:
NASA/JPL/Univ. of Arizona
Image Addition Date:
2007-01-24
Edited Mars Reconnaissance Orbiter image of a candidate landing site for the Mars 2020 rover. Two images of the same general area were taken, probably to derive a 3D stereo pair to look for obnoxious boulders that may make a mess of things upon landing.
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.
Edited Mars Reconnaissance Orbiter image of shadows cast by the wall of the caldera of Olympus Mons.
Edited Mars Reconnaissance Orbiter PR image of colorful streaks running down a crater on Mars. Color/processing variant.
Edited Mars Reconnaissance Orbiter PR image of the back shield and parachute the slowed Perseverance down to landing speeds, on the ground in Jezero Crater. Color/processing variant.
Image source: photojournal.jpl.nasa.gov/catalog/PIA24336
Original caption: The High Resolution Imaging Experiment (HiRISE) camera aboard NASA's Mars Reconnaissance Orbiter (MRO) was able to capture this image of the final location of the parachute that helped slow down NASA's Perseverance rover during its landing on the surface of Mars. It is a close-up version of a larger image showing several parts of the Mars 2020 mission landing system that got the rover safely on the ground, PIA24333. The image was taken on Feb. 19, 2021.
These close-ups were processed to make them easier to see. The insets showing the descent stage and parachute have had color added and include data from the infrared band of light.
MRO's mission is managed by NASA's Jet Propulsion Laboratory, a division of Caltech in Pasadena, California, for NASA's Science Mission Directorate. Lockheed Martin Space in Denver, built the spacecraft. The University of Arizona provided and operates the High Resolution Imaging Experiment (HiRISE).
A key objective for Perseverance's mission on Mars is astrobiology, including the search for signs of ancient microbial life. The rover will characterize the planet's geology and past climate, pave the way for human exploration of the Red Planet, and be the first mission to collect and cache Martian rock and regolith (broken rock and dust).
Subsequent NASA missions, in cooperation with ESA (European Space Agency), would send spacecraft to Mars to collect these sealed samples from the surface and return them to Earth for in-depth analysis.
The Mars 2020 Perseverance mission is part of NASA's Moon to Mars exploration approach, which includes Artemis missions to the Moon that will help prepare for human exploration of the Red Planet.
NASA's Jet Propulsion Laboratory, which is managed for NASA by Caltech in Pasadena, California, built and manages operations of the Perseverance rover.
For more about Perseverance: mars.nasa.gov/mars2020/
Image Credit:
NASA/JPL-Caltech/University of Arizona
Image Addition Date:
2021-02-22
Edited Mars Reconnaissance Orbiter PR image of dark (even darker after I got a hold of the image) streaks down a slope on Mars.
Image source: photojournal.jpl.nasa.gov/catalog/PIA22240
Original caption: This image from NASA's Mars Reconnaissance Orbiter (MRO) shows streaks forming on slopes when dust cascades downhill. The dark streak is an area of less dust compared to the brighter and reddish surroundings. What triggers these avalanches is not known, but might be related to sudden warming of the surface.
These streaks are often diverted by the terrain they flow down. This one has split into many smaller streaks where it encountered minor obstacles.
These streaks fade away over decades as more dust slowly settles out of the Martian sky.
The map is projected here at a scale of 25 centimeters (9.8 inches) per pixel. [The original image scale is 28.1 centimeters (11.1 inches) per pixel (with 1 x 1 binning); objects on the order of 84 centimeters (33.1 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:
2018-02-05
Edited Mars Reconnaissance Orbiter image of "The Niagara Falls of Mars".
Image source: hirise.lpl.arizona.edu/ESP_050406_1585
Original caption: Various researchers are often pre-occupied with the quest for flowing water on Mars. However, in this image, we see one of many examples from Mars where lava (when it was molten) behaved in a similar fashion to liquid water.
In a 3D image from the Context Camera, we can see the northern rim of a 30-kilometer diameter crater situated in the western part of the Tharsis volcanic province. (See our own 3D image as well.) The image shows that a lava flow coming from the north-northeast surrounded the crater rim, and rose to such levels that it breached the crater rim at four locations to produce spectacular multi-level lava falls (one in the northwest and three in the north). These lava “falls” cascaded down the wall and terraces of the crater to produce a quasi-circular flow deposit. It seems that the flows were insufficient to fill or even cover the pre-existing deposits of the crater floor. This is evidenced by the darker-toned lavas that overlie the older, and possibly dustier, lighter-toned deposits on the crater floor.
Our image covers the three falls in the north-central region of the crater wall. The lava flows and falls are distinct as they are rougher than the original features that are smooth and knobby. In a close-up image the rough-textured lava flow to the north has breached the crater wall at a narrow point, where it then cascades downwards, fanning out and draping the steeper slopes of the wall in the process.
Now, if you’re thinking such as scene can only be observed on another planet, here’s a beautiful snapshot of lava falls from the 1969 Mauna Ulu eruption in Hawaii.
Written by: Eric Pilles and Livio L. Tornabene (26 June 2017)
This is a stereo pair with ESP_050472_1585.
Edited Mars Reconnaissance Orbiter image of a sediment lens in Jezero Crater. Jezero Crater is a possible landing spot for the Mars 2020 rover.
Edited Mars Reconnaissance Orbiter image of a scarp in Mars' north polar region. Processing variant.
Original caption: Sculpted Cool – This is part of a steep scarp within the North Polar layered deposits. Scarps like this have the potential for active avalanches.
NASA/JPL/University of Arizona (319 km above the surface, less than 10 km left to right.)
Edited Mars Reconnaissance Orbiter image of chains of spiders on the surface of Mars (where spiders are geologic formations, not real, live spiders with eight legs).
This dramatic view of the Maritian moon Phobos was acquired on 23 March 2008. This image was acquired at a distance of 6,800 kilometers from Phobos, providing a surface detail at 6.8 m/pixel scale. The impact crater Stickney is the largest feature on Phobos with a diameter of 9 km. The lineated textures on the walls of Stickney are landslides formed from materials falling into the crater interior in the weak Phobos gravity.
Edited Mars Reconnaissance Orbiter image of "The Niagara Falls of Mars".
Image source: hirise.lpl.arizona.edu/ESP_050406_1585
Original caption: Various researchers are often pre-occupied with the quest for flowing water on Mars. However, in this image, we see one of many examples from Mars where lava (when it was molten) behaved in a similar fashion to liquid water.
In a 3D image from the Context Camera, we can see the northern rim of a 30-kilometer diameter crater situated in the western part of the Tharsis volcanic province. (See our own 3D image as well.) The image shows that a lava flow coming from the north-northeast surrounded the crater rim, and rose to such levels that it breached the crater rim at four locations to produce spectacular multi-level lava falls (one in the northwest and three in the north). These lava “falls” cascaded down the wall and terraces of the crater to produce a quasi-circular flow deposit. It seems that the flows were insufficient to fill or even cover the pre-existing deposits of the crater floor. This is evidenced by the darker-toned lavas that overlie the older, and possibly dustier, lighter-toned deposits on the crater floor.
Our image covers the three falls in the north-central region of the crater wall. The lava flows and falls are distinct as they are rougher than the original features that are smooth and knobby. In a close-up image the rough-textured lava flow to the north has breached the crater wall at a narrow point, where it then cascades downwards, fanning out and draping the steeper slopes of the wall in the process.
Now, if you’re thinking such as scene can only be observed on another planet, here’s a beautiful snapshot of lava falls from the 1969 Mauna Ulu eruption in Hawaii.
Written by: Eric Pilles and Livio L. Tornabene (26 June 2017)
This is a stereo pair with ESP_050472_1585.
The Phlegra Dorsa region consists of ancient hills that have been surrounded and partially buried by flows from the Cerberus Fossae to the south. These flows could have been mud-laden water floods or very large lava flows.
The margin visible here is similar to that on lava flows that have had a long history of liquid lava being injected underneath the solidified crust.
Edited Mars Reconnaissance Orbiter image of sand dunes on Mars in the Meridiani Planum region. Context view.
Edited Mars Reconnaissance Orbiter PR image (also a context image) of broken up terrain in southern Aram Chaos. Processing variant.
Edited Mars Reconnaissance Orbiter image of an avalanche on a Martian north polar scarp exposing carbon dioxide frost that is falling down the scarp. The white spot in the dark layer is the falling carbon dioxide. Cropped and processed variant.
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 nice curves of flowing ejecta from impact craters on Mars.
This HiRISE image shows at least three isolated clouds of particles near a steep cliff in the northern polar region of Mars. These clouds, rolling or hovering close to the ground yet reaching up tens of meters high (up to 180 feet), are likely the result of an avalanche or fall of mostly carbon-dioxide frost. The frost clings to the scarp in the darkness of winter and may be disrupted by sunlight and thermal processes with the coming of spring. The cliff, approximately 700 meters high is made up of layers of water ice with varying dust content, roughly similar to the polar ice caps on Earth. ASU-IPF-3086
Edited Mars Reconnaissance Orbiter image of a crater with chlorides (salts) scattered about on Mars.
The High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter acquired this image of the Opportunity rover on the southwest rim of "Santa Maria" crater on New Year's Eve 2010, or Martian day (sol) 2466 of the rover's work on Mars. The rover is discernible at about the 8-o'clock position around the rim.
Opportunity is imaging the crater's interior to better reveal the geometry of rock layers as a means of defining the stratigraphy and the impact process. Santa Maria is a relatively young, 90-meter-diameter (295-foot-diameter) impact crater. Note the
Edited Mars Reconnaissance Orbiter PR image of Opportunity near Endeavour Crater. Opportunity hasn't responded since the start of the global dust storm (which is now mostly over). This image was taken on 20 September 2018. Color/processing variant.
Image source: photojournal.jpl.nasa.gov/catalog/PIA22549
Original caption: NASA's Opportunity rover appears as a blip in the center of this square. This image taken by HiRISE, a high-resolution camera onboard NASA's Mars Reconnaissance Orbiter, shows the dust storm over Perseverance Valley has substantially cleared.
The square highlighting Opportunity is just over a half-mile (1 kilometer) across (Figure 1). The image was taken Thursday, September 20, 2018, from about 166 miles (268 kilometers) above the surface.
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:
2018-09-25
Edited Mars Reconnaissance Orbiter PR image of part of Ladon Basin on Mars.
Image source: photojournal.jpl.nasa.gov/catalog/PIA22183
Original caption: Ladon Basin was a large impact structure that was filled in by the deposits from Ladon Valles, a major ancient river on Mars as seen in this image from NASA's Mars Reconnaissance Orbiter (MRO).
These wet sediments were altered into minerals such as various clay minerals. Clays imply chemistry that may have been favorable for life on ancient Mars, if anything lived there, so this could be a good spot for future exploration by rovers and perhaps return of samples to Earth.
The map is projected here at a scale of 50 centimeters (19.7 inches) per pixel. [The original image scale is 52.1 centimeters (20.5 inches) per pixel (with 2 x 2 binning); objects on the order of 156 centimeters (61.4 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:
2018-01-23
Edited Mars Reconnaissance Orbiter PR image of the remains of the Descent Stage and sky crane that lowered Perseverance to the floor of Jezero Crater after it flew off and crash landed in a dune field.
Image source: photojournal.jpl.nasa.gov/catalog/PIA24335
Original caption: The High Resolution Imaging Experiment (HiRISE) camera aboard NASA's Mars Reconnaissance Orbiter (MRO) was able to capture this image of the final location of the descent stage that helped fly NASA's Perseverance rover down to the surface of Mars. The image was taken on Feb. 19, 2021.
It is a close-up version of a larger image showing several parts of the Mars 2020 mission landing system that got the rover safely on the ground, PIA24333.
These close-ups of Mars 2020 hardware were processed to make them easier to see. The insets showing the descent stage and parachute have had color added and include data from the infrared band of light.
MRO's mission is managed by NASA's Jet Propulsion Laboratory, a division of Caltech in Pasadena, California, for NASA's Science Mission Directorate. Lockheed Martin Space in Denver, built the spacecraft. The University of Arizona provided and operates HiRISE.
A key objective for Perseverance's mission on Mars is astrobiology, including the search for signs of ancient microbial life. The rover will characterize the planet's geology and past climate, pave the way for human exploration of the Red Planet, and be the first mission to collect and cache Martian rock and regolith (broken rock and dust).
Subsequent NASA missions, in cooperation with ESA (European Space Agency), would send spacecraft to Mars to collect these sealed samples from the surface and return them to Earth for in-depth analysis.
The Mars 2020 Perseverance mission is part of NASA's Moon to Mars exploration approach, which includes Artemis missions to the Moon that will help prepare for human exploration of the Red Planet.
NASA's Jet Propulsion Laboratory, which is managed for NASA by Caltech in Pasadena, California, built and manages operations of the Perseverance rover.
For more about Perseverance: mars.nasa.gov/mars2020/
Image Credit:
NASA/JPL-Caltech/University of Arizona
Image Addition Date:
2021-02-22
Edited Mars Reconnaissance Orbiter image of sand dunes on Mars looking very blue (most likely due to contrasting colors of the bedrock and the filters used to take the images). Color/processing variant.
This map shows the route driven by NASA's Curiosity Mars rover from the location where it landed in August 2012 to its location in mid-November 2015, approaching examples of dunes in the "Bagnold Dunes" dune field.
The traverse line covers drives completed through the 1,165rd Martian day, or sol, of Curiosity's work on Mars (Nov. 15, 2015).
The base image for this map is from the High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter. North is up. The dark ground south of the rover's route is the Bagnold Dunes of dark, wind-blown material at the foot of Mount Sharp.
The scale bar at lower right represents two kilometers (1.2 miles).
Edited Mars Reconnaissance Orbiter image of dust devil tracks on sand dunes in Galle Carter (not "Gale" Crater) on Mars. Color/processing variant.
Edited Mars Reconnaissance Orbiter PR image of colors in the hills of Ganges Chasma on Mars. Color/processing variant.
The highly incised Martian gullies seen in the top image resemble gullies on Earth that are carved by liquid water. However, when the gullies are observed with the addition of mineralogical information (bottom), no evidence for alteration by water appears.
The pictured area spans about 2 miles (3 kilometers) on the eastern rim of Hale Crater. The High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter took the visible-light image. Color-coded compositional information added in the lower version comes from the same orbiter's Compact Reconnaissance Imaging Spectrometer for Mars (CRISM).
Color coding in light blue corresponds to surface composition of unaltered mafic material, of volcanic origin. Mafic material from the crater rim is carved and transported downslope along the gully channels. No hydrated minerals are observed within the gullies, in the data from CRISM, indicating limited interaction or no interaction of the mafic material with liquid water. These findings and related observations at about 100 other gully sites on Mars suggest that a mechanism not requiring liquid water may be responsible for carving these gullies on Mars. (Gullies on Mars are a different type of feature than seasonal dark streaks called recurring slope lineae or RSL; water in the form of hydrated salt has been identified at RSL sites.)
Shown in this image from NASA's Mars Reconnaissance Orbiter (MRO) are alluvial fans, fan-shaped deposits emerging from regions of steep topography. Alluvial fans on Mars are thought to be ancient and record past episodes of flowing water. This image shows part of one of those fans, which has been eroded.
The old stream channels now stand above the rest of the fan as ridges, mostly in the southern (bottom) part of the image. This can occur because the channel materials are more resistant to erosion; perhaps they had larger grains (gravel) or because minerals deposited from the water cemented together.
The map is projected here at a scale of 50 centimeters (19.7 inches) per pixel. [The original image scale is 52.4 centimeters (20.6 inches) per pixel (with 2 x 2 binning); objects on the order of 157 centimeters (61.8 inches) across are resolved.] North is up.