Light-Toned Rocks at Coprates Chasma

Coprates Chasma exposes several kilometers of rock that tell scientists about processes that occurred in the ancient past and in the subsurface. In this HiRISE image, rocks that display several colors and brightness are visible along the chasma wall.

Some of the brighter rocks could be minerals that formed when basaltic rock was altered by water flowing deep underground a long time ago before the chasma opened up. Alternatively, the light-toned rocks may be sediments that were deposited when water filled up portions of the chasma.

Dark dunes that could still be active are at the bottom of the image, attesting to more recent activity in this location.

This is a stereo pair with ESP_025441_1650.

Photo credit: NASA/JPL/University of Arizona

Phobos Anaglyph

Mars Express HRSC (High Resolution Stereo Camera) image of Phobos taken on 9 January 2011 at a distance of 100 km with a resolution of 8.1 m/pixel. Use red-blue glasses to fully appreciate this image.

Phobos is approximately 27 × 22 × 18 km and orbits Mars at a distance of 6000 km above the planet’s surface, or 9400 km from the center of the planet.

Photo credit: ESA/DLR/FU Berlin (G. Neukum)

Exposed Clasts in Gale Crater

This color image from NASA's Curiosity rover shows an area excavated by the blast of the Mars Science Laboratory's descent stage rocket engines. This is part of a larger, high-resolution color mosaic made from images obtained by Curiosity's Mast Camera.

With the loose debris blasted away by the rockets, details of the underlying materials are clearly seen. Of particular note is a well-defined, topmost layer that contains fragments of rock embedded in a matrix of finer material. Shown in the inset in the figure are pebbles up to 1.25 inches (about 3 centimeters) across (upper two arrows) and a larger clast 4 inches (11.5 centimeters) long protruding up by about 2 inches (10 centimeters) from the layer in which it is embedded. Clast-rich sedimentary layers can form in a number of ways. Their mechanisms of formation can be distinguished by the size, shape, surface textures and positioning with respect to each other of the fragments in the layers.

The images in this mosaic were acquired by the 34-millimeter Mastcam over about an hour of time on August 8, 2012 PDT (Aug. 9, 2012 EDT), each at 1,200 by 1,200 pixels in size.

In the main version, the colors portrayed are unmodified from those returned by the camera. The view is what a cell phone or camcorder would record since the Mastcam takes color pictures in the exact same manner that consumer cameras acquire color images. The second version (Figure 1), shows the colors modified as if the scene were transported to Earth and illuminated by terrestrial sunlight. This processing, called "white balancing," is useful for scientists to be able to recognize and distinguish rocks by color in more familiar lighting.

Photo credit: NASA/JPL-Caltech/MSSS

Sigli and Shambe Craters

This computer-generated perspective view was created using data obtained from the High-Resolution Stereo Camera (HRSC) on ESA’s Mars Express. Centered at around 18°S and 329°E, this image has a ground resolution of about 20 m per pixel. Sigli and Shambe dominate this image, which highlights the deep fracturing within the crater walls. The shape of the craters leads scientists to believe they were formed from the same impactor, which fragmented into two pieces just before hitting Mars.

Image credit: ESA/DLR/FU Berlin (G. Neukum)

Gale Crater's Rim

This color image from NASA's Curiosity rover shows part of the wall of Gale Crater, the location on Mars where the rover landed on August 5, 2012 PDT (August 6, 2012 EDT). This is part of a larger, high-resolution color mosaic made from images obtained by Curiosity's Mast Camera.

This image of the crater wall is north of the landing site, or behind the rover. Here, a network of valleys believed to have formed by water erosion enters Gale Crater from the outside. This is the first view scientists have had of a fluvial system -- one relating to a river or stream -- from the surface of Mars. Known and studied since the 1970s beginning with NASA's Viking missions, such networks date from a period in Martian history when water flowed freely across the surface. The main channel deposit seen here resembles a dirt road ascending into the mountains, which are actually the north wall and rim of Gale Crater. The colors in a second version (Figure 1) have been modified as if the scene were transported to Earth and illuminated by terrestrial sunlight. This processing, called "white balancing," is useful for scientists to be able to recognize and distinguish rocks by color in more familiar lighting.

Although Curiosity is about 11 miles (18 kilometers) away from this area and the view is obscured somewhat by dust and haze, the image provides new insights into the style of sediment transport within this system. Curiosity has no current plans to visit this valley system, since the primary objective of the rover is south of the landing site. But images taken later and with the 100-millimeter Mastcam are likely to allow scientists to study the area in significantly more detail.

The images in this mosaic were acquired by the 34-millimeter MastCam over about an hour of time on August 8, 2012 PDT (Aug. 9, 2012 EDT), each at 1,200 by 1,200 pixels in size.

Photo credit: NASA/JPL-Caltech/MSSS

Landing Accuracy on Mars: An Historical Perspective

This image illustrates how spacecraft landings on Mars have become more and more precise over the years. Since NASA's first Mars landing of Viking in 1976, the targeted landing regions, or ellipses, have shrunk. Improvements in interplanetary navigation tightened the ellipses between the 1997 and 2008 landings of NASA's Pathfinder and Phoenix.

NASA's Curiosity used those improvements, in addition to hypersonic guided entry similar to that used by astronauts returning to Earth during NASA's Apollo program, to further reduce the ellipse size and land just north of the slopes of Mount Sharp. The area of Curiosity's landing ellipse was just seven percent the size of the previous best landing ellipse for Phoenix. This guided entry technique also allowed a much heavier rover to land on Mars.

The background picture is from the European Space Agency's Mars Express overlaid with topographical data from NASA's Mars Global Surveyor.

Image credit: NASA/JPL-Caltech/ESA

Curiosity's Deck

This full-resolution self-portrait shows the deck of NASA's Curiosity rover from the rover's Navigation cameras. The back of the rover can be seen at the top left of the image, and two of the rover's right side wheels can be seen on the left. Part of the pointy rim of Gale Crater forms the lighter color strip in the background. Bits of gravel, about 0.4 inches (1 centimeter) in size, are visible on the deck of the rover.

This mosaic is made of eight images, each of 1,024 by 1,024 pixels, taken late at night on August 7 PDT (early morning August 8 EDT). It uses an average of the Navcam positions to synthesize the point of view of a single camera, with a field of view of 120 degrees. Seams between the images have been minimized, but a few are still visible. The wide field of view introduces some distortion at the edges of the mosaic.

The "augmented reality" or AR tag seen in the middle of the image can be used in the future with smart phones to obtain more information about the mission.

This full-resolution image shows part of the deck of NASA's Curiosity rover taken from one of the rover's Navigation cameras looking toward the back left of the rover.

On the left of this image, part of the rover's power supply is visible. To the right of the power supply can be seen the pointy low-gain antenna and side of the paddle-shaped high-gain antenna for communications directly to Earth. The rim of Gale Crater is the lighter colored band across the horizon. The effects of the descent stage's rocket engines blasting the ground can be seen on the right side of the image, next to the rover.

This full-resolution image is 1,024 by 1,024 pixels. The image was taken on August 7 PDT (August 8 EDT).

Photo credit: (1) NASA/JPL-Caltech; (2) NASA/JPL-Caltech

Gale Crater Panorama

This is the first 360-degree panorama in color of the Gale Crater landing site taken by NASA's Curiosity rover. The panorama was made from thumbnail versions of images taken by the Mast Camera.

Scientists will be taking a closer look at several splotches in the foreground that appear gray. These areas show the effects of the descent stage's rocket engines blasting the ground. What appeared as a dark strip of dunes in previous, black-and-white pictures from Curiosity can also be seen along the top of this mosaic, but the color images also reveal additional shades of reddish brown around the dunes, likely indicating different textures or materials.

The images were taken late August 8 PDT (August 9 EDT) by the 34-millimeter Mast Camera. This panorama mosaic was made of 130 images of 144 by 144 pixels each. Selected full frames from this panorama, which are 1,200 by 1,200 pixels each, are expected to be transmitted to Earth later. The images in this panorama were brightened in the processing. Mars only receives half the sunlight Earth does and this image was taken in the late Martian afternoon.

Photo credit: NASA/JPL-Caltech/MSSS

Note: For more information, see NASA's Curiosity Beams Back a Color 360 of Gale Crater.

Yellowknife Quadrangle

This image shows the quadrangle where NASA's Curiosity rover landed, now called Yellowknife. The mission's science team has divided the landing region into several square quadrangles, or quads, of interest about 1-mile (1.3-kilometers) wide. This will allow groups of team members to focus their analysis on a particular part of the surface.

Yellowknife is a city in northwestern Canada and a group of rocks from the same region. The rocks were formed 2.7 billion years ago from both volcanoes and sediments laid down by water, and were deposited over 4-billion-year-old rocks, the oldest known on Earth.

The image was obtained by the High-Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter.

Photo credit: NASA/JPL-Caltech/University of Arizona

Gale Crater by Curiosity

These are the first two full-resolution images of the Martian surface from the Navigation cameras on NASA's Curiosity rover, which are located on the rover's "head" or mast. The rim of Gale Crater can be seen in the distance beyond the pebbly ground.

The topography of the rim is very mountainous due to erosion. The ground seen in the middle shows low-relief scarps and plains. The foreground shows two distinct zones of excavation likely carved out by blasts from the rover's descent stage thrusters.

These are full-resolution images, 1024 by 1024 pixels in size.

Photo credit: NASA/JPL-Caltech

Note: For more information, see First 360-Degree Panorama From NASA's Curiosity Mars Rover. For the full 360-degree panorama (which is mostly made up of fuzzy thumbnail photos, see PIA16011: Curiosity Takes It All In.

Curiosity's First Self-Portrait

This Picasso-like self portrait of NASA's Curiosity rover was taken by its Navigation cameras, located on the now-upright mast. The camera snapped pictures 360-degrees around the rover, while pointing down at the rover deck, up and straight ahead. Those images are shown here in a polar projection. Most of the tiles are thumbnails, or small copies of the full-resolution images that have not been sent back to Earth yet. Two of the tiles are full-resolution.

Photo credit: NASA/JPL-Caltech

3D Topographical Map of Gale Crater

Gale Crater is 154 km wide and is located at latitude 5.4 degrees south and longitude 137.9 degrees east. This image, taken by the High Resolution Stereo Camera (HRSC) of Mars Express, has a resolution of 100 meters per pixel. It is color-coded based on a digital terrain model derived from stereo image data.

Map credit: ESA/DLR/FU Berlin (G. Neukum)

Curiosity's Heat Shield Falling

This color full-resolution image showing the heat shield of NASA's Curiosity rover was obtained during descent to the surface of Mars on August 5 PDT (August 6 EDT). The image was obtained by the Mars Descent Imager instrument known as MARDI and shows the 15-foot (4.5-meter) diameter heat shield when it was about 50 feet (16 meters) from the spacecraft.

This image shows the inside surface of the heat shield, with its protective multi-layered insulation. The bright patches are calibration targets for MARDI. Also seen in this image is the Mars Science Laboratory Entry, Descent, and Landing Instrument (MEDLI) hardware attached to the inside surface.

At this range, the image has a spatial scale of 0.4 inches (1 cm) per pixel. It is the 36th MARDI image, obtained about three seconds after heat shield separation and about two and one-half minutes before touchdown. The original image from MARDI has been geometrically corrected to look flat. The thumbnail version of this image is available at PIA15988.

Curiosity landed inside of a crater known as Gale Crater.

Photo credit: NASA/JPL-Caltech

Note: For more information, see New Mars Rover Beams Back Images Showing its Descent. Below is Curiosity's own video of the descent.


Video credit: NASA/JPL-Caltech/MSSS

Martian Dust Storm Over Utopia Planitia

This close-up image of a dust storm on Mars was acquired by the Mars Color Imager instrument on NASA's Mars Reconnaissance Orbiter on November 7, 2007, around 3 p.m. local time on Mars. Scientists working with NASA's Curiosity rover, which is set to land on Mars on Aug. 5 PDT (August 6 EDT), are monitoring Mars each day for similar small storms that could either drift over the landing site or stir up dust that moves as haze over the site.

This image is centered on Utopia Planitia (53.6 degrees north latitude, 147.9 degrees east longitude), along the north seasonal polar cap edge in late northern winter. When NASA's Curiosity rover lands on Mars, it will be late southern winter. Scientists are looking at similar small storms that form near the south seasonal polar cap edge. The dust storm pictured here was short-lived, lasting less than 24 hours. The image also shows the seasonal north polar cap (at top of figure) and gravity-wave water ice clouds coming off of Mie crater, just south of the storm. Gravity-wave clouds, also called lee-wave clouds, are clouds that result from changes in atmospheric pressure, temperature and height because of vertical displacement, such as when wind blows over a mountain or crater wall.

The projection of the image is polar stereographic and the image has a resolution of about 0.6 miles (1 kilometer) per pixel. North is indicated with an arrow in this image. The white scale bar is 93 miles (150 kilometers).

Photo credit: NASA/JPL-Caltech/MSSS

Note: Obviously the text for this photo was written prior to Curiosity's landing; however, due to the deluge of new photos coming in, I decided to push this blog post back to give priority to some of the other, more important stories.

Curiosity's Landing Site

The four main pieces of hardware that arrived on Mars with NASA's Curiosity rover were spotted by NASA's Mars Reconnaissance Orbiter (MRO). The High-Resolution Imaging Science Experiment (HiRISE) camera captured this image about 24 hours after landing. The large, reduced-scale image points out the strewn hardware: the heat shield was the first piece to hit the ground, followed by the back shell attached to the parachute, then the rover itself touched down, and finally, after cables were cut, the sky crane flew away to the northwest and crashed. Relatively dark areas in all four spots are from disturbances of the bright dust on Mars, revealing the darker material below the surface dust.

Around the rover, this disturbance was from the sky crane thrusters, and forms a bilaterally symmetrical pattern. The darkened radial jets from the sky crane are downrange from the point of oblique impact, much like the oblique impacts of asteroids. In fact, they make an arrow pointing to Curiosity.

This image was acquired from a special 41-degree roll of MRO, larger than the normal 30-degree limit. It rolled towards the west and towards the sun, which increases visible scattering by atmospheric dust as well as the amount of atmosphere the orbiter has to look through, thereby reducing the contrast of surface features. Future images will show the hardware in greater detail. Our view is tilted about 45 degrees from the surface (more than the 41-degree roll due to planetary curvature), like a view out of an airplane window. Tilt the images 90 degrees clockwise to see the surface better from this perspective. The views are primarily of the shadowed side of the rover and other objects.

The Curiosity rover is approximately 4,900 feet (1,500 meters) away from the heat shield; about 2,020 feet (615 meters) away from the parachute and back shell; and approximately 2,100 feet (650 meters) away from the discoloration consistent with the impact of the sky crane.

The image scale is 39 centimeters (15.3 inches) per pixel.

Photo credit: NASA/JPL-Caltech/University of Arizona

Note: For more information, see Orbiter Images NASA's Martian Landscape Additions.

Fresh Impact Crater North of Coprates Chasma

This image shows a fresh impact crater about 2 kilometer (1.2 miles) across. How do we know it is fresh?

The crater walls are steep and rocky, and fine striated texture is still visible on the ejecta. Over time, erosion and dust settling out of the atmosphere will smooth out such details. However, these processes are slow on Mars, and the crater is probably at least several million years old.

Craters like this are important targets for HiRISE for several reasons. The details of the fresh crater are interesting in themselves for studying impact processes, but crater walls can also provide great exposures of bedrock. The steep slopes are also good places to look for active processes like rockfalls happening today, especially when we can compare a series of images taken over several years.

Photo credit: NASA/JPL/University of Arizona

Curiosity Descending Into Gale Crater

NASA's Curiosity rover and its parachute were spotted by NASA's Mars Reconnaissance Orbiter as Curiosity descended to the surface on August 5 PDT (August 6 EDT). The High-Resolution Imaging Science Experiment (HiRISE) camera captured this image of Curiosity while the orbiter was listening to transmissions from the rover. Curiosity and its parachute are in the center of the white box; the inset image is a cutout of the rover stretched to avoid saturation. The rover is descending toward the etched plains just north of the sand dunes that fringe "Mt. Sharp." From the perspective of the orbiter, the parachute and Curiosity are flying at an angle relative to the surface, so the landing site does not appear directly below the rover.

The parachute appears fully inflated and performing perfectly. Details in the parachute, such as the band gap at the edges and the central hole, are clearly seen. The cords connecting the parachute to the back shell cannot be seen, although they were seen in the image of NASA's Phoenix lander descending, perhaps due to the difference in lighting angles. The bright spot on the back shell containing Curiosity might be a specular reflection off of a shiny area. Curiosity was released from the back shell sometime after this image was acquired.

This view is one product from an observation made by HiRISE targeted to the expected location of Curiosity about one minute prior to landing. It was captured in HiRISE CCD RED1, near the eastern edge of the swath width (there is a RED0 at the very edge). This means that the rover was a bit further east or downrange than predicted.

The image scale is 13.2 inches (33.6 centimeters) per pixel.

Photo credit: NASA/JPL-Caltech/Univ. of Arizona

Note: For more information, see NASA's Curiosity Rover Caught in the Act of Landing; also, NASA's Curiosity Rover Caught in the Act of Landing (same title, different page).

Ladon Valles

High-Resolution Stereo Camera (HRSC) nadir and colour channel data taken during revolution 10602 on 27 April 2012 by ESA’s Mars Express have been combined to form a natural-color view of the Ladon Valles region. Centered at around 18°S and 329°E, this image has a ground resolution of about 20 m per pixel. The image shows the interconnected craters Sigli and Shambe, believed to have formed when a large meteorite fragmented in to two pieces just before impact. Extensive fracturing can be seen within the craters. Above the craters (west), creek-like flow channels can be seen leading in to the wider impact basin region to the right (north).

Photo credit: ESA/DLR/FU Berlin (G. Neukum)

First Images from Curiosity

This image shows one of the first views from NASA's Curiosity rover, which landed on Mars the evening of August 5 PDT (early morning hours August 6 EDT). It was taken through a "fisheye" wide-angle lens on one of the rover's Hazard-Avoidance cameras. These engineering cameras are located at the rover's base. As planned, the early images are lower resolution. Larger color images are expected later in the week when the rover's mast, carrying high-resolution cameras, is deployed.

Photo credit: NASA/JPL-Caltech

This is one of the first images taken by NASA's Curiosity rover, which landed on Mars the evening of August 5 PDT (morning of August 6 EDT). It was taken through a "fisheye" wide-angle lens on the left "eye" of a stereo pair of Hazard-Avoidance cameras on the left-rear side of the rover. The image is one-half of full resolution. The clear dust cover that protected the camera during landing has been sprung open. Part of the spring that released the dust cover can be seen at the bottom right, near the rover's wheel.

On the top left, part of the rover's power supply is visible.

Some dust appears on the lens even with the dust cover off.

The cameras are looking directly into the sun, so the top of the image is saturated. Looking straight into the sun does not harm the cameras. The lines across the top are an artifact called "blooming" that occurs in the camera's detector because of the saturation.

As planned, the rover's early engineering images are lower resolution. Larger color images from other cameras are expected later in the week when the rover's mast, carrying high-resolution cameras, is deployed.

Photo credit: NASA/JPL-Caltech

Notes: For more information on the lower photo see NASA's New Mars Rover Sends Higher-Resolution Image. Are these blueberries in the sand?

Cloudy with a chance of...

This global map of Mars was acquired on August 2, 2012, by the Mars Color Imager instrument on NASA's Mars Reconnaissance Orbiter. One global map is generated each day to forecast weather conditions for the entry, descent and landing of NASA's Curiosity rover. The active dust storm observed south of Curiosity's landing site on July 31 has dissipated, leaving behind a dust cloud that will not pose a threat to the landing.

The map is a rectangular projection of Mars (from 90 degrees latitude to minus 90 degrees latitude, and minus 180 degrees longitude to 180 degrees east longitude). The landing site is located on the right side of the map, near 137 degrees east longitude and 4.5 degrees south latitude. The map shows water ice clouds at equatorial latitudes that are typical for late southern winter, when Mars is farther from the sun. Along the southern (bottom) part of the map there are patches of orange clouds, indicating dust lofted into the atmosphere. Small, short-lived dust storms are common at this time of year on Mars and were taken into account when Curiosity's landing system was designed and tested. Larger and more long-lived dust storms are very rare at this time of year.

This global map of Mars was acquired on October 28, 2008, by the Mars Color Imager instrument on NASA's Mars Reconnaissance Orbiter. It was acquired during the same season that NASA's Curiosity rover will land in, but two Mars years earlier. It is remarkably free of water ice clouds when compared with the maps acquired this year in the days leading up to Curiosity's landing.

In 2008, during this season, the planet was dustier than usual. Larger amounts of dust cause sunlight to warm the atmosphere and make it less dense, which means less stopping power for a landing rover. What's more, dusty conditions can lead to an increased chance for small, intense dust storms, another challenge for rover landings. So far, the weather forecast for Curiosity calls for a clearer atmosphere; nonetheless, the spacecraft has been designed to land safely under conditions similar to those observed in 2008.

The map is a rectangular projection of Mars (from 90 degrees latitude to minus 90 degrees latitude, and minus 180 degrees longitude to 180 degrees east longitude). The landing site is located on the right side of the map, near 137 degrees east longitude and 4.5 degrees south latitude. Along the northern (top) and southern (bottom) parts of the map there are patches of orange clouds, indicating dust lofted into the atmosphere.

Map credit 1: NASA/JPL-Caltech/MSSS; map credit 2: NASA/JPL-Caltech/MSSS

Note: NASA has released an additional Martian weather map, that of August 5th, the day Curiosity landed in Gale Crater.

Nested Craters in Utopia Planitia

Impact craters that are only a few kilometers in size on Mars usually have simple bowl shaped interiors with craters in weaker material being larger than craters in stronger material.

Occasionally though, nature is more complicated and these simple rules don't apply. One such case is shown here where is appears as if there are craters nested within each other. These nested craters are probably caused by changes in the strength of the target material. This usually happens when a weaker material overlies a stronger material.

We can use craters like this to tell us something about what lies below the surface. What could be causing the change in strength in the subsurface? Mars has a lot of ice in its terrain near the surface. This ice-rich layer could be the weaker material and the deeper ice-free layer could be the stronger material.

Photo credit: NASA/JPL/University of Arizona

Regional Topography Map Around Gale Crater

Gale Crater on Mars, where NASA's Curiosity rover is set to land, belongs to a family of large, very old craters shown here on this elevation map. It has one of the lowest elevations among this family.

The data come from the Mars Orbiter Laser Altimeter instrument on NASA's Mars Global Surveyor.

Map credit: NASA/JPL-Caltech

Layers in Flammarion Crater

The objective of this observation is to examine layers. In and around this region, there are outcrops of layered terrain.

A high resolution image can see minute details that will enable us to start to catalog different types of layers and to discover under what conditions they are produced. In this particular image there is a cap rock on top of some poorly formed layers and some well formed layers.

Photo credit: NASA/JPL/University of Arizona

Magnetic Fields of Earth and Mars

This is an artist's concept comparing the present day magnetic fields on Earth and Mars. Earth's magnetic field is generated by an active dynamo -- a hot core of molten metal. The magnetic field surrounds Earth and is considered global (left image). The various Martian magnetic fields do not encompass the entire planet and are local (right image). The Martian dynamo is extinct, and its magnetic fields are "fossil" remnants of its ancient, global magnetic field.

Image credit: NASA/GSFC

Dunes on the Move in Lyot Crater

HiRISE has been carrying out a dedicated survey of sand dunes on Mars, determining whether and how fast the dunes move by observing repeatedly at intervals of Martian years. More than 60 sites have been monitored so far, showing that sand dunes from the equator to the poles are advancing at rates of up to 1 meter per Martian year.

These observations are still spotty, however, and tend to be concentrated in the tropics and the North Polar erg (the sand sea that surrounds the North Pole). One latitude band that had not been sampled at all lies between 30 and 65 degrees north. This observation is among a set of images acquired to fill that gap.

This image shows a variety of different dune types in southern Lyot Crater in the northern lowlands at 48.9 degrees North. Transverse dunes to the west grade into longitudinal dunes downwind to the east and barchans to the south, possibly because of local winds channeled by topography in the impact basin. This image was intended to match the approximate illumination and viewing conditions of an earlier HiRISE observation that was made two Martian years earlier, in August 2008.

Detailed comparison of the two images shows movement on many of the dunes during this interval of nearly four Earth years. The subimage is an animation showing changes on one of the small barchans in the south of the dune field. The area pictured in the subimage is about 100 meters across. Winds from the west (left) have shifted the small ripples up the back of the dune towards the east. Sand has blown over the crest of the dune, cascaded down the steep slip face, and accumulated along the base of the slip face in the lee of the dune. In this way, the small dune advances slowly downwind.

Other images also show dune activity in this latitude band, adding to a growing suspicion that dunes are on the move everywhere on Mars, faster in some places than others.

Photo credit: NASA/JPL/University of Arizona