On the west (left) side of this image from NASA's Mars Reconnaissance Orbiter, fairly textbook-looking barchan sand dunes sit atop the bedrock. Barchan dunes pointing in the opposite direction are just a few kilometers away to the east.  In between these opposing barchan dunes are star dunes. Barchan dunes form when the sand-moving wind is fairly unidirectional. Star dunes, in contrast, form when the sand-moving wind comes from multiple directions -- not all at once, but from varying directions at different times of day or year.  Where is the sand coming from? As with most places on Mars...well, that's an area of on-going research. But the star dunes are telling us that this area seems to be accumulating sand.  https://photojournal.jpl.nasa.gov/catalog/PIA21934
Opposing Dunes, Opposing Winds
Dunes and more Dunes
Dunes and more Dunes
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Dunes
This view from the Mast Camera (Mastcam) on NASA's Curiosity Mars rover shows two scales of ripples, plus other textures, in an area where the mission examined a linear-shaped dune in the Bagnold dune field on lower Mount Sharp.  The scene is an excerpt from a 360-degree panorama acquired on March 24 and March 25, 2017, (PST) during the 1,647th Martian day, or sol, of Curiosity's work on Mars, at a location called "Ogunquit Beach."  Crests of the longer ripples visible in the dark sand of the dune are several feet (a few meters) apart. This medium-scale feature in active sand dunes on Mars was one of Curiosity's findings at the crescent-shaped dunes that the rover examined in late 2015 and early 2016. Ripples that scale are not seen on Earth's sand dunes. Overlaid on those ripples are much smaller ripples, with crests about ten times closer together.  Textures of the local bedrock in the foreground -- part of the Murray formation that originated as lakebed sediments -- and of gravel-covered ground (at right) are also visible. The image has been white-balanced so that the colors of the colors of the rock and sand materials resemble how they would appear under daytime lighting conditions on Earth.   https://photojournal.jpl.nasa.gov/catalog/PIA11242
Textures Where Curiosity Rover Studied a Martian Dune
Restoration efforts are underway to the dunes at the north beaches at NASA’s Kennedy Space Center in Florida on Oct. 8, 2018. About 450,000 cubic yards of beach-quality sand, tested for compatibility, is being transported to the space center’s beaches. One the dune is built up, native coastal vegetation will be replanted, helping to stabilize the dune and offer a habitat for Kennedy’s coast wildlife. Dunes are affected by beach erosion and storm surge from tropical events, such as hurricanes. Restoration began in spring 2018 and is targeted to be completed by April 2019.
Dune Restoration - October 2018
Restoration efforts are underway to the dunes at the north beaches at NASA’s Kennedy Space Center in Florida on Oct. 8, 2018. About 450,000 cubic yards of beach-quality sand, tested for compatibility, is being transported to the space center’s beaches. One the dune is built up, native coastal vegetation will be replanted, helping to stabilize the dune and offer a habitat for Kennedy’s coast wildlife. Dunes are affected by beach erosion and storm surge from tropical events, such as hurricanes. Restoration began in spring 2018 and is targeted to be completed by April 2019.
Dune Restoration - October 2018
Restoration efforts are underway to the dunes at the north beaches at NASA’s Kennedy Space Center in Florida on Oct. 8, 2018. About 450,000 cubic yards of beach-quality sand, tested for compatibility, is being transported to the space center’s beaches. One the dune is built up, native coastal vegetation will be replanted, helping to stabilize the dune and offer a habitat for Kennedy’s coast wildlife. Dunes are affected by beach erosion and storm surge from tropical events, such as hurricanes. Restoration began in spring 2018 and is targeted to be completed by April 2019.
Dune Restoration - October 2018
Restoration efforts are underway to the dunes at the north beaches at NASA’s Kennedy Space Center in Florida on Oct. 8, 2018. About 450,000 cubic yards of beach-quality sand, tested for compatibility, is being transported to the space center’s beaches. One the dune is built up, native coastal vegetation will be replanted, helping to stabilize the dune and offer a habitat for Kennedy’s coast wildlife. Dunes are affected by beach erosion and storm surge from tropical events, such as hurricanes. Restoration began in spring 2018 and is targeted to be completed by April 2019.
Dune Restoration - October 2018
Restoration efforts are underway to the dunes at the north beaches at NASA’s Kennedy Space Center in Florida on Oct. 8, 2018. About 450,000 cubic yards of beach-quality sand, tested for compatibility, is being transported to the space center’s beaches. One the dune is built up, native coastal vegetation will be replanted, helping to stabilize the dune and offer a habitat for Kennedy’s coast wildlife. Dunes are affected by beach erosion and storm surge from tropical events, such as hurricanes. Restoration began in spring 2018 and is targeted to be completed by April 2019.
Dune Restoration - October 2018
Native vegetation is being planted in a portion of the restored dunes at the north beaches at NASA’s Kennedy Space Center in Florida on Oct. 8, 2018. About 450,000 cubic yards of beach-quality sand, tested for compatibility, is being transported to the space center’s beaches. Once the dune is built up, native vegetation will be replanted, helping to stabilize the dune and offer a habitat for Kennedy’s coast wildlife. Dunes are affected by beach erosion and storm surge from tropical events, such as hurricanes. Restoration began in spring 2018 and is targeted to be completed by April 2019.
Dune Restoration - October 2018
Restoration efforts are underway to the dunes at the north beaches at NASA’s Kennedy Space Center in Florida on Oct. 8, 2018. About 450,000 cubic yards of beach-quality sand, tested for compatibility, is being transported to the space center’s beaches. One the dune is built up, native coastal vegetation will be replanted, helping to stabilize the dune and offer a habitat for Kennedy’s coast wildlife. Dunes are affected by beach erosion and storm surge from tropical events, such as hurricanes. Restoration began in spring 2018 and is targeted to be completed by April 2019.
Dune Restoration - October 2018
Restoration efforts are underway to the dunes at the north beaches at NASA’s Kennedy Space Center in Florida on Oct. 8, 2018. About 450,000 cubic yards of beach-quality sand, tested for compatibility, is being transported to the space center’s beaches. Once the dune is built up, native coastal vegetation will be replanted, helping to stabilize the dune and offer a habitat for Kennedy’s coast wildlife. Dunes are affected by beach erosion and storm surge from tropical events, such as hurricanes. Restoration began in spring 2018 and is targeted to be completed by April 2019.
Dune Restoration - October 2018
Restoration efforts are underway to the dunes at the north beaches at NASA’s Kennedy Space Center in Florida on Oct. 8, 2018. About 450,000 cubic yards of beach-quality sand, tested for compatibility, is being transported to the space center’s beaches. Once the dune is built up, native coastal vegetation will be replanted, helping to stabilize the dune and offer a habitat for Kennedy’s coast wildlife. Dunes are affected by beach erosion and storm surge from tropical events, such as hurricanes. Restoration began in spring 2018 and is targeted to be completed by April 2019.
Dune Restoration - October 2018
Restoration efforts are underway to the dunes at the north beaches at NASA’s Kennedy Space Center in Florida on Oct. 8, 2018. About 450,000 cubic yards of beach-quality sand, tested for compatibility, is being transported to the space center’s beaches. Once the dune is built up, native coastal vegetation will be replanted, helping to stabilize the dune and offer a habitat for Kennedy’s coast wildlife. Dunes are affected by beach erosion and storm surge from tropical events, such as hurricanes. Restoration began in spring 2018 and is targeted to be completed by April 2019.
Dune Restoration - October 2018
This image of Rabe Crater and the region around it was collected using the IR (infrared) camera. The brighter the material, the warmer the surface is. Most dunes on Mars are dark in visible wavelengths and bright in infrared. The majority of large craters in the southern hemisphere contain dunes on the crater floor.  Orbit Number: 67144 Latitude: -46.329 Longitude: 34.079 Instrument: IR Captured: 2017-02-01 12:57  http://photojournal.jpl.nasa.gov/catalog/PIA21519
Rabe Dunes in IR
Native vegetation is being planted in a portion of the restored dunes at the north beaches at NASA’s Kennedy Space Center in Florida on Oct. 8, 2018. About 450,000 cubic yards of beach-quality sand, tested for compatibility, is being transported to the space center’s beaches. One the dune is built up, native coastal vegetation will be replanted, helping to stabilize the dune and offer a habitat for Kennedy’s coast wildlife. Dunes are affected by beach erosion and storm surge from tropical events, such as hurricanes. Restoration began in spring 2018 and is targeted to be completed by April 2019.
Dune Restoration - October 2018
Dark Dunes Over-riding Bright Dunes
Dark Dunes Over-riding Bright Dunes
Dunes Galore
Dunes Galore
Dunes in Twilight
Dunes in Twilight
Bright Dunes
Bright Dunes
Polar Dunes
Polar Dunes
Kaiser Dunes
Kaiser Dunes
Dunes and Channel
Dunes and Channel
Argyre Dunes
Argyre Dunes
Swimming in Dunes
Swimming in Dunes
Ripples or Dunes?
Ripples or Dunes?
Dunes with Frost
Dunes with Frost
Dunes on a Ridge
Dunes on a Ridge
Argyre Dunes
Argyre Dunes
Barchan Dunes
Barchan Dunes
Polar Dunes
Polar Dunes
Groovy Dunes
Groovy Dunes
Crater Dunes
Crater Dunes
Copernicus Dunes
Copernicus Dunes
Dunes on Ice
Dunes on Ice
Herschel Dunes
Herschel Dunes
Bunge Dunes
Bunge Dunes
Dune Variety
Dune Variety
Dunes in Hellas
Dunes in Hellas
Intracrater Dunes
Intracrater Dunes
Marching Dunes
Marching Dunes
Rippled Dune
Rippled Dune
Crater Dunes
Crater Dunes
Crater Dunes
Crater Dunes
Dunes in Brashear
Dunes in Brashear
Rabe Dunes
Rabe Dunes
Lyot Dunes
Lyot Dunes
Frosty Dunes
Frosty Dunes
Everywhere Dunes
Everywhere Dunes
Dunes of Herschel
Dunes of Herschel
Noachis Dunes
Noachis Dunes
Arkhangelsky Dunes
Arkhangelsky Dunes
Dunes and Gullies
Dunes and Gullies
Dunes in Noachis
Dunes in Noachis
Polar Dunes
Polar Dunes
Frost on Dunes
Frost on Dunes
Bright Dunes
Bright Dunes
Dunes in Graben
Dunes in Graben
Martian Dunes
Martian Dunes
Windblown Dunes
Windblown Dunes
Russell Dunes
Russell Dunes
Fractures & Dunes
Fractures & Dunes
Argyre Dunes
Argyre Dunes
Richardson Dunes
Richardson Dunes
Southern Dunes
Southern Dunes
Dunes and Gullies
Dunes and Gullies
Caterpillar Dunes
Caterpillar Dunes
Dunes in Noachis
Dunes in Noachis
Dunes on the Move
Dunes on the Move
Copernicus Dunes
Copernicus Dunes
Herschel Dunes
Herschel Dunes
Polar Dunes
Polar Dunes
Springtime for Dunes
Springtime for Dunes
Frosty Dunes
Frosty Dunes
Crater Dunes
Crater Dunes
Polar Dunes
Polar Dunes
Dune-tastic
Dune-tastic