Tag Archives: barchan dunes

HiRISE: Finding the plume

Finding the plume. We hope to determine source and identity of a unique material emission “plume” from inside a corner of this crater, which is being dispersed 60-plus miles “downwind” from this location. HiRISE Picture of the Day archive. [More … Continue reading

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HiRISE: McLaughlin Crater dunes

McLaughlin Crater dunes. This image is part of a seasonal monitoring campaign to detect changes and quantify migration rates of the dunes in McLaughlin Crater. McLaughlin is one of the deepest craters on Mars, and was named after Dean B. … Continue reading

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HiRISE: Dune footprints in Hellas Planitia

These curious chevron shapes in southeast Hellas Planitia are the result of a complex story of dunes, lava, and wind. Long ago, there were large crescent-shaped (barchan) dunes that moved across this area, and at some point, there was an … Continue reading

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HiRISE: A first look at dunes

This image shows us a cross-section of a dune field. Dune shape depends on several factors, including the amount of sand present and the local wind directions. This dune field displays several distinct dune morphologies. We see both individual barchan-like … Continue reading

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Seeing Mars in a grain of sand

[Ed. note: The following is a guide to two recent special issues of the Journal of Geophysical Research; both collect papers reporting on studies of the Bagnold Dunes in Gale Crater. The guide complements the MSL report posted earlier here.] … Continue reading

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‘Ghost dune’ pits discovered on Mars

Scientists have discovered hundreds of crescent-shaped pits on Mars where sand dunes the size of the U.S. Capitol stood billions of years ago. The curves of these ancient dune impressions record the direction of prevailing winds on the Red Planet, … Continue reading

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HiRISE: Once in a blue dune

Sand dunes often accumulate in the floors of craters. In this region of Lyot Crater there is a field of classic barchan dunes. Just to the south of the group of barchan dunes is one large dune with a more … Continue reading

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HiRISE: Barchan Pac-Man

Barchan sand dunes are common on Mars and often form vast dune fields within very large (tens to hundreds of kilometers) impact basins. The regions upwind of barchans are usually devoid of sandy bedforms, so if you were walking in … Continue reading

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THEMIS: Frost-free dunes in north polar sand sea

THEMIS Image of the Day, March 16, 2018. This VIS image was collected at the height of summer. It is during this season that winds are able to move sand sized particles, slowly modifying the dunes. Olympia Undae is a … Continue reading

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THEMIS: Dunes in transition

THEMIS Image of the Day, March 15, 2018. This VIS image highlights the dune form/dune density aspects of Olypmia Undae. In the center there is a brighter, diagonal region of few dunes. These dunes are the arc or crescent shape … Continue reading

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