Tag Archives: basaltic sand

THEMIS: Basaltic sands in Marth Crater

THEMIS Image of the Day, February 21, 2019. This false color image shows part of the floor of Marth Crater. Dark blue tones typically indicate basaltic sands. Wind action is blowing the sand and dust to the southern side of … Continue reading

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THEMIS: Pasteur Crater in false color

THEMIS Image of the Day, February 20, 2019. Today’s image shows part of the floor of Pasteur Crater. The deposit in the southwest part of the floor is a fill deposit that is undergoing erosion. Small sand dunes are found … Continue reading

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THEMIS: Herschel Crater floor in false color

THEMIS Image of the Day, February 19, 2019. This VIS image shows part of the floor of Herschel Crater. Sand dunes are visible at the bottom of the image. The dark blue in this false color image typically indicates basaltic … Continue reading

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THEMIS: Sand sheet in Halley Crater

THEMIS Image of the Day, December 24, 2018. This VIS image shows part of the dune field on the floor of Halley Crater. Rather than small individual sand dunes, the sand here is collected into a sand sheet and dune … Continue reading

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THEMIS: Active dune field in Noachis

THEMIS Image of the Day, December 13, 2018. Today’s VIS image shows sand dunes on the floor of an unnamed crater in Noachis Terra. These dunes are likely active because they are dark, indicating that they move often enough to … Continue reading

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THEMIS: Halley Crater dunes

THEMIS Image of the Day, December 6, 2018. Halley Crater is located on the western side of Argyre Planitia. Sand dunes cover part of the crater floor. The dunes’ dark tone indicates they are free from dust. This in turn … Continue reading

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HiRISE: Active dunes in Wirtz Crater

These gorgeous dunes are likely active, with ripples on their upwind slopes and dark streaks on their downwind slopes forming and changing due to wind-driven sand motion. This motion will also keep the dune brink (the edge between the two … Continue reading

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THEMIS: Active dunes in Noachis Terra

THEMIS Image of the Day, November 28, 2018. Today’s VIS image shows a sand sheet with surface dunes forms on the floor of an unnamed crater in Noachis Terra. Dark dunes indicate active dunes: Winds stir the sand, which kicks … Continue reading

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THEMIS: Dunes in Kaiser Crater

THEMIS Image of the Day, November 23, 2018. This VIS image shows part of the floor of Kaiser Crater, including several sand dunes. Kaiser Crater is located in Noachis Terra. The dunes’ dark tone indicates they are free of dust, … Continue reading

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Volcanic ash: Major source of Mars dust?

[Editor’s note: From a paper by Charlie Bristow and Torsten Moller, recently published in the Journal of Geophysical Research.] Dust Production by Abrasion of Eolian Basalt Sands: Analogue for Martian Dust • Collisions between particles and surfaces during eolian abrasion … Continue reading

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