Curiosity Nears Martian Bagnold Dunes in First Active Sand Dune Visit

Summary: NASA's Curiosity Mars rover nears Martian Bagnold Dunes in first active sand dune visit outside of Earth.

Bagnold Dunes are dark band in lower foreground; multiple-image view taken by Mast Camera (Mastcam) on NASA's Curiosity Mars rover on September 25, 2015; view toward south-southeast: NASA/JPL-Caltech/MSSS, Public Domain, via NASA Mars Exploration

As of Monday, Nov. 16, 2015, NASA’s Curiosity Mars rover is within 200 meters or yards of Dune 1 of the Martian Bagnold Dunes, a destination that will mark the first ever solar system study, outside of Earth, of an active, or mobile, sand dune.

At Dune 1, Curiosity is scheduled to collect external and internal samples for analysis by the rover’s internal laboratory instruments. Included in Curiosity’s Bagnold campaign is an investigation of wind-sorting versus water alteration as the natural process accounting for the rich presence of heavy-grained olivine in the dune field, which darkly edges the northwestern flank of Mount Sharp in Gale Crater.

“We will use Curiosity to learn whether the wind is actually sorting the minerals in the dunes by how the wind transports particles of different grain size,” notes Bethany Ehlmann, research scientist at the Jet Propulsion Laboratory, assistant professor of planetary science at the California Institute of Technology (Caltech), and co-head of the Bagnold campaign.

The dune field’s dark, rippled tops, darkened by basaltic rock, move from north to south. Images taken by the Mars Reconnaissance Orbiter, which has been taking high resolution images of the Martian surface since Sept. 29, 2006, reveal that, as active sand dunes, Mars’ Bagnold Dunes migrate southward as much as 3 feet (1 meter) per Earth year.

“These dunes have a different texture from dunes on Earth. The ripples on them are much larger than ripples on top of dunes on Earth, and we don’t know why. We have models based on the lower air pressure. It takes a higher wind speed to get a particle moving. But now we’ll have the first opportunity to make detailed observations,” explains Nathan Bridges, senior staff scientist at the Johns Hopkins University Applied Physics Laboratory and co-head of the Bagnold campaign.

The Martian Bagnold Dunes are named informally for British military engineer Ralph Bagnold, who pioneered the study of wind-transported sand in dunes. Bagnold’s Physics of Blown Sand and Desert Dunes, published in 1941 and still considered a classic reference, has informed NASA’s study of Martian sand dunes.

Mount Sharp, which rises above the Bagnold Dunes as Gale Crater’s central peak, is a layered, sedimentary mountain with unknown origins. While wind seems to have formed most of Mount Sharp, water appears to have deposited the mountain’s bottom layers.

Bethany Ehlmann states: “We’ve planned investigations that will not only tell us about modern dune activity on Mars but will also help us interpret the composition of sandstone layers made from dunes that turned into rock long ago.”

orbital view of dune that Curiosity will visit ~ view of Dune 1 covers an area about 1,250 feet (about 380 meters) across; image taken by NASA's Mars Reconnaissance Orbiter on Nov. 16, 2015: NASA/JPL-Caltech/Univ. of Arizona, Public Domain, via NASA Mars Exploration

Acknowledgment

My special thanks to talented artists and photographers/concerned organizations who make their fine images available on the internet.

Image credits:

orbital view of Dune 1: NASA/JPL-Caltech/Univ. of Arizona, Public Domain, via NASA Mars Exploration @ http://mars.jpl.nasa.gov/msl/multimedia/images/?ImageID=7541

Bagnold Dunes: NASA/JPL-Caltech/MSSS, Public Domain, via NASA Mars Exploration @ http://mars.jpl.nasa.gov/msl/multimedia/images/?ImageID=7539

For further information:

Kremer, Ken. "Curiosity Mars Rover Nears First Study Site Of Active Sand Dunes Beyond Earth." Universe Today.
Available @ http://www.universetoday.com/123469/curiosity-mars-rover-nears-first-study-site-of-active-sand-dunes-beyond-earth/

Marriner, Derdriu. "Curiosity Follows the Water on Mars to Ancient Lake in Gale Crater." Earth and Space News. Thursday, Oct. 29, 2015.
Available @ https://earth-and-space-news.blogspot.com/2015/10/curiosity-follows-water-on-mars-to.html

NASA JPL @NASAJPL. "Dark Dunes Ahead: @MarsCuriosity first craft to visit active dunes beyond Earth." Twitter. Nov. 16, 2015.
Available @ https://twitter.com/NASAJPL/status/666395936357134337

"Where is Curiosity?" NASA Jet Propulsion Laboratory Mars Exploration > Mission.
Available @ http://mars.jpl.nasa.gov/msl/mission/whereistherovernow/