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Nili Patera dune field

Nili Patera is a dune field on Mars. It is located on top of a lava bed, at the site of an ancient volcano, the Nili Patera caldera of Syrtis Major, near the Martian equator, and it is one of the most active dune fields of Mars. Its location coordinates on Mars are 8.7° N latitude, 67.3° E longitude. It is being actively studied by the HiRISE camera, on board the Mars Reconnaissance Orbiter, at the rate of one image every six weeks. The study of the movement of the dunes provides information regarding wind variation as a function of time and furthers the study of surface erosion characteristics of the Martian landscape. This information can then be used for the development and design of future Mars expeditions. The dunes of the Patera field are of the barchan type and their study by HiRISE was the first one to establish dune and ripple movement of a minimum of 1 metre on Mars. The Patera dune field, was also the first to be investigated using the COSI-Corr software, which was originally developed to analyse the movement of earthbound dunes. The research results from the evidence provided by the monitoring of the Nili Patera field, indicate sand fluxes of the order of several cubic metres per metre per year, similar to the flux observed at the sand dunes of Victoria Valley in Antarctica.

Investigation
Over a period of 35 years, starting with Mariner 9 and ending with Mars Odyssey, there had been no detection of sand movement on Mars. Such movement mechanism is called saltation and it has been determined that the dunes at Nili Patera, under the existing wind conditions, are active and moving as a unit. Due to the thinner atmosphere of Mars, winds have to be approximately 10 times faster than those on Earth to cause sand movement. These high winds occur very rarely on Mars, but because of the thinner atmosphere and lower gravity of the planet, sand grains, once in motion, can move faster and to a longer distance than on Earth. The sand flow rate, known as flux, of the Nili Patera dunes is approximately equal to the flux of the dunes in Victoria Valley, Antarctica. The Nili Patera dune movement can be used to predict rock erosion rates due to sand blasting the rocks. Based on the gathered evidence, rock erosion rates are predicted to be close to the ones in Antarctica. In a paper published in the journal Nature, NASA scientists report that they have detected motion of Nili Patera dunes up to a height of as "coherent units across the Martian landscape". These discoveries have led to increased understanding of the role the wind plays in erosion phenomena of the Martian landscape. This, in turn, can lead to better planning of future Mars expeditions, both human and robotic. ==Images by HiRISE==
Images by HiRISE
File:Dark sand dunes on Nili Patera.jpeg |Dark sand dunes on Nili Patera of probable volcanic origin. The lighter-coloured surface is ancient lava, which has cooled. The cracks on the lava floor are filled with dark, volcanic sand. File:Dunes and Ripples in Nili Patera.jpg|Dunes in Nili Patera, showing wind-created ripples and an avalanche on the lee side of the centre dune File:Barchan dunes at Nili Patera.jpg |Barchan dunes at Nili Patera File:Nili Patera Dune Field anaglyph.jpg|Nili Patera dune field anaglyph 3D ESP 022364 1890 Active Sand in Nili Patera.jpg == See also ==
Source: Wikipedia ↗
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