The paper, "Multiple origins of linear dunes on Earth and Titan," examines a possible new mechanism for the development of very large linear dunes formed on the surface of Titan, Saturn's largest moon.
The authors examined the linear – or longitudinal – dunes that stretch across the surface of China's Qaidam Basin, finding them composed of sand and some salt and silt. The latter two elements make the dunes cohesive or sticky.
According to the study, this leads to a complete change in dune form from transverse dunes to linear dunes, even though the wind speed and direction does not change. Typically transverse dunes are formed by winds from a narrow directional range while longitudinal or linear dunes are formed by winds from two obliquely opposing directions. These findings offer an alternative interpretation of similar dunes found on Titan.
Hesp and Rubin suggest that if the giant linear dunes found on the surface of Titan are also formed from cohesive sediment, then they too could be formed by single-direction winds. This is in sharp contrast to earlier studies, which assumed that the sediments were loose and interpreted the dune shape as evidence of winds coming from alternating directions. The alternative hypothesis that Titan's linear dunes are formed in cohesive sediment has significant implications for studies on Titan; if the Hesp and Rubin alternative is correct, new hypotheses regarding the composition, origin, evolution, grain size, stickiness, quantity, global transport patterns and suitability for wind transport of Titan's sediment; the velocities, directions and seasonal patterns of Titan's winds; and overall surface wetness will all have to be completely reassessed.For more information, contact Patrick Hesp at 225-205-6317 or firstname.lastname@example.org.
Ashley Berthelot | EurekAlert!
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University of Maryland researchers contribute to historic detection of gravitational waves and light created by event
On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...
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Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....
Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).
When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...
Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.
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Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.
It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...
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