Giant sand dunes make up the surface of Titan, Saturn’s moon, and these dunes made of hydrocarbon particles may have existed for thousands of years. Radar images of the dunes by NASA’s Cassini spacecraft suggest that orbital variations of Saturn affect the shape of the dunes, which in turn reflect the resulting changes in weather patterns. According to Ryan Ewing, a geologist at Texas A&M University in College Station, who led the study, it may take as long as 3,000 Saturn years (or 90,000 Earth years) for a single dune to change direction. His team noticed ‘star’ shaped dunes that might have formed due to prevailing winds blowing from several directions. Interestingly, the smaller star-shaped dunes are oriented in a different direction from the larger, linear ones. The team calculated that it would have taken several thousand years for the winds to change direction and start forming the star-shaped dunes. Ewing now plans to study the effect of shifting orbital patterns of Saturn on Titan’s winds.
Read more in Nature.
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