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Published on January 17th, 2013 | by Joshua S Hill

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Titan Is Perpetually Being Swept Clean By Dunes

January 17th, 2013 by

Using observations from NASA’s Cassini spacecraft in orbit around Saturn, researchers from NASA’s Goddard Space Flight Center have discovered that Titan — Saturn’s largest moon — has dunes of hydrocarbon sand which are slowly but steadily filling the impact craters left on the moon’s surface, giving it a deceptively younger appearance than its brothers and sisters in orbit.

Titan's Surface Changing with Shifting Sands

This image taken with the Cassini radar instrument shows two craters on Titan: the crater Sinlap (left), which is a relatively ‘fresh’ crater, with a depth-to-diameter ratio close to what we see on Ganymede, and Soi (right), an extremely degraded crater, with a very small depth compared to similar craters on Ganymede. These craters are both about 80 km (almost 50 miles) in diameter. The Sinlap image was taken on Feb. 15, 2005. The Soi image is a mosaic of two images from May 21, 2009 and July 22, 2006.
Image Source: Catherine Neish/NASA/JPL-Caltech/ASI/GSFC

“Most of the Saturnian satellites – Titan’s siblings – have thousands and thousands of craters on their surface. So far on Titan, of the 50 percent of the surface that we’ve seen in high resolution, we’ve only found about 60 craters,” said Catherine Neish, a Cassini radar team associate based at NASA’s Goddard Space Flight Center, Greenbelt, Md.

“It’s possible that there are many more craters on Titan, but they are not visible from space because they are so eroded. We typically estimate the age of a planet’s surface by counting the number of craters on it (more craters means an older surface). But if processes like stream erosion or drifting sand dunes are filling them in, it’s possible that the surface is much older that it appears.”

“This research is the first quantitative estimate of how much the weather on Titan has modified its surface,” adds Neish.

The discovery was made when Neish and her team started comparing craters on Titan to craters on Jupiter’s moon Ganymede, a giant moon with a water ice crust similar to Titan. The two moons should have been somewhat similar, but there were discrepancies.

“We found that craters on Titan were on average hundreds of yards (meters) shallower than similarly sized craters on Ganymede, suggesting that some process on Titan is filling its craters,” says Neish, who is lead author of the paper published in the journal Icarus. 

There are several theories at hand that could explain the craters’ various depths, but the NASA team believe that windblown sand is the most likely option.

The full report can be viewed at NASA’s website

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About the Author

I'm a Christian, a nerd, a geek, a liberal left-winger, and believe that we're pretty quickly directing planet-Earth into hell in a handbasket! I work as Associate Editor for the Important Media Network and write for CleanTechnica and Planetsave. I also write for Fantasy Book Review (.co.uk), Amazing Stories, the Stabley Times and Medium.   I love words with a passion, both creating them and reading them.



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