River Networks on Titan Reshape Saturn's Largest Moon's Surface

River networks on Titan are shaping the surface of Saturn's largest moon, according to a new study.

Researchers from the Massachusetts Institute of Technology (MIT) and the University of Tennessee at Knoxville have analyzed the images of the river networks of Titan and found that some regions of Saturn's largest moon are getting shaped by the flowing rivers.

"It's a surface that should have eroded much more than what we're seeing, if the river networks have been active for a long time," said Taylor Perron, the Cecil and Ida Green Assistant Professor of Geology at MIT, in a news release.

"It raises some very interesting questions about what has been happening on Titan in the last billion years." 

The thick clouds of methane and nitrogen-rich atmosphere prevented a closer look at Titan thus far. However, new images coming from the Cassini-Huygens spacecraft are throwing more light on the river patterns.

Based on analysis of these pictures, it appears that there has been very little erosion of the moon's surface. This could mean either that the erosion is very slow or a recent phenomenon has wiped out the older river systems.

The surface of the moon is surprisingly similar to that of the earth's surface with so few craters on it. What could be the reason for such a low crater count? Many phenomena including volcanoes, glaciers and river networks have all reshaped the Earth's surface over billions of years. Similar forces seem to be at work on Titan's surface. But identifying these is a challenge.

The researchers studied the images of Titan taken by NASA's Cassini-Huygens spacecraft and mapped 52 river networks. They compared the images with the model of the evolution of rivers developed by Perron to find how the evolution of river has changed. The researchers found that the river networks on Titan resembled the ones on Earth, suggesting that the geological process which appears due to natural forces may have caused the moon's icy shape to change.  

With similar Earth-like surface features, the findings from Titan may help researchers in understanding how rivers form and how they could have shaped a planet like Earth over millions of years.

"It's a weirdly Earth-like place, even with this exotic combination of materials and temperatures," Perron said. "And so you can still say something definitive about the erosion. It's the same physics."

The findings will be published in the Journal of Geophysical Research-Planets.