A River Runs Through It

Canyons on Titan
Canyons on Titan

…or has very recently, geologically speaking.

But that river would be of liquid methane, not water. And it would be hundreds of degrees below zero. And it would be on Saturn’s moon Titan.

This topographic radar image, taken by Cassini during a flyby of the moon on May 21, pierced the dense clouds of Titan to reveal rough, broken terrain (the bright areas) surrounding channels filled with fine sediments (the dark regions), apparently washed down by rains and erosion from the high plateaus on the right side of the image. In addition, the area looks to have been thoroughly carved by a river channel, seen on the lower left side. Whether liquid methane still flows in these channels remains to be discovered.

Titan in natural color
Titan in natural color

This is not a photographic image per se, but rather the interpretation of radar data that shows surface features based on their relative reflectivity of the radar signal. Finer sediments absorb the signal more, so they appear dark, while bright areas are highly radar-reflective and appear white….most likely cliffs and exposed bedrock.

The haze-enshrouded Titan is still full of mysteries, but the recent flybys by Cassini have revealed a world full of dynamic geology and weather processes beneath the clouds where methane rains fill rivers and lakes and water ice oozes from freezing volcanoes and hardens into rock. And with more flybys scheduled over the next few months there’ll be many more discoveries to come.

View the official release here.

Image: NASA/JPL