From the JPLnews press release
“Titan is the only place we’ve found besides Earth that has a liquid in continuous movement on its surface,” said Steve Wall, the radar deputy team lead, based at NASA’s Jet Propulsion Laboratory, Pasadena, Calif. “This picture gives us a snapshot of a world in motion. Rain falls, and rivers move that rain to lakes and seas, where evaporation starts the cycle all over again. On Earth, the liquid is water; on Titan, it’s methane; but on both it affects most everything that happens.”
The original image is available here
This image from NASA’s Cassini spacecraft shows a vast river system on Saturn’s moon Titan. It is the first time images from space have revealed a river system so vast and in such high resolution anywhere other than Earth.
The image was acquired on Sept. 26, 2012, on Cassini’s 87th close flyby of Titan. The river valley crosses Titan’s north polar region and runs into Ligeia Mare, one of the three great seas in the high northern latitudes of Saturn’s moon Titan. It stretches more than 200 miles (400 kilometers).
Scientists deduce that the river is filled with liquid because it appears dark along its entire extent in the high-resolution radar image, indicating a smooth surface. That liquid is presumably ethane mixed with methane, the former having been positively identified in 2008 by Cassini’s visual and infrared mapping spectrometer at the lake known as Ontario Lacus in Titan’s southern hemisphere. Though there are some short, local meanders, the relative straightness of the river valley suggests it follows the trace of at least one fault, similar to other large rivers running into the southern margin of Ligeia Mare (see PIA10008). Such faults may lead to the opening of basins and perhaps to the formation of the giant seas themselves.
Don’t forget the Geminid meteor shower tonight! There’s a new moon so it should be a good show. Provided the sky is clear…
Adds If, like me, you’re looking at an overcast sky tonight, you might want to check out Nasa’s live on-line feed from a skyward pointing camera at NASA’s Marshall Space Flight Center in Huntsville, Ala. There’s a Nasa chat on the Gemind meteor shower planned for tonight too. I’ll embed the live Ustream feed when it’s available.
Update Here’s the Ustream live-feed.