December 13, 2012
New Image Shows Mini Nile River On Titan
Lee Rannals for redOrbit.com - Your Universe Online
The find is the first time images have revealed a tier system this vast, and in such high resolution at any place other than Earth.
Scientists believe the river is filled with liquid because it appears dark along its entire extend in the images.
“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 this same Titan sea,” said Jani Radebaugh, a Cassini radar team associate at Brigham Young University.
“Such faults — fractures in Titan´s bedrock — may not imply plate tectonics, like on Earth, but still lead to the opening of basins and perhaps to the formation of the giant seas themselves.”
Titan is the only place scientists know that has stable liquid on its surface. The moon's hydraulic cycle involves hydrocarbons like thane and methane, similar to how Earth's cycle relies on water.
"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," said Steve Wall, the radar deputy team lead, based at NASA's Jet Propulsion Laboratory.
Cassini's visual and infrared mapping spectrometer confirmed liquid ethane at a lake in Titan's southern hemisphere in 2008.
“This radar-imaged river by Cassini provides another fantastic snapshot of a world in motion, which was first hinted at from the images of channels and gullies seen by ESA´s Huygens probe as it descended to the moon´s surface in 2005,” said Nicolas Altobelli, ESA´s Cassini Project Scientist.
Titan's north polar region, where the river valley flows into the sea Kraken Mare, is about the size between the Caspian Sea and the Mediterranean Sea. The real Nile River stretches about 4,100 miles, while the mini Nile on Titan goes for about 200 miles.
Image 2 (below): 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. Image Credit: NASA/JPL-Caltech/ASI