Image of the Day --NASA Finds Vast River System on Saturn's Moon Titan

 

 

        

 

Titan has been considered a “unique world in the solar system” since 1908 when, the Spanish astronomer, José Comas y Solá, discovered that it had an atmosphere, something non-existent on other moons. It seems perfectly appropriate that one of the prime candidates for life in our solar system, Saturn's largest moon, should have surface lakes, lightning, shorelines, relatively thick nitrogen atmosphere, seasons, and now, a vast river system.

Scientists with NASA's Cassini mission have spotted what appears to be a miniature, extraterrestrial likeness of Earth's Nile River: a river valley on Saturn's moon Titan that stretches more than 200 miles (400 kilometers) from its "headwaters" to a large sea. It is the first time images have revealed a river system this vast and in such high resolution anywhere other than Earth. Scientists deduce that the river, which is in Titan's north polar region, is filled with liquid hydrocarbons because it appears dark along its entire length in the high-resolution radar image, indicating a smooth surface.

"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, Provo, Utah. "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 other world we know of that has stable liquid on its surface. While Earth's hydrologic cycle relies on water, Titan's equivalent cycle involves hydrocarbons such as ethane and methane. In Titan's equatorial regions, images from Cassini's visible-light cameras in late 2010 revealed regions that darkened due to recent rainfall. Cassini's visual and infrared mapping spectrometer confirmed liquid ethane at a lake in Titan's southern hemisphere known as Ontario Lacus in 2008.

"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 radar image here was taken on Sept. 26, 2012. It shows Titan's north polar region, where the river valley flows into the sea called Ligeia Mare, a sea that is, in terms of size, between the Caspian Sea and the Mediterranean Sea on Earth. The real Nile River stretches about 4,100 miles (6,700 kilometers). The processes that led to the formation of Earth's Nile are complex, but involve faulting in some regions.

 

                                    

 mage credit: NASA/JPL-Caltech/ASI

Comments

[Knize10]

Its too cold for any life except imaginary creatures in scientists imagination and they do have a very florid minds.

[Delvan]

The suggested possibilities for life on Titan are not on the surface, but below the surface where temperatures would be warmer. We have life on our planet that survives hydrothermal vents and life at sub zero temperatures.

Life in a liquid methane solvent would likely take advantage of lipoproteins and proteolipids since it isn't (like life on Earth) submerged in a polar solvent.

[pAYNER]

I heard its warm at the core do to the planets rotation around. I am not a science Nerd, but i think its more then Possible that the planet can produce and sustain life. Saturn's Moon Titan, best chance for life in our universe and its right next door lol

[Greg]

Water is our life blood, and the life blood of many (if not all) life on our planet. It is only natural that we would assume life is only possible at temperatures where there could be liquid water.

What if there is life on Titan, but liquid methane is its life blood. The temperatures on Titan could be warm and balmy to them, but a planet where water is liquid would be to them as a planet where rock is liquid is to us.

[mulvey]

It is awfully pig headed of us to assume that life can 0NLY emerge with liquid water being present. There are extremofiles on earth that survive in hydrothermal vents that are poisonous to us, and also in frozen lakes in antarctica that are much too cold to sustain human life. IT would seem that rivers, lakes, oceans, tectonic plates, water (methane) cycles are the inevitable results of gravity. If anything, this reassures me that there is life elsewhere in the universe, no matter how strange it may be,