Cassini Finds Flooded Canyons on Titan

NASA | AUGUST 14, 2016

NASA's Cassini spacecraft has found deep, steep-sided canyons on Saturn's moon Titan that are flooded with liquid hydrocarbons. The finding represents the first direct evidence of the presence of liquid-filled channels on Titan, as well as the first observation of canyons hundreds of meters deep.

NASA's Cassini spacecraft pinged the surface of Titan with microwaves, finding that some channels are deep, steep-sided canyons filled with liquid hydrocarbons. One such feature is Vid Flumina, the branching network of narrow lines in the upper-left quadrant of the image. Credit: NASA/JPL-Caltech/ASI

The Cassini observations reveal that the channels -- in particular, a network of them named Vid Flumina -- are narrow canyons, generally less than half a mile (a bit less than a kilometer) wide, with slopes steeper than 40 degrees. The canyons also are quite deep -- those measured are 790 to 1,870 feet (240 to 570 meters) from top to bottom.

The branching channels appear dark in radar images, much like Titan's methane-rich seas. This suggested to scientists that the channels might also be filled with liquid, but a direct detection had not been made until now. Previously it wasn't clear if the dark material was liquid or merely saturated sediment -- which at Titan's frigid temperatures would be made of ice, not rock.

Key to understanding the nature of the channels was the way Cassini's radar signal reflected off the bottoms of the features. The radar instrument observed a glint, indicating an extremely smooth surface like that observed from Titan's hydrocarbon seas. The timing of the radar echoes, as they bounced off the canyons' edges and floors, provided a direct measure of their depths.

The presence of such deep cuts in the landscape indicates that whatever process created them was active for a long time or eroded down much faster than other areas on Titan's surface. The researchers' proposed scenarios include uplift of the terrain and changes in sea level, or perhaps both.

While the altimeter data also showed that the liquid in some of the canyons around Ligeia Mare is at sea level -- the same altitude as the liquid in the sea itself -- in others it sits tens to hundreds of feet (tens of meters) higher in elevation. The researchers interpret the latter to be tributaries that drain into the main channels below.

YOU MAY ALSO LIKE

NASA Finds Possible Second Impact Crater Under Greenland Ice

A NASA glaciologist has discovered a possible second impact crater buried under more than a mile of ice in northwest Greenland.

Mars Rover's Weather Data Bolster Case for Brine

Martian weather and soil conditions that NASA's Curiosity rover has measured, together with a type of salt found in Martian soil, could put liquid brine in the soil at night.

Mysterious Blast Studied with NASA Telescopes

A brief and unusual flash spotted in the night sky on June 16, 2018, puzzled astronomers and astrophysicists across the globe.

Hubble Observes One-of-a-Kind Star Nicknamed 'Nasty'

Astronomers using NASA's Hubble Space Telescope have uncovered surprising new clues about a hefty, rapidly aging star whose behavior has never been seen before in our Milky Way galaxy.

Mystery orbits in outermost reaches of solar system not caused by ‘Planet Nine’

The strange orbits of some objects in the farthest reaches of our solar system, hypothesised by some astronomers to be shaped by an unknown ninth planet, can instead be explained by the combined gravitational force of small objects orbiting the Sun beyond Neptune.

Confirmation of Toasty TESS Planet Leads to Surprising Find of Promising World

A piping hot planet discovered by NASA’s Transiting Exoplanet Survey Satellite (TESS) has pointed the way to additional worlds orbiting the same star, one of which is located in the star’s habitable zone. If made of rock, this planet may be around twice Earth’s size.