In this synthetic aperture radar image obtained by NASA's Cassini spacecraft, two generally similar features, upper center and lower right, appear to be low mountains with grooves running roughly in the up-down direction. A set of straight lines are also visible at lower left. (photo: NASA)

PASADENA, Calif., Jan. 25 (UPI) -- NASA's Cassini spacecraft has found yet another mystery to be solved -- hills with a wrinkly radial pattern discovered on Titan, Saturn's largest moon.

The grooved mounds, located in a northern hemisphere region known as Belet, are about 50 miles wide and about 200 feet high. NASA scientists said the shapes of the landscape features have not been seen on Titan before, although they bear similarity to spidery features known as coronae on Venus. A corona is a circular to elliptical feature thought to result from the flow of heat in a planet's interior.


"This star-shaped pattern of the hills indicates something significant happening, ..." said Steve Wall of NASA's Jet Propulsion Laboratory. "It might be caused by tectonic forces, such as the forces that pull the crust of a planet apart, or rainfall that leads to erosion, or an ice intrusion like a dike."

All such forces produce grooves on Earth's surface, but Wall said NASA scientists are not yet sure what is happening on Titan.