Tectonics, Sinkholes May Have Shaped Titan's Landscape: Map Reveals Clues about the Origin of Seas and Lakes on Saturn's Largest Moon
Rosen, Meghan, Science News
For a frigid hunk of rock and ice more than a billion kilometers away, Titan acts a lot like Earth. It has lakes and seas that may have formed in ways similar to those that created Earth's bodies of water, according to an analysis of the newest map of Titan's surface.
Vast, elongated seas and smaller, roundish lakes filled with oily liquid speckle the moon's north pole. They could be the handiwork of tectonics and sinkholes, geophysicist Randolph Kirk of the U.S. Geological Survey in Flagstaff, Ariz., reported December 12.
"Earth has seas, and rivers, and rain, and tectonics, and volcanism and glaciers," Kirk said. "Titan's got the full list from Earth, except for life."
Scientists received their first up-close look at the big moon in 2004, when Cassini, a spacecraft orbiting Saturn, snapped radar images of Titan's surface. The spacecraft spotted some of the moon's lakes and seas in 2006, but until now scientists didn't have a full picture of Titan's north pole.
The latest mosaic is a patchwork of coarse- and fine-resolution images from Cassini's flybys. Filling in the northern landscape's details helped Kirk figure out the forces that may have shaped the moon's geography.
This summer, when Kirk first looked at the new images, he noticed that the large seas seemed to cluster together. "Wow, that's really weird," Kirk remembers thinking. "It looks like a rectangular area."
The coastlines of the seas run parallel to the edges of the rectangle. "When geologists see straight lines, they immediately jump to the idea of tectonics," Kirk said.
Tectonics, or fracturing of a planetary body's crust, carves its signature into a landscape with the same lines and angles seen around Titan's seas, he said. …