Cassini Gathers New Clues Regarding Titan as the Seasons Shift

New images of the methane and ethane seas and lakes located near Titan's north pole offer new insights into how they formed and the Saturnian satellite's Earth-like "hydrologic" cycle, which is comprised of hydrocarbons rather than water.

Researchers previously relied on radar to penetrate Titan's opaque clouds and haze. However, a series of fortunate events, including the dissipation of a thick cap of haze as summer approaches in the moon's north, recently offered the probe Cassini nearly cloudless, rain-free looks at Titan's surface.

The result are a mosaic of images in infrared light colored in by visual and infrared mapping spectrometer, which maps infrared colors onto the visible-color spectrum. Based on the data, scientists believe parts of Titan's lakes and seas may have evaporated, leaving behind the equivalent of Earth's salt flats.

"The view from Cassini's visual and infrared mapping spectrometer gives us a holistic view of an area that we'd only seen in bits and pieces before and at a lower resolution," Jason Barnes, a participating scientist for the instrument at the University of Idaho, said in a statement. "It turns out that Titan's north pole is even more interesting than we thought, with a complex interplay of liquids in lakes and seas and deposits left from the evaporation of past lakes and seas."

The new images also unveil a bright spot previously undetected. Though it's not entirely clear what this spot is, scientists nevertheless hypothesize that it may be the key as to why nearly all of the moon's lakes are found in this region.

"Ever since the lakes and seas were discovered, we've been wondering why they're concentrated at high northern latitudes," said Elizabeth Turtle, a Cassini imaging team associate based at the Johns Hopkins Applied Physics Laboratory. "So, seeing that there's something special about the surface in this region is a big clue to help narrow down the possible explanations."

A full Saturn year is 30 years, of which Cassini has observed nearly a third.

"Titan's northern lakes region is one of the most Earth-like and intriguing in the solar system," said Linda Spilker, Cassini project scientist, based at NASA's Jet Propulsion Laboratory, Pasadena, Calif. "We know lakes here change with the seasons, and Cassini's long mission at Saturn gives us the opportunity to watch the seasons change at Titan, too. Now that the sun is shining in the north and we have these wonderful views, we can begin to compare the different data sets and tease out what Titan's lakes are doing near the north pole."