Other than Earth, Titan is the only celestial object in the solar system capable of fostering stable liquids on the surface. But now, after years of searching, scientists may have detected waves rippling on its seas — which, if confirmed, would be the first discovery of its kind.
The methane, or hydrocarbon, on Titan is essentially liquified natural gas. Though in fluid state, these massive bodies of liquid were thought to be exceptionally calm, leading to the suggestion that no waves exist on the surface of this Saturnian moon.
But back in 2012 and 2013, NASA's Cassini spacecraft captured several glints of sunlight on the surface one of Titan's hydrocarbon seas, Punga Mare. Looking at the images, these unusually bright reflections occupied a space no more than four pixels. But according to planetary scientist Jason Barnes, those reflections are a good indication of tiny ripples measuring no more than three-quarters of an inch (2 cm) high. As Nature News reports, he presented these findings yesterday (March 17th) at the Lunar and Planetary Science Conference:
Calculations of the waves' height suggested they were a puny few centimetres high. "Don't make your surfing plane reservation for Titan just yet," Barnes told the conference.
Knowing how the waves form will help scientists to better understand the physical conditions in Titan's lakes and seas. A NASA mission proposal, which was beaten by a proposal to return to Mars, would have sent a probe to float in one of Titan's lakes. "If we drop a lake lander in there, is it going to splat instead of splash?" asks Barnes.
There is still a chance that Cassini is seeing reflections off a wet, solid surface, such as a mudflat, rather than actual waves. Future observations might spot the waves of Punga Mare again, but Barnes says that there is no guarantee that Cassini will pass by in the right position before the end of its mission, a planned plunge into Saturn in 2017.
[Via Nature News]
Image: Ron Miller