Scientists Think They’ve Spotted Waves In Titan’s Oceans
If you watched Sunday’s episode of Cosmos, you know that Tyson and the Spaceship of the Imagination headed to Titan, Saturn’s gigantic moon that is thought to be one of the most likely spots for life beyond planet Earth in our solar system. As the ship cruised around, Tyson explained that the hydrocarbon lakes of Titan are the only bodies of surface liquid found outside of Earth. Just one day after that episode aired, scientists announced that they may have caught a glimpse of moving waves on the seas of Titan.
Of course, the hero in all this is the Cassini spacecraft, which continues to provide breathtaking and historical images of the solar system’s most picturesque planet. In 2012 and 2013, the spacecraft caught some reflective sunlight off the surface of a sea called Punga Mare, and scientists think it may have come from ripples — the kind only made on liquid. These aren’t big waves, we’re talking a few centimeters. But given that Punga Mare has always appeared to be completely flat, it’s still a major discovery.
A second report of possible waves came from a Cassini image from last summer of what looked like an island in the sea Ligeia Mare. Much like the mysterious Mars rock, 16 days after it appeared it was no longer visible. After ruling out the existence of an island, scientists concluded that the most likely explanation for the image is waves.
Titan has weather that resembles Earth’s, at least a little bit. It rains liquid there, though not water — we’re talking methane and ethane — and it evaporates from the moon’s surface in a cycle. Scientists have never known if the composition of the liquid hydrocarbons on Titan makes them denser than water, and harder to move around, and/or whether the winds are too weak.
More evidence of liquid on Titan may come in the next few years as Titan cycles from winter into spring. Springtime in the north of Titan, where the majority of lakes exist, brings high winds, and thus the opportunity to ripple more liquid. A planetary scientist from Johns Hopkins says that “Titan may be beginning to stir” and that “oceanography is no longer just an Earth science.” That’d be a pretty sweet study abroad to conduct field research, wouldn’t it?
NASA proposed dropping a probe into a lake on Titan, but that proposal never got off the ground (sorry). It’d be interesting, though — if the probe crashed into the surface, we might not learn enough, but if it actually splashed in, who knows? Cassini will end its mission in three years by diving into Saturn, but it’s unclear whether its trajectory will allow it a chance to catch some waves.