Titan May Be Headed Toward Wild Weather as its Seasons Begin to Change
Saturn’s moon Titan, long observed by the spacecraft Cassini, might be headed toward some wild weather during its spring and summer based on two new models produced by NASA scientists.
As the seasons change in Titan’s northern hemisphere, a process that takes seven years, waves could start to ripple across the moon’s hydrocarbon seas just as hurricanes begin to swirl over the same region.
The model that attempts to predict the pattern of waves comes as scientists, confused as to why they hadn’t observed any driven by wind on the moon’s sprawling hydrocarbon seas and lakes, improved upon previous models by simultaneously taking into account Titan’s gravity, the viscosity and surface tension of the liquid in the lakes and the air-to-liquid density ratio.
“We now know that the wind speeds predicted during the times Cassini has observed Titan have been below the threshold necessary to generate waves," Alex Hayes, a member of Cassini’s radar team, said in a press release. "What is exciting, however, is that the wind speeds predicted during northern spring and summer approach those necessary to generate wind waves in liquid ethane and/or methane. It may soon be possible to catch a wave in one of the solar system’s most exotic locations.”
The other model, which has to do with hurricanes, predicts that the warming of the northern hemisphere could bring on the storms also known as tropical cyclones, similar to those on Earth that gain their energy from the build-up of heat from seawater evaporation.
However, scientists are wary of promising anything yet.
"For these hurricanes to develop at Titan, there needs to be the right mix of hydrocarbons in these seas, and we still don't know their exact composition," Tetsuya Tokano, who led the creation of the model, said. "If we see hurricanes, that would be one good indicator that there is enough methane in these lakes to support this kind of activity. So far, scientists haven't yet been able to detect methane directly."
As Scott Edington, Cassini's deput proncet scientist at NASA's Jet Propulsion Laboratory said, “If you think being a weather forecaster on Earth is difficult, it can be even more challenging at Titan. We know there are weather processes similar to Earth’s at work on this strange world, but differences arise due to the presence of unfamiliar liquids like methane.”