Date:16 March 2017
A new experiment has left NASA scientists confident that they’ve learned something new about the Saturn’s moon Titan. On its many lakes and seas there’s an occasional dramatic eruption of bubbles.
By David Grossman
The finding comes from researchers at NASA’s Jet Propulsion Laboratory in Pasadena, California, who simulated the surface conditions of Titan in a lab. The haze in Titan’s atmosphere, which is largely made up of nitrogen, gives it an anti-greenhouse effect by reflecting sunlight back into space, leaving the surface temperature at −179.2 °C. That haze is punctured by Titan’s various clouds, which scientists believe are made up of methane, ethane, or other simple organics.
The scientists found that “significant amounts of nitrogen can be dissolved in the extremely cold liquid methane that rains from the skies and collects in rivers, lakes, and seas.” At that point, even “slight changes in temperature, air pressure or composition can cause the nitrogen to rapidly separate out of solution, like the fizz that results when opening a bottle of carbonated soda.”
Of course, this happens on a much greater scale than a can of soda. Saturn’s largest moon Titan is 50 percent bigger than Earth’s moon and is larger than the planet Mercury. These bubbles are abundant throughout Titan’s oceans, to the extent that scientists think they could be creating temporary island-like features on the landscape. And once an island-sized bubble pops, it leaves quite an eruption.
“In effect, it’s as though the lakes of Titan breathe nitrogen,” said Michael Malaska of JPL who led the study. “As they cool, they can absorb more of the gas, ‘inhaling.’ And as they warm, the liquid’s capacity is reduced, so they ‘exhale.'”
We have the satellite Cassini to thank for this startling image. On its flybys of the moon it found out that the composition of Titan’s lakes and seas varies from location to location, which makes the nitrogen less stable. The spacecraft, which is set to crash into Saturn in September, has brought back a startling amount of information on Saturn’s moons, which an emphasis on Titan and another watery world, Enceladus.
Images credit: NASA/JPL-Caltech/SSI/Univ. Arizona/Univ. Idaho
This article was originally written for and published by Popular Mechanics USA.