While Saturn’s largest moon Titan remains a source of constant mystery for astronomers, one its enduring enigmas might have just been solved by NASA. The space agency has been conducting research on the “magic islands” spotted by the Cassini spacecraft in 2013. On one of its 2013 flybys, Cassini’s radar instruments detected in one of Titan’s lakes what appeared to be a set of islands. The “islands” did not appear in previous images and disappeared just a few days later, leaving astronomers scratching their heads in wonder.
Luckily, researchers at NASA's Jet Propulsion Laboratory weren’t content with letting that mystery stand and set to work on an experiment to determine what could have caused such disappearing "islands." The experiment involved recreating the chemical and physical conditions of Titan’s lakes and then subjecting that solution to the same temperature and chemical changes that occur during rainfall. When ethane-rich solutions similar to Titan’s rainfall were added to the simulated Titan lake fluid, the process of exsolution occurred, causing nitrogen to boil violently out of the solution.
Heavy rainfall on Titan could release large amounts of ethane into Titan’s seas, which could then cause nitrogen to boil out. According to Cassini radar investigator Jason Hofgartner, the resulting nitrogen bubbles could form giant fields of dense nitrogen foam which might explain the “magic” islands:
Thanks to this work on nitrogen's solubility, we're now confident that bubbles could indeed form in the seas, and in fact may be more abundant than we'd expected.
“Foam on one of Saturn’s moon’s seas? Who cares,” you might find yourself asking. Well, besides being interesting, this research is important for any future exploration of Titan which is looking more and more like a possibility. Foam in Titan’s seas could really jam up the propellers and sensors on those deep-sea space submarines NASA is working on. We can’t have that happening, can we?
Of all the objects in our solar system, Titan is most similar to Earth in terms of atmospheric composition. Titan has a dense gaseous atmosphere complete with rainfall which forms rivers and lakes of methane on Titan’s −290 °F (−179 °C) surface. However cold and inhospitable that might sound, a Cornell University study last year speculated that Titan could be home to primitive life forms due to its abundance of hydrogen cyanide, a compound believed to be one of the chemical building blocks of primordial life.