Cassini mission scientists think the appearance of a cloud of dicyanoacetylene ice in Titan’s stratosphere is explained by ‘solid-state’ chemistry taking place inside ice particles.
The cloud is located in Titan’s stratosphere and is made of a compound known as dicyanoacetylene (C4N2), an ingredient in the chemical cocktail that colors the moon’s brownish-orange atmosphere.
Decades ago, NASA’s Voyager 1 spacecraft spotted an ice cloud just like this one. What has puzzled scientists ever since is this: they detected less than 1% of the dicyanoacetylene gas needed for the cloud to condense.
Recent observations from NASA’s Cassini mission yielded a similar result. Using the Cassini Composite Infrared Spectrometer (CIRS), the scientists found a large high-altitude cloud made of the same frozen chemical.
Yet, just as Voyager found, when it comes to the vapor form of this chemical, CIRS reported that Titan’s stratosphere is as dry as a desert.
“The appearance of this ice cloud goes against everything we know about the way clouds form on Titan,” said CIRS co-investigator Dr. Carrie Anderson, from NASA’s Goddard Space Flight Center.
Source: NASA researchers propose exotic ice cloud in Titan’s stratosphere formed by ‘solid-state’ chemical reactions