NASA’s Cassini probe has found a strange ice cloud over Titan that appears to be made up of compounds that barely exist in the atmosphere of Saturn’s largest moon.
Located in Titan’s stratosphere, the cloud is made of a compound of carbon and nitrogen known as dicyanoacetylene, an ingredient in the chemical cocktail that colours the giant moon’s hazy, brownish-orange atmosphere.
And it is not the first time NASA scientists spotted the mysterious cloud.
Decades ago, the infrared instrument on NASA’s Voyager 1 spacecraft spotted an ice cloud just like this one on Titan.
Using Cassini’s composite infrared spectrometer, or CIRS — researchers found a large, high-altitude cloud made of the same frozen chemical.
Although Earth’s stratosphere has scant moisture, wispy nacreous clouds (also called polar stratospheric clouds) can form under the right conditions.