Thanks to NASA's Cassini spacecraft, whose mission it was to collect data about Saturn's most fascinating moon, researchers have learned everything they could possibly think of about the surface of Titan. Or so they thought. But in a new study published this week in the journal Nature, astronomers and planetary meteorologists are reconsidering exactly what their expectations were for the distant satellite.
Two years ago, a viscous cloud was seen over Titan's south pole, and planetary scientists mistakenly made the assumption that the anomaly was ordinary gases floating 300 km above Titan's surface. However, a new study reveals that the cloud is actually composed of hydrogen cyanide ice, and it's leading researchers to think that the pole is much colder than they once thought.
"This is telling us that you have to expect the unexpected, even on 'planets' that we thought we knew relatively well" lead researchers of the study published in Nature, Remco de Kok of the Leiden University of the Netherlands says.
Exposing potential flaws in models and weather patterns we've come to recognize in research of planetary histories, of every planet in our solar system including Earth, the research team led by de Kok discovered that expectations often don't fit reality when it comes to the cosmic study. Utilizing the infrared spectrometer on NASA's Cassini mission, de Kok found that the cloud through and through was highly composed of hydrogen cyanide, one of many hydrocarbons circulating through Titan's atmosphere. But the fact that cloud rose to heights 210 km higher than expected and showed signs of cyanide ice led the researcher to question how cold the south pole really is and how the shift had quickly changed.
Though the cloud was originally spotted in May 2012, Cassini regularly has measured the cloud's temperature and has consistently found it too warm for ice to form. But only three months after Cassini's latest measurement, de Kok's research proved an abundance of hydrogen cyanide ice and that means the temperatures have dropped more than 100 degrees Celsius in a relatively short period of time.
As de Kok points out that Titan's south pole seems to be losing heat to outerspace much faster than it can regenerate heat from air masses sinking below within its very own atmosphere, other researchers like Sarah Horst from Johns Hopkins University are looking to revise their global-circulation models of Titan's atmosphere already.
"We are transitioning to this very exciting time where we are able, for the first time, to think about Titan as a dynamic system" Horst says. "This is really cool."
