NASA Captures Winter on Titan
Newly acquired images from NASA's Cassini aircraft have shown that winter on Saturn's moon of Titan is defined by staggeringly large winter storms.
The storms seem to originate around Titan's South Pole and although this is not the first major storm filmed on Titan, it is far and away the largest and most dramatic, NASA said in a press release. The storms were first seen by NASA spacecraft in 2012.
The Cassini spacecraft which captured these newest images has been catching bits and pieces of Titan's movement from fall to winter, each of which lasts for seven and one half years. It will still be winter when the Cassini mission ends in 2017.
Cassini was able to witness the winter storms thanks to its Composite Infrared Spectrometer, which found the storm was relatively low in density, like fog on Earth. The CIRS works by taking profile pictures of the atmosphere with invisible thermal wavelengths.
"When we looked at the infrared data, this ice cloud stood out like nothing we've ever seen before," said Carrie Anderson of NASA's Goddard Space Flight Center in Greenbelt, Maryland. "It practically smacked us in the face."
One reason the storms were so fascinating is that they form in a different manner than storms here on Earth.
Storms on Earth form when water evaporates from the Earth's surface meets cooler temperatures in the atmosphere. Once the air pressure and temperature reach the proper conditions, the water vapor condenses back into water and falls to Earth.
On Titan, gases in the warmer hemisphere travel to the colder one, sinking along the way. As the gases warm gases move, they cool off and sink, forming yet more layers of clouds and by extension massive storms.