NASA and Saturn: New Ice Cloud on Titan

While many people in the Northern Hemisphere felt that winter took forever to go away last year, it turns out that we have nothing on Saturn's moon Titan, which has seasons that last 7 ½ years by the Earth calendar. NASA's Cassini spacecraft has been observing winter on Titan and recently learned more about the unique fierceness of that season there, according to a release.

The researchers noticed, for instance, that currently there is a large new cloud that gathers frozen compounds in the lower to middle part of the moon's stratosphere, which is a stable area above the moon's active weather layer, or troposphere.

This information arrives in addition to what scientists knew in 2012, when they spotted a large cloud about 186 miles above Titan's south pole. The new ice cloud is in the same area but is at an altitude of 124 miles.

Cassini's infrared instrument detected the new cloud. That instrument is called the Composite Infrared Spectrometer (CIRS), and it finds profiles of atmosphere at thermal wavelengths that are invisible to us.

The new cloud is similar to fog on Earth but is flat on top, according to the release.
Cassini has seen parts of the movement from fall to winter at the south pole of Titan for the last few years. This has been the first time that a spacecraft has seen Titan's winter begin. Also, because the winter lasts so long, the south pole will still have winter at the end of the Cassini mission in 2017, confirmed the release.

"When we looked at the infrared data, this ice cloud stood out like nothing we've ever seen before," Carrie Anderson, NASA's Goddard Space Flight Center, said in the release. "It practically smacked us in the face."

Anderson recently presented the conclusions at the annual Meeting of the Division of Planetary Sciences of the American Astronomical Society, in Maryland, the release said.

For more great nature science stories and general news, please visit our sister site, Headlines and Global News (HNGN).

Follow Catherine on Twitter @TreesWhales