Saturn in repose

Image courtesy of NASA/JPL-Caltech/Space Science Institute

Saturn in Repose
| published August 28, 2015 |

By Thursday Review staff

The planet Saturn takes on a moody, surreal appearance in this image captured using infrared filters on a camera aboard the Cassini spacecraft—a photograph taken from the dark side of the rings about one degree from the ring plane.

The use of the filter was not for creative effect, but was used so that scientists on Earth can more accurately study the density and the movements of clouds in Saturn’s complex, thick atmosphere—especially the quantities of methane present in the clouds. The filter is sensitive to the infrared wavelengths absorbed by methane. Saturn’s atmosphere is a dense soup of helium, hydrogen, ammonia, methane, and other gases, along with dust.

According to NASA, “the darker areas reveal clouds that are lower in the atmosphere, therefore under more methane.” Higher altitude clouds can be seen in the lighter regions of the cloud cover. The dark band near the bottom is a shadow of the rings.

The thick, soup-like appearance of the atmosphere does not indicate calm. In fact, Saturn’s winds can reach—or exceed—1000 miles per hour, and large parts of the planet’s surface area is beset by storms. This photo was taken from a distance of about 930,000 miles above the surface of Saturn.

Related Thursday Review articles:

Saturn’s Outward Calm; Thursday Review staff; Thursday Review; May 18, 2015.

A Close-Up Look at Distant Pluto; Keith H. Roberts; Thursday Review; July 14, 2015.