Saturn

Saturn’s Icy Rings

Saturn is the second largest planet, next to Jupiter, and the two “gas giants” have interesting similarities and differences.

Scientists theorize that Saturn has a terrestrial core surrounded by a layer of metallic hydrogen that gradually turns gaseous in the planet’s upper atmosphere. Wind speeds within parallel “belts” of storms on Saturn are three times faster than on Jupiter, though they don’t appear to be as volatile. Like Jupiter, the atmosphere rotates quickly on it’s axis and at different speeds at the poles than near the equator.

Saturn was first explored in the 1980’s when Pioneer 11 and Voyager 1 and 2 returned images of the icy comets and frozen moons balanced within the gravitational field of this massive planet.

The bright rings of Saturn make the planet the most recognizable in the solar system. They revolve at high speeds around Saturn’s equator, expanding 200,000 kilometers in width yet only 90 meters in height. NASA scientists discovered that the particles within Saturn’s rings are mostly space dust, rock, and ice; the remnants of a large comet or possibly a small moon that disintegrated and became locked into a stable orbit around the planet, much the way the moon revolves around the earth.

When the Cassini orbiter arrived in 2004, scientists could discern that the rings are actually divided into narrower bands with gaps in between, each consisting of material grouped together by size and density. The icy rings reflect sunlight and are more luminous than Saturn itself.

The Cassini-Huygens mission was a joint endeavor of NASA, the ESA, and the ASI that began in 1997. The Huygens lander safely touched down on Saturn’s largest moon, Titan, in 2005, providing scientists with valuable information about the habitability of the distant solar system. After 20 years, the mission was completed on September 15, 2017, and the Cassini orbiter was placed on a pathway of destruction and continued to transmit images before breaking apart in Saturn’s hostile atmosphere.

Saturn’s Largest Moon, Titan

When Titan was explored by the Huygens lander in 2005, the spacecraft discovered a hazy atmosphere containing 98% nitrogen with trace amounts of hydrogen and methane. Hydrocarbon lakes in the northern and southern hemispheres could be contributing to a weather system similar to earth’s, with methane “rains” that storm down into lakes and rivers, shaping the geology of Titan.