The Planet Saturn
One of the most stunning sites in the Solar System, its bright rings command our attention and demand we stop to acknowledge its beauty. Planet Saturn, the gas giant, has the the most visibly eye-pleasing rings of all the giants, but there is much more to it than just a collection of particles rotating around its substantial gravitational field.
Scales Of The Gigantic
At 120,000 kilometres (75,000 miles) in diameter, planet Saturn may not be as large as Jupiter but the planet is massive in comparison to the Earth. Orbiting at a distance of just over ten astronomical units (the distance between the Sun and the Earth is one AU), it takes planet Saturn nearly 30 Earth years to complete one trip around the Sun.
Despite its year taking so long, one day lasts just over ten and a half hours. Therefore, one Saturn-year is an incredible 10,760 Saturn-days long.
A Layered Giant
The planet’s composition is not dissimilar to Jupiter. With many layers of different chemicals with a solid core in the centre. The outermost layer is composed of clouds, below this lies a hydrogen and helium atmosphere. This transitions from a gaseous to a liquid state under pressure farther in.
Beneath this gaseous/liquid layer, the pressure forces the liquid hydrogen to form liquid metallic hydrogen. The metallic hydrogen is mixed with hydrogen. It is metallic hydrogen which powers planet Saturn’s magnetic field.
Finally, at the heart of the planet is a compressed rock and ice core.
Although we may think of planet Saturn as being a perfect sphere, this is far from the truth. The planet has an enormous bulge of several thousand kilometres around its equator. This is due to the relationship between Saturn’s relatively weak gravitational field which allows its atmosphere to extend farther than other planet and its fast-paced rotation.
A Many Mooned World
Planet Saturn has the greatest number of satellites of all the planets in the Solar System. It also is orbited by the appropriately named Titan, a planet-sized moon that is the second-largest satellite orbiting any of the worlds. As of today, there are 53 moons that have been given names. Yellow Magpie will take a closer look at these moons over the course of the coming weeks. Some of these satellites are enormous and fully spherical while others are irregular and little more than a few kilometres across.
Planet Saturn: The Ring World
The most famous aspect of planet Saturn is undoubtedly its rings. From a distance of just over 6,000 kilometres (3,750 miles) all the way to over 120,000 kilometres (75,000 miles), Saturn’s rings are a colossal feature of the Solar System. Astronomers have grouped different areas of the rings, which vary in structure and composition.
The faint ring closest to the planet is known as the D Ring. This ring contains very fine particles. Next out is the C, or Crepe, Ring which is a five metre thick layer of larger particles which contain lumps of ice. The B ring is the brightest area of planet Saturn’s rings. This brightness is created by large particles of ice.
As you head out farther from the planet the particles in the rings get larger and denser. One of the most interesting visual aspects of the ring system is the Cassini Division, an area that was previously thought to be empty of particles but we now known contains many other rings.
Beyond Cassini resides the A Ring which contains large ice boulders which have been rendered smooth from constantly smashing into each other.
There are several other rings and divisions or gaps but the outermost ring of planet Saturn is known as the F Ring, this ring is very thin and, at only one or two hundred kilometres in width, is one of the smaller rings of the planet.
One of the great sights in our small part of the Milky Way Galaxy is the visually alluring auroras of planet Saturn. Created by the interaction between the Sun’s plasma bursts and the planet’s magnetic field, the auroras on Saturn are very much visible from the Earth with the aid of powerful telescopes.
Highly Recommended Reading
Check out Yellow Magpie’s Jupiter: The Local Gas Giant Of The Solar System for more insight into the largest planet in the Solar System.
You may also wish to take a gander at The Solar System And Beyond: A Guide To The Cosmos.
Cosmos is a highly recommended book. It contains large, full-page pictures of the asteroids and writing on the subject by the highly competent author, Giles Sparrow.
For people living in Ireland or the United Kingdom, you can access: Cosmos from here.
For those who live in Canada, you can obtain: Cosmos here.
For Germany: Cosmos.
For France: Cosmos.