Why Does Saturn Have Rings?
Saturn is a peculiar and one among the most beautiful of the planets in our solar system. The reason why many regards Saturn a sight of beauty comes from the ring that surrounds it.
Saturn was used as the official icon of the Discover Magazine for a number of years, and the glittering rings never failed to pique the curiosity of anyone who has laid their eyes on it.
Even though some of the other planets in our solar system like Uranus and Neptune have rings around them, they are too feeble to be picked up easily, and not as majestic as Saturn.
That is not the case with the Rings of Saturn as the main ring spans 300,000 kilometers in width and have a thickness of about 10 meters. Some areas of the rings also have a thickness of 1 kilometer.
The rings stay proud and visible around the planet, giving it a unique look that no other planet possess.
But what led to the formation of these rings?
Ring or Rings: what is the right word?
Saturn doesn’t have a ring, but many. So many that if we were to count the individual rings, there would be more than a thousand.
Galileo was the first person to observe the rings of Saturn through his telescope in the year 1610. Due to the constraints that he had at those times with optic, he wasn’t able to clearly define the rings.
However, as time progressed, we got better images of Saturn rings with better satellites.
Voyager One and Voyager Two helped us see the many rings that make up the disk. The most detailed images were sent by Cassini in 2004, which helped the researchers to group them with more accuracy.
When Galileo first observed the Rings, he documented that the rings changed shape, disappeared and appeared with respect to the inclination with the earth.
To easily identify the rings of Saturn, astronomers made them into seven groups. Grouping of Saturn’s Rings has undergone multiple additions every time we received more detailed images.
Currently, the Saturn’s rings are categorized into 7 major groups
- A Ring: Radial width = 14,600 Km | Distance from Saturn’s center = 122,050 - 136,770 Km
- B Ring: Radial width = 25,500 Km | Distance from Saturn’s center = 91,980 - 117,500 Km
- C Ring: Radial width = 17,500 Km | Distance from Saturn’s center = 74,490 - 91,980 Km
- D Ring: Radial width = 7,500 Km | Distance from Saturn’s center = 67,000 - 74,490 Km
- E Ring: Radial width = 300,000 Km | Distance from Saturn’s center = 180,000 - 480,000 Km
- F Ring: Radial width = 30-500 Km | Distance from Saturn’s center = 140,224 Km
- G Ring: Radial width = 8,000 Km | Distance from Saturn’s center = 166,000 - 174,000 Km
Here, The A, B and C rings are the easiest to identify while the D, E, F, and G Rings are fainter and cannot be identified without a sufficiently magnified image or a powerful telescope.
Note: Between these rings, there are also stand gaps which are named and categorized into the Maxwell gap, Colombo Gap, Bond Gap, and more. Hence, the Rings of Saturn is composed of many clusters of rings and gaps.
What are the Rings of Saturn made of?
The composition of the Saturn’s ring comprises of different materials of different sizes. Within the ring, there are rocks and ice particles, all held in place with the Saturn’s gravitational force.
There are many theories to which how Saturn’s Rings were formed, the most famous being the theory that these were formed from the debris resulting from asteroids hitting Saturn’s moons. Saturn has 62 moons, and it was believed that the debris from these moons was caught in Saturn’s gravitational field, causing them to become the rings that we know today.
Other theories claimed that the rings were formed by meteorites that got caught and crushed in the gravitational field of Saturn.
However, these theories fail to explain one thing. The differentiating characteristic of Saturn’s rings when compared with the rings of Neptune or Uranus is that 95% of Saturn’s ring is composed of icy particles while the other two planets have rockier content.
If we believe that crushed moon particles or meteorites were the reason for Saturn’s rings, then we cannot explain why so much of it is ice.
A different theory published at the Southwest Research Institute in Boulder, Colorado, by Robin Canup may answer that very question. The paper states that the Rings of Saturn were formed when Saturn absorbed one of its moons.
To explain the events in more detail, 4.5 billion years ago, when the planets underwent orbital migration, it was the time when the planets captured their moons.
According to the paper, during the moon formation, one of the Saturn’s moon got too close to the planet and started spiraling inwards. As the moon got closer to Saturn, the gravitational pull started to rip the surface ice of the moon.
This event happened over a span of 10,000 years, after which the moon’s core just crashed into Saturn.
This theory was backed up by a computer model simulation which showed the same scenario unfolding over a set course of time. Canup believes that the remaining rock particles in the ring are from meteors that have gone the path of Saturn’s rings.
Saturn’s Rings – How long will they last
Saturn’s Rings are no doubt a wonder to behold, but it may not be forever. A study published in Icarus states that the rings of Saturn are slowly being pulled into Saturn by its strong gravitational pull.
The rings upon entry, disintegrate into ice rain. Compared to earth, Saturn has a slightly more gravitational put at 107% of the earth’s gravitational force. According to the study, the rings of Saturn will last no more than 300 million years.
We are definitely among the people who have seen Saturn in its full glory and beauty, something that far future generations might fail to embrace.