Rings are circular bands of metal, stone or other hard material. They are typically worn on the fingers or on the ear. Some people wear rings as ornaments or as a sign of their status. Other people wear them as a symbol of their love or marriage. A ring can also be used as a memorial to a person who has passed away.
Although rings are generally made of metal, they can be formed of almost any hard material. Ancient Egyptians and Greeks used rings as adornments. Today, modern rings are usually made of sleek steel, with geometric designs etched into them. These rings are also outfitted with small compartments.
The origins of rings are still being debated by scientists. Some believe that the rings around Saturn were created in the early days of the Solar System. Others have proposed that they formed during the breakup of a moon. Another theory is that a large asteroid struck Mars at the time the Solar System was formed. This asteroid likely impacted a planet too close to its center, sending dust and gas particles out into space. When the orbiting debris clumped together, they formed the ring system.
Astronomers have discovered that all four jovian planets have rings. Each ring is unique in its structure. One ring is composed of bits of ice and rock, while another is composed of dust. However, all ring systems have gaps.
The Cassini spacecraft has been studying Saturn’s rings for over a decade. Since the beginning of the mission, scientists have observed a surprising variety of changes in the rings. In 2006, the spacecraft’s instruments began to detect propeller-like features in the rings. This suggests that the ring particles are influenced by the gravitational influence of the surrounding small moons.
Scientists have been able to determine the size and mass of the particles in the rings. The smallest ring particles are the size of dust grains, while the largest are more than twenty meters in diameter. It is estimated that the rings have been around for about 4 billion years. By measuring the mass of the ring particles, scientists are able to make a guess at their composition.
The Cassini mission has sent back clear pictures of the rings, showing their intricate structures. The rings are reflective and appear to illuminate the night side of the planet. Many of the particles within the rings have been recycled for millions of years, and some are believed to be older than the planet itself.
The latest hypothesis about the origins of the rings is that they are the remnants of a moon that was shattered. Scientists have predicted that the gravity of Mars will tear up the closest moon, Phobos, in 30 to 50 million years. Whether these fragments will form new rings or encircle the planet remains unknown.
The Cassini mission also revealed that the ring system has several smaller ringlets. These small moons are believed to produce waves in the ring’s surrounding material, which gives rise to the propeller-like features.