Saturn is one of the largest and most mysterious planets in the solar system. Saturn's rings hide many secrets. For two hundred and fifty years, humanity has tried to answer the question of why they are flat and thin. When this question was answered, dozens of new ones appeared. And each new answer raises more and more questions that continue to multiply as the solar system is explored.
Opening rings
The first to see Saturn’s rings in a telescope was Galileo in 1610. But he took this as an anomaly of the planet. He encrypted his discovery with a Latin anagram, which in translation sounds like: "I watched a triple highest planet." In 1656, Huygens first saw a ring from Saturn. He wrote that Saturn is surrounded by a thin flat ring, nowhere in contact with the planet and inclined to the plane of the ecliptic. Giovanni Cassini in 1675 determined that this is not one solid ring. He spotted two rings that are separated by space. This space was later called the division (or gap) of Cassini.
Research 18-19 centuries
Further studies of Saturn did not bring scientists closer to unraveling the device rings and the causes of their occurrence. Puzzles were just added. For a long time, it was assumed that the planet has two solid and thin rings. Laplace, performing calculations taking into account the influence of the gravitational field, in 1787 concluded that there are many thousands or millions of rings. He believed that the rings were solid and resemble gymnastic hoops.
The French scientist E. Roche determined the minimum distance at which objects can be under the influence of the gravitational field of Saturn. He determined that it is 2.44 radii. (Subsequently, it was called the Roche limit). Closer to this distance, any solid or liquid satellites will be destroyed by the gravitational field. Saturn's rings are located within this radius. The outer size of the rings is 2.3 of the radius of the planet. If they were solid or liquid, the gravitational field would tear them apart.
James Clerk Maxwell participated in a study of the physical structure of rings. His findings say that Saturn’s rings may be composed of small particles. Our compatriot Sofya Kovalevskaya became interested in this problem . She proved that rings can be neither solid nor liquid. Studying Doppler shifts, scientists D. Keeler and W. Campbell found that particles move in orbits that do not contradict the laws of celestial mechanics.
Research in the 20th century
In the fifties of the 20th century, it was found out by spectral analysis that the rings of Saturn contained a lot of frozen water. It was very important. Finally I managed to find out what the rings of Saturn consist of. In addition to ice, methane, sulfur compounds, hydrogen, ammonia, and iron compounds were found in the rings. Exceptional information was obtained from space probes. A Pioneer (1979) and two Voyagers (1980 and 1981) flew past Saturn. In 1997, the Cassini-Huygens mission began. The probe transmitted unique information that will still be analyzed. The Huygens probe landed on Saturn’s largest satellite, Titan, and people on Earth heard the sounds of another world, saw mountains and plains.
Secrets of the rings
Today, a lot of information has been collected about the rings of Saturn. However, a final, consistent model still does not exist. There are questions that are awaiting an answer. Rings were discovered at Uranus and Neptune. Why is such a formation only outside the asteroid belt and not one of the planets of the earth group has? The physical processes that led to the formation of rings are incomprehensible. How did the compression occur and why did hundreds of separate structures form? How do particles of rings not stick together and do not mix? Rings have the properties of a magnetic mirror. Electromagnetic waves of circular polarization are reflected from them. A magnetic field is ejected from ring A. A strong reflection of radio waves is observed. There are spokes in ring B waiting for their explanation. The rings have a low brightness that does not match the design. Near the rings of Saturn, an atmosphere was discovered whose origin is not clear. The so-called density waves and many more phenomena that are waiting for their explanation are noticed.
Hypotheses
In 1986, a hypothesis was put forward about the superconductivity of ice, of which the rings of Saturn consist. Ice is generally a complex formation and, depending on the conditions of occurrence, may have various properties. The presence of superconductivity allows you to create a consistent physical model of Saturn's rings, explaining many anomalies.
How many rings does Saturn have?
There is no final answer to this question either. Today, 13 main rings are distinguished. They are called by the letters of the Latin alphabet: A, B, C, D, etc. The spaces between the rings are called divisions or crevices. There are Cassini divisions, Huygens, Kuiper, Maxwell, and other gaps. The diameter of the rings of Saturn varies from 146 thousand km to 273 thousand km. In 2009, the Phoebe ring was discovered, the existence of the Ray ring is assumed. Their diameters are not yet precisely determined.
Earth observation
Saturn's rings from the Earth can not always be seen. This is due to the fact that the equator of Saturn is strongly inclined to the plane of the orbit around the Sun, and the rings lie in the plane of the equator. The year on Saturn lasts 29.5 Earth years, and during the period when the equinox is on Saturn, its rings disappear for the earth observer. Then for about 7 years they are visible on one side. During the solstice on Saturn, they reach their maximum visibility, and then gradually decrease, up to complete invisibility.
In recent years, planetary astrophysics is booming. Scientists got the opportunity to use data from interplanetary probes, as they say, to practically touch space objects. In the coming years, the rings of Saturn should share their secrets with humanity.