Mass of Saturn in kg. Saturn: the history of a ringed planet

Photo taken from the Cassini spacecraft

The planet Saturn is the sixth planet from the Sun. Everyone knows about this planet. Almost everyone can easily recognize her, because his rings are his business card.

General information about the planet Saturn

Do you know what her famous rings are made of? The rings are composed of ice stones ranging in size from microns to several meters. Saturn, like all giant planets, consists mainly of gases. Its rotation ranges from 10 hours and 39 minutes to 10 hours and 46 minutes. These measurements are based on radio observations of the planet.

Image of the planet Saturn

Using the latest propulsion systems and launch vehicles, the spacecraft will take at least 6 years and 9 months to arrive at the planet.

At the moment, the only Cassini spacecraft has been in orbit since 2004, and it has been the main provider of scientific data and discoveries for many years. For children, the planet Saturn, as well as for adults, is truly the most beautiful of the planets.

General characteristics

The largest planet in the solar system is Jupiter. But the title of the second largest planet belongs to Saturn.

Just for comparison, the diameter of Jupiter is about 143 thousand kilometers, and Saturn is only 120 thousand kilometers. Jupiter is 1.18 times larger than Saturn and 3.34 times more massive in mass.

In fact, Saturn is very large but lightweight. And if the planet Saturn is immersed in water, it will float on the surface. The planet's gravity is only 91% of Earth's.

Saturn and Earth differ in size by 9.4 times and in mass by 95 times. The volume of the gas giant could fit 763 such planets as ours.

Orbit

The time of a complete revolution of the planet around the Sun is 29.7 years. Like all planets in the solar system, its orbit is not a perfect circle, but has an elliptical trajectory. The distance to the Sun is on average 1.43 billion km, or 9.58 AU.

The closest point of Saturn's orbit is called perihelion and it is located 9 astronomical units from the Sun (1 AU is the average distance from the Earth to the Sun).

The most distant point of the orbit is called aphelion and it is located 10.1 astronomical units from the Sun.

Cassini crosses the plane of Saturn's rings.

One of the interesting features of Saturn's orbit is as follows. Like Earth, Saturn's axis of rotation is tilted relative to the plane of the Sun. Halfway through its orbit, Saturn's south pole faces the Sun and then north. During the Saturnian year (almost 30 Earth years), there come periods when the planet is seen from the Earth from the edge and the plane of the giant's rings coincides with our angle of view, and they disappear from sight. The thing is that the rings are extremely thin, so it is almost impossible to see them from the edge from a great distance. The next time the rings will disappear for an Earth observer in 2024-2025. Since the year of Saturn is almost 30 years old, since Galileo first observed it through a telescope in 1610, he has orbited the Sun about 13 times.

Climatic features

One of the interesting facts is that the axis of the planet is tilted to the plane of the ecliptic (like that of the Earth). And just like us, there are seasons on Saturn. Halfway through its orbit, the Northern Hemisphere receives more solar radiation, and then things change and the Southern Hemisphere is bathed in sunlight. This creates huge storm systems that vary significantly depending on the location of the planet in orbit.

Storm in the atmosphere of Saturn. Composite image, artificial colors, MT3, MT2, CB2 filters and infrared data were used

The seasons affect the weather of the planet. Over the past 30 years, scientists have found that wind speeds around the planet's equatorial regions have decreased by about 40%. NASA's Voyager probes in 1980-1981 found wind speeds as high as 1,700 km / h, while currently only about 1,000 km / h (2003 measurements).

The time for a complete revolution of Saturn around its axis is 10.656 hours. It took scientists a lot of time and research to find such an accurate figure. Since the planet has no surface, there is no way to observe the passage of the same regions of the planet, thus estimating its rotation speed. Scientists used radio emissions from the planet to estimate the speed of rotation and find the exact length of the day.

Image gallery

Pictures of the planet taken by the Hubble telescope and the Cassini spacecraft.

Physical properties

Hubble telescope image

Equatorial diameter - 120,536 km, 9.44 times greater than that of the Earth;

The polar diameter is 108,728 km, 8.55 times greater than that of the Earth;

The area of ​​the planet is 4.27 x 10 * 10 km2, which is 83.7 times more than that of the Earth;

Volume - 8.2713 x 10 * 14 km3, 763.6 times more than that of the Earth;

Mass - 5.6846 x 10 * 26 kg, 95.2 times more than that of the Earth;

Density - 0.687 g / cm3, 8 times less than that of the Earth, Saturn is even lighter than water;

This information is incomplete, in more detail about the general properties of the planet Saturn, we will write below.

Saturn has 62 satellites, in fact, about 40% of the satellites in our solar system revolve around it. Many of these satellites are very small and not visible from Earth. The latter were discovered by the Cassini spacecraft, and scientists expect the spacecraft to find even more icy satellites over time.

Despite the fact that Saturn is too hostile for any life form that we know, its companion Enceladus is one of the most suitable candidates for the search for life. Enceladus is notable for having ice geysers on its surface. There is some mechanism (probably the tidal effect of Saturn) that creates enough heat for liquid water to exist. Some scientists believe there is a chance for life to exist on Enceladus.

Formation of the planet

Like the rest of the planets, Saturn formed from a solar nebula about 4.6 billion years ago. This solar nebula was a vast cloud of cold gas and dust that may have collided with another cloud, or supernova shock. This event initiated the beginning of the compression of the protosolar nebula with the further formation of the solar system.

The cloud contracted more and more until a protostar formed in the center, which was surrounded by a flat disk of material. The inner part of this disk contained more heavy elements, and formed the terrestrial planets, while the outer region was quite cold and, in fact, remained untouched.

More and more planetesimals were being formed by the material from the solar nebula. These planetesimals collided together, merging into planets. At some point in Saturn's early history, its moon, roughly 300 km across, was torn apart by its gravity and created rings that still orbit the planet today. In fact, the main parameters of the planet directly depended on the place of its formation and the amount of gas that it was able to capture.

Since Saturn is smaller than Jupiter, it cools faster. Astronomers believe that as soon as its outer atmosphere cooled down to 15 degrees Kelvin, helium condensed into droplets that began to descend towards the core. The friction of these droplets has warmed up the planet, and now it emits about 2.3 times more energy than it receives from the Sun.

Forming rings

Planet view from space

The main distinguishing feature of Saturn is the rings. How did the rings form? There are several versions. The traditional theory is that the rings are almost the same age as the planet itself and have existed for at least 4 billion years. In the early history of the giant, a 300 km satellite came too close to it and was torn to pieces. There is also the possibility that the two satellites collided together, or a sufficiently large comet or asteroid hit the satellite, and it just fell apart right in orbit.

Alternative hypothesis of ring formation

Another hypothesis is that there was no destruction of the satellite. Instead, the rings, as well as the planet itself, were formed from the solar nebula.

But here's the problem: the ice in the rings is too clean. If the rings formed together with Saturn, billions of years ago, then one should expect that they would be completely covered with dirt from the effects of micrometeorites. But today we see that they are as pure as if they were formed less than 100 million years ago.

It is possible that the rings are constantly renewing their material by sticking and colliding with each other, making it difficult to determine their age. This is one of the mysteries that remains to be solved.

Atmosphere

Like the rest of the giant planets, Saturn's atmosphere is made up of 75% hydrogen and 25% helium, with trace amounts of other substances such as water and methane.

Features of the atmosphere

The planet's appearance in visible light looks calmer than that of Jupiter. The planet has streaks of clouds in the atmosphere, but they are pale orange and faintly visible. The orange color is due to sulfur compounds in its atmosphere. In addition to sulfur, there are small amounts of nitrogen and oxygen in the upper atmosphere. These atoms react with each other and, when exposed to sunlight, form complex molecules that resemble smog. At various wavelengths of light, as well as enhanced Cassini images, the atmosphere appears much more dramatic and turbulent.

Winds in the atmosphere

The planet's atmosphere forms some of the fastest winds in the solar system (faster only on Neptune). NASA's Voyager spacecraft, which flew by Saturn, measured the speed of the winds, it was in the region of 1800 km / h at the planet's equator. Large white storms form within stripes that revolve around the planet, but unlike Jupiter, these storms last only a few months and are absorbed by the atmosphere.

The clouds of the visible part of the atmosphere are composed of ammonia, and are located 100 km below the upper part of the troposphere (tropopause), where the temperature drops to -250 ° C. Below this boundary, the clouds are composed of ammonium hydrosulfide and are approximately 170 km lower. In this layer, the temperature is only -70 degrees C. The deepest clouds are water and are located about 130 km below the tropopause. The temperature here is 0 degrees.

The lower, the more the pressure and temperature rises and the hydrogen gas slowly turns into liquid.

Hexagon

One of the strangest weather events ever discovered is the so-called northern hexagonal storm.

The hexagonal clouds around the planet Saturn were first discovered by Voyagers 1 and 2 after they visited the planet more than three decades ago. More recently, Saturn's hexagon has been photographed in great detail using NASA's Cassini spacecraft, currently in orbit around Saturn. The hexagon (or hexagonal vortex) is about 25,000 km in diameter. It can fit 4 such planets as Earth.

The hexagon rotates at exactly the same speed as the planet itself. However, the planet's North Pole is different from the South Pole, which has a huge hurricane at its center with a giant funnel. Each side of the hexagon is about 13,800 km in size, and the entire structure makes one revolution around the axis in 10 hours and 39 minutes, just like the planet itself.

The reason for the formation of the hexagon

So why is the vortex at the North Pole hexagonal? Astronomers find it difficult to answer 100% of this question, but one of the experts and team members in charge of the visual and infrared spectrometer Cassini said: “This is a very strange storm, with precise geometric shapes with six almost identical sides. We have never seen anything like it on other planets. "

Gallery of images of the planet's atmosphere

Saturn - planet of storms

Jupiter is known for its violent storms, which are clearly visible through the upper atmosphere, especially the Great Red Spot. But there are storms on Saturn too, although they are not so large and intense, but compared to Earthly ones, they are simply huge.

One of the largest storms was the Great White Spot, also known as the Great White Oval, which was observed by the Hubble Space Telescope in 1990. Such storms probably appear once a year on Saturn (once every 30 Earth years).

Atmosphere and surface

The planet closely resembles a ball made almost entirely of hydrogen and helium. Its density and temperature change as it moves deeper into the planet.

Atmosphere composition

The outer atmosphere of the planet is composed of 93% molecular hydrogen, the rest helium and trace amounts of ammonia, acetylene, ethane, phosphine and methane. It is these trace elements that create the visible stripes and clouds that we see in the images.

Core

General scheme diagram of the structure of Saturn

According to the theory of accretion, the core of the planet is rocky with a large mass, sufficient to capture a large amount of gases in the early solar nebula. Its core, like that of other gas giants, would have to form and become massive much faster than that of other planets in order to be overgrown with primary gases.

The gas giant most likely formed from rocky or icy components, and the low density indicates admixtures of liquid metal and rock in the core. It is the only planet whose density is lower than that of water. In any case, the internal structure of the planet Saturn is more like a ball made of thick syrup with admixtures of stone fragments.

Metallic hydrogen

The metallic hydrogen in the core generates a magnetic field. The magnetic field created in this way is slightly weaker than that of the Earth and extends only to the orbit of its largest satellite, Titan. Titanium contributes to the appearance of ionized particles in the planet's magnetosphere, which create auroras in the atmosphere. Voyager 2 discovered high pressure from the solar wind on the planet's magnetosphere. According to measurements made during the same mission, the magnetic field extends only over 1.1 million km.

Planet size

The planet has an equatorial diameter of 120,536 km, which is 9.44 times that of the Earth. Its radius is 60,268 km, making it the second largest planet in our solar system, second only to Jupiter. He, like all other planets, is an oblate spheroid. This means that its equatorial diameter is larger than the diameter measured across the poles. In the case of Saturn, this distance is quite significant due to the planet's high rotational speed. The polar diameter is 108728 km, which is 9.796% less than the equatorial diameter, so the shape of Saturn is oval.

Around Saturn

Length of the day

The rotation speed of the atmosphere and the planet itself can be measured by three different methods. The first is to measure the speed of rotation of the planet in the cloud layer in the equatorial part of the planet. It has a rotation period of 10 hours and 14 minutes. If measurements are taken in other regions of Saturn, then the rotation speed will be 10 hours 38 minutes and 25.4 seconds. To date, the most accurate method for measuring the length of a day is based on the measurement of radio emission. This method gives the planet's rotation speed equal to 10 hours 39 minutes and 22.4 seconds. Despite these numbers, the rate of rotation of the interior of the planet at the present time, it is impossible to accurately measure.

Again, the equatorial diameter of the planet is 120,536 km, and the polar diameter is 108,728 km. It is important to know why that this difference in these numbers affects the planet's rotation rate. The situation is the same on other giant planets, especially the difference in the rotation of different parts of the planet is expressed in Jupiter.

The length of the day according to the radio emission of the planet

With the help of radio emission that comes from the inner regions of Saturn, scientists were able to determine its rotation period. Charged particles trapped in its magnetic field emit radio waves when they interact with Saturn's magnetic field, at about 100 kilohertz.

The Voyager probe measured the planet's radio emissions for nine months as it flew by in the 1980s, and the rotation was determined to be 10 hours 39 minutes 24 seconds, with an error of 7 seconds. The Ulysses spacecraft also took measurements 15 years later, and gave a result of 10 hours 45 minutes 45 seconds, with an error of 36 seconds.

It turns out a whole 6 minutes of difference! Either the planet's rotation has slowed down over the years, or we missed something. The Cassini interplanetary probe measured the same radio emissions with a plasma spectrometer, and the scientists found that in addition to the 6-minute difference in 30-year measurements, they found that rotation also changes by one percent per week.

Scientists believe that this may be due to two things: the solar wind coming from the Sun interferes with measurements, and the particles of Enceladus geysers affect the magnetic field. Both of these factors cause the radio emission to vary, and they can cause different results at the same time.

New data

In 2007, it was found that some point sources of radio emission from the planet do not correspond to the rotation speed of Saturn. Some scientists believe that the difference is due to the impact of the satellite Enceladus. Water vapor from these geysers enters the orbit of the planet and is ionized, thereby affecting the planet's magnetic field. This slows down the rotation of the magnetic field, but not significantly compared to the rotation of the planet itself. Current estimates are that Saturn's rotation, based on various measurements from the spacecraft Cassini, Voyager and Pioneer, is 10 hours 32 minutes and 35 seconds as of September 2007.

Key characteristics of the planet, as reported by Cassini, suggest that solar wind is the most likely reason for the difference in data. Differences in the measurements of the rotation of the magnetic field occur every 25 days, which corresponds to the period of the Sun's rotation. The solar wind speed is also constantly changing, which should be taken into account. Enceladus can make long-term changes.

Gravity

Saturn is a giant planet and does not have a solid surface, and what is impossible to see is its surface (we see only the upper cloud layer) and feel the force of gravity. But let's imagine that there is a certain conditional border that will correspond to its imaginary surface. What would be the force of gravity on the planet if you could stand on the surface?

Although Saturn has a greater mass than Earth (the second largest mass in the solar system, after Jupiter), it is also the "lightest" of all the planets in the solar system. The actual force of gravity at any point on its imaginary surface will be 91% of that on Earth. In other words, if your scales show your weight equal to 100 kg on Earth (oh, horror!), On the "surface" of Saturn, you would weigh 92 kg (slightly better, but still).

For comparison, on the "surface" of Jupiter the force of gravity is 2.5 times greater than that of the Earth. On Mars, only 1/3, and on the Moon 1/6.

What makes the force of gravity so weak? The giant planet is mainly composed of hydrogen and helium, which it accumulated at the very beginning of the formation of the solar system. These elements were formed at the beginning of the universe as a result of the Big Bang. This is due to the fact that the planet has an extremely low density.

Planet temperature

Voyager 2 Snapshot

The uppermost layer of the atmosphere, which is located on the border with space, has a temperature of -150 C. But, as it sinks into the atmosphere, the pressure rises and the temperature rises accordingly. In the core of the planet, the temperature can reach 11,700 C. But where is the temperature so high? It is formed due to the huge amount of hydrogen and helium, which, as it sinks into the bowels of the planet, contracts and heats up the core.

Thanks to gravitational contraction, the planet actually generates heat, releasing 2.5 times more energy than it receives from the Sun.

At the bottom of the cloud layer, which is composed of water ice, the average temperature is -23 degrees Celsius. Above this layer of ice is ammonium hydrosulfide, with an average temperature of -93 C. Above it are clouds of ammonia ice that color the atmosphere orange and yellow.

What does Saturn look like and what color is it

Even when viewed through a small telescope, the planet's color is seen as pale yellow with tints of orange. With more powerful telescopes, such as the Hubble, or looking at images taken by NASA's Cassini spacecraft, thin layers of clouds and storms can be seen, consisting of a mixture of white and orange. But what gives Saturn this color?

Like Jupiter, the planet is composed almost entirely of hydrogen, with a small amount of helium, as well as trace amounts of other compounds such as ammonia, water vapor, and various simple hydrocarbons.

Only the upper cloud layer, which mainly consists of ammonia crystals, is responsible for the color of the planet, and the lower cloud layer is either ammonium hydrosulfide or water.

Saturn has a striped atmospheric pattern, much like Jupiter, but these stripes are much fainter and wider around the equator. It also lacks the long-lived storms - nothing like the Great Red Spot - which often occur when Jupiter approaches the northern hemisphere summer solstice.

Some of the photos shared by Cassini appear blue, like Uranus. But this is probably because we see the scattering of light from Cassini's point of view.

Composition

Saturn in the night sky

The rings around the planet have captured the imagination of people for hundreds of years. It was also natural to want to know what the planet is made of. Through various methods, scientists have learned that the chemical composition of Saturn is 96% hydrogen, 3% helium and 1% various elements, which include methane, ammonia, ethane, hydrogen and deuterium. Some of these gases can be found in its atmosphere, in liquid and molten states.

The state of gases changes with increasing pressure and temperature. At the top of the clouds, you will encounter ammonia crystals, at the bottom of the clouds with ammonium hydrosulfide and / or water. Under the clouds, atmospheric pressure increases, which causes the temperature to rise and the hydrogen becomes liquid. As you move deeper into the planet, the pressure and temperature continue to increase. As a result, in the core, hydrogen becomes metallic, passing into this special state of aggregation. The planet is believed to have a loose core, which, in addition to hydrogen, is composed of rock and some metals.

Modern space exploration has led to many discoveries in the Saturn system. Research began with the flyby of the Pioneer 11 spacecraft in 1979. This mission discovered Ring F. Voyager 1 flew by the following year, sending surface details of some of its satellites to Earth. He also proved that the atmosphere on Titan is not transparent to visible light. In 1981, Voyager 2 visited Saturn, and detected changes in the atmosphere, and also confirmed the presence of the Maxwell and Keeler gap, which was first seen by Voyager 1.

After Voyager 2, the Cassini-Huygens spacecraft arrived in the system, which entered orbit around the planet in 2004; you can read more about its mission in this article.

Radiation

When NASA's Cassini spacecraft first arrived on the planet, it detected thunderstorms and radiation belts around the planet. He even found a new radiation belt located inside the planet's ring. The new radiation belt is located 139,000 km from the center of Saturn and extends to 362,000 km.

Northern Lights on Saturn

Video showing the north, created from images from the Hubble Telescope and the Cassini spacecraft.

Due to the presence of a magnetic field, charged particles of the Sun are captured by the magnetosphere and form radiation belts. These charged particles move along the lines of the magnetic force field and collide with the planet's atmosphere. The mechanism of occurrence of the aurora is similar to that of the Earth, but due to the different composition of the atmosphere, the auroras on the giant are purple, in contrast to the green ones on Earth.

Saturn's aurora through the Hubble telescope

Gallery of images of aurora borealis

Nearest neighbors

What is the closest planet to Saturn? It depends on where in the orbit it is at the moment, as well as the position of other planets.

For most of the orbit, the closest planet is. When Saturn and Jupiter are at their minimum distance from each other, they are only 655 million km apart.

When they are located on opposite sides from each other, the planets Saturn sometimes come very close to each other, and at this moment they are separated by 1.43 billion km from each other.

General information

The following planet facts are based on NASA planetary bulletins.

Weight - 568.46 x 10 * 24 kg

Volume: 82,713 x 10 * 10 km3

Average radius: 58232 km

Average diameter: 116 464 km

Density: 0.687 g / cm3

First space speed: 35.5 km / s

Free fall acceleration: 10.44 m / s2

Natural satellites: 62

Distance from the Sun (semi-major axis of the orbit): 1.43353 billion km

Orbital period: 10,759.22 days

Perihelion: 1.35255 billion km

Aphelios: 1.5145 billion km

Orbital speed: 9.69 km / s

Orbit inclination: 2.485 degrees

Orbital eccentricity: 0.0565

Sidereal period of rotation: 10.656 hours

Period of rotation around the axis: 10.656 hours

Axial tilt: 26.73 °

Who discovered: it has been known since prehistoric times

Minimum distance from Earth: 1.1955 billion km

Maximum distance from Earth: 1.6585 billion km

Maximum apparent diameter from Earth: 20.1 arc seconds

Minimum apparent diameter from Earth: 14.5 arc seconds

Apparent magnitude (maximum): 0.43 magnitude

History

Space image taken by the Hubble Telescope

The planet is clearly visible with the naked eye, so it is difficult to tell when the planet was first discovered. Why is the planet called Saturn? It is named after the Roman god of the harvest - this god corresponds to the Greek god Kronos. That is why the origin of the name is Roman.

Galileo

Saturn and its rings were a mystery until Galileo first made his primitive but working telescope and looked at the planet in 1610. Of course, Galileo did not understand what he was seeing and thought that the rings were large satellites on either side of the planet. This was before Christian Huygens used the best telescope to see that they were not actually satellites, but rings. Huygens was also the first to discover the largest satellite, Titan. Despite the fact that the planet's visibility allows it to be observed from almost everywhere, its satellites, like the rings, are visible only through a telescope.

Jean Dominique Cassini

He discovered a gap in the rings, later called Cassini, and was the first to discover 4 satellites of the planet: Iapetus, Rhea, Tethys and Dione.

William Herschel

In 1789, astronomer William Herschel discovered two more moons - Mimas and Enceladus. And in 1848 British scientists discovered a satellite called Hyperion.

Before the spacecraft flew to the planet, we knew not so much about it, despite the fact that you can even see the planet with the naked eye. In the 70s and 80s, NASA launched the Pioneer 11 spacecraft, which became the first spacecraft to visit Saturn, passing 20,000 km from the planet's cloud layer. It was followed by the launches of Voyager 1 in 1980, and Voyager 2 in August 1981.

In July 2004, NASA's Cassini spacecraft arrived in the Saturn system, and compiled the most detailed description of the planet Saturn and its system based on the results of observations. Cassini has flown nearly 100 orbits around Titan's moon, several times around many other moons, and has sent us thousands of images of the planet and its moons. Cassini discovered 4 new moons, a new ring, and discovered seas of liquid hydrocarbons on Titan.

Extended animation of Cassini flight in the Saturn system

Rings

They are composed of ice particles orbiting the planet. There are several main rings that are clearly visible from Earth and astronomers use special designations for each of Saturn's rings. But how many rings does the planet Saturn actually have?

The Rings: View from Cassini

We will try to answer this question. The rings themselves are divided into the following parts. The two densest parts of the ring are designated A and B, they are separated by a Cassini slit, followed by ring C. After the 3 main rings, there are smaller dust rings: D, G, E, as well as ring F, which is the outermost ... So how many base rings are there? That's right - 8!

These three main rings and 5 dust rings make up the bulk. But there are a few more rings, for example Janus, Meton, Pallen, as well as the arcs of the Anfa ring.

There are also smaller rings and gaps in various rings that are difficult to count (for example, the Encke gap, Huygens gap, Dawes gap, and many others). Further observation of the rings will make it possible to clarify their parameters and number.

Disappearing rings

Due to the inclination of the planet's orbit, the rings become visible edge-on every 14-15 years, and due to the fact that they are very thin, they actually disappear from the field of view of Earth observers. In 1612, Galileo noticed that the satellites he discovered had disappeared somewhere. The situation was so strange that Galileo even abandoned observations of the planet (most likely as a result of the collapse of hopes!). He had discovered the rings (and mistook them for companions) two years earlier and was instantly fascinated by them.

Ring parameters

The planet is sometimes called the “pearl of the solar system” because its ring system looks like a corona. These rings are composed of dust, stone and ice. That is why the rings do not disintegrate, because it is not integral, but consists of billions of particles. Some of the material in the ring system is the size of grains of sand, and some objects are larger than high-rise buildings, reaching a kilometer in diameter. What are rings made of? Mostly ice particles, although there are dust rings. It is striking that each ring rotates at a different speed in relation to the planet. The average density of the planet's rings is so low that stars can be seen through them.

Saturn is not the only planet with a ring system. All gas giants have rings. Saturn's rings stand out because they are the largest and brightest. The rings are approximately one kilometer thick and span an area up to 482,000 kilometers from the center of the planet.

The names of the rings of Saturn are listed alphabetically according to the order in which they were found. This makes the rings a little confusing, listing them out of order from the planet. Below is a list of the main rings and the spaces between them, as well as the distance from the center of the planet and their width.

Ring sounds

In this great video, you hear the sounds of the planet Saturn, which is the planet's radio emission translated into sound. Kilometer-range radio emissions are generated along with the auroras on the planet.

The Cassini Plasma Spectrometer performed high-resolution measurements that allowed scientists to convert radio waves into audio by shifting frequency.

The appearance of the rings

How did the rings come about? The simplest answer to why the planet has rings and what they are made of is that the planet has accumulated a lot of dust and ice at various distances from itself. These elements were most likely trapped by gravity. Although some believe that they were formed as a result of the destruction of a small satellite that came too close to the planet and fell into the Roche limit, as a result of which it was torn to pieces by the planet itself.

Some scientists speculate that all the material in the rings is the product of collisions between satellites and asteroids or comets. After the collision, the remnants of the asteroids were able to escape the planet's gravitational pull and formed rings.

Regardless of which of these versions is correct, the rings are quite impressive. In fact, Saturn is the lord of the rings. After exploring the rings, it is necessary to study the ring systems of other planets: Neptune, Uranus and Jupiter. Each of these systems is weaker, but still interesting in its own way.

Ring Snapshot Gallery

Life on Saturn

It is difficult to imagine a less hospitable planet for life than Saturn. The planet is made up almost entirely of hydrogen and helium, with trace amounts of water ice in the lower cloud. The temperature at the top of the clouds can drop to -150 C.

As you descend into the atmosphere, the pressure and temperature will increase. If the temperature is warm enough so that the water does not freeze, then the atmospheric pressure at this level is the same as a few kilometers under the Earth's ocean.

Life on the satellites of the planet

To find life, scientists suggest looking at the satellites of the planet. They are made up of significant amounts of water ice, and their gravitational interaction with Saturn likely keeps their insides warm. The satellite Enceladus is known to have geysers of water on its surface that erupt almost continuously. It is possible that it has huge reserves of warm water under the ice crust (almost like Europe).

Another moon, Titan, has lakes and seas of liquid hydrocarbons and is considered a place that could potentially create life. Astronomers believe that Titan is very similar in composition to Earth in its early history. After the Sun turns into a red dwarf (in 4-5 billion years), the temperature on the satellite will become favorable for the origin and maintenance of life, and a large amount of hydrocarbons, including complex ones, will be the primary “soup”.

Position in the sky

Saturn and its six moons, amateur shot

Saturn is visible in the sky as a rather bright star. The current coordinates of the planet are best clarified in specialized planetarium programs, for example, Stellarium, and events related to its coverage or passage over a particular region, as well as everything about the planet Saturn, can be spied on in the article 100 astronomical events of the year. The confrontation of the planet always provides a chance to look at it in maximum detail.

The nearest confrontation

Knowing the ephemeris of the planet and its magnitude, it will not be difficult to find Saturn in the starry sky. However, if you have little experience, it can take a long time to find it, so we recommend using amateur telescopes with a Go-To mount. Use a telescope with a Go-To mount and you don't need to know the coordinates of the planet or where you can see it now.

Flight to the planet

How long will the space travel to Saturn take? Depending on which route you take, the flight may take a different amount of time.

For example: Pioneer 11 took six and a half years to reach the planet. Voyager 1 took three years and two months, Voyager 2 took four years, and the Cassini spacecraft six years and nine months! The New Horizons spacecraft used Saturn as a gravitational springboard on its way to Pluto, and arrived there two years and four months after launch. Why is there such a huge difference in flight times?

The first factor that determines flight time

Let's consider, is the spacecraft launched directly to Saturn or is it simultaneously using other celestial bodies as a slingshot?

The second factor that determines flight time

This is a type of spacecraft engine, and the third factor is whether we are going to fly over the planet or enter its orbit.

With these factors in mind, let's take a look at the missions mentioned above. Pioneer 11 and Cassini used the gravitational influence of other planets before heading towards Saturn. These flights of other bodies added extra years to an already long trip. Voyager 1 and 2 used only Jupiter on their way to Saturn and arrived at it much faster. The New Horizons ship had several distinct advantages over all other probes. Two main advantages are that it has the fastest and most advanced engine and was launched on a short trajectory to Saturn on its way to Pluto.

Research stages

Panoramic photograph of Saturn taken on July 19, 2013 by the Cassini apparatus. In the empty ring on the left - the white dot is Enceladus. The earth is visible below and to the right of the center of the image.

In 1979, the first spacecraft reached the giant planet.

Pioneer 11

Created in 1973, Pioneer 11 circled Jupiter and used the planet's gravity to alter its trajectory towards Saturn. He arrived to him on September 1, 1979, having passed 22,000 km above the cloud layer of the planet. For the first time in history, he conducted close-up studies of Saturn and transmitted close-up photographs of the planet, discovering a previously unknown ring.

Voyager 1

NASA's Voyager 1 probe was the next spacecraft to visit the planet on November 12, 1980. It flew 124,000 km from the planet's cloud layer, and sent a stream of truly priceless photographs to Earth. They decided to send Voyager 1 to fly around the satellite of Titan, and send his twin brother Voyager 2 to other giant planets. As a result, it turned out that the device, although it transmitted a lot of scientific information, did not see the surface of Titan, since it is opaque to visible light. Therefore, in fact, the ship was donated to please the largest satellite, on which scientists had high hopes, and in the end they saw an orange ball, without any details.

Voyager 2

Shortly after the Voyager 1 flyby, Voyager 2 flew into the Saturn system and performed an almost identical program. It reached the planet on August 26, 1981. In addition to the fact that he orbited the planet at a distance of 100 800 km, he flew close to Enceladus, Tethys, Hyperion, Iapetus, Phoebe and a number of other moons. Voyager 2, having received gravitational acceleration from the planet, headed towards Uranus (successful flyby in 1986) and Neptune (successful flyby in 1989), after which he continued his journey to the borders of the solar system.

Cassini-Huygens

Views of Saturn from the Cassini apparatus

NASA's Cassini-Huygens probe, which arrived in 2004, was able to truly study the planet from a constant orbit. As part of its mission, the spacecraft delivered the Huygens probe to the surface of Titan.

TOP 10 images of Cassini

Cassini has now completed his main mission and has continued to study the Saturn system and its moons for many years. Among his discoveries are the discovery of geysers on Enceladus, seas and lakes of hydrocarbons on Titan, new rings and satellites, as well as data and photographs from the surface of Titan. Scientists plan to complete the Cassini mission in 2017, due to cuts in NASA's planetary exploration budget.

Future missions

The next Titan Saturn System Mission (TSSM) should be expected no earlier than 2020, but rather much later. Using gravitational maneuvers near Earth and Venus, this device will be able to reach Saturn in about 2029.

A four-year flight plan is envisaged, in which 2 years are allotted for the study of the planet itself, 2 months for the study of the surface of Titan, in which the lander will be involved and 20 months for the study of the satellite from orbit. Russia will probably take part in this truly ambitious project. The future participation of the federal agency Roscosmos is already being discussed. While this mission is far from being realized, we still have the opportunity to enjoy the fantastic pictures of Cassini, which he sends regularly and which everyone has access to, just a few days after their transmission to Earth. Enjoy your exploration of Saturn!

Answers to the most common questions

1. After whom was the planet Saturn named? In honor of the Roman god of fertility.
2. When was Saturn discovered? It has been known since ancient times, and it is impossible to establish who first determined that this is a planet.
3. How far is Saturn from the Sun? The average distance from the Sun is 1.43 billion km, or 9.58 AU.
4. How to find it in the sky? It is best to use search charts and specialized software such as Stellarium.
5. What are the coordinates of the placenta? Since this is a planet, its coordinates change, you can find out the ephemerides of Saturn on specialized astronomical resources.

The planet Saturn is one of the brightest objects in our starry sky. Its distinctive feature is the presence of rings. For the first time, G. Galileo saw them in 1610, but did not understand what it was, having written down that Saturn consists of parts.

Half a century later, the Dutch mathematician, physicist and astronomer Christian Huygens(1629-1695) reported that Saturn had a ring, and in 1675 the famous Italian and French astronomer Jean Dominique Cassini(1625-1712) discovered a gap between the rings.

These rings are visible from Earth even with a small telescope. They are made up of thousands upon thousands of small solid pieces of rock and ice that orbit the planet. Once every 14-15 years, the rings of Saturn are not visible from Earth, as they turn edge-on.

General characteristics of the planet Saturn

Therefore, Saturn is not a solid ball, but consists of gas and liquid, its equatorial parts rotate faster than the circumpolar regions: at the poles, one revolution is completed about 26 minutes slower.

One of the features of Saturn is that it is the only planet in the solar system whose density is less than that of water. Saturn's atmosphere is very dense, composed of 94% hydrogen and 6% helium. The temperature on the surface of the planet is 150 ° С.

The speed of the winds on Saturn depends on the latitude of the place, reaching 500 m / s, which is three times more than on Jupiter. Storms are frequent in Saturn's atmosphere, although not as powerful as Jupiter's famous Red Spot. In particular, the Great Brown Spot has been discovered on Saturn.

The planet has eight large main and many small satellites.

Most of the satellites consist of ice: their density does not exceed 1400 kg / m 3. The largest satellites have a rocky core. Almost all satellites are always turned to the planet with one side.

The largest moon of Saturn is Titan. In terms of its size, it surpasses the planet Mercury. Its diameter is 5150 km. It was opened in 1655 by Christian Huygens. Titan has oceans, seas, continents. The temperature is 180 ° C. This moon is shrouded in an orange atmosphere of methane and ethane.

The satellite Enceladus is the lightest body in the solar system, which, apparently, is covered with a thin layer of frost. The two largest craters on this moon of Saturn are named after Ali Baba and Aladdin.

Hyperion is a dark, irregularly shaped satellite with a chaotic proper rotation. It does not have a constant speed of rotation around its axis: it changes by tens of percent during the month.

Saturn's moon Phoebus revolves around the planet in the opposite direction.

It is the second largest after Jupiter, has a huge mass and a dense layer of rings that surround it. The atmosphere of Saturn is a phenomenon that has been the subject of controversy among scientists for many years. But today it has been reliably established that it is gases that form the basis of the entire air body, which does not have a solid surface.

History of the great discovery

For a long time, scientists believed that our system is closed by this huge planet, and there is nothing beyond its orbit. They have been studying it since the distant 1610, after Galileo examined Saturn through a telescope, and also highlighted the presence of rings in his notes. In those years, no one could have thought that this celestial body is so different from Earth, Venus or Mars: it does not even have a surface and consists entirely of gases heated to unimaginable temperatures. The presence of the atmosphere of Saturn was confirmed only in the twentieth century. Moreover, only modern scientists were able to conclude that the planet is a gas sphere.

It was investigated by the Voyager 1 satellite, which was able to release a probe into the outer. Images were obtained that indicated the content of mainly hydrogen in the clouds of Saturn, as well as many other gases. Since then, research has been conducted only on the basis of theories and calculations. And here it will be fair to say that Saturn is one of the most mysterious and unexplored planets up to the present moment.

The presence of the atmosphere, its composition

We know that the terrestrial planets that are in close proximity to the Sun do not have an atmosphere. But these are solid bodies that consist of stone and metal, have a certain mass and the corresponding parameters. With gas balls, things are very different. The atmosphere of Saturn is the foundation of himself. Endless gas vapors, fogs and clouds gather in incredible quantities and form a ball thanks to the magnetic field of the core.

The basis of the planet's atmosphere is hydrogen: over 96 percent. Other gases are present as impurities, the proportions of which depend on the depth. It should be noted that there are no crystals of water, various modifications of ice and other organic substances on Saturn.

The two layers of the atmosphere and their composition

So, the atmosphere of Saturn is divided into two parts: the outer layer and the inner one. The first is 96.3 percent molecular hydrogen and 3 percent helium. These main gases are mixed with components such as phosphine, ammonia, methane and ethane. Here there are strong surface areas which reach 500 m / s. As for the lower atmosphere, metallic hydrogen prevails here - about 91 percent, as well as helium. In this environment, there are clouds of ammonium hydrosulfide. The lower atmospheric layer is always heated to the limit. As it approaches the core, the temperature reaches a thousand Kelvin, because so far it is impossible to explore the planet using probes made in terrestrial conditions.

Atmospheric phenomena

The most common phenomena on this planet are winds and hurricanes. Most streams blow from west to east with respect to axial rotation. There is a slight lull in the equator area, and with distance from it, western flows appear. There are also places on Saturn where certain things happen at regular intervals. For example, the Great White Oval appears in the southern hemisphere once every thirty years. During such "bad weather" the atmosphere of Saturn, whose composition further contributes to this phenomenon, is literally permeated with lightning. Discharges occur mainly in mid-latitudes, between the equator and the poles. As for the latter, the main phenomenon here is considered Stronger flares occur in the north, since there the magnetic field is stronger than in the south. The radiance appears in the form of oval rings or spirals.

Pressure and temperature

As it turned out, Saturn's atmosphere makes this planet cool enough compared to Jupiter, but certainly not as icy as Uranus and Neptune. In the upper layers, the temperature is around -178 degrees Celsius, taking into account the constant winds and hurricanes. The closer we move to the core, the more pressure increases, hence the temperature rises. In the middle layers, it is -88 degrees, and the pressure is about a thousand atmospheres. The extreme point that the probe reached was a temperature zone of -3. According to calculations in the area of ​​the planet's core, the pressure reaches 3 million atmospheres. In this case, the temperature is 11 700

Afterword

We briefly examined what is the structure of the atmosphere of Saturn. Its composition can be compared with that of Jupiter; there are also similarities with the ice giants - Uranus and Neptune. But, like every ball of gas, Saturn is unique in its structure. Very strong winds blow here, the pressure reaches incredible values, and the temperature remains cool (by astronomical standards).

One of the most beautiful astronomical objects for observation is undoubtedly the planet with rings - Saturn. It is difficult to disagree with this statement if at least once it was possible to look at the ringed giant through the lens of a telescope. However, this object of the solar system is interesting not only from the point of view of aesthetics.

Why does the sixth planet from the Sun have a system of rings, and why did it get such a bright attribute? Astrophysicists and astronomers are still trying to get an answer to these and many questions.

Brief characteristics of the planet Saturn

Like other gas giants in our near space, Saturn is of interest to the scientific community. The distance from the Earth to it varies in the range of 1.20-1.66 billion kilometers. In order to overcome this huge and long path, spacecraft launched from our planet will take a little more than two years. The newest automatic probe "New Horizons" reached the sixth planet for two years and four months. It should be borne in mind that the movement of the planet around the Sun is similar to the orbital movement of the Earth. In other words, Saturn's orbit is in the shape of a perfect ellipse. It has the third largest orbital eccentricity, after Mercury and Mars. The distance from the Sun at perihelion is 1,353,572,956 km, while at aphelion the gas giant moves away a little, being at a distance of 1,513,325,783 km.

Even at such a significant distance from the central star, the sixth planet behaves quite briskly, rotating around its own axis at a tremendous speed of 9.69 km / s. The rotation period of Saturn is 10 hours and 39 minutes. According to this indicator, it is second only to Jupiter. This high rotation speed makes the planet appear flattened from the poles. Visually, Saturn resembles a top spinning at a staggering speed, which rushes through the vastness of space at a speed of 9.89 km / s, making a full revolution around the Sun in almost 30 Earth years. Since the discovery of Saturn in 1610 by Galileo, the celestial body has only wrapped around the main star of the solar system 13 times.

The planet looks in the night sky, like a fairly bright point, the apparent magnitude of which varies from +1.47 to -0.24. The rings of Saturn are especially visible, which have a high albedo.

The location of Saturn in space is also curious. The axis of rotation of this planet has almost the same inclination to the axis of the ecliptic as that of the Earth. In this regard, there are seasons on the gas giant.

Saturn is not the largest planet in the solar system, but only the second largest celestial object in our closest space after Jupiter. The average radius of the planet is 58.232 km, versus 69 911 km. near Jupiter. In this case, the polar diameter of the planet is less than the equatorial value. The mass of the planet is 5.6846 · 10²⁶ kg, which is 96 times the mass of the Earth.

The closest planets to Saturn are its brothers in the planetary group - Jupiter and Uranus. The first belongs to the gas giants, while Uranus is ranked among the ice giants. The two gas giants Jupiter and Saturn are characterized by huge mass combined with low density. This is due to the fact that both planets are giant spherical lumps of liquefied gas. The density of Saturn is 0.687 g / cm³, inferior in this indicator to all the planets of the solar system.

For comparison, the density of the terrestrial planets Mars, Earth, Venus and Mercury is 3.94 g / cm³, 5.515 g / cm³, 5.25 g / cm³ and 5.42 g / cm³, respectively.

Description and composition of Saturn's atmosphere

The surface of a planet is a conditional concept, the sixth planet has no earthly solid. It is likely that the surface is the bottom of a hydrogen-helium ocean, where, under the influence of monstrous pressure, the gas mixture turns into a semi-liquid and liquid state. At the moment, there are no technical means to explore the surface of the planet, so all assumptions about the structure of the gas giant look purely theoretical. The object of study is the atmosphere of Saturn, which envelops the planet in a dense blanket.

The planet's air envelope is mainly composed of hydrogen. It is hydrogen and helium that are the chemical elements that keep the atmosphere in constant motion. This is evidenced by the large area cloud formations, consisting of ammonia. Due to the fact that the smallest particles of sulfur are present in the air-gas mixture, Saturn has an orange color from the side. The overcast zone begins at the lower border of the troposphere - at an altitude of 100 km. from the imaginary surface of the planet. Temperatures in this area range from 200-250⁰ Celsius below zero.

More accurate data on the composition of the atmosphere are as follows:

• hydrogen 96%;
• helium 3%;
• methane is only 0.4%;
• ammonia accounts for 0.01%;
• molecular hydrogen 0.01%;
• 0.0007% is ethane.

In terms of its density and massiveness, the clouds on Saturn look more powerful than on Jupiter. In the lower part of the atmosphere, the main components of the Saturnian cloud are ammonium hydrosulfite or water, in various variations. The presence of water vapor in the lower parts of Saturn's atmosphere, at altitudes less than 100 km, also allows the temperature, which in this area is within absolute zero. The atmospheric pressure in the lower parts of the atmosphere is 140 kPa. As we approach the surface of a celestial body, the temperature and pressure begin to rise. Gaseous compounds are transformed, forming new forms. Due to the high pressure, hydrogen takes on a semi-liquid state. The approximate average temperature on the surface of the hydrogen-helium ocean is 143K.

This state of the air-gas envelope has become the reason that Saturn is the only planet in the solar system that gives off more heat to the surrounding space than it receives from our Luminary.

Saturn, being at a distance of one and a half billion kilometers from the Sun, receives 100 times less solar heat than the Earth.

Saturn's stove is explained by the operation of the Kelvin-Helmholtz mechanism. With a drop in temperature, the pressure in the layers of the planet's atmosphere also decreases. The celestial body involuntarily begins to shrink, converting the potential energy of compression into heat. Another assumption explaining the intense release of heat by Saturn is a chemical reaction. As a result of convection in the layers of the atmosphere, condensation of helium molecules in the layers of hydrogen occurs, accompanied by the release of heat.

Dense cloud masses, temperature differences in the layers of the atmosphere, contribute to the fact that Saturn is one of the windiest regions of the solar system. Storms and hurricanes are much stronger and more powerful here than on Jupiter. The air speed in some cases reaches a whopping 1800 km / h. Moreover, Saturnian storms are forming rapidly. The onset of a hurricane on the planet's surface can be traced visually by observing Saturn through a telescope for several hours. However, following the rapid emergence, a long period of rampage of the cosmic element begins.

The structure of the planet and a description of the core

With increasing temperature and pressure, hydrogen is gradually transformed into a liquid state. At approximately a depth of 20-30 thousand km, the pressure is 300 GPa. Under these conditions, hydrogen begins to metallize. As you go deeper into the bowels of the planet, the proportion of compounds of oxides with hydrogen begins to increase. Metallic hydrogen makes up the outer shell of the core. This state of hydrogen contributes to the emergence of high-intensity electric currents, forming the strongest magnetic field.

Unlike the outer layers of Saturn, the inner part of the core is a massive formation with a diameter of 25 thousand kilometers, consisting of compounds of silicon and metals. Presumably in this area, temperatures reach 11 thousand degrees Celsius. The mass of the core varies in the range of 9-22 masses of our planet.

Saturn's moons and rings

Saturn has 62 moons, and most of them have a hard surface and even have their own atmosphere. In terms of their size, some of them can lay claim to the title of the planet. Just take the size of Titan, which is one of the largest satellites in the solar system and larger than the planet Mercury. This celestial body orbiting Saturn has a diameter of 5150 km. The satellite has its own atmosphere, which in its composition strongly resembles the air shell of our planet at an early stage of formation.

Scientists believe that Saturn has the most advanced satellite system in the entire solar system. According to information received from the Cassini automatic interplanetary station, Saturn is almost the only place in the solar system where liquid water can exist on its satellites. To date, only some of the satellites of the ringed giant have been investigated, however, even the information that is available gives every reason to consider this most distant part of the near space suitable for the existence of certain life forms. In this regard, the fifth satellite, Enceladus, is of great interest to astrophysicists.

The main decoration of the planet is undoubtedly its rings. It is customary to distinguish four main rings in the system, which have the corresponding names A, B, C and D. The width of the largest ring B is 25,500 km. The rings are separated by slots, among which the largest is the Cassini division, delimiting rings A and B. According to their composition, the Saturnian rings are accumulations of small and large particles of water ice. Due to the icy structure, Saturn's halos have a high albedo, and therefore are clearly visible through a telescope.

Finally

Advances in science and technology in the past 30 years have allowed scientists to more intensively conduct research on a distant planet using technical means. Following the first information obtained as a result of the flight of the American spacecraft "Pioneer 11", which first flew near the gas giant in 1979, Saturn was closely tackled.

In the early 80s, the Pioneer mission was continued by two Voyagers, the first and the second. Research has focused on the moons of Saturn. In 1997, earthlings for the first time received a sufficient amount of information about Saturn and the system of this planet thanks to the AMS Cassini-Huygens mission. The flight program included the landing of the Huygens probe on the surface of Titan, which was successfully completed on January 14, 2005.

Saturn is the sixth planet from the Sun in the solar system, one of the giant planets. A characteristic feature of Saturn, its decoration, is a system of rings, consisting mainly of ice and dust. It has many satellites. Saturn was named by the ancient Romans in honor of the god of agriculture they especially revered.

a brief description of

Saturn is the second largest planet in the solar system after Jupiter, with a mass of approximately 95 Earth masses. Saturn revolves around the Sun at an average distance of about 1430 million kilometers. The distance to the Earth is 1280 million km. Its circulation period is 29.5 years, and a day on the planet lasts ten and a half hours. The composition of Saturn practically does not differ from that of the sun: the main elements are hydrogen and helium, as well as numerous impurities of ammonia, methane, ethane, acetylene and water. In terms of its internal composition, it is more reminiscent of Jupiter: a core of iron, water and nickel, covered with a thin shell of metallic hydrogen. An atmosphere of huge amounts of gaseous helium and hydrogen envelops the core in a thick layer. Since the planet consists mainly of gas, and there is no solid surface, Saturn is ranked among the gas giants. For the same reason, its average density is incredibly low - 0.687 g / cm 3, which is less than the density of water. This makes it the least dense planet in the system. However, the compression ratio of Saturn, on the contrary, is the highest. This means that its equatorial and polar radii differ greatly in magnitude - 60,300 km and 54,400 km, respectively. This also implies a large difference in velocities for different parts of the atmosphere, depending on latitude. The average rotation speed around the axis is 9.87 km / s, and the orbital speed is 9.69 km / s.

Saturn's ring system is a magnificent sight. They consist of fragments of ice and stones, dust, remnants of former satellites destroyed by its gravitational
field. They are located very high above the equator of the planet, about 6 - 120 thousand kilometers. However, the rings themselves are very thin: each of them is about a kilometer thick. The whole system is divided into four rings - three main and one thinner. The first three are usually denoted in Latin letters. The middle ring B, the brightest and widest, is separated from ring A by a space called the Cassini cleft, in which the thinnest and most transparent rings are located. It is little known that in fact all four giant planets have rings, but they are almost invisible in all except Saturn.

Currently, there are 62 known satellites of Saturn. The largest of them are Titan, Enceladus, Mimas, Tethys, Dione, Iapetus and Rhea. Titan, the largest of the satellites, is similar in many ways to Earth. It has an atmosphere divided into layers, as well as a liquid on the surface, which is already a proven fact. Smaller objects are believed to be asteroid debris and may be less than a kilometer in size.

Formation of the planet

There are two hypotheses about the origin of Saturn:

The first - the "contraction" hypothesis - says that the sun and the planets were formed in the same way. At the initial stages of its development, the solar system was a disk of gas and dust, in which separate areas were gradually formed, denser and more massive than the substance surrounding them. As a result, these "condensations" gave rise to the Sun and the planets known to us. This explains the similarity of the composition of Saturn and the Sun and its low density.

According to the second "accretion" hypothesis, the formation of Saturn proceeded in two stages. The first is the formation of dense bodies in the gas-dust disk, like the solid planets of the terrestrial group. At this time, part of the gases in the region of Jupiter and Saturn scattered into outer space, which explains the small difference in the composition of these planets with the Sun. In the second stage, larger bodies attracted gas from the surrounding cloud.

Internal structure

The inner region of Saturn is divided into three layers. In the center there is a small, compared to the total volume, but a massive core of silicates, metals and ice. Its radius is about a quarter of the planet's radius, and its mass ranges from 9 to 22 Earth masses. The core temperature is about 12,000 ° C. The energy emitted by the gas giant is 2.5 times the energy it receives from the sun. There are several reasons for this. First, the source of internal heat can be the energy reserves accumulated during the gravitational compression of Saturn: during the formation of a planet from a protoplanetary disk, the gravitational energy of dust and gas passed into kinetic energy, and then into heat. Secondly, part of the heat is created due to the Kelvin-Helmholtz mechanism: with a drop in temperature, the pressure also drops, due to which the matter of the planet is compressed, and potential energy turns into heat. Third, as a result of condensation of helium droplets and their subsequent fall through the hydrogen layer into the core, heat can also be generated.

The core of Saturn is surrounded by a layer of hydrogen in a metallic state: it is in the liquid phase, but has the properties of a metal. Such hydrogen has a very high electrical conductivity, therefore, the circulation of currents in it creates a powerful magnetic field. Here, at a depth of about 30 thousand km, the pressure reaches 3 million atmospheres. Above this level, there is a layer of liquid molecular hydrogen, which gradually becomes a gas with height, in contact with the atmosphere.

Atmosphere

Since gas planets do not have a solid surface, it is difficult to pinpoint exactly where the atmosphere begins. For Saturn, such a zero level is the altitude at which methane boils. The main components of the atmosphere are hydrogen (96.3%) and helium (3.25%). Also, spectroscopic studies have found in its composition water, methane, acetylene, ethane, phosphine, ammonia. The pressure at the upper boundary of the atmosphere is about 0.5 atm. At this level, ammonia condenses and white clouds form. At the bottom, the clouds are composed of ice crystals and water droplets.

Gases in the atmosphere are constantly moving, as a result of which they take the form of stripes parallel to the diameter of the planet. There are similar stripes on Jupiter, but on Saturn they are much dimmer. Convection and rapid rotation generate incredibly strong winds, the most powerful in the solar system. The winds mainly blow in the direction of rotation, to the east. At the equator, the air currents are the strongest, their speed can reach 1800 km / h. With distance from the equator, the winds weaken, and westerly flows appear. The movement of gases occurs in all layers of the atmosphere.

Large cyclones can be very persistent and last for years. Once every 30 years on Saturn there is a "Great White Oval" - a super-powerful hurricane, the size of which becomes larger each time. At the time of its last observation in 2010, it made up a quarter of the entire disk of the planet. Also, interplanetary stations discovered an unusual formation in the form of a regular hexagon at the North Pole. Its shape has been stable for 20 years after the first observation. Each side is 13,800 km - more than the diameter of the Earth. For astronomers, the reason for the formation of just such a form of clouds is still a mystery.

Voyager and Cassini cameras recorded the glowing regions on Saturn. They turned out to be the aurora borealis. They are located at a latitude of 70-80 ° and look like very bright oval (less often spiral) rings. It is believed that auroras on Saturn are formed as a result of the rearrangement of the magnetic field lines. As a result, the magnetic energy heats up the surrounding regions of the atmosphere and accelerates the charged particles to high speeds. In addition, lightning strikes are observed during strong storms.

Rings

When we talk about Saturn, the first thing that comes to mind is its amazing rings. Observations of spacecraft have shown that all gas planets have rings, but only at Saturn they are clearly visible and pronounced. The rings are composed of the smallest particles of ice, rocks, dust, meteorite debris, pulled in by the gravity of the system from outer space. They are more reflective than the disc of Saturn itself. The ring system consists of three main and a thinner fourth. Their diameter is about 250,000 km and their thickness is less than 1 km. The rings are named by letters of the Latin alphabet in order, from the periphery to the center. Rings A and B are separated by a space 4000 km wide, called the Cassini gap. There is also a gap inside the outer ring A - the Encke dividing strip. Ring B is the brightest and widest, and C is almost transparent. Fainter and closest to the outer part of Saturn's atmosphere, rings D, E, F, G were discovered later. After the space stations took pictures of the planet, it became clear that, in fact, all large rings consist of many thinner rings.

There are several theories about the origin and formation of Saturn's rings. According to one of them, the rings were formed as a result of the planet's "capture" of some of its satellites. They collapsed, and their fragments were evenly distributed in orbit. The second says that the rings formed with the planet itself from the original cloud of dust and gas. The particles that make up the rings cannot form larger objects like satellites due to their too small size, erratic movement and collisions with each other. It is worth noting that the system of Saturn's rings is not considered absolutely stable: part of the matter is lost, absorbed by the planet or scattered into near-planetary space, and part, on the contrary, is compensated for by the interaction of comets and asteroids with the gravitational field.

Of all the gas giants, Saturn has the most similarities with Jupiter in structure and composition. A significant part of both planets is an atmosphere of a mixture of hydrogen and helium, as well as some other impurities. Such an elemental composition practically does not differ from that of the sun. Under a thick layer of gases is a core of ice, iron and nickel, covered with a thin shell of metallic hydrogen. Saturn and Jupiter emit more heat than they receive from the Sun, since about half of the energy they radiate is due to internal heat flows. Thus, Saturn could become the second star, but he did not have enough substance to create sufficient gravitational force to facilitate thermonuclear fusion.

Modern space observations have shown that clouds at the north pole of Saturn form a giant regular hexagon, the length of each side of which is 12.5 thousand km. The structure rotates with the planet and has not lost its shape for 20 years since its first discovery. A similar phenomenon is not observed anywhere else in the solar system, and scientists still have not been able to explain it.

Voyager spacecraft have detected strong winds on Saturn. Air flow speeds reach 500 m / s. The winds blow mainly in the easterly direction, although with distance from the equator their strength weakens and flows directed to the west appear. Some data indicate that the circulation of gases occurs not only in the upper atmosphere, but also at depth. Also in the atmosphere of Saturn, hurricanes of colossal power periodically appear. The largest of these, the Big White Oval, appears once every 30 years.

Now in the orbit of Saturn is the interplanetary station "Cassini", controlled from the Earth. It was launched in 1997 and reached the planet in 2004. Its purpose is to study the rings, atmosphere and magnetic field of Saturn and its moons. Thanks to Cassini, many high-quality images were obtained, auroras, the aforementioned hexagon, mountains and islands on Titan, water marks on Enceladus, previously unknown rings that could not be seen with ground-based instruments were detected.

Saturn's rings in the form of appendages on the sides can be seen even with small binoculars with a lens diameter of 15 mm or more. Through a telescope with a diameter of 60-70 mm, one can already see a small disk of the planet without details, surrounded by rings. The larger instruments (100-150 mm) show Saturn's cloud belts, pole caps, the shadow of the rings and some other details. With telescopes larger than 200 mm, you can perfectly see dark and light spots on the surface, belts, zones, details of the structure of the rings.