When was the planet Saturn discovered? Saturn - The Lord of the Rings. He was seen by ancient people

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 calling 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 varies 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 supplier of scientific data and discoveries for many years now. For children, the planet Saturn, as in principle 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 the size of Saturn and 3.34 times its mass.

In fact, Saturn is very large, but light. 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 a factor of 9.4 and in mass by a factor of 95. The volume of a gas giant could fit 763 planets like 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 the 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 the north. During the Saturnian year (almost 30 Earth years), there come periods when the planet is seen edge-on from the Earth and the plane of the giant's rings coincides with our angle of view, and they disappear from view. The thing is that the rings are extremely thin, so from a great distance it is almost impossible to see them from the edge. The next time the rings will disappear for the Earth observer in 2024-2025. Since Saturn's year is almost 30 years long, since Galileo first observed it through a telescope in 1610, it has circled the Sun about 13 times.

Climatic features

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

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

The seasons influence the planet's weather. 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, and currently only about 1,000 km/h (measured in 2003).

Saturn completes one revolution around its axis in 10.656 hours. It took scientists a lot of time and research to find such an accurate figure. Since the planet has no surface, it is not possible to observe the passage of the same areas of the planet, thus estimating its rotation speed. Scientists used the planet's radio emissions to estimate the rate 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

The equatorial diameter is 120,536 km, 9.44 times that of the Earth;

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

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

Volume - 8.2713 x 10 * 14 km3, 763.6 times larger 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 moons, in fact about 40% of the moons 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 that over time the device will find even more icy satellites.

Despite the fact that Saturn is too hostile for any form of life that we know that its moon 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 Saturn's tidal action) that creates enough heat for liquid water to exist. Some scientists believe that there is a chance of life on Enceladus.

Planet formation

Like the rest of the planets, Saturn formed from the 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 a supernova shock wave. This event initiated the beginning of the contraction 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 cold enough and, in fact, remained untouched.

The material from the solar nebula formed more and more planetesimals. These planetesimals collided together, merging into planets. At some point in Saturn's early history, its moon, about 300 km across, was torn apart by its gravity and created the 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 could 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 sink towards the core. The friction of these droplets heated up the planet, and now it emits about 2.3 times more energy than it receives from the Sun.

Ring formation

View of the planet from space

The main distinguishing feature of Saturn is the rings. How are the rings formed? There are several versions. The conventional theory is that the rings are nearly as old as the planet itself and have been around for at least 4 billion years. In the giant's early history, a 300 km satellite got too close to it and was torn to pieces. There is also the possibility that two satellites collided together, or a large enough comet or asteroid hit the satellite, and it simply fell apart right in orbit.

Alternative hypothesis for ring formation

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

But here's the problem: the ice in the rings is too clean. If the rings formed with Saturn, billions of years ago, then we would expect them to be completely covered in dirt from micrometeor impacts. 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 together and colliding with each other, making it difficult to determine their age. This is one of the mysteries yet to be solved.

Atmosphere

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

Atmospheric features

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

Winds in the atmosphere

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

Clouds in 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 consist of water and are located about 130 km below the tropopause. The temperature here is 0 degrees.

The lower, the more the pressure and temperature increase and the gaseous hydrogen slowly turns into a liquid.

Hexagon

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

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 by 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 the Earth.

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

Reason for the formation of a hexagon

So why is the North Pole vortex shaped like a hexagon? Astronomers find it difficult to answer this question 100%, but one of the experts and team members in charge of the Cassini visual and infrared spectrometer said: “This is a very strange storm that has 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 is the 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 also storms on Saturn, although they are not so big and intense, but compared to the Earth 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 occur once a year on Saturn (once every 30 Earth years).

atmosphere and surface

The planet is very reminiscent of a ball, made almost entirely of hydrogen and helium. Its density and temperature change as you move deeper into the planet.

Composition of the atmosphere

The planet's outer atmosphere consists 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 pictures.

Nucleus

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 other planets in order to have time to acquire primary gases.

The gas giant most likely formed from rocky or icy components, and the low density indicates liquid metal and rock impurities 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 of thick syrup with impurities of stone fragments.

metallic hydrogen

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. Titan contributes to the appearance of ionized particles in the planet's magnetosphere, which create auroras in the atmosphere. Voyager 2 detected high solar wind pressure on the planet's magnetosphere. According to measurements made during the same mission, the magnetic field only extends over 1.1 million km.

Planet size

The planet has an equatorial diameter of 120,536 km, 9.44 times that of Earth. The radius is 60268 km, which makes it the second largest planet in our solar system, second only to Jupiter. It, like all other planets, is an oblate spheroid. This means that its equatorial diameter is larger than the diameter measured through the poles. In the case of Saturn, this distance is quite significant, due to the high speed of the planet's rotation. The polar diameter is 108728 km, which is 9.796% less than the equatorial diameter, so the shape of Saturn is oval.

Around Saturn

Day length

The rotational speed of the atmosphere and the planet itself can be measured by three different methods. The first one is measuring the speed of the planet's rotation 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 areas 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 the day is based on the measurement of radio emission. This method gives a planetary rotation speed of 10 hours 39 minutes and 22.4 seconds. Despite these figures, the rate of rotation of the interior of the planet at present cannot be accurately measured.

Again, the equatorial diameter of the planet is 120,536 km, and the polar one is 108,728 km. It is important to know why this difference in these numbers affects the planet's rotation rate. The same situation is 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 period of rotation. 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 emission 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 spacecraft Ulysses also took measurements 15 years later, and gave a result of 10 hours 45 minutes 45 seconds, with a 36 second error.

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

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

New data

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

Cassini's basic characteristics of the planet suggest that the solar wind is the most likely cause of the difference in the data. Differences in measurements of the rotation of the magnetic field occur every 25 days, which corresponds to the rotation period of the Sun. The speed of the solar wind is also constantly changing, which must 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 some conditional boundary 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 the 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 gravity at any point on its imaginary surface would be 91% of that on Earth. In other words, if your scale shows you weigh 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, gravity is 2.5 times greater than Earth's. On Mars, only 1/3, and on the Moon 1/6.

What makes the force of gravity so weak? The giant planet mainly consists of hydrogen and helium, which he 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. All due to the fact that the planet has an extremely low density.

planet temperature

Voyager 2 image

The uppermost layer of the atmosphere, which is located on the border with space, has a temperature of -150 C. But, as you dive into the atmosphere, the pressure rises and, accordingly, the temperature rises. At the core of the planet, the temperature can reach 11,700 C. But where does such a high temperature come from? 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 made up 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 looking through a small telescope, the color of the planet is visible as a pale yellow with hints of orange. With more powerful telescopes such as the Hubble or NASA's Cassini spacecraft, you can see thin layers of clouds and storms that are a mixture of white and orange. But what gives Saturn its color?

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

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

Saturn has a striped atmosphere similar to that of Jupiter, but the stripes are much weaker and wider near the equator. It also doesn't have long-lived storms—nothing like the Great Red Spot—that often occur when Jupiter approaches the northern hemisphere's summer solstice.

Some of the photos provided by Cassini appear blue, similar to Uranus. But that's probably because we're seeing light scattering from Cassini's point of view.

Compound

Saturn in the night sky

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 was made of. Through various methods, scientists have learned that Saturn's chemical composition is 96% hydrogen, 3% helium, and 1% various elements that 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. Beneath the clouds, atmospheric pressure increases, which causes an increase in temperature and the hydrogen turns into a liquid state. As we move deeper into the planet, pressure and temperature continue to increase. As a result, in the nucleus, hydrogen becomes metallic, passing into this special state of aggregation. The planet is believed to have a loose core, which, in addition to hydrogen, consists of rocks 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 the F ring. Voyager 1 flew by the following year, sending surface details of some of the satellites back 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 gaps that Voyager 1 first saw.

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

Radiation

When NASA's Cassini lander first arrived at 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 139,000 km from the center of Saturn and extends up to 362,000 km.

Northern Lights on Saturn

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

Due to the presence of a magnetic field, the 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 the 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 as seen by the Hubble telescope

Aurora Gallery

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 655,000,000 km apart.

When they are located on opposite sides of each other, the planets Saturn and 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 escape velocity: 35.5 km/s

Free fall acceleration: 10.44 m/s2

Natural satellites: 62

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

Orbital period: 10,759.22 days

Perihelion: 1.35255 billion km

Aphelion: 1.5145 billion km

Orbital speed: 9.69 km/s

Orbital inclination: 2.485 degrees

Orbit eccentricity: 0.0565

Sidereal rotation period: 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 brilliance (maximum): 0.43 magnitudes

Story

Space image taken by the Hubble telescope

The planet is clearly visible to the naked eye, so it's hard to say 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 built his primitive but working telescope and looked at the planet in 1610. Of course, Galileo didn't understand what he was seeing and thought the rings were large moons on either side of the planet. That was before Christian Huygens used the best telescope to see that they weren't really moons, but rings. Huygens was also the first to discover the largest moon, Titan. Despite the fact that the visibility of the planet 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 named 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 flight of spacecraft 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 was the first spacecraft to visit Saturn, passing within 20,000 km of 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 lander arrived in the Saturn system, and compiled the most detailed description of the planet Saturn and its system from observations. Cassini has made nearly 100 flybys of Titan's moon, several flybys of many other moons, and 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 made up 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?

Rings: view from Cassini

Let's 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, separated by the Cassini gap, followed by the C ring. After the 3 main rings, there are smaller, dusty rings: D, G, E, and the F ring, which is the . So how many main rings? That's right - 8!

These three main rings and 5 dust rings make up the bulk. But there are several more rings, such as Janus, Meton, Pallene, as well as the arcs of the Anf ring.

There are also smaller rings, and gaps in various rings that are difficult to count (for example, the Encke gap, the Huygens gap, the 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 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 satellites) two years earlier and was instantly fascinated by them.

Ring parameters

The planet is sometimes referred to as the "Pearl of the Solar System" because its ring system looks like a crown. These rings are made up of dust, stone, and ice. That is why the rings do not break up, because. it is not whole, 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 tall buildings, reaching a kilometer across. What are rings made of? Mostly ice particles, although there are also dust rings. The striking thing is that each ring rotates at a different speed with respect 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. The rings of Saturn stand out because they are the largest and brightest. The rings are about one kilometer thick and span up to 482,000 km from the center of the planet.

Saturn's rings are named in alphabetical order according to the order in which they were discovered. This makes the rings a bit confusing, listing them out of order from the planet. Below is a list of the main rings and the gaps between them, as well as the distance from the center of the planet and their width.

The sounds of the rings

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

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

The emergence of rings

How did the rings appear? 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 have most likely been captured 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 suggest that all the material in the rings is the product of satellite collisions with asteroids or comets. After the collision, the remnants of the asteroids were able to escape the gravitational pull of the planet 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.

Gallery of pictures of rings

Life on Saturn

It is hard to imagine a less hospitable planet for life than Saturn. The planet is composed almost entirely of hydrogen and helium, with trace amounts of water ice in the lower cloud layer. 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 to keep the water from freezing, then the pressure of the atmosphere at this level is the same as a few kilometers below the Earth's ocean.

Life on the satellites of the planet

To find life, scientists offer to look at the planet's satellites. They are made up of a significant amount of water ice, and their gravitational interaction with Saturn likely keeps their interiors warm. The moon 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 thought to be a place with the potential to 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 “broth”.

position in the sky

Saturn and its six moons, amateur photo

Saturn is visible in the sky as a fairly bright star. The current coordinates of the planet are best specified in specialized planetarium programs, such as Stellarium, and events related to its coverage or passage over a particular region, as well as everything about the planet Saturn, can be peeped 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.

Upcoming confrontations

Knowing the ephemerides of the planet and its magnitude, finding Saturn in the starry sky is not difficult. However, if you have little experience, then the search for it can be delayed, so we recommend using amateur telescopes with a Go-To mount. Use a telescope with a Go-To mount and you won't need to know the coordinates of the planet and where it can be seen right now.

Flight to the planet

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

For example: It took Pioneer 11 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 took six years and nine months! The New Horizons spacecraft used Saturn as a gravitational springboard on its way to Pluto and arrived two years and four months after launch. Why such a huge difference in flight times?

The first factor determining flight time

Let's consider whether the spacecraft is launched directly to Saturn, or does it use other celestial bodies along the way as a slingshot?

The second factor determining flight time

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

With these factors in mind, let's look at the missions mentioned above. Pioneer 11 and Cassini used the gravitational influence of other planets before heading towards Saturn. These flybys of other bodies added years to an already long trip. Voyager 1 and 2 used only Jupiter on their way to Saturn and arrived much faster. The New Horizons ship had several distinct advantages over all other probes. The 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 image of Saturn taken on July 19, 2013 by the Cassini spacecraft. In the discharged ring on the left, the white dot is Enceladus. The ground 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 flew by Jupiter and used the planet's gravity to change its trajectory and head towards Saturn. He arrived on September 1, 1979, passing 22,000 km above the planet's cloud layer. 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. He 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 its twin brother Voyager 2 to other giant planets. As a result, it turned out that although the apparatus transmitted a lot of scientific information, it did not see the surface of Titan, since it is opaque to visible light. Therefore, in fact, the ship was sacrificed in favor of the largest satellite, on which scientists had high hopes, but 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 carried out an almost identical program. It reached the planet on August 26, 1981. In addition to orbiting 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 a gravitational acceleration from the planet, headed towards Uranus (successful flyby in 1986) and Neptune (successful flyby in 1989), after which it continued its journey to the borders of the solar system.

Cassini-Huygens

Views of Saturn from Cassini

NASA's Cassini-Huygens probe, which arrived at the planet in 2004, was able to truly study the planet from a permanent 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 system of Saturn and its moons for many years now. Among his discoveries, it is worth noting 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 end the Cassini mission in 2017 due to cuts in NASA's budget for planetary exploration.

Future missions

The next Titan Saturn System Mission (TSSM) should not be expected until 2020, but rather much later. Using gravitational maneuvers near the Earth and Venus, this device will be able to reach Saturn approximately in 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 landing module will be involved, and 20 months for studying the satellite from orbit. Russia may also take part in this truly grandiose project. The future involvement of the federal agency Roscosmos is already under discussion. While this mission is far from being realized, we still have the opportunity to enjoy the fantastic images of Cassini, which he transmits regularly and which everyone has access to just a few days after their transmission to Earth. Good luck exploring Saturn!

Answers to the most common questions

1. Who was the planet Saturn named after? 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 was the first to determine 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 maps and specialized software, such as Stellarium.
5. What are the coordinates of the site? Since this is a planet, its coordinates change, you can find out the ephemerides of Saturn on specialized astronomical resources.

Planet characteristics:

• Distance from the Sun: 1,427 million km
• Planet Diameter: ~ 120,000 km*
• Days on the planet: 10h 13m 23s**
• Year on the planet: 29.46 years old***
• t° on the surface: -180°C
• Atmosphere: 96% hydrogen; 3% helium; 0.4% methane and traces of other elements
• Satellites: 18

* diameter at the equator of the planet
** period of rotation around its own axis (in Earth days)
*** orbital period around the Sun (in Earth days)

Saturn is the sixth planet from the Sun - the average distance to the star is almost 9.6 AU. e. (≈780 million km).

Presentation: the planet Saturn

The period of revolution of the planet in orbit is 29.46 years, and the time of revolution around its axis is almost 10 hours and 40 minutes. The equatorial radius of Saturn is 60268 km, and its mass is more than 568 thousand billion megatons (with an average density of planetary matter of ≈0.69 g/cm3). Thus, Saturn is the second largest and most massive planet in the solar system after Jupiter. At an atmospheric pressure of 1 bar, the temperature of the atmosphere is 134 K.

Internal structure

The main chemical elements that make up Saturn are hydrogen and helium. These gases pass at high pressure inside the planet, first into a liquid state, and then (at a depth of 30 thousand km) into a solid state, since under the physical conditions existing there (pressure ≈3 million atm.), hydrogen acquires a metallic structure. A strong magnetic field is created in this metal structure, its strength at the upper boundary of the clouds in the equator region is 0.2 Gs. Below the layer of metallic hydrogen is a solid core of heavier elements, such as iron.

atmosphere and surface

In addition to hydrogen and helium, the planet's atmosphere contains small amounts of methane, ethane, acetylene, ammonia, phosphine, arsine, german and other substances. The average molecular weight is 2.135 g/mol. The main characteristic of the atmosphere is its uniformity, which does not make it possible to distinguish fine details on the surface. The speed of the winds on Saturn is high - at the equator it reaches 480 m/s. The temperature of the upper boundary of the atmosphere is 85 K (-188°C). There are many methane clouds in the upper atmosphere - several dozen belts and a number of individual eddies. In addition, powerful thunderstorms and auroras are quite often observed here.

Satellites of the planet Saturn

Saturn is a unique planet that has a ring system with billions of small objects of ice particles, iron and rock, as well as many satellites - all of which revolve around the planet. Some satellites are large. For example, Titan, one of the largest satellites of the planets in the solar system, is second in size only to Jupiter's moon Ganymede. Titan is the only satellite in the entire solar system that has an atmosphere, moreover, similar to the earth, where the pressure is only one and a half times higher than at the surface of the planet Earth. In total, Saturn has 62 satellites already discovered, they have their own orbits around the planet, the rest of the particles and small asteroids are included in the so-called ring system. All new satellites are starting to open up to researchers, so for 2013 the last confirmed satellites were Egeon and S / 2009 S 1.

The main feature of Saturn, which distinguishes it from other planets, is a huge system of rings - its width is almost 115 thousand km with a thickness of about 5 km. The constituent elements of these formations are particles (their size reaches several tens of meters), consisting of ice, iron oxide and rocks. In addition to the ring system, this planet has a large number of natural satellites - about 60. The largest is Titan (this satellite is the second largest in the solar system), whose radius exceeds 2.5 thousand km.

With the help of the interplanetary apparatus Cassini, a unique phenomenon was captured on the planet thunderstorm. It turns out that on Saturn, as well as on our planet Earth, thunderstorms occur, only they occur many times less often, but the duration of a thunderstorm lasts for several months. This video thunderstorm lasted on Saturn from January to October in 2009 and was the most real storm on the planet. Radio frequency crackles (characterizing lightning flashes) are also heard on the video, as Georg Fischer (scientist at the Space Research Institute in Austria) said about this extraordinary phenomenon - "This is the first time we've seen lightning and heard radio data at the same time"

Exploring the planet

Galileo was the first to observe Saturn in 1610 with his 20x telescope. The ring was discovered by Huygens in 1658. The greatest contribution to the study of this planet was made by Cassini, who discovered several satellites and gaps in the structure of the ring, the widest of which bears his name. With the development of astronautics, the study of Saturn was continued using automatic spacecraft, the first of which was Pioneer-11 (the expedition took place in 1979). Space research was continued by vehicles from the Voyager and Cassini-Huygens series.

> > > Who discovered Saturn

Who found Saturn- the sixth planet of the solar system: observations in the sky, the study of Galileo and Huygens, the discovery of rings and satellites, the launch of vehicles.

Saturn is one of the five planets in the solar system that can be found with the naked eye without using a telescope. But for a simple observer, a particular celestial body will seem like a familiar bright star, which was observed by the ancients. So it is difficult to name a person who is responsible for the very fact of the discovery. That is, we will never know who first found Saturn in the sky. But the planet got its name from the Romans in honor of the god of the harvest.

The first telescope observation was made by Galileo Galilei in 1610. But his device was imperfect, so the protrusions found seemed somewhat incomprehensible. Moreover, after a few years, he again looked at the planet, and there were no formations nearby.

In 1659, Christian Huygens looked at Saturn. His telescope was much better, so he realized that he was seeing not only the planet, but also a large system of rings. Also noticed the satellite Titan.

Giovanni Cassini saw Saturn's moons Iapetus, Rhea, Tethys and Dione. More information came from space missions. The first photos of Saturn arrived with Pioneer 11 in 1979. He swept at a distance of 21,000 km. The rest of the data came from Voyagers and the main mission, Cassini, in 2006.

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 about 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 the solar one: the main elements are hydrogen and helium, as well as numerous impurities of ammonia, methane, ethane, acetylene and water. In terms of internal composition, it is more reminiscent of Jupiter: a core of iron, water and nickel, covered with a thin shell of metallic hydrogen. The atmosphere of a huge amount of gaseous helium and hydrogen envelops the core in a thick layer. Because the planet is made up mostly of gas and there is no solid surface, Saturn is considered a gas giant. 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 degree of compression of Saturn, on the contrary, is the highest. This means that its equatorial and polar radii are very different in size - 60,300 km and 54,400 km, respectively. This also implies a large difference in speeds for different parts of the atmosphere depending on latitude. The average speed of rotation around the axis is 9.87 km/s, and the orbital speed is 9.69 km/s.

A majestic spectacle is the system of Saturn's rings. 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 B ring, the brightest and widest, is separated from the A ring by a space called the Cassini gap, in which the thinnest and almost transparent rings are located. It is little known that all four giant planets actually have rings, but they are almost invisible in all but Saturn.

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

Planet formation

There are two hypotheses for the origin of Saturn:

The first, the contraction hypothesis, states that the sun and the planets 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 sections 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 one is the formation of dense bodies in the gas and 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 composition between these planets and the Sun. At the second stage, larger bodies attracted gas from the cloud surrounding them.

Internal structure

The inner region of Saturn is divided into three layers. In the center there is a small but massive core of silicates, metals and ice compared to the total volume. Its radius is about a quarter of the radius of the planet, and its mass is from 9 to 22 Earth masses. The temperature in the core 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 contraction of Saturn: when the planet was formed from a protoplanetary disk, the gravitational energy of dust and gas turned into kinetic and then into heat. Secondly, part of the heat is created due to the Kelvin-Helmholtz mechanism: when the temperature drops, the pressure also drops, due to which the substance of the planet is compressed, and potential energy is converted into heat. Third, as a result of the 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 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 determine exactly where the atmosphere begins. For Saturn, the height at which methane boils is taken as such a zero level. The main components of the atmosphere are hydrogen (96.3%) and helium (3.25%). Also, spectroscopic studies 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 of the clouds are composed of ice crystals and water droplets.

The gases in the atmosphere are constantly moving, as a result of which they take the form of bands parallel to the diameter of the planet. There are similar bands on Jupiter, but they are much fainter on Saturn. Due to convection and rapid rotation, incredibly strong winds are formed, the most powerful in the solar system. Winds mostly 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. As we move away from the equator, the winds weaken, 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, the Great White Oval appears on Saturn - a super-powerful hurricane, the size of which each time becomes larger. During the 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 form has been stable for 20 years after the first observation. Each side of it 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.

The Voyager and Cassini cameras captured glowing regions on Saturn. They were the aurora borealis. They are located at a latitude of 70-80° and look like very bright oval (rarely spiral) rings. It is believed that the 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 discharges are observed during strong storms.

Rings

When we talk about Saturn, the first thing that comes to mind is its amazing rings. Spacecraft observations have shown that all gaseous planets have rings, but only on Saturn they are clearly visible and pronounced. The rings are made up of tiny particles of ice, rocks, dust, fragments of meteorites drawn in by the gravity of the system from outer space. They are more reflective than the disk of Saturn itself. The ring system consists of three main rings and a thinner fourth. Their diameter is approximately 250,000 km, and their thickness is less than 1 km. The rings are named by the letters of the Latin alphabet in order, from the periphery to the center. Rings A and B are separated from each other by a space 4000 km wide, called the Cassini gap. Inside the outer ring A there is also a gap - Encke's dividing strip. Ring B is the brightest and widest, and Ring C is almost transparent. The D, E, F, G rings, which are dimmer and closest to the outer part of Saturn's atmosphere, 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 “capture” by the planet of some of its satellites. They were destroyed, and their fragments were evenly distributed along the orbit. The second says that the rings formed along with the planet itself from the initial cloud of dust and gas. The particles that make up the rings cannot form larger objects like satellites due to their too small size, random 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 substance is lost, being absorbed by the planet or dissipating into the circumplanetary space, and part, on the contrary, is compensated when comets and asteroids interact with the gravitational field.

Of all the gas giants, Saturn has the most similarities with Jupiter in its 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 the solar one. 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 fluxes. So Saturn could have become a second star, but it didn't have enough material to generate enough gravitational force to fuel fusion.

Modern space observations have shown that the 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.

The Voyager spacecraft have detected strong winds on Saturn. Air flow speeds reach 500 m/s. The winds blow mainly in an easterly direction, although as they move away from the equator, their strength weakens and streams directed to the west appear. Some data suggest that the circulation of gases occurs not only in the upper layers of the atmosphere, but also at depth. Also, hurricanes of colossal power periodically appear in the atmosphere of Saturn. The largest of them - 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 goal is to study the rings, atmosphere and magnetic field of Saturn and its moons. Thanks to Cassini, many high-quality images have been obtained, auroras have been discovered, the hexagon mentioned above, mountains and islands on Titan, traces of water on Enceladus, previously unknown rings that could not be seen with ground-based instruments.

The rings of Saturn in the form of processes on the sides can be seen even in small binoculars with a lens diameter of 15 mm or more. A telescope with a diameter of 60-70 mm already shows a small disk of the planet without details, surrounded by rings. Larger instruments (100-150 mm) show Saturn's cloud belts, pole caps, ring shadows, 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.

Saturn is one of the five planets in the solar system that are easily visible to the naked eye from Earth. At its maximum, the brightness of Saturn exceeds the first magnitude.

Observing Saturn for the first time through a telescope in 1609-1610, Galileo Galilei noticed that Saturn does not look like a single celestial body, but like three bodies that almost touch each other, and suggested that these are two large "companions" (satellites) of Saturn . Two years later, Galileo repeated his observations and, to his amazement, found no satellites.

In 1659, Huygens, using a more powerful telescope, found out that the "companions" are actually a thin flat ring encircling the planet and not touching it. Huygens also discovered Saturn's largest moon, Titan. Since 1675, Cassini has been studying the planet. He noticed that the ring consists of two rings separated by a clearly visible gap - the Cassini gap, and discovered several more large satellites of Saturn.

In 1979, the Pioneer 11 spacecraft first flew near Saturn, followed by Voyager 1 and Voyager 2 in 1980 and 1981. These devices were the first to detect the magnetic field of Saturn and explore its magnetosphere, observe storms in the atmosphere of Saturn, take detailed pictures of the structure of the rings and find out their composition.

In the 1990s, Saturn, its moons and rings were repeatedly studied by the Hubble Space Telescope. Long-term observations have provided a lot of new information that was not available to Pioneer 11 and Voyagers during their single flyby of the planet.

In 1997, the Cassini-Huygens spacecraft was launched to Saturn and, after seven years of flight, on July 1, 2004, it reached the Saturn system and went into orbit around the planet. The main objectives of this mission, designed for at least 4 years, is to study the structure and dynamics of the rings and satellites, as well as to study the dynamics of the atmosphere and magnetosphere of Saturn. In addition, a special probe "Huygens" separated from the apparatus and parachuted down to the surface of Saturn's moon Titan.