The moon Io is the most active and most mysterious object in the solar system. Io is a unique satellite of Jupiter on which volcanoes erupt. Trajectory of motion of the satellite of Jupiter Io

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And about- the most volcanically active satellite in the Solar System of the Galileo group: table of parameters, detection, name, research with photos, composition and surface.

Io is the most volcanically active moon of Jupiter in the solar system.

The deeper we move into the system, the more secrets we uncover. The most interesting were the 4 largest satellites of Jupiter, called the Galilean moons. Io attracts attention due to its volcanic activity (more than 400 active volcanoes).

Discovery and name of Io's satellite

In 1610, Galileo Galilei noticed the satellite using an updated telescope of his own invention. But he could not distinguish it from Europa, so he perceived it as a single point of light. But the next day I saw individual bodies.

In 1614, Simon Marius claimed to have spotted the moons on his own. It is interesting that it was his names that were adopted as official designations, because previously they were simply listed in Roman numerals.

Io was the lover of Zeus. She came from a line of descendants of Hercules and served as a priestess in the temple of Hera. All of its formations were named after deities associated with fire and thunder, as well as characters and locations from Dante's work.

There are now 225 volcanoes, plateaus, mountains and large albedoes recorded in the IAU. You can meet Prometheus, Tvashtar Patera or Pan Mensa.

Size, mass and orbit of the moon Io

With a radius of 1821.6 km and a mass of 8.93 x 10 22 kg, it reaches only 0.266 times the size of Earth and 0.015 times the massiveness. The average distance from the planet is 421,700 km, but due to the eccentricity of 0.0041 it can approach at 420,000 km and move away at 432,400 km.

It is the most inland satellite of the Galilean group, and its orbital path runs between Thebes and Europa. It resides in a tidal block and always faces Jupiter with one side. Volcanic activity on Io is a unique phenomenon that remains to be studied.

It takes 42.5 hours to complete the orbital path at a resonance of 2:1 with Europa and 4:1 with Ganymede. These indicators influenced the eccentricity, which became the initial source for heating and geological activity.

Composition and surface of the moon Io

With a density of 3.528 g/cm3, Io bypasses any moon in the system. The object is represented by silicate rock and iron. In terms of content, they are closer to terrestrial planets. The crust and mantle are rich in silicates, and the core is made of iron and iron sulfide. The latter covers 20% of the satellite's mass, and in a radius extends to 350-650 km. But this is the case if it also contains iron. When adding sulfur, the coverage within the radius will increase to 550-900 km.

The mantle is made up of 75% magnesium and high levels of iron. The lithosphere of basalt and sulfur occupies 12-40 km.

Analysis of magnetic and heat flows showed that the magma ocean is located at a depth of 50 km, occupies the same thickness and 10% of the mantle. The temperature mark is delayed at 1200°C.

The main source of heating is the tidal bend created by orbital resonance with Europa and Ganymede. Heating is also affected by the moon's distance from the planet, eccentricity, composition and physical state.

The tidal block causes friction, which increases the temperature inside Io. This causes volcanic activity and lava emissions to a height of 500 km. The surface layer is almost completely devoid of craters and is covered with plains, mountains, pits and volcanic flows. The bright appearance also hints at this.

There is always sulfur dioxide on the surface, creating large old and gray areas. Atomic sulfur forms yellow and yellow-green areas. Sulfur in polar regions is exposed to radiation, causing it to turn red.

There is practically no water on the moon, although ice deposits remain in some areas. The mountains stretch on average 6 km, and the maximum height reaches 17.5 km on the southern side. They are isolated and have no visible global tectonic patterns.

Most mountains are created due to compression in the lithosphere, which is caused by deep shifts.

The mountains are made in various shapes and are represented by plateaus and sloping blocks. Those associated with volcanoes resemble shield volcanoes with sharp slopes. They are usually smaller in size than the others (1-2 km in height and 40-60 km in width).

Active volcanoes on the moon Io

Here is the first volcanically active object in the system. Its surface is covered with hundreds of volcanoes and lava flows. This not only creates lava emissions 500 km high, but also affects the geology.

For example, large-scale eruptions lead to flows of hundreds of kilometers, represented by basaltic silicates, iron and magnesium. Sulfur, sulfur dioxide and ash are released into the space.

Volcanic activity also creates numerous depressions extending for 41 km or more.

The atmosphere of the moon Io

The weak layer of the atmosphere consists of sulfur dioxide, sulfur monoxide, atomic sulfur, sodium chloride and oxygen. The pressure ranges from 3.3 x 10 -5 to 3 x 10 -4 Pa. On the night side it can fall to 0.1 x 10 -7 Pa.

The temperature also ranges from -163.15°C to -183.15°C, but the maximum rises to 1526.85°C. Atmospheric density levels are highest in volcanic ridges, causing replenishment of the atmosphere. Volcanic plumes act as a source for sulfur dioxide. 104 kg are released per second, but most of it condenses towards the surface.

Elements like NaCl, SO, S and O come from volcanic degassing. Auroras are formed due to the contact of charged particles of Jupiter's magnetosphere with the atmosphere of the satellite. The most striking events are observed near the equatorial line.

Contact with the magnetosphere of Jupiter's satellite Io

Io influences the creation of the planetary magnetosphere. Jupiter rips material out of the lunar atmosphere at a speed of 1 ton per second. Most end up in orbit around the planet, forming a neutral cloud where oxygen, sulfur, sodium and potassium are present.

Planetary magnetic field lines crossing the moon combine Io's atmosphere and neutral cloud with Jupiter's polar atmospheric layer. Because of this, a current is formed, which creates aurora.

Lines passing by the lunar ionosphere also result in an electrical current capable of generating up to 400,000 volts. An induced magnetic field arises from the current. Similar things were found in other Galilean satellites.

Exploring the moon Io

For the first time, Pioneer 10 (1973) and Pioneer 11 (1974) flew past the satellite. The missions made it possible for the first time to assess the massiveness, composition, high level of density, the presence of an atmosphere and intense radiation belts.

In 1979, Voyagers 1 and 2 flew by, with their help it was possible to obtain better images. They demonstrated a colored landscape for the first time. Information also showed that there is a lot of sulfur on the surface and active volcanoes.

In 1995, the Galileo spacecraft arrived at Jupiter, performing a close approach on December 7. Galileo tracked the eruption process, understood the composition, and determined surface changes since the Voyagers arrived.

The mission was expanded twice in 1997 and 2000. During this time, Galileo flew past Io 6 times, which made it possible to clearly determine geological processes and exclude the magnetic field.

In 2000, Cassini moved closer and further away from the Jupiter system, allowing for a joint survey. This led to the discovery of a new trail and a better understanding of the auroras.

In 2007, New Horizons flew past the system, producing many images of the surface, plumes, and new sources of the jets.

In 2011, the Juno spacecraft was launched, which now monitors the planet and its satellites. Volcanic activity can be observed using an infrared spectrometer. In 2022, the JUICE mission may be launched, which will be able to examine volcanoes in 2 years until it is installed in the orbit of Ganymede.

The IVO mission was planned to be launched in 2021, but was not approved. Io is considered one of the most interesting moons and the densest in the system. Despite the many volcanoes, it is extremely frosty in places and overflowing with electricity. Perhaps in the future we will be able to use the induced magnetic field for our own purposes. But the volcanoes will not let the colonists get close. Below is a map of Jupiter's moon Io.

This way you found out which planet Io is a satellite of.

Click on the image to enlarge it

Orbit = 422,000 km from Jupiter
Diameter = 3630 km
Weight = 8.93*1022 kg

Io is the third largest and closest satellite of Jupiter. Io is slightly larger than the Moon, a satellite of the Earth. Io was the first lover of Zeus (Jupiter), whom he turned into a cow to try to hide from the jealous Hera. Io was discovered by Galileo and Marius in 1610.

Unlike most moons in the outer solar system, Io and Europa are similar in composition to the terrestrial planets, primarily in the presence of silicate rocks. Recent data from the Galileo satellite indicate that Io has an iron core (possibly a mixture of iron and iron sulfide) with a radius of at least 900 km.

Io's surface is radically different from the surface of any other body in the solar system. This was a completely unexpected discovery made by scientists using the Voyager spacecraft. They expected to see a surface covered with craters, like other bodies with a solid surface, and estimate the age of Io's surface from them. But very few craters have been found on Io, which means its surface is very young.

Instead of craters, Voyager 1 found hundreds of volcanoes. Some of them are active! Photographs of eruptions with torches 300 km high were transmitted to Earth by the Voyager and Galileo spacecraft. This was the first real evidence that the nuclei of other terrestrial bodies are also hot and active. The material erupting from Io's volcanoes is some form of sulfur or sulfur dioxide. Volcanic eruptions change quickly. In just the four months between the flights of Voyager 1 and Voyager 2, some of the volcanoes ceased activity, but others appeared.

Recent images from NASA's Infrared Camera Telescope at Mauna Kea in Hawaii show a new and very large eruption. The Galileo images also show many changes since Voyager's flight. These observations confirm that Io's surface is indeed very active.

Io's landscapes are amazingly varied: pits up to several kilometers deep, lakes of molten sulfur (below right), mountains that are not volcanoes, flows of some kind of viscous liquid (some kind of sulfur?) stretching for hundreds of kilometers, and volcanic vents. Sulfur and sulfur-containing mixtures produce the wide range of colors seen in images of Io.

Analysis of images taken by Voyager led scientists to theorize that lava flows on the surface of Io consist mainly of molten sulfur with various impurities. However, consistent ground-based infrared studies indicate that they are too hot to be liquid sulfur. One idea for this is that the lava on Io is molten silicate rock. Recent observations indicate that this substance may contain sodium.

Some of the hottest spots on Io reach temperatures of 1500 K, although the average temperature is much lower, around 130 K.

Io probably gets its energy for all this activity from tidal interactions with Europa, Ganymede, and Jupiter. Although Io, like the Moon, is always turned with the same side towards Jupiter, the influence of Europa and Ganymede still causes slight fluctuations. These vibrations stretch and bend Io's surface by as much as 100 meters and generate heat, causing the surface to heat up.

Io crosses Jupiter's magnetic field lines, generating an electric current. Although small compared to tidal heating, this current can carry more than 1 trillion watts. Recent data from Galileo indicates that Io may have its own magnetic field, like Ganymede. Io has a very thin atmosphere consisting of sulfur dioxide and possibly some other gases. Unlike Jupiter's other moons, Io has very little or no water.

The volcanoes on Io are very hot and contain unfamiliar ingredients, according to the latest data from the Galileo spacecraft. Galileo's near-infrared spectrometer has detected extremely high temperatures inside volcanoes. They turned out to be much higher than previously thought. The spectrometer is capable of detecting the heat of a volcano and indicating the location of various materials on Io's surface.

Inside the Pele volcano, named after the mythological Polynesian goddess of fire, the temperature is much higher than the temperature inside any volcano on Earth - it is about 1500 ° C. It is possible that billions of years ago volcanoes on Earth were just as hot. Now scientists are interested in the following question: do all volcanoes on Io erupt such hot lava, or are most volcanoes similar to basaltic volcanoes on Earth, which emit lava at lower temperatures - about 1200 ° C?

Even before Galileo flew close to Io in late 1999 and early 2000, Io was known to have two large volcanoes with very high temperatures. Now Galileo has discovered that there are more high-temperature regions on Io than distant observations have shown. This meant that Io could have much smaller volcanoes with very hot lava.

One of the most active volcanoes on Io is Prometheus Volcano. Its emissions of gas and dust were recorded earlier by the Voyager spacecraft, and now by Galileo. The volcano is surrounded by a ring of bright sulfur dioxide.

As already mentioned, the spectrometer on board Galileo can recognize different substances by determining their ability to absorb or reflect light. Thus, hitherto unknown material was discovered. According to scientists, it could be an iron-containing mineral, such as pyrite, present in silicate lava. But further research showed that, most likely, this substance does not rise to the surface along with lava, but rather is ejected by volcanic torches. It is possible that identifying this mysterious composition will require laboratory experiments using spacecraft observations.

Io has a solid metallic core surrounded by a rocky mantle, like Earth's. But under the influence of the Moon's gravity, the shape of the Earth is slightly distorted. But the shape of Io under the influence of Jupiter is distorted much more. In fact, Io is permanently oval shaped due to Jupiter's rotation and tidal influence. Galileo measured Io's polar gravity when it flew by in May 1999. Given a known gravitational field, Io's internal structure can be determined. The relationship between polar and equatorial gravity shows that Io has a large metallic core, mostly iron. The Earth's metallic core generates a magnetic field. It is not yet known whether Io's metallic core generates its own magnetic core.

Many interesting facts, stories, secrets of space and the unknown constantly surround us. This is always interesting both from a scientific point of view and from the average person. However, if some space objects are interesting in themselves as extraterrestrial formations, then there are other, truly unique objects, the behavior and nature of which are truly unusual. Such celestial bodies can easily include the satellite Io, one of the four largest satellites of Jupiter.

Volcanic hell, cosmic underworld, hellish furnace - all these epithets refer to the companion, who bears the meek female name Io, taken from ancient Greek mythology.

Behind the ordinary lies the extraordinary

The moon Io, like the other three largest moons of Jupiter, was discovered in 1610. The discovery is attributed to Galileo Galilei, but the great scientist had a co-author. It was the German astronomer Simon Marius, who also managed to discover the moons of Jupiter. Despite the fact that world science gave the palm of discovery to Galileo, it was at the suggestion of Marius that the newly discovered celestial bodies received their names: Io, Europa, Ganymede and Callisto. The German insisted that the entire cosmic retinue of Jupiter should also bear mythical names.

The names of the satellites were given in accordance with the arrangement. The first, the closest satellite of the four to Jupiter, was named in honor of Io, the secret lover of the thunderer Zeus. This combination turned out to be no coincidence. Like the ancient myth in which the beautiful Io was always under the influence of her master, in reality the giant planet constantly dominates its closest satellite. The huge gravitational force field of Jupiter endowed the satellite with the secret of eternal youth - increased geological activity.

The lack of powerful optical instruments for a long time did not allow us to see the distant satellite closely. Only at the beginning of the 20th century did new powerful telescopes make it possible to see the amazing processes occurring on the surface of Io.

The satellite is a spherical body, slightly flattened at the poles. This is clearly visible in the difference between the equatorial and polar radii - 1830 km. versus 1817 km. This unusual shape is explained by the constant influence on the satellite of the gravitational forces of Jupiter and two other neighboring satellites of Europa and Ganymede. The large size corresponds to the mass and fairly high density of the first of the four Galilean satellites. So the mass of the object is 8.94 x 10²² kg. with an average density of 3.55 g/m³, which is slightly less than that of Mars.

The density of other satellites of Jupiter, despite their rather large sizes, decreases with distance from the mother planet. Thus, Ganymede has an average density of 1.93 g/m³, and Callisto has an average density of 1.83 g/m³.

The first of the famous four has the following astrophysical characteristics:

• the period of revolution around the mother planet is 1.77 days;
• the period of rotation around its own axis is 1.769 days;
• at perihelion, Io approaches Jupiter at a distance of 422 thousand km;
• the apohelia of the satellite is 423,400 km;
• the celestial body rushes along an elliptical orbit at a speed of 17.34 km/s.

It should be noted that the satellite Io has both the orbital period and the rotation period, so the celestial body is always turned to its owner with one side. In this position, the fate of the satellite is not visible. The yellow-green poisonous Io makes its run around Jupiter, literally catching the upper edge of the atmosphere of the giant planet at an altitude of 350-370 thousand km. The satellite Io and its neighbors act on it, periodically approaching it, since the orbits of three satellites - Io, Europa and Ganymede - are in orbital resonance.

What is the main feature of Io?

Humanity has become accustomed to the idea that the Earth is the only cosmic body in the solar system that can be called a living organism that has a turbulent geological biography. In fact, it turned out that in addition to us, Io, a satellite of Jupiter, exists in the Solar System, which can be called the most volcanically active object in near space. The surface of the satellite Io is constantly exposed to active geological processes that change its appearance. In terms of the intensity of volcanic eruptions, the strength and power of emissions, poisonous, yellow-green Io is ahead of Earth. This is a kind of constantly boiling and seething cauldron, nestled next to the largest planet in the solar system.

For such a small celestial body, such geological activity is an unusual phenomenon. For the most part, the natural satellites of the Solar System are stable formations of the planetary type, the period of geological activity of which ended many millions of years ago or is in its final stage. Unlike other Galilean satellites of Jupiter, nature itself determined the fate of Io, placing it in close proximity to the mother planet. Io is roughly the size of our Moon. The diameter of the Jupiterian satellite is 3660 km, by 184 km. greater than the diameter of the Moon.

Active volcanism on the moon Io is a constantly ongoing geological process that is not associated either with the age of the celestial body or with the features of its internal structure. Geological activity on the satellite is caused by the presence of its own heat, which is generated as a result of the action of kinetic energy.

Secrets of Io's volcanism

The main secret of the volcanic activity of the satellite of Jupiter lies in its nature, which is caused by the action of tidal forces. It was already mentioned above that the beautiful yellow-green captive is simultaneously affected by the giant gas giant Jupiter and two other satellites - the giant Europa and Ganymede. Due to its close proximity to the mother planet, the surface of Io is distorted by a tidal hump, the height of which reaches several kilometers. Io's slight eccentricity is influenced by Io's sister neighbors Europa and Ganymede. All together leads to the fact that a tidal hump wanders across the surface of the satellite, causing deformation of the crust. The deformation of the crust, the thickness of which is no more than 20-30 km, is pulsating in nature and is accompanied by a colossal release of internal energy.

Under the influence of such processes, the bowels of Jupiter’s satellite heat up to high temperatures, turning into a molten substance. High temperatures and enormous pressure lead to the eruption of molten mantle to the surface.

Currently, scientists have been able to calculate the intensity and strength of the heat flow arising on Io under the influence of tidal forces. In the hottest areas of the satellite, the generation of thermal energy is 108 MW, which is tens of times more than what is produced by all energy facilities on our planet.

The main products of eruptions are sulfur dioxide and sulfur vapor. The following figures indicate the emission power:

• the speed of gaseous release is 1000 km per second;
• Gas plumes can reach heights of 200-300 km.

Every second, up to 100 thousand tons of volcanic material erupts from the bowels of the satellite, which would be enough to cover the surface of the satellite with a ten-meter layer of volcanic rock over millions of years. Lava spreads over the surface, and sedimentary rocks complete the formation of the beauty’s relief. In this regard, only craters of volcanic origin are represented on Io. The changing relief is evidenced by light and dark spots that cover the surface of the satellite with enviable consistency. According to scientists, the dark spots are most likely volcanic calderas, lava river beds and traces of faults.

Studying the surface of the moon Io

The first data about Io were obtained during the flight of the automatic probe Pioneer 10, which back in 1973 provided information about the ionosphere of the Jovian satellite. Subsequently, the study of the distant object continued with the help of the Galileo spacecraft. Today we can say with confidence that Io’s atmosphere is thin and is constantly under the influence of Jupiter. The giant planet seems to lick its companion, removing the air-gas layer from it.

The composition of the atmosphere of the yellow-green celestial body is almost homogeneous. The main component is sulfur dioxide, a product of constant volcanic emissions. Unlike Earth's volcanism, where volcanic emissions contain water vapor, Io is a sulfur factory. Hence the characteristic yellowish tint of the planetary disk of the satellite. As such, the atmosphere of this celestial body has negligible density. Most of the products of volcanic emissions immediately fall to a great height, forming the satellite’s ionosphere.

As for the surface relief of the Jovian satellite, it is mobile and constantly changing. This is evidenced by a comparison of images obtained at different times from two space probes, Voyager 1 and Voyager 2, which flew near Io in 1979 with a difference of four months. Comparison of images made it possible to record changes in the satellite's landscape. The eruption processes continued with almost the same intensity. 16 years later, during the Galileo mission, dramatic changes in the satellite's topography were identified. New volcanoes were identified in recent photographs of previously explored areas. The scale of lava flows has also changed.

Later studies made it possible to measure the temperature on the surface of the object, which on average varies between 130-140⁰С below zero. However, there are also hot areas on Io, where the temperature ranges from zero to 100 degrees plus. As a rule, these are areas of cooling lava, spreading after the next eruption. In the volcanoes, the temperature can reach +300-400⁰ C. The small lakes of red-hot lava on the surface of the satellite are boiling cauldrons in which the temperature rises to 1000 degrees Celsius. As for the volcanoes themselves, the calling card of Jupiter’s satellite, they can be divided into two types:

• the former are small, young formations, the emission height is 100 km, with a gas emission speed of 500 m/s;
• the second type are volcanoes, which are very hot. The height of emissions during eruptions varies between 200-300 km, and the emission speed is 1000 m/s.

The second type includes the largest and oldest volcanoes of Io: Pele, Surt and Aten. Scientists are curious about such an object as Father Loki. Judging by the images taken from the Galileo spacecraft, the formation is a natural reservoir filled with liquid sulfur. The diameter of this boiler is 250-300 km. The size of the patera and the surrounding topography indicate that during an eruption a real apocalypse occurs here. The power of the erupting Loki exceeds the power of the eruptions of all active volcanoes on Earth.

The intensity of Io's volcanism perfectly characterizes the behavior of the Prometheus volcano. This object continues to erupt continuously for 20 years from the moment the processes began to be recorded. Lava does not stop flowing from the crater of another Io volcano - Amirani.

Research into the most volcanically active object in the solar system

The most significant contribution to the study of the first of the Galilean satellites was made by the results of the Galileo mission. The spacecraft, having reached the region of Jupiter, became an artificial satellite of the beautiful Io. In this position, the surface of Jupiter's satellite was photographed during each orbital flight. The device made 35 orbits around this hot object. The value of the information obtained forced NASA scientists to extend the probe's mission for another three years.

Galileo flight path

The flight of the Cassini probe, which on the way to Saturn managed to take several photographs of the yellow-green satellite, added important information for scientists. By examining the satellite in the infrared and ultraviolet, the Cassini probe provided NASA scientists with data on the composition of the ionosphere and the plasma torus of the distant celestial body.

The Galileo space probe, having completed its mission, burned up in September 2003 in the hot embrace of Jupiter's atmosphere. Further study of this most interesting object in the solar system was carried out using earth-based telescopes and using observations from the Hubble orbital telescope.

Flight of New Horizons

Fresh information about the Io satellite began to arrive only after the automatic New Horizons probe reached this region of the Solar System in 2007. The result of this work were photographs that confirmed the version of endlessly continuing volcanic processes that change the appearance of this distant celestial body.

Great hopes for the subsequent study of Io's satellite are associated with the flight of the new Juno space probe, which set off on a long journey in August 2011. Today, this ship has already reached Io’s orbit and become its artificial satellite. The Juno spacecraft company for space exploration around Jupiter should be comprised of a whole flotilla of automatic probes:

• Jupiter Europa Orbiter (NASA);
• Jupiter Ganymede Orbiter (ESA - European Space Agency);
• "Jupiter Magnetospheric Orbiter" (JAXA - Japanese space agency);
• "Jupiter Europa Lander" (Roscosmos).

Flight of Juno

Research on Io's volcanism continues to interest scientists, but general interest in this space object has weakened a little. This is due to the fact that the practical side of studying Jupiter’s satellite has little in common with the plans of earthlings regarding the exploration of outer space. In this regard, other space objects located in the sphere of influence of Jupiter and Saturn look much more interesting. Studying Io's behavior gives scientists information about the natural mechanisms that exist in space. Time will tell whether information about the most volcanically active object in the solar system will be useful. At the moment, the applied aspect of studying Jupiter's satellite Io is not being considered.

Back in 1610, the Italian scientist Galileo Galilei noticed four spots on the disk. The spots appeared and then disappeared again. It was like planets orbiting a star like . This is how the first “moons” of Jupiter were discovered, named after the scientist - Galilean satellites. For almost four hundred years, scientists, astronomers and just amateurs were sure that there were only four satellites. However, in the age of space technology, dozens of Jupiter's moons. All of them, together with the huge giant, form another, small ““. If Jupiter's mass were 4 times its actual mass, then another star system would form. On the Earth's horizon it would be observed two stars: And .

All satellites rotate due to the enormous gravity of Jupiter, their rotation is similar to rotation around. Each “moon” has its own orbits, which are distant from the gas planet at different distances. The closest satellite is Metis is located 128 thousand km from the planet, while the most distant ones are 20-30 million km from their “host”. At the moment, the eyes of scientists and astronomers are directed specifically at the study of 4 Galilean satellites (Io, Europa, Ganymede, Calisto), since they are the largest and most unpredictable moons of Jupiter. These are the most interesting new worlds, each with its own history, mysteries and phenomena.

And about

Satellite name: And about;

Diameter: 3660 km;

Surface area: 41,910,000 km²;

Io was discovered by Galileo on January 8, 1610. It is the closest Galilean satellite. Distance from And about to the outermost layers of Jupiter's atmosphere is almost the same as between and - about 350,000 thousand km. In many basic parameters, the satellite is similar to the Moon. The mass and volume are almost the same, the radius of Io is only 100 km larger than the lunar radius, the gravitational forces of both satellites are also similar (Io - 1.8 m/s², Moon - 1.62 m/s²). Due to its small distance from the planet and its large mass, the gravitational force rotates Io around the planet at a speed of 62,400 km/h (17 times the rotation speed). Thus, a year on Io lasts only 42.5 hours, so the satellite can be observed almost every day.

A characteristic difference between Io and other satellites is the large volcanic activity on its surface. Voyager space stations have recorded 12 active volcanoes spewing hot lava flows up to 300 km high. The main gas emitted is sulfur dioxide, which then freezes on the surface as a white solid. Due to Io's thin atmosphere, such hot gas fountains can be seen even with amateur telescopes. This majestic spectacle can be considered one of the wonders of the solar system. What is the reason for such high volcanic activity on Io?, because its neighbor Europe is a completely frozen world, the surface of which is covered with a multi-kilometer layer of ice. This question is a major mystery for scientists and astronomers. The main version implies that the gravitational influence on Io, both itself and other satellites, caused the creation of two tidal humps on the surface of the satellite. Since Io's orbit is not an exact circle, as it rotates around Jupiter, the humps move slightly across Io's surface, which leads to heating of the interior. Nearest "moon" Jupiter is squeezed into a gravitational ring between the planet itself and the rest of its satellites (mainly between and Europa). On this basis, it should be noted that Io is the most volcanically active body .

Volcanic activity is quite common on Io. Sulfur emissions may
rise to a height of 300 km, some of them fall to the surface, forming
lava seas, and some remain in outer space

Europe

Satellite name: Europe;

Diameter: 3122 km;

Surface area: 30,613,000 km²;

Volume: 1.59×10 10 km³;

Weight: 4.8×10 22 kg;

Density t: 3013 kg/m³;

Rotation period: 3.55 days;

Circulation period: 3.55 days;

Distance from Jupiter: 671,000 km;

Orbital speed: 13.74 km/s;

Equator length: 9,807 km;

Orbital inclination: 1.79°;

Acceleration free fall: 1.32 m/s²;

Satellite: Jupiter

Europe is the sixth satellite of Jupiter or the second of the Galilean group. Its almost circular orbit is located at a distance of 671 thousand kilometers from the Gas Giant. The satellite needs 3 days 13 hours and 12 minutes to turn around, while Io manages to complete two revolutions during this time.
At first sight Europe- This is a world completely frozen and devoid of all life. There are no energy sources on its surface, and due to the large distance from the center, the satellite receives virtually no solar heat. This also includes an atmosphere that is too thin and cannot retain heat for a long time. However, the sixth moon has something that not only other satellites of the planet do not have, but also all bodies (except). The surface of Jupiter is covered with a 100 kilometer layer water. This amount of water exceeds the volume of the earth's oceans and seas combined. The atmosphere, although thin, still consists entirely of oxygen (an element without which all Earthly creatures would die). It would seem that since there is oxygen and water, it means that life will begin. However, the upper layer, 10-30 km thick, is in a solid ice state, forming a very dense frozen crust, in which there are no active movements. But underneath its thickness there is enough heat to turn water into a liquid phase in which a wide variety of inhabitants of the underwater world can live. In the near future, humanity plans to direct Europe such a robot that could drill through a multi-kilometer layer of ice, dive into the thickness of the ocean and get acquainted with the local underwater inhabitants. At the end of its mission, such a device will have to rise to the surface of the satellite and deliver extraterrestrial beings to our planet.

A spacecraft (as imagined by the artist) that will pass through

Europa's icy crust and will begin to study the oceanic part of the satellite

Geological history of Europe has nothing to do with the history of other satellites. It is one of the smoothest solids in . There are no hills on Europa more than 100 m high, and its entire surface looks like one large plain of frozen ice. Its entire young surface is covered with a network of light and dark narrow stripes of enormous length. Dark stripes thousands of kilometers long are traces of a global system of cracks that arose as a result of repeated heating of the ice crust from internal stresses and large-scale tectonic processes.

Back in 1610, the Italian scientist Galileo Galilei noticed four spots on the disk of Jupiter. The spots appeared and then disappeared again. It was similar to the rotation of planets around a star like the Sun. This is how the first “moons” of Jupiter were discovered, named after the scientist - Galilean satellites. For almost four hundred years, scientists, astronomers and just amateurs were sure that Jupiter only had four satellites. However, in the age of space technology, dozens of Jupiter's moons. All of them, together with the huge giant, form another, small “Solar System”. If Jupiter's mass were 4 times its actual mass, then another star system would form. On the Earth's horizon it would be observed two stars: Sun and Jupiter.

All satellites rotate due to the enormous gravity of Jupiter, their rotation is similar to the rotation of the Moon around the Earth. Each “moon” has its own orbits, which are distant from the gas planet at different distances. The closest satellite of Jupiter is Metis is located 128 thousand km from the planet, while the most distant ones are 20-30 million km from their “host”. At the moment, the eyes of scientists and astronomers are directed specifically at the study of 4 Galilean satellites (Io, Europa, Ganymede, Calisto), since they are the largest and most unpredictable moons of Jupiter. These are the most interesting new worlds, each with its own history, mysteries and phenomena.

And about

Satellite name: And about;

Diameter: 3660 km;

Surface area: 41,910,000 km²;

Io was discovered by Galileo on January 8, 1610. It is the closest Galilean moon of Jupiter. Distance from And about to the outermost layers of Jupiter's atmosphere is almost the same as between the Moon and Earth - about 350,000 thousand km. In many basic parameters, the satellite is similar to the Moon. The mass and volume are almost the same, the radius of Io is only 100 km larger than the lunar radius, the gravitational forces of both satellites are also similar (Io - 1.8 m/s², Moon - 1.62 m/s²). Due to the small distance from the planet and the large mass of Jupiter, the gravitational force rotates Io around the planet at a speed of 62,400 km/h (17 times the rotation speed of the Moon). Thus, a year on Io lasts only 42.5 hours, so the satellite can be observed almost every day.

A characteristic difference between Io and other moons of Jupiter is the large volcanic activity on its surface. Voyager space stations have recorded 12 active volcanoes spewing hot lava flows up to 300 km high. The main gas emitted is sulfur dioxide, which then freezes on the surface as a white solid. Due to Io's thin atmosphere, such hot gas fountains can be seen even with amateur telescopes. This majestic spectacle can be considered one of the wonders of the solar system. What is the reason for such high volcanic activity on Io?, because its neighbor Europe is a completely frozen world, the surface of which is covered with a multi-kilometer layer of ice. This question is a major mystery for scientists and astronomers. The main version implies that the gravitational influence on Io, both Jupiter itself and other satellites, caused the creation of two tidal humps on the surface of the satellite. Since Io's orbit is not an exact circle, as it rotates around Jupiter, the humps move slightly across Io's surface, which leads to heating of the interior. Nearest "moon" Jupiter is sandwiched in a gravitational ring between the planet itself and the rest of its satellites (mainly between Jupiter and Europa). On this basis, it should be noted that Io is the most volcanically active body Solar system.

Volcanic activity is quite common on Io. Sulfur emissions may
rise to a height of 300 km, some of them fall to the surface, forming
lava seas, and some remain in outer space

Europe

Satellite name: Europe;

Diameter: 3122 km;

Surface area: 30,613,000 km²;

Volume: 1.59×10 10 km³;

Weight: 4.8×10 22 kg;

Density t: 3013 kg/m³;

Rotation period: 3.55 days;

Circulation period: 3.55 days;

Distance from Jupiter: 671,000 km;

Orbital speed: 13.74 km/s;

Equator length: 9,807 km;

Orbital inclination: 1.79°;

Acceleration free fall: 1.32 m/s²;

Satellite: Jupiter

Europe is the sixth satellite of Jupiter or the second of the Galilean group. Its almost circular orbit is located at a distance of 671 thousand kilometers from the Gas Giant. It takes the satellite 3 days, 13 hours and 12 minutes to orbit Jupiter, while Io manages to complete two revolutions during this time.
At first sight Europe- This is a world completely frozen and devoid of all life. There are no energy sources on its surface, and due to its large distance from the center of the Solar System, the satellite receives virtually no solar heat. This also includes an atmosphere that is too thin and cannot retain heat for a long time. However, the sixth moon of Jupiter has something that not only the other satellites of the planet do not have, but also all the bodies of the Solar System (except the Earth). The surface of Jupiter is covered with a 100 kilometer layer water. This amount of water exceeds the volume of the earth's oceans and seas combined. The atmosphere, although thin, still consists entirely of oxygen (an element without which all Earthly creatures would die). It would seem that since there is oxygen and water, it means that life will begin. However, the upper layer, 10-30 km thick, is in a solid ice state, forming a very dense frozen crust, in which there are no active movements. But underneath its thickness there is enough heat to turn water into a liquid phase in which a wide variety of inhabitants of the underwater world can live. In the near future, humanity plans to direct Europe such a robot that could drill through a multi-kilometer layer of ice, dive into the thickness of the ocean and get acquainted with the local underwater inhabitants. At the end of its mission, such a device will have to rise to the surface of the satellite and deliver extraterrestrial beings to our planet.

A spacecraft (as imagined by the artist) that will pass through

Europa's icy crust and will begin to study the oceanic part of the satellite

Geological history of Europe has nothing to do with the history of other moons of Jupiter. It is one of the smoothest solid bodies in the Solar System. There are no hills on Europa more than 100 m high, and its entire surface looks like one large plain of frozen ice. Its entire young surface is covered with a network of light and dark narrow stripes of enormous length. Dark stripes thousands of kilometers long are traces of a global system of cracks that arose as a result of repeated heating of the ice crust from internal stresses and large-scale tectonic processes.