Neptune is a planet 8 counted from the Sun. Interesting Facts

Neptune is a planet, the eighth from the sun. In some places, its orbit intersects with the orbit of Pluto. Which planet is Neptune? It is classified as a giants. The astrological sign is J.

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The giant planet Neptune produces a movement around the sun in an elliptical orbit that is close to circular. The length of the radius is 24,750 kilometers. This figure is four times greater than that of the Earth. Own speed of rotation of the planet is so fast that the duration of the day here is 17.8 hours.

Planet Neptune from the Sun is removed by about 4,500 million kilometers, therefore, light reaches the object in question in little more than four hours.

Although the average density of Neptune is almost three times less than that of the Earth (it is 1.67 g / cm³), its mass is 17.2 times higher. This is due to the large size of the planet.

Features of composition, physical conditions and structure

Neptune and Uranus are planets based on solidified gases with a 15% hydrogen content and a small amount of helium. As scientists suggest, the blue giant does not have a clear internal structure. The most likely is the fact that inside Neptune there is a dense nucleus of small dimensions.

The atmosphere of the planet is made up of helium and hydrogen with minor impurities of methane. On Neptune, there are often great storms, in addition, it is characterized by vortices and strong winds. The latter are blowing in the west direction, their speed can reach up to 2200 km / h.

It was noted that the velocity of currents and currents in giant planets increases with distance from the Sun. Explanations of this pattern have not yet been found. Thanks to the photographs taken by special equipment in the atmosphere of Neptune, it became possible to examine the clouds in detail. Just like Saturn or Jupiter, this planet has an internal heat source. It can emit up to three times more energy than it receives from the Sun.

Giant step forward

According to historical documents, Galileo saw Neptune on December 28, 1612. The second time he managed to observe an unknown cosmic body on January 29, 1613. In both cases, the scientist accepted the planet as a fixed star, which is in conjunction with Jupiter. For this reason, Neptune's discovery is not attributed to Galileo.

It is established that during the observation period of 1612 the planet was at a standpoint, and just on the day when Galileo first saw her, she turned to the backward movement. This process is observed in the case when the Earth in its orbit overtakes the outer planet. Since Neptune was not far from the point of standing, his movement was too weak to be noticed by Galileo's insufficiently strong telescope.

In 1781, Herschel succeeded in discovering Uranus. Then the scientist calculated the parameters of his orbit. Based on the obtained data, Herschel concluded that there are mysterious anomalies in the process of the motion of this space object: it was ahead of the calculated one, then lagged behind it. This fact allowed to assume that beyond Uranus is another planet, gravitational attraction distorting the trajectory of its motion.

In 1843, Adams managed to calculate the orbit of the mysterious eighth planet in order to explain the changes in the orbit of Uranus. The scientist sent information about his work to the astronomer of the King - J. Eyri. Soon he received a response letter requesting clarification on some issues. Adams began to make the required sketches, but for some reason he did not send the message and subsequently did not initiate serious work on this issue.

The immediate discovery of the planet Neptune was due to the efforts of Leverrier, Halle and d'Aire. On September 23, 1846, having the data on the system of the orbit elements of the object sought, they proceeded to work on determining the exact location of the mysterious object. The first evening their efforts were crowned with success. The discovery of the planet Neptune at that time was called the triumph of celestial mechanics.

Choose a name

After the discovery of the giant, they began to think about what name to give to him. The very first version was proposed by Johann Halle. He wanted to baptize the distant cosmic object Janus in honor of the god, symbolizing the beginning and end in Roman mythology, but this name was not to the liking of many. A much warmer proposal was received from Struve, the director of the Pulkovo Observatory. His version - Neptune - and became final. Assignment of the official name to the giant planet put an end to numerous disputes and disagreements.

How did the idea of Neptune change?

Sixty years ago, information about the blue giant differed from today's. Although it was relatively accurately known about the sidereal and synodic periods of rotation around the Sun, about the inclination of the equator to the plane of the orbit, there were data set less accurately. Thus, the mass was estimated at 17.26 terrestrial instead of real 17.15, and the equatorial radius - at 3.89, and not 3.88 from our planet. As for the stellar period of revolution around the axis, it was believed that it is 15 hours 8 minutes, which is fifty minutes less than the real one.

In some other parameters, too, there were inaccuracies. For example, before Voyager 2 approached Neptune, as far as possible, it was assumed that the magnetic field of a planet is similar in its configuration to the terrestrial one. In fact, it looks like a so-called inclined rotator.

A little bit about orbital resonances

Neptune is able to act on the Kuiper belt located at a great distance from it. The latter is represented by a ring of small ice planets, similar to the asteroid belt between Jupiter and Mars, but with a much greater extent. The Kuiper Belt is under the significant influence of the gravitational force of Neptune's attraction, as a result of which even gaps formed in its structure.

The orbits of those objects that are held in the indicated belt for a long period are established by the so-called secular resonances with Neptune. In certain cases this time is comparable to the period of the existence of the solar system.

Zones of Neptune's gravitational stability are called Lagrange points. In them, the planet retains a large number of asteroids-Trojans, as if dragging them along along the entire orbit.

Features of the internal structure

In this regard, Neptune is similar to Uranus. The atmosphere accounts for about twenty percent of the total mass of the planet in question. The closer to the core, the higher the pressure. The maximum figure is about 10 GPa. In the lower layers of the atmosphere, there are concentrations of water, ammonia and methane.

Elements of the internal structure of Neptune:

• Upper clouds and atmosphere.
• The atmosphere formed by hydrogen, helium and methane.
• Mantle (methane ice, ammonia, water).
• Stone-ice core.

Climatic characteristic

One of the differences between Neptune and Uranus is the degree of meteorological activity. According to data obtained from the Voyager 2, the weather on the blue giant is changing often and significantly.

It was possible to identify an extremely dynamic system of storms with winds that reach speeds of even 600 m / s - almost supersonic (most of them blow in the direction opposite to Neptune's rotation around its own axis).

In 2007, it was revealed that the upper troposphere of the south pole of the planet is ten degrees Celsius warmer than in other parts where the temperature is about -200 ° C. Such a difference is sufficient to ensure that methane from other zones of the upper part of the atmosphere seeps into space in the region of the South Pole. The resulting "hot spot" is a consequence of the axial inclination of the blue giant, whose south pole has been turned to the Sun for forty years now. As Neptune slowly moves along the orbit to the opposite side of this heavenly celestial body, the south pole gradually disappears completely into the shadow. Thus, Neptune will expose the Sun to its north pole. Consequently, the zone of methane release into space will move to this part of the planet.

"Accompanying" the giant

Neptune - a planet that has, according to today's data, eight satellites. Among them there is one big, three medium and four small. Let us consider in more detail the three largest.

Triton

It is the largest satellite that has the giant planet Neptune. It was discovered by W. Lassell in 1846. Triton is 394,700 km away from Neptune, its radius is 1600 km. As expected, he has an atmosphere. In size, the object is close to the moon. According to scientists, before the capture of Neptune Triton was an independent planet.

Nereid

This is the second largest satellite of the planet in question. On average, it was removed from Neptune by 6.2 million kilometers. The radius of Nereid is 100 kilometers, and the diameter is twice as large. In order to make one revolution around Neptune, this satellite requires 360 days, that is, almost the entire earthly year. The discovery of Nereid occurred in 1949.

Proteus

This planet takes the third place not only in size, but also in remoteness from Neptune. It can not be said that Proteus has some special characteristics, but it was his scientists who chose to create a three-dimensional interactive model, based on the images of the Voyager-2.

The remaining satellites are small planets, of which there are a great many in the solar system.

Features of the study

Neptune - a planet which counts from the sun? The eighth. If you know exactly where this giant is, you can see it even in powerful binoculars. Neptune is quite difficult to study by the cosmic body. This is partly due to the fact that its brightness is slightly higher than the eighth magnitude value. For example, one of the above-mentioned satellites - Triton - has a brilliance equal to fourteen magnitude. In order to discover the disk of Neptune, it is required to apply large magnifications.

The Voyager 2 spacecraft managed to reach an object such as Neptune. The planet (see photo in the article) received the guest from the Earth in August 1989. Thanks to the data collected by this ship, scientists have at least some information about this mysterious object.

Data from the Voyager

Neptune is a planet that had a Great Dark Spot in the southern hemisphere. This is the most famous detail about the object, obtained as a result of the operation of the spacecraft. By diameter, this Spot was almost equal to the Earth. The winds of Neptune carried it with a huge speed of 300 m / s in the west.

According to observations of HST (Hubble Space Telescope) for 1994, the Great Dark Spot disappeared. It is assumed that it either dissipated, or turned out to be closed by other parts of the atmosphere. A few months later, thanks to the Hubble telescope, it was possible to find a new spot, which is already in the northern hemisphere of the planet. On the basis of this, it can be concluded that Neptune is a planet whose atmosphere is changing rapidly - presumably because of slight fluctuations in the temperatures of the lower and upper clouds.

Thanks to Voyager 2, it is established that the object described has rings. Their presence was revealed in 1981, when one of the stars eclipsed Neptune. Observations from the Earth did not bring any special result: instead of full rings, only weak arcs were seen. Voyager 2 came to the rescue again. In 1989, the apparatus made detailed images of the rings. One of them has an interesting curved structure.

What is known about the magnetosphere

Neptune is a planet whose magnetic field is rather strange. The magnetic axis is 47 degrees inclined to the axis of rotation. On Earth this would be reflected in the unusual behavior of the compass needle. So, the North Pole would be located south of Moscow. Another unusual fact is that in Neptune the axis of symmetry of the magnetic field does not pass through its center.

Unanswered Questions

- Why are there such strong winds on Neptune, while it is very far from the Sun? To implement such processes, the internal heat source located deep in the planet is not strong enough.

- Why is the object lacking hydrogen and helium?

- How to develop a relatively inexpensive project to fully explore Uranus and Neptune using spacecraft?

- Because of what processes is formed the unusual magnetic field of the planet?

Modern research

The creation of accurate models of Neptune and Uranus in order to clearly describe the formation of ice giants proved to be a difficult task. To explain the evolution of these two planets have put forward a considerable number of hypotheses. According to one of them, both giants appeared due to instability inside the base protoplanetary disk, and later their atmospheres were literally blown off by the radiation of a large B or O star.

According to another concept, Neptune and Uranus were formed relatively near the Sun, where the density of matter is higher, and then moved to current orbits. This hypothesis has become the most common, because it can explain the existing resonances in the Kuiper belt.

Observations

Neptune - which planet from the sun? The eighth. And it is not possible to see it with the naked eye. The indicator of the stellar magnitude of the giant is between +7.7 and +8.0. Thus, it is duller than many celestial objects, including the dwarf planet Ceres, the moons of Jupiter and some asteroids. For the organization of qualitative observations of the planet, a telescope with at least two hundred times magnification and a diameter of 200-250 millimeters is required. With 7x50 binoculars, the blue giant will be visible as a weak star.

The change in the angular diameter of the cosmic object in question is within 2.2-2.4 angular seconds. This is due to the fact that at a very large distance from the Earth is the planet Neptune. Facts about the state of the surface of the blue giant was extremely difficult to extract. Much has changed with the advent of the Hubble Space Telescope and the most powerful ground-based instruments equipped with adaptive optics.

Observations of the planet in the radio-wave band made it possible to establish that Neptune is a source of irregular bursts and also of continuous radiation. Both phenomena are explained by the rotating magnetic field of the blue giant. On a colder background in the infrared zone of the spectrum, the disturbances in the depths of the atmosphere of the planet are clearly seen - the so-called storms. They are generated by the heat emanating from the shrinking core. Thanks to observations, you can determine their size and shape as accurately as possible, and track movements.

Mysterious planet Neptune. Interesting Facts

- For almost a century, this blue giant was considered the farthest in the entire solar system. And even the discovery of Pluto has not changed this belief. Neptune - what kind of planet is it? The eighth, not the last, the ninth. Nevertheless, he sometimes turns out to be farthest from our luminary. The fact is that Pluto has an elongated orbit, which is sometimes closer to the Sun than the orbit of Neptune. The blue giant managed to regain the status of the farthest planet. And all thanks to the fact that Pluto was transferred to the category of dwarf objects.

- Neptune has the smallest size among the four known gas giants. Its equatorial radius is less than that of Uranus, Saturn and Jupiter.

"As on all the gas planets, Neptune does not have a solid surface. Even if the spacecraft managed to reach him, he could not land. Instead, there would be an immersion in the interior of the planet.

- Neptune's gravity is a little more than the earth's (by 17%). Hence, the force of attraction acts on both planets almost equally.

- In order to turn around the Sun, Neptune needs 165 Earth years.

- The blue saturated color of the planet is explained by the most powerful lines of such gas as methane, prevailing in the reflected light of the giant.

Conclusion

In the process of space exploration, an enormous role was played by the discovery of the planets. Neptune and Pluto, as well as other objects, were discovered as a result of the laborious work of many astronomers. Most likely, what is now known to mankind about the universe is only a small part of the real picture. The cosmos is a great mystery, and it will take many centuries to solve it.