Although, of course, the word “giant” will be a little strong in relation to Neptune, a planet that, although very large by cosmic standards, is, nevertheless, significantly inferior in size to our other giant planets: Saturn, Saturn, etc. Speaking of Uranus, although this planet is larger in size than Neptune, in terms of mass Neptune is still 18% larger than Uranus. In general, this planet, named because of its blue color To honor the ancient god of the seas, Neptune can be considered the smallest of the giant planets and at the same time the most massive - Neptune’s density is many times stronger than that of other planets. But compared to Neptune and our Earth, they are tiny, if you imagine that our Sun is the size of a door, then the Earth is the size of a coin, and Neptune is the same in size as a large baseball.
The history of the discovery of the planet Neptune
The history of the discovery of Neptune is unique in its kind, since it is the first planet in our solar system that was discovered purely theoretically, thanks to mathematical calculations, and only then was it noticed through a telescope. It was like this: back in 1846, French astronomer Alexis Bouvard observed the movement of the planet Uranus through a telescope and noticed strange deviations in its orbit. The anomaly in the movement of the planet, in his opinion, could be caused by a strong gravitational influence some other large celestial body. Alexis’s German colleague, astronomer Johann Halle, made the necessary mathematical calculations to determine the location of this previously unknown planet, and they turned out to be correct - soon our Neptune was discovered at the site of the supposed location of the unknown “Planet X”.
Although long before this, the planet Neptune was observed in a telescope by the great. True, in his astronomical notes he noted it as a star, not a planet, so the discovery was not credited to him.
Neptune is the most distant planet in the solar system
“But what about?”, you probably ask. In fact, everything here is not as simple as it seems at first glance. Since its discovery in 1846, Neptune has rightfully been considered the farthest planet from the Sun. But in 1930, little Pluto was discovered, which is even further away. There’s just one nuance here: Pluto’s orbit is strongly elongated along an ellipse in such a way that certain moments its movement, Pluto turns out to be closer to the Sun than Neptune. The last time such an astronomical phenomenon occurred was from 1978 to 1999 - for 20 years, Neptune again had the title of the full-fledged “farthest planet from the Sun.”
Some astronomers, in order to get rid of these confusions, even proposed to “demote” Pluto from the title of planet, they say, it’s just a small celestial body, flying in orbit, or assign the status of a “dwarf planet”, however, disputes on this matter are still ongoing.
Features of the planet Neptune
Neptune has its bright blue appearance due to the strong density of clouds in the planet’s atmosphere; these clouds conceal within themselves still completely unknown to our science chemical compounds, which when absorbed sunlight are painted blue. One year on Neptune is equal to our 165 years, which is the time it takes Neptune to complete its full cycle in its orbit around the Sun. But a day on Neptune is not as long as a year; it is even shorter than ours on Earth, since it lasts only 16 hours.
Neptune temperature
Because sun rays They reach the distant “blue giant” in very small numbers; it is natural that on its surface it is very, very cold - the average surface temperature there is -221 degrees Celsius, which is two times lower than the freezing point of water. In a word, if you were on Neptune, you would turn into ice in the blink of an eye.
Surface of Neptune
Neptune's surface consists of ammonia and methane ice, but the planet's core may well turn out to be rock, but this is still just a hypothesis. It is curious that the force of gravity on Neptune is very similar to that of Earth, it is only 17% greater than ours, and this despite the fact that Neptune is 17 times larger than Earth. Despite this, we are unlikely to be able to walk around Neptune in the near future, see the previous paragraph about the ice. And besides, strong winds blow on the surface of Neptune, the speed of which can reach up to 2400 kilometers per hour (!), perhaps on no other planet in our solar system there are such strong winds as here.
Neptune size
As mentioned above, it is 17 times larger than our Earth. The picture below shows a comparison of the sizes of our planets.
Atmosphere of Neptune
The composition of Neptune's atmosphere is similar to the atmospheres of most similar giant planets: it is mainly dominated by hydrogen and helium atoms, and also contains small amounts of ammonia, frozen water, methane and others chemical elements. But unlike others major planets Neptune's atmosphere contains a lot of ice, due to its remote location.
Rings of the planet Neptune
Surely when you hear about planetary rings, Saturn immediately comes to mind, but in fact, it is far from the only owner of rings. Our Neptune also has rings, although not as large and beautiful as those of the planet. Neptune has five rings in total, named after the astronomers who discovered them: Halle, Le Verrier, Lascelles, Arago and Adams.
Neptune's rings consist of small pebbles and cosmic dust (many micron-sized particles), their structure is somewhat similar to the rings of Jupiter and they are quite difficult to notice, since they are black. Scientists believe that Neptune's rings are relatively young, at least much younger than the rings of its neighbor Uranus.
Moons of Neptune
Neptune, like any decent giant planet, has its own satellites, not just one, but thirteen, named after the smaller sea gods of the ancient pantheon.
Particularly interesting is the satellite Triton, discovered, in part, thanks to... beer. The fact is that the English astronomer William Lasing, who actually discovered Triton, made a large fortune by brewing and trading beer, which subsequently allowed him to invest a lot of money and time in his favorite hobby - astronomy (especially since equipping a high-quality observatory is not cheap).
But what is interesting and unique about Triton? The fact is that this is the only known satellite in our solar system that rotates around the planet in the opposite direction relative to the rotation of the planet itself. In scientific terminology, this is called “retrograde orbit.” Scientists suggest that Triton was not previously a satellite at all, but an independent dwarf planet (like Pluto), which, by the will of fate, fell into the sphere of influence of Neptune’s gravity, essentially captured by the “blue giant.” But it doesn't end there: Neptune's gravity pulls Triton closer and closer, and after several million light years, gravitational forces can tear the satellite apart.
How long does it take to fly to Neptune?
For a long time. This is, in short, when modern technologies, of course. After all, the distance from Neptune to the Sun is 4.5 billion kilometers, and the distance from Earth to Neptune is 4.3 billion kilometers, respectively. The only satellite sent from Earth to Neptune, Voyager 2, launched in 1977, reached its destination only in 1989, where it photographed the “big dark spot"on the surface of Neptune and observed a series of powerful storms in the planet's atmosphere.
Planet Neptune video
And at the end of our article, we offer you an interesting video about the planet Neptune.
>Neptune's surface
Surface of the planet Neptune– ice giant of the Solar system: composition, structure with photos, temperature, dark spot from Hubble, Voyager 2 study.
Neptune belongs to the family of ice giants in the solar system, and therefore does not have a solid surface. The blue-green haze we observe is the result of an illusion. These are the tops of deep gas clouds that give way to water and other molten ice.
If you try to walk on the surface of Neptune, you will immediately fall down. During descent the temperature and pressure will increase. So the surface point is marked at the place where the pressure reaches 1 bar.
Composition and structure of Neptune's surface
With a radius of 24,622 km, Neptune is the 4th largest among solar planets. Its mass (1.0243 x 10 26 kg) is 17 times greater than that of Earth. The presence of methane absorbs red wavelengths and rejects blue ones. Below is a drawing of the structure of Neptune.
Consists of a rocky core (silicates and metals), a mantle (water, methane and ammonia ices), as well as helium, methane and hydrogen atmospheres. The latter is divided into the troposphere, thermosphere and exosphere.
In the troposphere, temperature decreases with altitude, and in the stratosphere it increases with increasing altitude. In the first, the pressure is kept at 1-5 bar, which is why the “surface” is located here.
The top layer consists of hydrogen (80%) and helium (19%). Cloud formations can be noted. At the top, the temperature allows methane to condense, and there are also ammonia, water, ammonium sulfide and hydrogen sulfide clouds. In the lower areas, the pressure reaches 50 bar and the temperature mark is 0.
High heating is observed in the thermosphere (476.85°C). Neptune is extremely far from the star, so a different heating mechanism is needed. This could be the contact of the atmosphere with ions in the magnetic field or gravitational waves of the planet itself.
The surface of Neptune is devoid of hardness, so the atmosphere rotates differentially. The equatorial part rotates with a period of 18 hours, the magnetic field - 16.1 hours, and the polar zone - 12 hours. This is why strong winds occur. Three large ones were recorded by Voyager 2 in 1989.
The first storm extended over 13,000 x 6,600 km and looked like Jupiter's Great Red Spot. In 1994, the Hubble telescope tried to find the Great Dark Spot, but it was not there. But a new one has formed on the territory of the northern hemisphere.
Scooter is another storm represented by light cloud cover. They are located south of the Great Dark Spot. In 1989, the Little Dark Spot was also noticed. At first it seemed completely dark, but when the device got closer, it was possible to detect a bright core.
Internally warm
No one yet knows why Neptune warms up inside. The planet is located last, but is in the same temperature category as Uranus. In fact, Neptune produces 2.6 times more energy than it receives from the star.
Internal heating combined with frosty space results in severe temperature fluctuations. Winds are formed that can accelerate to 2100 km/h. Inside there is a rocky core that warms up to thousands of degrees. You can see what the surface of Neptune is on top photo to remember the main formations of the giant's atmosphere.
Neptune is the eighth and outermost planet in the solar system. Neptune is also the fourth largest planet in diameter and third largest in mass. The mass of Neptune is 17.2 times, and the diameter of the equator is 3.9 times greater than that of the Earth. The planet was named after the Roman god of the seas.
Discovered on September 23, 1846, Neptune became the first planet discovered through mathematical calculations rather than through regular observations. The discovery of unforeseen changes in the orbit of Uranus gave rise to the hypothesis of an unknown planet, the gravitational disturbing influence of which caused them. Neptune was found within its predicted position. Soon its satellite Triton was discovered, but the remaining 13 satellites known today were unknown until the 20th century. Neptune has only been visited by one spacecraft, Voyager 2, which flew close to the planet on August 25, 1989.
Neptune is similar in composition to Uranus, and both planets differ in composition from the larger giant planets Jupiter and Saturn. Sometimes Uranus and Neptune are placed in a separate category of "ice giants." Neptune's atmosphere, like that of Jupiter and Saturn, consists mainly of hydrogen and helium, along with traces of hydrocarbons and possibly nitrogen, but contains a higher proportion of ices: water, ammonia, and methane. The core of Neptune, like Uranus, consists mainly of ice and rocks. Traces of methane in the outer layers of the atmosphere are, in part, responsible for the planet's blue color.
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| Planet Discovery: | |
| Discoverer | Urbain Le Verrier, Johann Halle, Heinrich d'Arre |
| Opening place | Berlin |
| Opening date | September 23, 1846 |
| Detection method | calculation |
| Orbital characteristics: | |
| Perihelion | 4,452,940,833 km (29.76607095 AU) |
| Aphelion | 4,553,946,490 km (30.44125206 AU) |
| Major axle shaft | 4,503,443,661 km (30.10366151 AU) |
| Orbital eccentricity | 0,011214269 |
| Sidereal period of revolution | 60,190.03 days (164.79 years) |
| Synodic period of revolution | 367.49 days |
| Orbital speed | 5.4349 km/s |
| Average anomaly | 267.767281° |
| Mood | 1.767975° (6.43° relative to the solar equator) |
| Longitude of the ascending node | 131.794310° |
| Periapsis argument | 265.646853° |
| Satellites | 14 |
| Physical characteristics: | |
| Polar compression | 0.0171 ± 0.0013 |
| Equatorial radius | 24,764 ± 15 km |
| Polar radius | 24,341 ± 30 km |
| Surface area | 7.6408 10 9 km 2 |
| Volume | 6.254 10 13 km 3 |
| Weight | 1.0243 10 26 kg |
| Average density | 1.638 g/cm 3 |
| Acceleration of free fall at the equator | 11.15 m/s 2 (1.14 g) |
| Second escape velocity | 23.5 km/s |
| Equatorial rotation speed | 2.68 km/s (9648 km/h) |
| Rotation period | 0.6653 days (15 hours 57 minutes 59 seconds) |
| Axis tilt | 28.32° |
| Right ascension north pole | 19h 57m 20s |
| North pole declination | 42.950° |
| Albedo | 0.29 (Bond), 0.41 (geom.) |
| Apparent magnitude | 8.0-7.78m |
| Angular diameter | 2,2"-2,4" |
| Temperature: | |
| level 1 bar | 72 K (about -200 °C) |
| 0.1 bar (tropopause) | 55 K |
| Atmosphere: | |
| Compound: | 80±3.2% hydrogen (H 2) 19±3.2% helium 1.5±0.5% methane approximately 0.019% hydrogen deuteride (HD) approximately 0.00015% ethane |
| Ice: | ammonia, aqueous, ammonium hydrosulfide (NH 4 SH), methane |
| PLANET NEPTUNE | |
Neptune's atmosphere is home to the strongest winds of any planet in the solar system; according to some estimates, their speeds can reach 2,100 km/h. During the flyby of Voyager 2 in 1989, the so-called Great Dark Spot, similar to the Great Red Spot on Jupiter, was discovered in the southern hemisphere of Neptune. The temperature of Neptune in the upper atmosphere is close to -220 °C. At the center of Neptune, the temperature ranges, according to various estimates, from 5400 K to 7000-7100 °C, which is comparable to the temperature on the surface of the Sun and comparable to the internal temperature of most known planets. Neptune has a faint and fragmented ring system, possibly discovered as early as the 1960s, but only reliably confirmed by Voyager 2 in 1989.
July 12, 2011 marks exactly one Neptunian year - or 164.79 Earth years - since the discovery of Neptune on September 23, 1846.
Physical characteristics:
With a mass of 1.0243·10 26 kg, Neptune is an intermediate link between the Earth and the large gas giants. Its mass is 17 times that of Earth, but is only 1/19 of the mass of Jupiter. Neptune's equatorial radius is 24,764 km, which is almost 4 times that of Earth. Neptune and Uranus are often considered a subclass gas giants, which are called "ice giants" due to their smaller size and lower concentration of volatiles.
The average distance between Neptune and the Sun is 4.55 billion km (about 30.1 average distance between the Sun and Earth, or 30.1 AU), and it takes 164.79 years to complete a revolution around the Sun. The distance between Neptune and Earth is between 4.3 and 4.6 billion km. On July 12, 2011, Neptune completed its first full orbit since the discovery of the planet in 1846. From Earth it was visible differently than on the day of discovery, as a result of the fact that the period of the Earth's revolution around the Sun (365.25 days) is not a multiple of the period of Neptune's revolution. The planet's elliptical orbit is inclined 1.77° relative to Earth's orbit. Due to the presence of an eccentricity of 0.011, the distance between Neptune and the Sun changes by 101 million km - the difference between perihelion and aphelion, that is, the closest and most distant points of the planet’s position along the orbital path. Neptune's axial tilt is 28.32°, which is similar to the axial tilt of Earth and Mars. As a result, the planet experiences similar seasonal changes. However, due to Neptune's long orbital period, the seasons last about forty years each.
The sidereal rotation period for Neptune is 16.11 hours. Due to an axial tilt similar to Earth's (23°), changes in the sidereal rotation period during its long year are not significant. Since Neptune does not have a solid surface, its atmosphere is subject to differential rotation. The broad equatorial zone rotates with a period of approximately 18 hours, which is slower than the 16.1 hour rotation magnetic field planets. In contrast to the equator, the polar regions rotate every 12 hours. Among all the planets of the Solar System, this type of rotation is most pronounced in Neptune. This leads to a strong latitudinal wind shift.
Neptune has a great influence on the Kuiper Belt, which is very distant from it. The Kuiper Belt is a ring of icy small planets, similar to the asteroid belt between Mars and Jupiter, but much more extensive. It ranges from the orbit of Neptune (30 AU) to 55 astronomical units from the Sun. Gravitational force Neptune's gravity has the most significant effect on the Kuiper belt (including in terms of the formation of its structure), comparable in proportion to the influence of Jupiter's gravity on the asteroid belt. During the existence of the Solar System, some regions of the Kuiper Belt were destabilized by Neptune's gravity, and gaps appeared in the structure of the belt. An example is the area between 40 and 42 a. e.
The orbits of objects that can be held in this belt for a sufficiently long time are determined by the so-called. age-old resonances with Neptune. For some orbits, this time is comparable to the time of the entire existence of the Solar System. These resonances appear when the orbital period of an object around the Sun is related to the orbital period of Neptune as small natural numbers, for example, 1:2 or 3:4. In this way, the objects mutually stabilize their orbits. If, for example, an object revolves around the Sun at twice the speed of Neptune, it will travel exactly halfway, while Neptune will return to its original position.
The most densely populated part of the Kuiper belt, which includes more than 200 known objects, is in a 2:3 resonance with Neptune. These objects orbit once every 1 1/2 rotations of Neptune and are known as "plutinos" because they include one of the largest Kuiper Belt objects, Pluto. Although the orbits of Neptune and Pluto are very close to each other, the 2:3 resonance will prevent them from colliding. In other, less populated areas, there are resonances of 3:4, 3:5, 4:7 and 2:5.
At its Lagrange points (L4 and L5) - zones of gravitational stability - Neptune holds many Trojan asteroids, as if dragging them along in orbit. Neptune's Trojans are in a 1:1 resonance with him. The Trojans are very stable in their orbits, and therefore the hypothesis of their capture by Neptune's gravitational field is questionable. Most likely, they formed with him.
Internal structure
The internal structure of Neptune resembles internal structure Uranus. The atmosphere makes up approximately 10-20% of the planet's total mass, and the distance from the surface to the end of the atmosphere is 10-20% of the distance from the surface to the core. Near the core, the pressure can reach 10 GPa. Volumetric concentrations of methane, ammonia and water found in the lower layers of the atmosphere
Gradually, this darker and hotter region is compacted into a superheated liquid mantle, where temperatures reach 2000-5000 K. The mass of Neptune's mantle is 10-15 times greater than that of Earth, according to various estimates, and is rich in water, ammonia, methane and other compounds. According to the generally accepted terminology in planetary science, this matter is called icy, even though it is a hot, very dense liquid. This highly conductive liquid is sometimes called an ocean of aqueous ammonia. At a depth of 7000 km, conditions are such that methane decomposes into diamond crystals, which “fall” onto the core. According to one hypothesis, there is an entire ocean of “diamond liquid”. Neptune's core is composed of iron, nickel and silicates and is believed to have a mass 1.2 times that of Earth. The pressure in the center reaches 7 megabars, that is, about 7 million times more than on the surface of the Earth. The temperature in the center may reach 5400 K.
Atmosphere and climate
Hydrogen and helium were found in the upper layers of the atmosphere, which account for 80 and 19%, respectively, at a given altitude. Traces of methane are also observed. Noticeable absorption bands of methane occur at wavelengths above 600 nm in the red and infrared parts of the spectrum. As with Uranus, the absorption of red light by methane is the most important factor, giving Neptune's atmosphere a blue tint, although Neptune's bright azure differs from the more moderate aquamarine color of Uranus. Since the methane content in Neptune's atmosphere is not very different from that in the atmosphere of Uranus, it is assumed that there is also some, as yet unknown, component of the atmosphere that contributes to the formation of the blue color. Neptune's atmosphere is divided into 2 main regions: the lower troposphere, where the temperature decreases with altitude, and the stratosphere, where the temperature, on the contrary, increases with altitude. The boundary between them, the tropopause, is at a pressure level of 0.1 bar. The stratosphere gives way to the thermosphere at a pressure level lower than 10 -4 - 10 -5 microbars. The thermosphere gradually turns into the exosphere. Models of Neptune's troposphere suggest that, depending on altitude, it consists of clouds of varying compositions. Clouds top level are in a pressure zone below one bar, where the temperature promotes methane condensation.
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Methane on Neptune
The false-color image was taken by the Voyager 2 spacecraft using three filters: blue, green and a filter that shows the absorption of light by methane. Thus, regions in the image that are bright white or red contain a higher concentration of methane. All of Neptune is covered in a ubiquitous methane haze in a translucent layer of the planet's atmosphere. At the center of the planet's disk, light passes through the haze and goes deeper into the planet's atmosphere, causing the center to appear less red, and at the edges methane haze scatters sunlight into high altitude, resulting in the formation of a bright red halo. |
| PLANET NEPTUNE |
At pressures between one and five bars, clouds of ammonia and hydrogen sulfide form. At pressures greater than 5 bar, clouds may consist of ammonia, ammonium sulfide, hydrogen sulfide and water. Deeper down, at a pressure of approximately 50 bar, clouds of water ice can exist at temperatures as low as 0 °C. It is also possible that clouds of ammonia and hydrogen sulfide may be found in this area. Neptune's high-altitude clouds were observed by the shadows they cast on the opaque cloud layer below. Prominent among them are cloud bands that “wrap” around the planet at a constant latitude. These peripheral groups have a width of 50-150 km, and they themselves are 50-110 km above the main cloud layer. Study of Neptune's spectrum suggests that its lower stratosphere is hazy due to the condensation of ultraviolet photolysis products of methane, such as ethane and acetylene. Traces of hydrogen cyanide and carbon monoxide.
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High altitude cloud bands on Neptune
The image was taken by the Voyager 2 spacecraft two hours before its closest approach to Neptune. The vertical bright streaks of Neptune's clouds are clearly visible. These clouds were observed at a latitude of 29 degrees north near Neptune's eastern terminator. Clouds cast shadows, meaning they are higher than the underlying opaque cloud layer. Image resolution is 11 km per pixel. The width of the cloud bands is from 50 to 200 km, and the shadows they cast extend for 30-50 km. The height of the clouds is approximately 50 km. |
| PLANET NEPTUNE |
The stratosphere of Neptune is warmer than the stratosphere of Uranus due to more high concentration hydrocarbons. For unknown reasons, the planet’s thermosphere has an anomalously high temperature of about 750 K. For such high temperature the planet is too far from the Sun for it to heat up the thermosphere with ultraviolet radiation. Perhaps this phenomenon is a consequence of atmospheric interaction with ions in the planet’s magnetic field. According to another theory, the basis of the heating mechanism are gravitational waves from the inner regions of the planet, which are dissipated in the atmosphere. The thermosphere contains traces of carbon monoxide and water that entered it, possibly from external sources such as meteorites and dust.
One of the differences between Neptune and Uranus is the level of meteorological activity. Voyager 2, which flew near Uranus in 1986, recorded extremely weak atmospheric activity. In contrast to Uranus, Neptune experienced noticeable weather changes during Voyager 2's 1989 survey.
The weather on Neptune is characterized by an extremely dynamic storm system, with winds reaching near supersonic speeds (about 600 m/s). While tracking the movement of permanent clouds, a change in wind speed was recorded from 20 m/s in the east to 325 m/s in the west. In the upper cloud layer, wind speeds vary from 400 m/s along the equator to 250 m/s at the poles. Most winds on Neptune blow in the direction opposite to the planet's rotation on its axis. General scheme winds shows that at high latitudes the direction of the winds coincides with the direction of rotation of the planet, and at low latitudes it is opposite to it. Differences in the direction of air currents are believed to be a consequence of the "skin effect" rather than any underlying atmospheric processes. The content of methane, ethane and acetylene in the atmosphere in the equator region is tens and hundreds of times higher than the content of these substances in the pole region. This observation can be considered evidence in favor of the existence of upwelling at Neptune's equator and its decrease closer to the poles.
In 2006, it was observed that the upper troposphere of Neptune's south pole was 10 °C warmer than the rest of Neptune, where temperatures average -200 °C. This difference in temperature is enough to allow methane, which is frozen in other areas of Neptune's upper atmosphere, to leak into space at the south pole. This " hot spot“- a consequence of the axial tilt of Neptune, the south pole of which has been facing the Sun for a quarter of the Neptunian year, that is, approximately 40 Earth years. As Neptune slowly moves along its orbit to the opposite side of the Sun, the south pole will gradually go into shadow, and Neptune will substitute the north pole for the Sun. Thus, the release of methane into space will move from the south pole to the north. Due to seasonal changes, cloud bands in Neptune's southern hemisphere have been observed to increase in size and albedo. This trend was noticed back in 1980, and is expected to continue until 2020 with the arrival of a new season on Neptune. The seasons change every 40 years.
In 1989, NASA's Voyager 2 discovered the Great Dark Spot, a persistent anticyclonic storm measuring 13,000 x 6,600 km. This atmospheric storm resembled Jupiter's Great Red Spot, but on November 2, 1994, the Hubble Space Telescope did not find it in its original location. Instead, a new similar formation was discovered in the northern hemisphere of the planet. Scooter is another storm found south of Bolshoy dark spot. Its name is a consequence of the fact that several months before Voyager 2's approach to Neptune, it was clear that this group of clouds was moving much faster than the Great Dark Spot. Subsequent images revealed groups of clouds even faster than the scooter.
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Big dark spot
The photo on the left was taken with Voyager 2's narrow-angle camera using a green and orange filter, from a distance of 4.4 million miles from Neptune, 4 days and 20 hours before closest approach to the planet. The Great Dark Spot and its smaller companion to the west, the Lesser Dark Spot, are clearly visible. The series of images on the right shows changes in the Great Dark Spot over 4.5 days during the approach of the Voyager 2 spacecraft, the shooting interval was 18 hours. The large dark spot is located at a latitude of 20 degrees south and extends up to 30 degrees in longitude. The top image in the series was taken at a distance of 17 million km from the planet, the bottom - 10 million km. A series of images showed that the storm was changing over time. In particular, in the west, at the beginning of the survey, a dark plume stretched behind the BTP, which then was drawn into the main area of the storm, leaving behind a series of small dark spots - “beads”. The large bright cloud at the southern border of the BTP is a more or less constant companion to the formation. The apparent movement of small clouds at the periphery suggests counterclockwise rotation of the FTP. |
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The Minor Dark Spot, the second most intense storm observed during Voyager 2's approach to the planet in 1989, is located even further south. Initially it appeared completely dark, but as it got closer, the bright center of the Lesser Dark Spot became more visible, as can be seen in most clear, high-resolution photographs. Neptune's "dark spots" are thought to originate in the troposphere at lower altitudes than the brighter, more visible clouds. Thus, they appear to be holes in the cloud tops, as they open up gaps that allow one to see through darker, deeper cloud layers.
Because these storms are persistent and can persist for months, they are thought to have a vortex structure. Often associated with dark spots are brighter, persistent clouds of methane that form at the tropopause. The persistence of the accompanying clouds shows that some former "dark spots" may continue to exist as a cyclone, even though they lose their dark color. Dark spots can dissipate if they move too close to the equator or through some other as-yet-unknown mechanism
The more varied weather on Neptune, compared to Uranus, is believed to be a consequence of higher internal temperatures. At the same time, Neptune is one and a half times farther from the Sun than Uranus, and receives only 40% of the amount of sunlight that Uranus receives. The surface temperatures of these two planets are approximately equal. The upper troposphere of Neptune reaches a very low temperature of -221.4 °C. At a depth where the pressure is 1 bar, the temperature reaches -201.15 °C. The gases go deeper, but the temperature steadily rises. As with Uranus, the heating mechanism is unknown, but the discrepancy is large: Uranus emits 1.1 times more energy than it receives from the Sun. Neptune emits 2.61 times more than it receives, it internal source heat adds 161% to the energy received from the Sun. Although Neptune is the farthest planet from the Sun, its internal energy is sufficient to generate the fastest winds in the world. solar system.
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New dark spot
The Hubble Space Telescope has discovered a new large dark spot located in Neptune's northern hemisphere. Neptune's tilt and its current position make it almost impossible to see more details now; as a result, the spot in the image is located near the planet's limb. The new spot replicates a similar storm in the southern hemisphere that was discovered by Voyager 2 in 1989. In 1994, images from the Hubble telescope showed that the sunspot in the southern hemisphere had disappeared. Like its predecessor, the new storm is surrounded by clouds at the edge. These clouds form when gas from lower regions rises and then cools to form methane ice crystals. |
| PLANET NEPTUNE |
Several possible explanations have been proposed, including radiogenic heating by the planet's core (similar to the heating of the Earth by radioactive potassium-40), the dissociation of methane into other chain hydrocarbons in Neptune's atmosphere, and convection in the lower atmosphere, which leads to the braking of gravitational waves above the tropopause.
- Neptune is the eighth and farthest planet from the Sun. The ice giant is located at a distance of 4.5 billion km, which is 30.07 AU.
- A day on Neptune (a full revolution around its axis) is 15 hours 58 minutes.
- The period of revolution around the Sun (Neptunian year) lasts about 165 Earth years.
- Neptune's surface is covered by a huge deep ocean of water and liquefied gases, including methane. Neptune is blue, like our Earth. This is the color of methane, which absorbs the red part of the sunlight spectrum and reflects the blue.
- The planet's atmosphere consists of hydrogen with a small admixture of helium and methane. The temperature of the upper edge of the clouds is -210 °C.
- Despite the fact that Neptune is the farthest planet from the Sun, its internal energy is sufficient to have the fastest winds in the solar system. Neptune's atmosphere has the strongest winds among the planets in the solar system; according to some estimates, their speeds can reach 2100 km/h
- There are 14 satellites orbiting Neptune. which were named after various gods and nymphs of the sea in Greek mythology. The largest of them, Triton, has a diameter of 2700 km and rotates in the opposite direction of rotation of the other satellites of Neptune.
- Neptune has 6 rings.
- There is no life on Neptune as we know it.
- Neptune was the last planet, which Voyager 2 visited on its 12-year journey through the Solar System. Launched in 1977, Voyager 2 passed within 5,000 km of Neptune's surface in 1989. The earth was more than 4 billion km from the event site; The radio signal with information traveled to Earth for more than 4 hours.
Neptune is the eighth planet from the Sun and the last known planet. Although it is the third most massive planet, it is only the fourth in terms of diameter. Thanks to its blue color, Neptune received the name of the Roman god of the sea.
As you complete certain scientific discoveries Scientists often have disputes about which theory is trustworthy. The discovery of Neptune is a clear example such disagreements.
After the planet was discovered in 1781, astronomers noticed that its orbit was subject to significant fluctuations, which in principle should not exist. As a justification for this incomprehensible phenomenon, a hypothesis was proposed about the existence of a planet, the gravitational field of which causes the orbital deviations of Uranus.
However, the first scientific works related to the existence of Neptune appeared only in 1845-1846, when the English astronomer John Couch Adams published his calculations about the position of this then unknown planet. However, despite the fact that he submitted his work to the Royal Scientific Society (the leading English research organization), his work did not attract the expected interest. It was only a year later that French astronomer Jean Joseph Le Verrier also presented calculations that were strikingly similar to Adams's. As a result independent assessments scientific work two scientists, the scientific community finally agreed with their conclusions and began searching for a planet in the area of the sky that Adams and Le Verrier's research had pointed to. The planet itself was discovered on September 23, 1846 by the German astronomer Johann Gall.
Before the flyby of the Voyager 2 spacecraft in 1989, humanity had very little information about the planet Neptune. The mission provided data on Neptune's rings, number of moons, atmosphere and rotation. Voyager 2 also revealed significant features of Neptune's moon Triton. To date, the world's space agencies are not planning any missions to this planet.
The upper layers of Neptune's atmosphere are 80% hydrogen (H2), 19% helium and small amounts of methane. Like Uranus, Neptune's blue color is due to its atmospheric methane, which absorbs light at a wavelength that corresponds to the color red. However, unlike Uranus, Neptune has a deeper blue, which indicates the presence in the atmosphere of Neptune of components that are not present in the atmosphere of Uranus.
Weather conditions on Neptune have two distinctive features. First, as was noticed during the flyby of the Voyager 2 mission, these are the so-called dark spots. These storms are comparable in scale to Jupiter's Great Red Spot, but differ greatly in their duration. The storm known as the Great Red Spot has been going on for centuries, but Neptune's dark spots can last no more than a few years. Information about this was confirmed thanks to observations from the Hubble Space Telescope, which was sent to the planet just four years after Voyager 2 made its flyby.
The second notable weather phenomenon on the planet is rapidly moving storms white, which were called “Scooter”. As observations have shown, this is a unique type of storm system, the size of which is much smaller than the size of dark spots, and its lifespan is even shorter.
Like the atmospheres of other gas giants, Neptune's atmosphere is divided into latitudinal bands. The wind speed in some of these bands reaches almost 600 m/s, that is, the planet’s winds can be called the fastest in the solar system.
Structure of Neptune
Neptune's axial tilt is 28.3°, which is relatively close to Earth's 23.5°. Considering the planet’s significant distance from the Sun, Neptune’s presence of seasons comparable to those on Earth is a rather surprising and not fully understood phenomenon for scientists.
Moons and rings of Neptune
Today it is known that Neptune has thirteen satellites. Of these thirteen, only one is large and spherical in shape. There is a scientific theory according to which Triton, the largest of Neptune's moons, is a dwarf planet that was captured by the gravitational field and therefore its natural origin remains in question. Evidence for this theory comes from Triton's retrograde orbit - the moon rotates in the opposite direction to Neptune. Additionally, with a recorded surface temperature of -235°C, Triton is the coldest known object in the Solar System.
Neptune is believed to have three main rings: Adams, Le Verrier and Halle. This ring system is much fainter than those of other gas giants. The planet's ring system is so dim that for some time the rings were thought to be defective. However, images transmitted by Voyager 2 showed that this is in fact not the case and the rings completely encircle the planet.
It takes Neptune 164.8 Earth years to complete its orbit around the Sun. July 11, 2011 marked the completion of the planet's first full revolution since its discovery in 1846.
Neptune was discovered by Jean Joseph Le Verrier. The planet remained unknown to ancient civilizations due to the fact that it was not visible from Earth with the naked eye. The planet was originally named Le Verrier, in honor of its discoverer. But the scientific community quickly abandoned this name and the name Neptune was chosen.
The planet was named Neptune after the ancient Roman god of the sea.
Neptune has the second highest gravity in the solar system, second only to Jupiter.
Neptune's largest moon is called Triton, and was discovered 17 days after Neptune itself was discovered.
In Neptune's atmosphere you can see a storm similar to Jupiter's Great Red Spot. This storm has a volume comparable to that of the Earth and is also known as the Great Dark Spot.
