Neptune is the eighth planet orbiting the sun and the fourth largest celestial body (in diameter) in the solar system. Neptune is smaller in diameter than Uranus, but more massive.
Orbit: 4,504,000,000 kilometers from the sun (30.06 astronomical units)
Planet diameter: 49,532 kilometers (equator)
Mass: 1.0247e26 kg
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In ancient Roman mythology, Neptune (ancient Greek mythology: Poseidon) represents the god of the sea.
After Uranus was discovered, it was noticed that its orbit was not consistent with that predicted from Newton's theory. Therefore, scientists predict that there is another distant planet that affects Uranus's orbit. Neptune was first observed by Galle and d'Arrest on September 23, 1846, very close to where Adams and Le Verrier had independently predicted based on their observed positions of Jupiter, Saturn, and Uranus. An international dispute arose between Britain and France over who discovered Neptune first and who had the right to name it (however, there was no apparent personal dispute between Adams and Le Verrier); the discovery of Neptune was now *** Credit goes to both of them. Later observations showed that the orbit calculated by Adams and Le Verrier deviated considerably from Neptune's true orbit. If the search for Neptune had been carried out a few years earlier or later, people would not have been able to find it at or near where they predicted it would be.
Only one spacecraft, Voyager 2, visited Neptune on August 25, 1989. Almost everything we know about Neptune comes from this brief encounter.
Because Pluto's orbit is extremely weird, it sometimes crosses the orbit of Neptune. Since 1979, Neptune has become the most distant planet from the sun. In 1999, Pluto will become the most distant planet again. .
The composition of Neptune is very similar to that of Uranus: various "ices" and rocks containing 15% hydrogen and a small amount of helium. Neptune is similar to Uranus but different from Saturn and Jupiter. It may have obvious internal geological layering, but it is more or less consistent in composition. But Neptune most likely has a small, rocky core (with a mass similar to Earth). Its atmosphere is mostly composed of hydrogen and helium. There is also a small amount of methane.
Neptune’s blue color is caused by methane in the atmosphere absorbing red light from sunlight.
As a typical gas planet, Neptune is roaring with large storms or cyclones distributed in strips. The storms on Neptune are the fastest in the solar system, with speeds reaching 2,000 kilometers per hour.
Like Saturn and Jupiter, Neptune has an internal heat source - the energy it radiates is more than twice the solar energy it absorbs.
During Voyager 2’s visit to Neptune, the most obvious feature on the planet was the Great Dark Spot in the southern hemisphere. The Dark Spot is about half the size of Jupiter's Great Red Spot (and similar in diameter to Earth), and Neptune's fast winds blow the Great Dark Spot westward at speeds of 300 meters per second (700 mph). Voyager 2 also discovered a smaller black spot in the southern hemisphere - an irregular small cloud of white smoke that flies around the planet at a speed of about 16 hours. It is now known to be "The Scooter". It may be a plume rising from lower in the atmosphere, but its true nature remains a mystery.
However, observations of Neptune by the Hubble Telescope in 1994 showed that the Great Dark Spot had disappeared! It may simply dissipate, or it may be temporarily obscured by other parts of the atmosphere. A few months later the Hubble Space Telescope discovered a new dark spot in Neptune's northern hemisphere. This suggests that Neptune's atmosphere changes frequently, perhaps caused by subtle changes in temperature differences at the top and bottom of the clouds.
Neptune also has rings. On Earth, only dim, fuzzy arcs can be observed, rather than complete rings. But Voyager 2 images show these arcs to be rings made entirely of bright patches. One of the rings appears to have a strange spiral structure.
Like Uranus and Jupiter, Neptune's rings are very dim, but their internal structure is still unknown.
People have named Neptune’s rings: the outermost one is Adams (it includes three obvious arcs, now named Liberty, Equality and Fraternity), followed by an unnamed one The package has the arc of the satellite Galatea, then Leverrier (its outward extensions are called Lassell and Arago), and the innermost dim but broad one called Galle.
Neptune's magnetic field is the same as Uranus's, and its position is very strange. This is probably caused by the movement of conductive material (probably water) in the middle layer of the planet's crust.
Neptune can be seen through binoculars (assuming you really know where to look), but if you want to see all of the planet and not just a small disk, you'll need one Large astronomical telescope. Mike Harvey's planet-finding chart points out the position of Neptune (and the positions of other planets) in the sky at this time, and is then customized in more detail by the astronomical program Starry Night.
Satellites of Neptune
Neptune has 8 known satellites: 7 small moons and Triton. Among them, Triton is the most massive satellite in the solar system.
Satellite distance (km) Radius (km) Discoverer Discovery date
Triton 48000 29 Voyager 2 1989
Triton 50000 40 Voyager 2 1989
Triton 53000 74 Voyager 2 1989
Triton 62000 79 Voyager 2 1989
Triton 74000 96 Voyager 2 1989
Triton 118000 209 Voyager 2 1989
Triton 355000 1350 2.14e22 Lassell 1846
Triton 5509000 170 Kuiper 1949
Neptune’s halo
Halo distance (km) Width (km) Also known as
Diffuse 41900 15 1989N3R, Galle
Inner 53200 15 1989N2R, Le Verrier
Plateau 53200 5800 1989N4R, Lassell, Arago
Main 62930 < 50 1989N1R, Adams
(distance is the center of Neptune to the inner ends of the rings)
Unknown point
Neptune's magnetic field is deviated from the center of the earth and forms a large angle with the axis of rotation. How is such a weird magnetic field formed?
What is the reason why Neptune and Uranus are relatively lacking in hydrogen and helium?
Although Neptune is very far away from the sun and its internal heat source is relatively weak, why are the winds on the planet's surface so strong?
What happened to the "Great Dark Spot"?
Can we design a practical mission around Neptune that is cheap enough?
Mysterious light blue - Neptune
Neptune is one of the far-solar planets. It is the eighth planet arranged from near to far according to the average distance from the sun.
Its brightness is only magnitude 7.85, and it can only be seen with an astronomical telescope. Because of its glowing light blue light, Westerners call it "Neptune" after the sea god in Roman mythology. In Chinese, it is translated as Neptune.
The equatorial radius of Neptune is 24,750 kilometers, which is 3.88 times the equatorial radius of the Earth. Neptune is oblate spherical, its volume is 57 times the volume of the Earth, its mass is 17.22 times the mass of the Earth, and its average density is per day. Cubic centimeters are 1.66 grams. Neptune is the third largest planet in the solar system, only smaller than Jupiter and Saturn.
It is now believed that Neptune has a core with a mass similar to that of the Earth. The core is made of rock and has a temperature of about 2000 to 3000 degrees Celsius. Outside the core is an ice envelope with a larger mass, and outside it is A dense atmosphere, which mainly contains hydrogen, as well as gases such as methane and ammonia. Neptune is a world with howling winds and flying clouds. There are many turbulent and chaotic cyclones rolling in the atmosphere.
Neptune’s rotation period is about 22 hours. The intersection angle between its equatorial plane and its orbital plane is 28 degrees and 48 minutes. Neptune’s orbit around the sun is very close to a perfect circle. The angle between the orbital plane and the ecliptic plane is The angle is very small, only 1 degree 8 minutes. It revolves at an average speed of 5.43 kilometers per second. It takes about 164.8 years to go around the sun. From its discovery in 1846 to now, it has not completed the entire journey.
In the four seasons of Neptune, the temperature difference between winter and summer is very small, not as significant as that on Earth. Because Neptune is too far away from the sun (about 450 million kilometers, which is 30 times the distance between the earth and the sun), the solar radiation received per unit area on its surface is only 1/900 of that on the earth, and the solar intensity is only equivalent to less than one The intensity of the light emitted by a hundred-watt light bulb is 100 meters away, so its surface temperature is very low, usually below minus 200 degrees Celsius.
So far, Neptune has been discovered to have 8 satellites.
Uranus is the seventh planet from the sun in the solar system and the third largest planet in the solar system in terms of diameter. Uranus is larger than Neptune, but its mass is smaller.
Orbit: 2,870,990,000 kilometers from the sun (19.218 astronomical units)
Planet diameter: 51,118 kilometers (equator)
Mass: 8.683e25 kg
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Be careful when pronouncing the English name of Uranus, otherwise it may put you in an embarrassing situation. Uranus should be pronounced "YOOR a nus", not "your anus" (your anus) or "urine us" (pee on us).
Uranus is the god of the universe in ancient Greek mythology and the earliest supreme god. He was the son and consort of Gaia and the father of Cronus (Saturn), the Cyclops, and the Titans (predecessors of the Olympian gods).
Uranus was discovered by William Herschel on March 13, 1781, after a systematic search through telescopes. It was the first planet discovered in modern times. In fact, it has been observed many times, but was mistaken for another star (John Flamsteed had observed its existence as early as 1690, but classified it as 34 Tauri at the time). Herschel named it "the Georgium Sidus" (Georgia Planet) in honor of his sponsor, the notorious British king to Americans: George III; others called Uranus "Herschel" Ear". Since the names of other planets were taken from Greek mythology, Bode first proposed calling it "Uranus" (Uranus) for consistency, but it was not widely used until 1850.
Only one interplanetary probe has ever visited Uranus, which was completed by Voyager 2 on January 24, 1986.
Most planets always rotate around an axis that is almost perpendicular to the ecliptic plane, but Uranus's axis is almost parallel to the ecliptic plane. During the time of the Voyager 2 exploration, Uranus's south pole received almost direct sunlight. This peculiar fact indicates that Uranus' poles receive more energy from the Sun than its equatorial regions. However, Uranus's equatorial regions are still hotter than their polar regions. The reason for this is unknown.
And it either rotates forward with an axis angle greater than 90 degrees, or rotates reversely with an inclination angle less than 90 degrees. The problem is that you have to draw the line somewhere, because for example there is some controversy as to whether Venus is actually rotating in a reverse direction (as opposed to a forward rotation with an inclination of nearly 180 degrees).
Uranus is basically composed of rock and various ices. It contains only 15% hydrogen and some helium (less compared to Jupiter and Saturn, which are mostly composed of hydrogen) . Uranus and Neptune are in many ways similar to the cores of Jupiter and Saturn, minus their giant shells of liquid metallic hydrogen. Although Uranus's core is not made of rock like Jupiter and Saturn, their material distribution is almost the same.
Uranus' atmosphere contains approximately 83% hydrogen, 15% helium and 2% methane.
Like all other gaseous planets, Uranus has ribbons of clouds that move rapidly around it. But they are so faint that they can only be seen in processed images from Voyager 2 (right). Recent Hubble observations (left) show the stripes to be larger and more pronounced. It is speculated that this difference is mainly due to the effect of seasons (direct sunlight to a low-latitude region of Uranus may cause obvious day and night effects).
The blue color of Uranus is the result of methane in its outer atmosphere absorbing red light. There may be ribbons there like those on Jupiter, but they are obscured by the blanket of methane.
Like all other gaseous planets, Uranus has rings. They are faint like Jupiter's rings, but like Saturn's rings are composed of rather large particles up to 10 meters in diameter and fine dust. Uranus has 11 known rings, but all are very dim; the brightest one is called the Epsilon ring. The rings of Uranus were the first to be discovered after the discovery of Saturn. This discovery was considered very important. From this we know that rings are a universal feature of planets, not just unique to Saturn.
Voyager 2 discovered 10 small satellites after the 5 known large satellites. It appears that there are also smaller moons within the rings.
Speaking of the issue of Uranus's axis, it is also worth mentioning that its magnetic field is also very strange. It is not at the center of the planet, but is tilted by nearly 60 degrees. This may be caused by motion deeper within Uranus.
Sometimes in a clear night sky, the blurry Uranus can just be seen with the naked eye, but if you know its location, it is very easy to observe through binoculars. A small disk can be seen through a small telescope. Mike Harvey's planet-finding chart shows the location of Uranus and other planets in the sky. More and more details, and better and better diagrams will be discovered and completed by astronomical programs like Brilliant Galaxy.
Satellites of Uranus
Uranus has 15 named satellites and 2 discovered but unnamed satellites.
Unlike other celestial bodies in the solar system, Uranus' moons are not named after characters from ancient mythology, but instead after characters in the works of Shakespeare and the Pope.
They are naturally divided into two groups: the 10 very faint small satellites close to Uranus discovered by Voyager 2 and the 5 large satellites in the outer layers. (Image on the right)
They both have a circular orbit around Uranus' equator (and therefore a large angle relative to the equatorial plane).
Satellite distance
(kilometer) Radius
(kilometer) Mass
(kilogram) Discoverer Discovery date
Titus 50000 13 ? Voyager 2 1986
Tips 54000 16 ? Voyager 2 1986
Tips 59000 22 ? Voyager 2 1986
Voyager 9 62000 33 ? Voyager 2 1986
Voyager 10 63000 29 ? Voyager 2 1986
Voyager 11 64000 42 ? Voyager 2 1986
Voyager 12 66000 55 ? Voyager 2 1986
Voyager 2 1986 70000 27 ? Voyager 2 1986
14 75000 34 ? Voyager 2 1986
18 75000 20 ? Karkoschka 1999
15 86000 77 ? Voyager 2 1985
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Kuiper 130000 236 6.30e19 Kuiper 1948
Kuiper 191000 579 1.27e21 Lassell 1851
Kuiper 266000 585 1.27e21 Lassell 1851
Titus 436000 789 3.49e21 Herschel 1787
Titus 583000 761 3.03e21 Herschel 1787
Titus 7200000 30 ? Gladman 1997
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12200000 60 ? Gladman
1997
Uranus’s Halo
Halo Distance
(km) Width
(km)
1986U2R 38000 2,500
6 41840 1-3
5 42230 2-3
4 42580 2-3
Alpha 44720 7-12
Beta 45670 7-12
Eta 47190 0 -2
Gamma 47630 1-4
Delta 48290 3-9
1986U1R 50020 1-2
Epsilon 51140 20-100
(Distance refers to the length from the center of Uranus to the inner edge of the ring)
Unknown point
Why does Uranus not radiate like other gaseous planets? More energy than you get from the sun? Is it cold inside?
Why is its axis so unusually tilted? Was it caused by a violent collision?
Why do Uranus and Neptune have much less hydrogen and helium than Jupiter and Saturn? Is it just because they are smaller? Or is it because it is farther from the sun?
Lying in orbit - Uranus
Uranus is a far-solar planet, the seventh in order from closest to far from the sun. In the West, Uranus is called "Uranus", and he is the first god to rule the entire universe. He combined with the earth mother Gaia and gave birth to the later gods. It was he who worked hard to plan the chaotic universe into harmony and order. In Chinese, people translate this star name as "Uranus".
Uranus is a blue-green ball. Its surface has a whitish blue-green glow and stripes that are not parallel to the equator. This is probably due to the atmospheric flow caused by the fast rotation speed. Uranus has an equatorial radius of approximately 25,900 kilometers and its volume is 65 times that of Earth. The mass is approximately 14.63 times that of Earth. Uranus is less dense, with an average density of 1.24 grams per cubic centimeter.
The main components of Uranus's atmosphere are hydrogen, helium and methane.
The orbit of Uranus is an ellipse with an orbital radius of 2.9 billion kilometers. It orbits the sun at an average speed of 6.81 kilometers per second. It takes 84 years to complete one revolution, and its rotation period is much shorter, only is 15.5 hours. In the solar system, all planets basically follow a motion where the rotation axis is nearly perpendicular to the orbital plane. The only exception is Uranus. Its rotation axis is almost parallel to the orbital plane. The intersection angle between the equatorial plane and the orbital plane is 97 degrees and 55 minutes. , that is to say, it is almost "lying" and moving around the sun. So some people call Uranus "an upside-down planetary world."
The alternation of day and night and the changes of the seasons on Uranus are also very strange and complex. The sun takes turns shining on the North Pole, equator, south pole, and equator. Therefore, it takes 42 years for each day and night to change in most areas of Uranus. Whichever pole the sun shines on is summer. The sun never sets and there is no night. The pole facing away from the sun is in the cold winter shrouded in long dark nights. Only between 8 degrees north and south latitude near the equator of Uranus, there are day and night changes caused by the rotation period.
Uranus, like Saturn, also has beautiful rings, and it is also a complex ring system. Its halo is composed of 20 thin rings, each ring is of different colors, colorful and extremely beautiful. This discovery in the 1970s broke the traditional understanding that Saturn is the only planet in the solar system with rings. Uranus has 15 satellites, almost all of which orbit Uranus on the equatorial plane close to Uranus.
Uranus's short file
The upside-down planetary world
Uranus orbits the sun outside of Saturn, and it takes 84.01 Earth years to complete one revolution. The way Uranus rotates is very strange, like a naughty child lying on the ground and rolling around. Uranus lies sideways in its orbit, rolling around the sun. The result of this movement of Uranus is that the spring and autumn seasons on Uranus have a rapid alternation between day and night, with the sun rising approximately every 16.8 hours. The two seasons of winter, summer and spring and autumn are completely different. When the southern hemisphere of Uranus faces the sun, the southern hemisphere is in summer. During this period, the sun always circles over the southern hemisphere and never sets. It is always daytime in the Southern Hemisphere throughout the summer. At this time, the northern hemisphere facing away from the sun is in winter, and the entire winter lasts for a long night of 21 Earth years. No wonder some people call Uranus "an upside-down planetary world."
Satellites of Uranus
Before 1977, we only knew that Uranus had 5 satellites. Almost all of these 5 satellites orbited Uranus on the equatorial plane close to Uranus. Because Uranus's rotation axis is tilted at an angle of 98°, these five satellites have become retrograde satellites. Among them, Titan and Titan are larger, with diameters of 1,000 kilometers and 1,630 kilometers respectively. The remaining three are smaller. The smallest, Titan, was discovered by American astronomer Kuiper in 1948, with a diameter of 484 kilometers. The terrain of Tianwei is complex, with peaks up to 24 kilometers high, pitted holes and several linear grooves. Its cause is still a mystery.
In 1986, the Voyager 2 probe visited the planet and discovered 10 new satellites, tripling its number of satellites to a total of 15. The newly discovered satellites are They are very close to Uranus, but they are relatively small, with diameters ranging from 20 to 100 kilometers. The largest one has a diameter of 160 kilometers. This satellite is called 1985UI. Only this satellite was discovered by Voyager 2 on its journey to Uranus.
The face of Uranus has only been slightly revealed, and new mysteries will continue to arise. If we want to have a deeper understanding of the mysterious Uranus, we must rely on the long-term and unremitting efforts of astronomers.
An unexpected discovery
It has long been known to everyone that Saturn has beautiful and peculiar rings, and the rings seem to have become Saturn's
"patent". It was not until the 1970s that this monopoly was broken.
On March 10, 1977, during a celestial observation of Uranus occulting a star, Uranus moved slowly in the sky and passed behind a faint star numbered SAO158687 in the constellation Libra. A rare occultation occurred. Starry sky phenomenon. Observatories in China, the United States, Australia, India and South Africa all seized this rare opportunity to observe.
The phenomenon of dimming and brightening appeared 5 times before the occultation and 5 times after the occultation. After analysis by astronomers, it was confirmed that Uranus also has rings, which are 9 thin rings with a width of about 100,000 kilometers.
On January 24, 1986, when the Voyager 2 probe flew by Uranus at a speed of 72,000 kilometers per hour, it discovered 11 more rings on Uranus, correcting the understanding of 9 rings. Uranus has 20 rings, and different rings have different colors, adding new luster to this distant planet.
Neptune also has radiation belts and auroras similar to those seen at the Earth's North and South Poles. It occurs every 16 hours and 3 minutes to 16 hours and 5 minutes, indicating that Neptune also has a magnetic field. The inclination angle between Neptune's magnetic field and its rotation axis is about 50°, and its magnetosphere is mainly composed of hydrogen ions, helium ions and ammonia ions.
Discovery on the tip of the pen
Since the discovery of Uranus in 1781, people have found that Uranus always does not follow the "rules" and always sways this way and that in its orbit around the sun. has puzzled many astronomers: perhaps there is a large planet outside Uranus, and its existence causes Uranus to behave abnormally! In the 19th century, many astronomers devoted themselves to the popular search for this "exoplanet".
At that time, two young men, the British Adams and the French Le Verrier, carried out calculation work for a full 2 ??years without knowing each other. In 1845, Adams first calculated the orbit of the "extraterrestrial planet" , however, the Greenwich Observatory shelved his paper and missed the opportunity to find new stars first. On September 18, 1846, Le Verrier sent the calculation results to Berlin, but they were taken seriously. Galle of the Berlin Observatory lost no time in searching for this "extraplanet" and finally discovered this new planet near the location pointed by Le Verrier. This is the eighth planet in the solar system family - Neptune.
The discovery of Neptune under the tip of the pen has pushed the territory of the solar system outward again, reaching a distance of 4.5 billion kilometers. At the same time, it has provided the best evidence for the Copernican theory and Newtonian mechanics, becoming a scientific A popular story in history.
Neptune
Neptune in large astronomical telescopes shows a light blue round surface. People naturally think of the blue sea, so Westerners use the name in Roman mythology It is called after Neptune, the god of the sea, which is translated as Neptune in Chinese.
Brothers of Uranus
Neptune’s orbit around the sun has a radius of 4.5 billion kilometers, which is 30 times that of the earth from the sun. It takes 165 years to complete one revolution. From its discovery in 1846 to today, Neptune has not yet completed a complete journey.
Neptune has a diameter of 49,400 kilometers, similar to Uranus, and its mass is slightly larger than Uranus. Therefore, Neptune's internal structure is very similar to that of Uranus, so it is said to be Uranus's twin brother.
Neptune’s surface is also surrounded by a thick atmosphere, which contains gases such as hydrogen, methane and ammonia. Because Neptune is far away from the sun, the effective surface temperature is -230°C. However, in the infrared band, Neptune's radiation energy exceeds the solar energy it absorbs, which indicates that Neptune may also have internal local energy. From the photos sent back by Voyager 2 when it inspected Neptune in August 1989, it was found that there is a large oval-shaped black spot, two dark spots and three bright spots on Neptune. The black spot is about 12,800 kilometers in diameter and looks like a big eye, rotating counterclockwise about once every 10 days. This big dark spot is actually a cyclone, which is a high-pressure area in Neptune's atmosphere. There are some cirrus-like clouds about 50 kilometers above it. Analysis shows that Neptune's atmosphere contains high concentrations of methane and hydrogen sulfide.
The internal structures of Uranus and Neptune are neither rich in silicon and iron like the terrestrial planets, nor rich in hydrogen and helium like the giant planets. They are basically composed of hydrides such as water, methane, and ammonia. Composition; and silicates, iron, hydrogen and helium are only minor components. This means that although Uranus and Neptune are liquid planets like the giant planets, their chemical composition is no longer the original nebula material.
It is now believed that hydrogen is still the main component in the atmospheres of Uranus and Neptune, and their internal structure is divided into three layers: a hydrogen-rich atmosphere with a mass of 1 to 2 Earth masses; composed of methane, ammonia and water The liquid mantle has a mass of about 10 times the mass of the Earth; the rock-ice core has a mass of about 3 times the mass of the Earth.
According to ground observations, Uranus and Neptune also have magnetospheres. To this end, the "Voyager 2" detection project has set up the detection project of the magnetosphere of Uranus and Neptune. "Voyager 2" detected radio signals and charged particle streams emitted by Uranus before reaching its closest point. It has been determined that Uranus also has a magnetosphere structure, and its magnetosphere is mainly composed of plasma composed of protons and electrons. The magnetosphere extends to an altitude of at least 590,000 kilometers on the side facing the sun, and its magnetotail extends to 6 million kilometers. Uranus also has radiation belts similar to Earth's Van Allen Belts.
On August 24, 1989, Voyager 2 arrived in the near region of Neptune and conducted various explorations of Neptune. Observational data shows us a "picture" of Neptune. Neptune is a blue-green planet with a very active atmosphere, clouds in all layers flowing at high speed, and storms emerging one after another. There are two dark spots and three bright spots in the atmosphere. One of the large dark spots reaches 12,000 kilometers in the east-west direction and 8,000 kilometers in the north-south direction. It is located at 21° south latitude in the southern hemisphere of Neptune. Like the Great Red Spot of Jupiter, it is an air mass moving in a counterclockwise direction. The southern part of the Great Dark Spot is accompanied by bright white spots. Voyager 2 also discovered six new satellites of Neptune, bringing the total number of Neptune's satellites to eight. Discovered that Neptune has 5 rings. To date, Jupiter, Saturn, Uranus and Neptune all have rings. They are both Jupiter-like planets. This has injected new vitality into the study of the origin and evolution of the solar system.
Exploring Neptune
On August 24, 1989, after 12 years of long journey, the Voyager 2 probe arrived at the last stop of the journey - Neptune as scheduled. We conducted detailed scientific investigations and sent back a large number of clear photos and data to astronomers, making our understanding of Neptune no longer as hazy as looking at flowers in the fog.
The photos taken by Voyager 2 when it flew close to Neptune showed people that Neptune is a lively world with howling winds and flying clouds. There are many turbulent and chaotic cyclones rolling in the atmosphere. There is a striking large black spot in the southern hemisphere of Neptune. Its shape, relative position and size ratio of the planet are actually similar to the Great Red Spot of Jupiter. Astronomers believe it is also a large cyclone, a thrilling storm zone.
Before Voyager 2 investigated Neptune, it was generally believed that Neptune had only two satellites, Triton and Triton. Six more satellites were discovered after close-in detection, bringing the total number of Neptune's satellites to eight. The newly discovered satellites are tentatively named 1989N1~1989N6. 1989N6 is the closest to Neptune, followed by 1989N5, 1989N3, 1989N4, 1989N2, 1989N1, Triton and Triton.
Voyager 2 focused on investigating Triton. As it approaches Triton from the south, a dazzling white world appears in front of the camera. Triton's polar cap made of frozen nitrogen covers most of the southern hemisphere. The surface temperature of Triton is only about -310°C. Scientists speculate that it is a celestial body made of a mixture of rock and ice. The probe discovered that a cryovolcano on Triton is erupting, ejecting white clumps of ice and snow and yellow icy nitrogen particles. Due to Triton's low gravity, this eruption can reach a height of 32 kilometers, which is four times the height of Mount Everest. To date, Triton is the third body in the solar system that has been discovered to have active volcanoes. Voyager 2 discovered that Neptune has 5 rings, 3 of which are relatively blurry and may be composed of Neptune fragments. The two outer rings are brighter and neater than the inner ring. Only a few arcs of the outermost ring are particularly bright. After careful observation, it was discovered that there were 7 to 8 ice cubes embedded in the ring (the largest diameter was about 10 to 20 kilometers), and the others were small ice crystals and gravel.
As the Voyager 2 probe flew into space around Neptune, its magnetometer measured Neptune's magnetic field and magnetosphere. It was found that Neptune's magnetic poles are 50° deviated from Neptune's north and south poles. Before that, astronomers had always regarded Uranus's eccentric magnetic field as an anomaly. Now that Neptune is the same, things are not that simple.
How to explain the magnetic fields of these two planets has become a difficult problem for scientists.
Pluto
Among the nine planets, Pluto is the planet with the farthest average distance from the sun and the smallest mass. It stumbles forward in the cold and dark space 5.9 billion kilometers away from the sun. This situation is very similar to Pluto, the king of Hades who lived in the gloomy underground palace in Roman mythology, so it is called Pluto.
Pluto was the last planet discovered.
In the search for Pluto, the most active person was American astronomer Lowell. This astronomer, who is an astronomy enthusiast, has spent more than ten years of hard work from calculating the position of this unknown planet in detail to carefully searching for it with a telescope. His sudden death on November 16, 1916 interrupted the work of discovering overseas planets for 13 years.
In 1925, Lovell's brother generously donated a large field of view 32.5 cm photographic telescope, which has very good performance and provides excellent conditions for continuing to search for new planets. 1929, Lowell Observatory