Orbits of celestial bodies in the

The path is nearly circular, but the orbits of many comets, asteroids and Kuiper Belt objects are highly elliptical.

In such a vast space, there are many ways to represent the distance of each orbit in the . In fact, the farther away from the sun, the further away from the previous one will be, with only a few exceptions. For example, Venus is about 0.33 astronomical units outside Mercury, while Saturn is 4.3 astronomical units and Neptune is 10.5 astronomical units outside Uranus. Some relationships have attempted to explain the interaction between these orbital distance changes.

According to the distance to the sun, the order of planets is Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune (Mercury, Venus, Earth and Mars closer to the sun are called Earth-like planets, Jupiter and Saturn are called recent planets, Uranus and Neptune are called averaging planets). Six of the eight are surrounded by natural satellites. These stars are conventionally regarded as the moon because the Earth's satellites are called the moon. The outer planets are surrounded by planetary rings composed of dust and many small particles. Except for the earth, planets visible to the naked eye are named after the five elements, and in the West, all are named after the gods in Greek and Roman mythological stories.

Tyche: February 15, 2011 news [1], a new planet may be found at the edge of the , with a mass of 4 times that of Jupiter, which will become the ninth largest planet and the largest planet, with orbit about 15,000 astronomical units away from the sun. Data on whether this gas behemoth, Tyche, located outside the Oort cloud, exists at the end of the year. Scientists believe that NASA's "Wide Area Infrared Detector" (WISE) has collected evidence in this regard. Daniel Whitmeier and John Matthewser, based on the angle of the comet, were first pointed out that the existence of Tyche, may be mainly composed of hydrogen and helium, have a Jupiter-like atmosphere, and have spots, rings and clouds, and may have satellites. Currently named Tyche - the Greek goddess who controls the fate of cities.

sun

Seven wonders of the

The formation of the system is believed to be based on the nebula hypothesis, which was originally proposed independently by Kant and Laplace in 1796. This theory believes that the was formed 4.6 billion years ago in the collapse of a huge molecular cloud. This nebula was originally light years old and several stars were born at the same time. The elements traced back to ancient meteorites show that only the heart part of the supernova explosion can produce these elements, so the clusters containing the sun must be near the wreckage of the supernova. It may be that the shock waves from the supernova explosion increased the density of the nebula near the sun, allowing gravity to overcome the expansion pressure of internal gases to collapse, thus triggering the birth of the sun.

It is believed that through the accretion, various planets will be born from the remaining gas and dust in the clouds (Sun Nebula):

Once the young sun begins to generate energy, the solar wind blows matter from the protoplanetary disk into interplanetary space, thus ending the planet's growth. The young Taurus T-star stellar wind is much stronger than the older stars in the stable stage.

According to astronomers' speculation, the current will remain until the sun leaves the main sequence. Since the sun uses hydrogen inside it as fuel, in order to use the remaining fuel, the sun will become hotter and hotter, and the combustion speed will also become faster and faster. This causes the sun to keep brighter, with a brighter speed of about 10% brighter every 1.1 billion years.

From now on, about 7.6 billion years, the inner core of the sun will be hot enough to allow the outer hydrogen to merge, which will cause the sun to expand to 260 times its current radius and become a red giant. At this time, due to the expansion of volume and surface area, the total luminosity of the sun will increase, but the surface temperature will drop, and the luminosity per unit area will become darker.

Subsequently, the outer layer of the sun was gradually thrown away, and finally the core was exposed to become a white dwarf, an extremely dense celestial body, only the size of the earth but half the mass of the original sun. Finally, it formed a dark dwarf.

During the Big Bang, the explosion of the black hole caused its core and shell matter to

During the strong explosion, a fission reaction occurs. The fragments formed in the explosion rapidly surge, and their volumes range from several times to dozens of times, from dozens to hundreds of times, from hundreds to thousands of times, from thousands to tens of thousands of times, from tens of thousands to hundreds of times, from tens of thousands of times, from tens of thousands of times to hundreds of times, from tens of thousands of times to hundreds of times,... During the fission process, gas groups containing a large amount of hydroxide and other fusion substances are produced. The fusion-induced substances in these gas groups reach a certain amount, the volume and internal pressure of the gas group reach a certain level, and the nuclear fusion of the gas group is produced.

.In this way, the larvae of the star is formed. The larvae may merge with other stars or swallow the residual bodies encountered during the long journey, and continue to develop and grow and become today's sun [2]. The rapid rise of these fragments is actually a process of fission. During the fission process, some are maintained in the form of solid state. These substances and other solid matters meet at any time, and undergo physical changes or chemical changes through mutual attraction, and merge together;

The small solid or liquid substance encountered by the swallowing of the body makes its volume increase continuously and its mass continue to increase, and its ability to capture and attract other substances gradually increases. Finally, it attracts a larger solid substance, which has a certain anti-gravity effect, thus becoming a system of planets and satellites. The Earth we live in may be formed in this context. The Earth is one of the eight planets in the , and is ranked as the third in order from near to far away from the sun.

3]. It has a natural satellite - the moon, which forms a celestial system - the earth-moon system. The earth rotates from west to east, and at the same time revolves around the sun. The combination of earth's rotation and revolutionary movement produces the alternation of day and night on the earth and the changes of the four seasons on the earth. The speed of the earth's rotation is uneven. At the same time, due to the gravitational action of the sun, moon, planets, and various effects of matter inside the atmosphere, ocean and the earth, the direction of the earth's rotation axis in space and in the earth's body will change.

The Sun is the parent star of the , and the only star in the that glows, and is also the most important and important member. It has enough mass to allow the internal pressure and density to suppress and withstand the huge energy generated by nuclear fusion, and in the form of radiation, such as visible light, allow energy to enter space stably.

The position of the sun on the Hero chart

The sun is a medium-sized yellow dwarf in classification, but such a name is easy to misunderstand. In fact, in our galaxy, the sun is quite large and bright. Stars are classified according to the correspondence between the surface temperature and brightness of the Hero diagram. Usually, stars with high temperatures will be brighter, and stars following this rule will be located in the so-called main sequence zone, and the sun is in the center of this zone. However, there are not many stars that are larger and brighter than the sun, while there are many stars with dimness and low temperatures.

The sun is in its prime at the stage of star evolution and has not yet used up hydrogen that undergoes nuclear fusion in the core. The sun's brightness will continue to increase day by day, with the early brightness only 75% now.

Calculate the ratio of hydrogen to helium inside the sun, and think that the sun has completed half of its life cycle. In about 5 billion years, the sun will leave the main sequence zone and become larger and brighter, but with a lower surface temperature, and its brightness will then be thousands of times higher than it is now.

The sun is the first star family star born in the late stage of the universe's evolution. It has more metals heavier than hydrogen and helium than the stars of the second star family (this is astronomy saying: all metals with atomic number greater than helium.). Elements heavier than hydrogen and helium are formed at the core of the star and must be released into the universe through supernova explosions. In other words, these heavy elements are only found in the universe after the death of the first generation of stars. The oldest stars only have a small amount of metal, and later they are born with more metals. High metal content is considered the key to solar energy's development of planetary systems, because planets are formed from accumulated metal matter.

The inner is traditionally the name of the terrestrial planets and asteroid belt regions, mainly composed of silicates and metals. This area is squeezed close to the sun, and its radius is shorter than the distance between Jupiter and Saturn.

Inner planet

All inner planets

The four inner planets or terrestrial planets are characterized by high density, consisting of rocks, with only a small number or no satellites, and no ring system. They are composed of minerals with high melting points, such as silicate minerals, the Earth's crust and semi-fluidic mantle, and the metal core composed of iron and nickel. Three of the four (Venus, Earth, and Mars) have a substantial atmosphere, all with impact craters and geological surface characteristics (grapes and volcanoes, etc.). The inner planets are easily confused with inner planets (Mercury and Venus) that are closer to the sun than the Earth. The planets run on one plane and head in one direction.

Mercury (0.4 astronomical unit) is the closest to the sun and the smallest planet (0.055 Earth mass). It has no natural satellites. The only known geological characteristics besides impact craters, only crumbling ridges that were probably generated during early history and contraction. Mercury, including gas atoms bombarded by solar wind, only has insignificant atmospheres. It is currently impossible to explain the relatively huge iron core and thin mantle. Hypothesis includes the huge impact that stripped its shell, and the solar energy in young age suppressed the growth of the shell.

Venus (0.7 astronomical units) has a volumetric dimension similar to Earth (0.86 Earth mass), and like Earth, it also has a thick silicate mantle surrounding the core, and there are also evidence of thick atmosphere and internal geological activities. However, its atmospheric density is 90 times higher than Earth and is very dry, and there are no natural satellites. It is a scorching planet with a temperature of more than 400°C on the surface, which is likely to be caused by a large amount of greenhouse gases in the atmosphere. There is no clear evidence that Venus' geological activities are still in progress, but the atmosphere without magnetic field protection should be depleted, so it is believed that Venus' atmosphere is supplemented by the eruption of volcanoes.

Earth (1 astronomical unit) is the largest and most dense among the inner planets, and the only planet that is still ongoing and has life (scientists have not yet explored other creatures from space). It also has a unique water circle and observed plate structure among Earth-like planets. The atmosphere of Earth is also completely different from other planets, and is transformed into 21% free oxygen by living organisms. It has only one satellite, the moon; the moon is also the only big satellite among Earth-like planets. The Earth orbits (sun) for about 365 days and rotates for about 1 day. (The sun does not always hit the equator directly, because the earth tilts slightly when it rotates around the sun.)

Mars (1.5 astronomical units) is smaller than Earth and Venus (0.17 Earth mass), with only a thin atmosphere dominated by carbon dioxide. Its surface, such as Mount Olympus, has dense and huge volcanoes, and the Mariner Canyon has deep grabbings, indicating that there was still intense geological activity not long ago. Mars has two natural small satellites, Demos and Forbers, which may be captured asteroids.

Asteroid belt

The main belt of the asteroid and the Trojan asteroid

Asteroids are the most important members of the small celestial bodies of the , mainly composed of rocks and non-volatile matter.

The main asteroid belts are located between the orbits of Mars and Jupiter, 2.3 to 3.3 astronomical units away from the Sun. They are considered to be residual matter that was disturbed by Jupiter's gravitational disturbance during the formation of the and failed to aggregate.

The scales of asteroids range from hundreds of kilometers to microns. Except for the largest Ceres, all asteroids are classified as small bodies in the , but there are several asteroids, such as Vesta and Health, who may be reclassified as dwarf planets if they can be proven to have reached hydrostatic equilibrium.

The asteroid belt has tens of thousands, possibly millions of small celestial bodies with a diameter of more than one kilometer. Despite this, the total mass of the asteroid belt is still impossible to reach one thousandth of the mass of the earth. The members of the main belt of the asteroid belt are still sparse, so no spacecraft has ever had an accident while traveling through.

Small celestial bodies with diameters of 10 to 10.4 meters are called meteor bodies.

Ceres (2.77 astronomical units) is the largest celestial body in the main belt and the only dwarf planet in the main belt. Its diameter is close to 1,000 kilometers, so its own gravity is enough to make it a sphere. When it was discovered in the early 19th century, it was considered a planet, and was reclassified as an asteroid in the 1850s because more small celestial bodies were discovered; in 2006, it was reclassified as a dwarf planet.

Asteroid family

Asteroids in the main belt can be divided into several asteroid groups and asteroid families according to orbital elements. Asteroid satellites are small celestial bodies orbiting larger asteroids, and their identification is not as clear as satellites orbiting planets, because some satellites are almost as large as the orbited parent bodies.

Comets are also found in the main belt, which may be the main source of water on Earth.

The position of the Troy asteroid is at points L4 or L5 of Jupiter (the unstable gravitational equilibrium point in front and behind the planetary orbits), but the name "Troy" is also used in small celestial bodies located at Lagrangian points in other planets or satellites. The Hilda family is an asteroid family whose orbits resonate with Jupiter 2:3. When Jupiter orbits the sun for two circles, these asteroids will orbit three circles around the sun.

The inner also contains many "naughty" asteroids and dust particles, many of which will pass through the orbits of the inner planets.

The central part of the is home to gas giants and their homes as satellites of planet size, with many short-period comets, including centaurs, also within this area. This area has no traditional name and is occasionally classified as the "outer ", although the outer usually refers to the region outside Neptune. In this area, the main component of solids is "ice" (water, ammonia and methane), unlike the inner dominated by rocks.

Extraplanet

All the exoplanets

The four planets on the outside, also known as Jupiter, encompass 99% of the known mass around the sun. The atmospheres of Jupiter and Saturn both have a large amount of hydrogen and helium, while the atmospheres of Uranus and Neptune have more "ice", such as water, ammonia and methane. Some astronomers believe that they should be another type, called "Uranus family" or "ice giants". These four gas giants have planetary rings, but only Saturn's rings can be easily observed from the earth. The name "exoplanet" is easily confused with "exoplanet", which actually refers to planets outside the Earth's orbit, and there are Mars in addition to exoplanets.

Jupiter (5.2 astronomical units) is mainly composed of hydrogen and helium, with a mass of 318 times that of the Earth and 2.5 times the total mass of other planets. Jupiter's abundant internal heat causes some approximately permanent features in its atmosphere, such as the cloud belt and the Great Red Spot. Jupiter has been discovered with 63 satellites, the largest of which are Ganemide, Calisto, Eo, and Europa, showing similar characteristics of Earth-like planets, such as volcanic action and internal heat. Ganemide is larger than Mercury and is the largest satellite in the .

Saturn (9.5 astronomical units), famous for its obvious ring system, is very similar to Jupiter, such as the structure of the atmosphere. Saturn is not very large, with a mass of only 95 times that of Earth. It has 60 known satellites, Titan and Enceladus, with huge ice volcanoes, showing signs of geological activity. Titan is larger than Mercury and is the only satellite in the that actually has an atmosphere.

Uranus (19.6 astronomical units) is the lightest exoplanet with a mass of 14 times that of the Earth. Its rotation axis is inclined to 90 degrees to the ecliptic, so it lies horizontally orbits the sun, which is very unique among planets. Among gas giants, its core temperature is the lowest and only radiates very little heat into space. Uranus has 27 known satellites, the largest of which are Titania, Oberon, Umberyell, Erell, and Miranda.

Although Neptune (30 astronomical units) looks smaller than Uranus, its higher density makes its mass still 17 times that of the Earth. Although it radiates more heat, it is far less than Jupiter and Saturn. Neptune is known to have 13 satellites, and the largest Triton still has active geological activities, with geysers that erupt liquid nitrogen. It is also the only retrograde satellite in the . There are some asteroids with 1:1 orbit resonance in Neptune, forming the Trojan Group of Neptune.

Comets belong to small celestial bodies in the , usually with a diameter of only a few kilometers, mainly composed of volatile ice. Their orbits have high qiu-

, and the perihelion is generally inside the orbit of the inner planet, while the axial point is outside Pluto. When a comet enters the inner , its proximity with the sun will cause the sublimation and ionization of matter on its cold surface, producing coma and dragging out the comet tail composed of gas and dust particles that can be seen by the naked eye.

Short-period comets are comets with orbital periods shorter than 200 years, and long-period comets can be as long as thousands of years. Short-period comets, such as Halley's Comet, are believed to have originated from the Kuiper Belt; long-period comets, such as the Hale Popp, are believed to have originated from the Ort Cloud. There are many groups of comets, such as the Cruz comets, which may originate from a collapsed parent. Some comets have hyperbolic orbits that may come from outside the , but it is difficult to accurately measure these orbits. Comets whose volatile matter is dispelled by the heat of the sun are often classified as asteroids.

The centaur herd is scattered in the range of 9 to 30 astronomical units, that is, orbits between Jupiter and Neptune, similar to the celestial bodies dominated by comets. The largest known celestial body of the centaur herd is 10199 Chariklo, with a diameter of 200 to 250 kilometers. The first one to be discovered was 2060 Chiron, because it produces coma like a comet when approaching the sun, and is currently classified as a comet. Some astronomers classify the centaur as discrete celestial bodies inside the Kuiper belt, and regard it as a continuation of the external discrete discrete disk.

Neptune area

In areas outside Neptune, commonly known as the outer or the outer Neptune region, it is still a vast undetected space. This area seems to be the world of small celestial bodies in the (the largest diameter is less than one-fifth of the earth and the mass is much smaller than the moon), and is mainly composed of rock and ice.

The Kuiper Belt, originally in its form, was believed to be a ring belt composed of debris and wrecks of ice, which are 30 to 50 astronomical units from the sun. This area is considered to be the source of short-period comets, such as Halley's Comet. It is mainly composed of small objects in the , but many of the largest objects in the Kuiper Belt, such as Chuangshen, Varouna, 2003EL61, 2005FY9 and Erkus, may be classified as dwarf planets. It is estimated that 100,000 objects with diameters greater than 50 kilometers in the Kuiper Belt will have more than one-tenth or even one-tenth of the earth's mass. Many Kuiper Belt objects have more than two satellites, and most of the orbits are not on the ecliptic plane.

The Kuiper Belt can be roughly divided into two parts: resonance belt and traditional belt. The resonance belt is composed of celestial bodies that have resonance relationship with Neptune's orbit (when Neptune revolves three times, it circles two times, or only one circle when Neptune revolves two times). In fact, Neptune itself is also a member of the resonance belt. Traditional members are celestial bodies that do not resonate with Neptune and are scattered within the range of 39.4 to 47.7 astronomical units. The traditional Kuiper Belt celestial bodies are classified as QB1-like objects under the name of 1992QB1, one of the three initially discovered.

Pluto and Charon

Pluto and three known moons

It is not yet certain whether Charon should be classified as a satellite currently considered or a dwarf planet, because the center of mass of Pluto and Charon orbiting each other is not below the surface of either, forming a Pluto-Caron binary star system. The other two small satellites, Nix and Hydra, orbit Pluto and Charon.

Pluto resonates with Neptune in the resonance zone (when Pluto orbits the sun for two circles, Neptune revolves three circles). Celestial bodies with this orbit in the Kuiper belt are collectively called Pluto-like celestial bodies.

The discrete disc overlaps with the Kuiper belt, but extends outward to a farther space. The celestial bodies in the discrete disc should be in the early stages of the formation of the , because the gravitational disturbance caused by Neptune's outward migration was thrown from the Kuiper belt into a recurring orbit. The perihelion of most discrete ecliptic bodies is in the Kuiper belt, but the aphrodisiac can be as far as 150 astronomical units; the orbit also has a great inclination angle to the ecliptic plane, and are even perpendicular to the ecliptic plane. Some astronomers believe that discrete ecliptic bodies should be another part of the Kuiper belt and should be called "discrete celestial bodies in the Kuiper belt".

Eris (136199Eris) (average distance of 68 astronomical units), also known as Zina, is the largest known ecliptic discrete celestial body and has triggered the debate on what a planet is. Its diameter is at least 15% larger than Pluto, and is estimated to be 2,400 kilometers (1,500 miles), and is the largest of the known dwarf planets. Eris has a satellite, Dysnomia, and its orbit also has a large qiu-rate like Pluto. The distance of the perihelion is 38.2 astronomical units (about the average distance between Pluto and the Sun), and the aurora reaches 97.6 astronomical units, and the inclination angle to the ecliptic surface is also very large.

Scientists from the California Institute of Technology discovered the planet on the edge of the in 2003, numbered 2003UB313, temporarily named Zina, and did not announce the discovery to the outside world until July 29, 2005. It is reported that astronomers from various countries denied it as a large planet at the International Astronomical Federation Conference on August 24, 2006.

According to reports, Zina's diameter is about 1,490 miles, which is 77 miles larger than the dwarf planet Pluto at the edge of the . Zina is 9 billion miles away from the sun, which is about three times the distance between Pluto and the sun, which is about 97.6 astronomical units. One astronomical unit refers to the distance between the sun and the earth. Zina orbits the sun for 560 years. It is also the farthest star body in the we know so far, and it is the third brightness in the "Kuiber Belt". It is lower than the temperature on the surface of Pluto, about minus 214℃, and is a very unsuitable place to live.

The star is round, probably twice as large as Pluto. He estimates that the newly discovered star is estimated to be 2,100 miles in diameter, 1.5 times that of Pluto.
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