Information about the Eight Planets, Information about the Eight Planets Introduction to the Eight P

The Eight Planets are eight celestial bodies that orbit the Sun and are massive enough. They are: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune.

Unlike the concept of the nine planets mentioned before 2006, Pluto was classified as a dwarf planet and removed from the nine planets of the solar system in Resolution 5 adopted at the 26th International Astronomical Union in Prague on 24 August 2006.

Eight planets. The eight planets refer to the eight planets of the solar system, from the distance from the sun from small to large, they are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune. Pluto, discovered in 1930 by American astronomer Tombo, was once considered a large planet, but with the discovery of a larger and farther celestial body than Pluto, the 26th Congress of the International Astronomical Union held on August 24, 2006, defined it as a dwarf planet.

A new definition of planets.

Eight planets. One is that it must be a celestial body orbiting a star. The second is that the mass is large enough to rely on its own gravity to make the celestial body spherical.

The third is that there are no other objects in the vicinity of its orbit. Pluto is at odds with the third one, and Pluto's orbit intersects with Neptune.

Pluto is out of the ranks.

The reasons why Pluto was excluded from the big planets are: first, because the process of its discovery was based on a false theory; Second, because its mass was incorrectly estimated at the beginning, it was mistakenly included in the ranks of large planets, and it was classified as a dwarf planet.

Mercury. English name: Mercury Mercury is the closest to the Sun and is the smallest and lightest planet in the solar system. Often haunted at the same time as the sun, China called it "Chenxing" in ancient times. Mercury is smaller in diameter than Ganymede and Titan.

Basic parameters. Orbital half-length: 57.91 million km ( AU) of Ganymede.

Revolution period: days Rotation direction: from west to east Average orbital velocity:

km per second orbital eccentricity: orbital inclination: degrees Planetary equatorial radius:

2440 km Mass (Earth's mass = 1): Density: grams cubic centimeters Rotation period:

Number of satellites per day: no orbit: 57,910,000 km (astronomical units) from the Sun

Name**. In ancient Roman mythology, Mercury was the god of commerce, travel, and theft, i.e. Hermes in ancient Greek mythology, the god of messengers to the gods, perhaps because of the speed at which Mercury moves in the sky, which gave it its name.

1. The eight planets refer to the eight major planets of the solar system, which are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune according to their distance from the sun.

2. Most of the rotation directions of the eight planets are also consistent with the rotation directions. Only Venus and Uranus are two examples. Venus rotates in the opposite direction to its orbit, while Uranus rotates "lying" at an angle of 97° to its orbit.

3. Definition of planets: first, celestial bodies that must orbit stars; The second is that the mass is large enough to rely on its own gravity to make the celestial body spherical. The third is that there should be no other objects in the vicinity of this orbit (clean up other objects in its orbit). According to this division, there are only eight planets in the solar system: water, metal, earth, fire, wood, and earth, plus the king of heaven and the king of the sea.

4. Different from the concept of nine planets mentioned before 2006, in Resolution 5 adopted at the 26th International Astronomical Union held in Prague on August 24, 2006, Pluto was classified as a dwarf planet and removed from the nine planets in the solar system.

The eight planets are the eight large planets of the solar system, and they are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune in descending order from near to far.

The distance of the eight planets from the Sun.

1.Mercury. Mercury is the innermost and smallest planet of the eight planets in the solar system, Mercury is a terrestrial planet, because it is very close to the sun, so it will only appear in the early morning called the star star, or appear at dusk as the evening star.

Unless there is a solar eclipse, Mercury is usually invisible under the sun's rays. Mercury is located at a distance of about 57.9 million kilometers from the Sun.

2.Venus. Venus is the closest planet to Earth (Mars is sometimes closer).

The brightness in the night sky is second only to that of the Moon, and Venus reaches its brightest only before sunrise or after sunset. It appears in the eastern sky early in the morning and is called "enlightenment"; In the evening, it is on the west side of the sky and is called "Chang Gung". Venus is located about 108.2 million kilometers from the Sun.

3.Earth. The Earth is the only celestial body in the universe where life is known to exist, and it is home to millions of living beings, including humans.

The Earth is the terrestrial planet with the largest diameter, mass and density in the solar system, and it has a natural satellite, the Moon, which forms a celestial system, the Earth-Moon System. The Earth is located about 149.6 million kilometers from the Sun.

4.Mars. Mars was called the "glowing star" in ancient China, and the phenomenon of Mars "staying" in the heart is called the glowing confusion and guarding the heart.

Mars (Greek: Ares) is known as the god of war. This may be due to its bright red color; Mars is sometimes referred to as the "Red Planet".

Mars is located about 227.94 million kilometers from the Sun.

5.Jupiter. Jupiter is the largest and fastest rotating planet among the eight planets in the solar system, and it is also the most massive of the planets in the solar system, with a mass of one-thousandth of the sun and twice the mass of the other seven planets in the solar system combined.

Jupiter is located about 778.33 million kilometers from the Sun.

6.Saturn. Saturn is the second largest planet among the eight planets, called "Zhenxing" in ancient China, and Saturn in ancient Europe (ancient Greece) was Cronus, and in ancient China it was called Fuxing.

Second only to Jupiter in mass and diameter, it is the least dense planet in the solar system and can float on water. Saturn is about 1,429.4 million kilometers from the Sun.

7.Uranus.

Uranus is one of the eight planets in the solar system, the seventh planet in the solar system from the inside out, the third largest in the solar system (larger than Neptune) and the fourth most massive (smaller than Neptune), almost lying horizontally orbiting the sun. Uranus is about 287099 million kilometers from the Sun.

8.Neptune.

Neptune is the far-reaching planet of the eight planets in the solar system. Neptune's brightness is only equal and can only be seen in astronomical telescopes. Because of its glowing pale blue light, Westerners call it "Neptune", the god of the sea in Roman mythology.

In Chinese, it translates as Neptune. Neptune is located 450400000 kilometers from the Sun.

The eight planets are listed in order of size as 1, Jupiter, 2, Saturn, 3, Uranus, 4, Neptune, 5, Earth, 6, Venus, 7, Mars, 8, Mercury

According to the new definition of planets adopted by the Assembly of the International Astronomical Union on 24 August 2006, a "planet" is a celestial body orbiting the Sun that has a gravitational force sufficient to overcome its rigid physical strength to make the body spherical and capable of clearing other objects in the vicinity of its orbit. Of the "nine planets" of the solar system's tradition, only Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune meet these requirements. Pluto was automatically downgraded to a "dwarf planet" because its orbit intersected Neptune's orbit and did not meet the new definition of a planet.

For decades, scientists generally believed that there were nine planets in the solar system, but with the discovery of an object larger and farther away than Pluto, the debate over Pluto's status as a large planet has intensified.

Unlike the concept of nine planets mentioned before 2006, in Resolution 5 adopted at the 26th International Astronomical Union held in Prague on 24 August 2006, Pluto was classified as a dwarf planet and removed from the list of nine planets in the solar system. The mass is large enough to rely on its own gravitational pull to make the celestial body appear spherical. Celestial bodies that also have sufficient mass and are spherical in shape, but cannot clear other objects in the vicinity of their orbits are called "dwarf planets", and Pluto fits this definition and has been recognized as a "dwarf planet" by the International Astronomical Union.

So Pluto is classified as a dwarf planet. Since then, there have been only eight planets in the solar system.

Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune, and Pluto, some "astronomers" privately classify Pluto as a "dwarf planet", but it is difficult to justify it.

One is because the process of its discovery is the basis of a wrong theory, and the other is because its mass was incorrectly estimated in the first place, and it was mistakenly included in the ranks of large planets. Therefore, at the Congress of the International Astronomical Union, it is necessary to "justify the name of the grass dry star"."became the focus of the conference, for which astronomers came up with various proposals.

On August 24, 2006, the 26th General Assembly of the International Astronomical Union voted by more than 2,000 astronomers to approve that there are only eight planets in the solar system. Pluto, one of the traditional nine planets, is no longer considered a planet, but is included as a "dwarf planet."