The names of the nine planets in the solar system are all taken from Greek mythology, and the exact naming time is unknown.
1. Mercury
Mercury was discovered as early as 3 BC in Sumerian times. The ancient Greeks gave it two names: Apollo when it first appeared in the morning and Hermes when it flashed in the night sky. However, ancient Greek astronomers knew that these two names actually refer to the same star, and Heraclitus (a Greek philosopher in the 5th century BC) even thought that Mercury and Venus were not orbiting the earth, but orbiting the sun.
In ancient Roman mythology, Mercury was the god of commerce, travel and theft, that is, Hermes in ancient Greek mythology, the god who sent messages to the gods. Perhaps it was because Mercury moved fast in the air that it got its name.
2. Venus
Venus has been known since prehistoric times. Besides the sun and the moon, it is the brightest one. Just like Mercury, it is usually considered to be composed of two independent stars: the morning star is called Eosphorus and the evening star is called Hesperus, and Greek astronomers know this better.
Venus (Greek: Aphrodite; Babylonian: Ishtar) is the goddess of beauty and love. Perhaps it was named like this because it was the brightest planet in the known world for ancient people. There are also some objections that Venus is named because its surface is like a woman's appearance. )
3. The earth
The earth is the only name that doesn't come from Greek or Roman mythology. The word Earth comes from old English and Germanic. There are of course many other languages named here. In Roman mythology, the goddess of the earth is called Tellus－-fertile land (Greek: Gaia, Mother Earth). It was not until the Copernican era in the 16th century that people realized that the earth was just a planet. It is also the only planet in the solar system with liquid water.
4. Mars
Mars has been known to mankind since prehistoric times. Mars (Greek: Ares) is called the God of War. This may be due to its bright red color; Mars is sometimes called the "red planet". (Interesting note: Before the Greeks, the ancient Romans used to worship Mars as the god of farming. The aggressive Greeks, on the other hand, regarded Mars as a symbol of war, and the name of March was also derived from Mars.
5. Jupiter
Jupiter is the fourth brightest object in the sky (after the sun, the moon and Venus; Sometimes Mars is brighter), Jupiter has been known to humans as early as prehistoric times.
Jupiter (a.k.a. Jove; Zeus, as the Greeks called him, was the king of God, the ruler of Mount Olympus and the protector of Rome. He was the son of Cronus (Saturn).
6. Saturn
Saturn was discovered in prehistoric times. Galileo first observed it through a telescope in 161 and recorded its strange trajectory, but he was also confused by it. The early observation of Saturn is very complicated, because every few years when Saturn is in its orbit, the earth will pass through the plane where Saturn's rings are located.
in Roman mythology, Saturn "Tournous" is the name of Saturnian. Cronus, the god of agriculture in Greek mythology, is the son of Uranus and Gaia and the father of Zeus (Jupiter). Saturn is also the root of Saturday in English.
7. Uranus
Uranus was systematically searched by William Herschel through a telescope and was discovered on March 13th, 1781. It was the first planet discovered in modern times.
Because the names of other planets are taken from Greek mythology, it was first proposed by Baud to be called "Uranus" (Uranus) for consistency, but it was not widely used until 185. Only one interplanetary probe has been to Uranus, which was completed by Voyager 2 on January 24, 1986.
8. Neptune
In ancient Roman mythology, Neptune (ancient Greek mythology: Poseidon) represents Poseidon. After Uranus was discovered, people noticed that its orbit was not consistent with what was inferred from Newton's theory.
So scientists predict that there is another distant planet, which affects the orbit of Uranus. Galle and d'Arrest observed Neptune for the first time on September 23rd, 1846, and its location was very close to the location independently predicted by Adams and Leveille based on the observed positions of Jupiter, Saturn and Uranus.
9. Pluto
After the General Assembly of the International Astronomical Union was held on August 24, 26, Pluto was downgraded to a dwarf planet by voting, leaving only eight planets in the solar system. The saying of "nine planets" has become history, and it has been replaced by "eight planets".
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