American scientists officially announced on the 29th that they had discovered the tenth largest planet in the solar system. It is three times farther from the sun than Pluto and 1.5 times as large as Pluto. It was named 2003UB313.
As early as early 2004, American scientists also found a red asteroid 12.9 billion kilometers away from the earth and named it "Sedna". At the time, it was considered the tenth largest planet in the solar system. However, many astronomers raised doubts, and after repeated identifications by scientists, they finally thought it was not qualified.
Currently, there are nine planets in the solar system, namely Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune and Pluto.
Caltech planetary astronomer Mike Brown and others announced on the 29th that they had discovered the tenth largest planet in the solar system outside Pluto. It is 1.5 times the size of Pluto and is as far away from the sun as Pluto. 3 times, tentatively named 2003UB313. Since then, the National Aeronautics and Space Administration (NASA) also posted news on its website, saying that "the tenth planet has been discovered."
How significant is this newly discovered star? Is it possible that the statement "there are nine planets in the solar system" that has been used for decades in domestic primary and secondary school textbooks and various popular science books can be rewritten? Is the "tenth planet" theory true? Who is the authority to determine whether the nova belongs to the large family of planets in the solar system? With these questions, the reporter asked Dr. Lin Qing from the Shanghai Observatory of the Chinese Academy of Sciences.
The tenth largest planet was predicted for 75 years
According to Lin Qing, the idea of ??the existence of the tenth largest planet in the solar system has long been known in the astronomy community. In 1930, American astronomers discovered a new star beyond Neptune. In the same year, the International Astronomical Union (IAU) determined it to be the ninth planet in the solar system and named it "Pluto".
However, since 1930, the astronomical community has continuously put forward the theory that there is a tenth planet in the solar system, and they are still working hard to observe to confirm this inference. Therefore, in recent years, one after another people have claimed to have found the tenth planet, and each discovered star is larger than the last. The one with the greatest impact was undoubtedly the discovery of a red asteroid 2003VB12 12.9 billion kilometers away from the earth by American scientists in early 2004. At that time, its discoverers believed that it was the tenth largest planet in the solar system, and named it "Sedna" after the ocean goddess in Inuit myths and legends. 》》》American astronomers discovered the most distant celestial body in the solar system
However, because the diameter of "Sedna" is only 71 times that of Pluto, many astronomers raised questions. After repeated identifications, they finally considered it not qualified. , "Sedna" has been officially classified as an "asteroid". But this time the new star discovered by the Americans was larger than Pluto, which really attracted the attention of the scientific community. Lin Qing said that the discovery of 2003UB313 is indeed of great significance. It forces people to re-research the structure of the solar system and the concept of planets.
New discoveries shake Pluto's status
The reports by NASA and Western media have the same feature, which is to use "planet" to call this new celestial body, and Called the tenth planet in the solar system. However, in Lin Qing's view, it is too early to propose the "tenth planet". The emergence of 2003UB313 will make people rethink Pluto's status in the solar system and how to define the concept of "planet".
According to reports, many astronomers have always regarded Pluto as an "alien" among the planets in the solar system. Pluto's diameter is only 2390 kilometers, only 5 times the diameter of its "neighbor" Neptune (49528 kilometers), and less than half of Mercury (4879 kilometers); its mass is also the smallest among the nine planets, even smaller than the moon's mass . Its orbit and movement patterns are also very different from the other eight "sisters" in the solar system.
Many scientists have proposed to exclude Pluto from the list of planets in the solar system and treat it as an asteroid.
Another way is to define the eight major planets as "major planets" and define celestial bodies orbiting the sun with a diameter greater than 2,000 kilometers and less than 4,879 kilometers (Mercury) as "quasi-planets." (Note: In this way, both Pluto and the newly discovered 2003 UB313 will be regarded as quasi-planets.)
Although the proposal to remove Pluto from the planet's "throne" was rejected by the IAU in 1998, many Scientists have always believed that there are actually only eight major planets in the solar system. The stars other than Neptune belong to the Kuiper Belt (asteroid belt). Pluto is also a larger asteroid.
Lin Qing said that "planet" in Chinese has always been a vague concept, while English has a clear distinction between planet and asteroid. Now, the facts of astronomical observations are there, and "planet" is just an artificial definition. It is time to reconsider the definition of "planet". He also said that if this new celestial body is defined as the tenth planet in the solar system, perhaps in the next 10 years, dozens of so-called "planets" smaller than Mercury and larger than Pluto will "pop up" in the solar system.
Don’t rush to change the textbooks yet
For decades, primary and secondary school geography teachers have told students that there are nine planets in the solar system. Will this new discovery by American scientists change the answers to geography test papers for primary and secondary school students? Lin Qing said with a smile that it is better to maintain the status quo for current middle school textbooks. Because everything is hard to say now, NASA is not the authority to decide whether 2003UB313 belongs to the tenth planet. Pluto's status may need to be reconsidered. Everything must wait for the authoritative department, the International Astronomical Union, to carefully consider it before making a conclusion.
Netizens rushed to give the new star a good name
As soon as the news that American scientists discovered the so-called "tenth largest planet in the solar system" came out, it immediately aroused the attention of many star fans, including those in China. Netizens’ comments. According to international practice, if this new star can really be counted as the "tenth planet", it will be given the name of one of the gods in Western mythology, rather than named after its discoverer. What kind of good name to give this "new member" of the solar system has become one of the focuses of debate among domestic star fans and netizens.
As of midnight today, netizens on Sina have made 547 comments about "The discovery of the tenth largest planet in the solar system"; and the "Tianzhiwen" website where star fans in Shanghai gather has comments about "the tenth largest planet" "The discussion's click-through rate has reached more than 1,000 times. In a post titled "The Name of the 10th Planet," dozens of netizens cited nearly ten names suitable for this new star from Roman and Greek mythology.
Many netizens suggested that since Pluto is called "Pluto", this new star can be named "Thanatus (the god of death in Greek mythology)" or "Hypnos" (the god of death in Greek mythology). "Goddess of Sleep", "Hecate (Goddess of Night)", and some netizens think it should be given a nice name, such as "Aphrodite (Goddess of Love and Beauty)". However, Dr. Lin Qing, director of the Sheshan Observatory of the Shanghai Observatory of the Chinese Academy of Sciences, said that the names of the major planets in the solar system are indeed named after mythical names, but the name of this new star needs to be finalized by the International Astronomical Union