"Hundred Thousand Whys Traveling in the Universe" series content is exclusively original by "Science Vitamin" . It uses language, pictures and videos to help you understand the earth, understand the stars, explore the universe, and have interesting and informative knowledge for a few minutes every day to help you become a science expert.
Pluto
Pluto's "household account"
Keywords 1:Pluto and its satellite
Keywords 2:Pluto's final "settlement"
Keywords 3: "New Horizons" probe
From Nether outside, it is the world of Pluto and many small celestial bodies. Pluto was once considered one of the nine planets in the solar system for a long time and is also the farthest from the sun. Pluto was discovered by American astronomer C.W.Tongbo through observations through sky surveys in 1930, and was named "Pluto" after the "God of Hell" in Greek mythology. The name was proposed by Winniesha Bernie, an 11-year-old girl from Oxford, England. She felt it was suitable for a planet that was always dark and cold. In Chinese, it is translated as "Pluto".
The distance from Pluto to the Sun is almost 40 times that of the distance from the Earth to the Sun, so the received sunlight is very weak. Even when facing the sun, the temperature is as low as -220℃. Except for a few gases such as hydrogen and helium, other gas substances will condense into liquid or solid states. Pluto has a diameter of only 2300 kilometers. It takes 248 years for Pluto to orbit one week, and it has only revolved around the sun by 1/3 since it was discovered.
0 Pluto has 5 satellites. The largest one was discovered by American astronomer Christie in 1978. People named it " Charon ". The name of the shipman who transported the dead on Styx in Greek mythology is named " Mingwei Yi " in Chinese. In 2005, NASA discovered Netherworld II and Netherworld III through the Hubble Space Telescope , and in 2012, Netherworld IV and Netherworld IV were discovered. They were both very small and only a few dozen kilometers in diameter.
people once regarded Pluto as the ninth planet in the solar system, but its planetary identity has been questioned by people.
Compared with other planets in the solar system, Pluto is really too small. In terms of size, our moon can also be as big as three and a half Pluto. Pluto's material density is twice that of water, much smaller than the average density of the earth. About 500 Plutos are as heavy as one Earth.
Planets are orbiting the sun in an elliptical orbit close to the right circle, but Pluto's orbit is much flattering. When it passes perihelion, it is closer to the sun than Neptune. That is, it intersects with Neptune's orbits. Moreover, the planet's orbital plane is very close to the ecliptic plane of and , while the angle between the orbital plane of Pluto and the ecliptic plane is as high as 17°.
In addition, among the eight known planets, Mercury, Venus, Earth and Mars (collectively referred to as Earth planets ) closer to the sun are all smaller in size, but their density is quite large; Jupiter, Saturn, Uranus and Neptune (collectively referred to as Wood planets ) farther away from the sun are all very large in size, but their density is very small. Pluto is farther away from the sun, but is particularly small and has a larger density than that of a Muslim planet. These situations also cause people to question: Is Pluto a veritable planet?
In fact, as early as 1936, British astronomer Ritterton proposed that Pluto was probably a large satellite orbiting Neptune with Triton and . It once approached Triton, which changed their motion under the interaction of gravity. As a result, Pluto separated from Neptune and became the ninth largest planet, and Triton became an abnormal satellite in reverse due to the reverse impulse.
Since the 1990s, astronomers have successively discovered a batch of Kuiper belt objects, which are very similar to Pluto. In particular, the "size" of , is even bigger than Pluto. This situation eventually led to the International Federation of Astronomical Astronomy passing a resolution in 2006 to relegate Pluto to " dwarf planet ".
In January that year, the United States launched the first Pluto probe, "New Horizons".It will fly to Pluto in 2015 to conduct a close investigation of Pluto, the Pluto Guards and the Kuiper Belt. "New Horizons" discovered a "heart-shaped" plain on Pluto, and was named "Tangbo District" after the discoverer of Pluto. Photos sent back by "New Horizons" show that there are mountains, plains, and complex "snakeskin" terrain and "tortoiseshell" terrain on the surface of Pluto.
END
