Pluto's special story!.

<P Align=center> </ P> <P align=left> Technology Channel (tech.) reports: the debate about the status of Pluto, in the August 2006 International Astronomical Union (IAU) 26th General Assembly will come up a total .outbreak. .In theory, everyone is talking about what a planet, but Pluto is still the core of the contradiction between the actual body: it is in the end be considered planets? .Answer to this question will determine the planets and other small objects where the boundary. .</ P> <P align=left> the end, Pluto lost its status 70 years accounted for 9 --- solar system planets, from this can only be called a "dwarf planet." .Dwarf planet is an integral full name, not a "dwarf planet." .Dwarf planets are not planets, asteroids are not planets like the same. .Since then, this represented by Pluto, to a certain extent but could not be around the "competition" a clean sweep of objects will be called a dwarf planet, as distinguished from a solid 8-planet status. .</ P> <P align=left> the discovery of solar system object larger than Pluto and directly promote the transformation of the American scientist Mike Brown admitted, can not become the "Tenth Planet Finder," made him a little bit sad, but he .support the new definition, not in favor of an expanded family of planets to 12 or more. .Most astronomers to support the new definition. .</ P> <P align=left> retrospect, the first appearance of Pluto is very strange process. .As Uranus and prediction of the actual track does not match the speculation that this is another planet's gravitational disturbance caused by this smooth discovered Neptune. .However, Uranus, Neptune still can not fully explain the interference, so reasonable to conclude that scientists, outside the orbit of Neptune also have a large celestial bodies. .</ P> <P align=left> the efforts of several generations, a dim planet in 1930 the American astronomer Tombaugh in the field of vision, it is identified as the mysterious sinking unknown planet. .Away from the sun's shining, the planet Pluto was given the god of hell (pluto) the name, the Chinese called Pluto. .Pluto is also the first two letters pl astronomer Lowell (Percival Lowell) initials. .Lovell who have paid great efforts to find Pluto, but did not live to see Pluto's discovery. .</ P> <P align=left> However, it was gradually discovered that Pluto is much smaller than expected. .A smaller planet than the Moon, the orbit of Uranus is difficult to cause any significant effect on the quality of Uranus is to know ten times the Earth. .So people started looking for "Planet X" --- X can either be interpreted as the unknown, can also be interpreted as a Roman numeral 10. .However, Voyager 2 spacecraft in the use of the data obtained after recalculation of the quality of Neptune, problem solving, "the existence of planets beyond Neptune," just a misunderstanding, the existence of Planet X has become unnecessary. .</ P> <P align=left> how to do it Pluto? .It is because of this misunderstanding and get the planet was found status. .9 planets as it and the other 8 are very different. .It is too small, the track is too specific. .Other planets with the orbital plane of the ecliptic plane (Earth's orbital plane) are basically the same, but Pluto's orbit and the ecliptic plane appear before a large angle, like a crooked hat. .Other planets orbit is almost perfectly circular orbit of Pluto is a great elliptical eccentricity, its perihelion and aphelion distance from the sun as much as a difference of three billion kilometers. .</ P> <P align=left> For these reasons, the status of Pluto has not been strong. .It is as planet appears in the textbooks, popular science books and pamphlets in the planetarium, but many scientists are not satisfied, from time to time been suggested to have it dismissed. .As criticism ridden, its size was quite commensurate with its own popularity. .Of course, if things just so, the textbook is not right and wrong can not be changed. .</ P> <P align=left> However, the nature of human understanding of constantly rewriting, the discovery of the Kuiper belt completely changed our understanding of the edge of the solar system. .Kuiper American scientists in 1951 suggested that the outer solar system may have a large group of small celestial bodies around the sun. .In 1992, outside the orbit of Neptune was first discovered in a small dark object, since the existence of the Kuiper belt by the hypothesis of a reality. .So far, more than 100 kilometers in diameter Kuiper Belt objects have been found several hundred, according to speculation, Kuiper Belt Objects could reach 70,000. .</ P> <P align=left> continue to be discovered Kuiper Belt objects to re-examine the status of planet Pluto mission definition and more urgent. .2004's "Sedna" the largest possible diameter of 1,800 kilometers, almost equal to more than Charon and Pluto, the International Astronomical Union, a special committee to discuss at the beginning of the year the definition of a planet. .In 2005, larger than Pluto 2003UB313 also been introduced to the public, the matter has reached a settlement can not be level. .</ P> <P align=left> because these findings suggest that, beyond the orbit of Neptune from the sun, about 50 astronomical units (an astronomical unit is equivalent to the distance from Earth to the sun, about 1.5 billion km) area within ., Pluto is not dominated by the open area, and there are many "residents." .In this cold and crowded "communities" where Pluto is not a "boss." .</ P> <P align=left> today, Pluto is no longer the dominant edge of solar system objects in particular, however, as a "history of the planet, cultural planet" Pluto is still in the possession of the public mind and the history of astronomy .special status. .After all, in 70 years as the history of the planet, Pluto has been dramatic. .</ P> </ p>.