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知乎，让每一次点击都充满意义 —— 欢迎来到知乎，发现问题背后的世界。Pluto was uncovered applying photographic plates inside of a blink comparator; its moon Charon was found forty eight yrs later on in 1978 by U.S. Naval Observatory astronomer James W. Christy by very carefully inspecting a bulge in Pluto's image on