Pluto is most definitely a planet — and should never have been downgraded, say some scientists

(CNN)Make Pluto great again? New images of Pluto show mountains, but no craters And, Metzger also points out, the standard used to classify planets changed in the 1950s after astronomer Gerard Kuiper said what really determines what is and what isn’t a planet is how a celestial body is formed.…

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