Desdichado
Hero
In the 80s, I'm not aware of any reason why Pluto would not have been a planet, other than the fact that it was discovered in 1978 to be a fair amount smaller than expected. But there was no knowledge of an entire population(s) of trans-Neptunian objects. It wasn't really until the discovery of 1992 QB1 that astronomers (not astrologers) started crying for Pluto to be "downgraded." Prior to that, there really wasn't anything else that it could have been.
I do agree, though that if the definition of a planet includes Pluto, I can't think of any way that it could exclude 2003 UB313 unless Pluto is simply arbitrarily included by fiat.
Still--I stress again that my friend's kid wasn't taught about 2003 UB313 in school; she was taught about a mythical "Planet X" which is not the same thing.
I do agree, though that if the definition of a planet includes Pluto, I can't think of any way that it could exclude 2003 UB313 unless Pluto is simply arbitrarily included by fiat.
Still--I stress again that my friend's kid wasn't taught about 2003 UB313 in school; she was taught about a mythical "Planet X" which is not the same thing.
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