Being an 'old man' of 44, myself, I can remember when MERCURY, not PLUTO was considered to be the smallest of the nine planets. (I'm sure Neil can confirm this for me). Of course this was before it was discovered that Pluto had such a sizable moon that it was re-classified back in the 80s as a "double-planet" by some.
I can even remember some who once thought Pluto might be just a large comet, trapped in a non-eccentric orbit around the sun (thus it never got close enough to have a "tail").
Pluto's lack of planetary peers, being too dogone far away to study in detail, AND having been the culmination of early 20th century excitment over the hopeful discovery of a so-called Planet "X", beyond Neptune all contributed to Pluto's possibly over-inflated status as a "planet".
Therefore I suppose the "demotion" is justified.
At least the astronomical establishment had the decency to wait until after Clyde Tombaugh died before they officially "demoted" the planet he discovered back in the 1930's.
Gk. "planetes" means "wanderer," because from Earth they appear to follow irregular paths. By this definition all observable entities orbiting the Sun qualify as planets. Asteroids are borderline since they're hard to observe.
No definition is perfect but this seems less objectionable. Planets are mentioned in Scripture @ 2 Ki. 23:5, and this certainly rules out the sun, the moon, and stars.
Totally uncalled for. I grew up with the nine planets and have always been fascinated by astronomy. Pluto will always be a planet to me. Pluto has more in common with the other planets than with asteroids and comets.
According to BBC, this is the Priesthood's reasoning,
"The scientists agreed that for a celestial body to qualify as a planet: - it must be in orbit around the Sun - it must be large enough that it takes on a nearly round shape - it has cleared its orbit of other objects Pluto was automatically disqualified because its highly elliptical orbit overlaps with that of Neptune. It will now join a new category of dwarf planets."
Just for fun, these are reasonable objections: 1) No object is a true spheroid or even elliptoid, all measured objects are irregular. "Large enough" & "nearly round" are vague & thus meaningless; 2) Comets & cosmic particles pass thru all orbits (Jupiter was hit by one), thus disqualifying all planets.
I say that a planet must have blue skies and good surfing. Thus there is only one planet, Earth.
Think of all the textbooks that must be revised now! There's institutional science for you - its High Priests have spoken, make it so. Even something as objective as a planet now evades clear definition. How large must it be? How circular must its orbit be? How far away can it be?
Of course they CAN tell us what is human and what is not.
Yet many people still think it has truth to tell us. Philosophy isn't studied enough.