So Is It A Planet?
And Why Not???
From CNN on-line:
It was three years ago Monday that the International Astronomical Union demoted Pluto from a planet to a dwarf planet, a decision that made jaws drop around the world.
An outcry followed, textbooks had to be rewritten, long-held beliefs were shattered, and many people felt our cosmic neighborhood just didn’t seem the same with eight — instead of nine –planets in the solar system.
Well, even though I was working on the New Horizons Mission to Pluto at the time, my jaw didn’t exactly drop. The debate had been going on for awhile. Besides. It’s just nomenclature. As it was, ever since Arthur C. Clarke pointed out that Europa was every bit as interesting as Jupiter, astronomically speaking, many of us had sort of realized early on that there was more to the Solar System than just planets, comets and asteroids.
Not that planets were downgraded, mind you. It was more like everything else was upgraded in importance. The icing on that particular cake was that astronomers began to realize that even the planets were more varied than originally supposed. There weren’t just two kinds; rocky like the Earth and gaseous-giants like Jupiter. It seems better now to recognize that Uranus and Neptune might be yet a third class – with interiors that are much different than the others, and with unique formation-histories to boot. The discovery of large ice-balls in the outer solar system, of which Pluto is the earliest known (and probably best) example, is merely the last step in that march.
So, planet or no, Pluto is going to be a great place to visit. Too long a commute to live there, however.