I remember learning all the planets in the solar system when I was 10. I made a model of it right after I made a model of a black hole (fold a piece of black posterboard in a conical shape, and voila! A black hole!) Now, according to the powers that be, we have to relearn the planets of the solar system. Pluto is officially no longer a planet.
Percival Lowell, who the Lowell Observatory in Flagstaff was founded by, was the first to predict that Pluto existed in 1905, but never saw it before he died in 1916. Only in 1930 was it discovered, and named after the god of the underworld (and the name was also fitting because it contained Lowell's initials). Now, 76 years later, we have to say goodbye to planet Pluto and hello to dwarf planet Pluto.
I'm not sure why it bothers me so much. After all, it is merely a logical change in definition (Pluto's orbit overlaps that of Neptune's and thus it can't stand alone as a planet). We are constantly learning more thanks to new technologies and ideas. We have to accept these changes and move on:
After you've done a thing the same way for two years, look it over carefully. After five years, look at it with suspicion. And after ten years, throw it away and start all over. ~Alfred Edward Perlman, New York Times, 3 July 1958I can't wait until someone redefines a neuron in a whole new way. . .