Wednesday, January 06, 2010
What Happened to Pluto?
We visited the Museum of Science in Boston over the Christmas break, mostly to see the Harry Potter Exhibit (more on another post!), but we also had the opportunity to see the very last showing of "What Happened to Pluto" at the Hayden Planetarium. The planetarium will be closed for renovations for a whole year.
When they interviewed people on whether they felt Pluto should remain a planet, invariably the older generations said Yes! and the younger generations said no. I can't let go of the planet mnemonic "M VEM J SUN P" so I guess that puts me with the old fogies. Dova resoundingly said that Pluto was NOT a planet when I asked her. During the show, I even learned a new mnemonic, "My very excellent mother just sent us nine pizzas". According to Urban Dictionary, since Pluto is no longer considered a planet, you'll have to use "My very erotic master just showed up naked." Oops! This is a family blog!
I remember the hubbub about downgrading Pluto's status as a planet back in 2006, but I didn't understand the details until I read this children's book, The Planet Hunter: The Story Behind What Happened to Pluto. (Sometimes science is best explained by children's books, even for this engineer.)
So what happened to Pluto's status? The Planet Hunter describes astronomer Mike Brown's quest to find planets ever since he was a boy. After many years of searching, he finally found planet-like objects in the icy Kuiper belt. In 2007, he and colleagues determined that one object, Eris (formerly UB313), was actually heavier than Pluto. The International Astronomical Union (i.e. egghead group of astronomers) finally put more requirements into the definition of a planet, which left poor Pluto out. Pluto and other orbiting objects like Eris are now considered dwarf or minor planets. There's even a planet named Santa because it is round and fat. It's much easier to understand with cool names and illustrations!
But it will be a while before all the textbooks and displays of the solar system are updated. It will be so flat and boring without that tilted elliptical orbit!