As far as I’m concerned, Pluto is — and will always be — a planet. I don’t at all dispute the 2006 decision of the IAU (International Astronomical Union) to classify planets in a way that excludes Pluto (and a lot of other rocks out there). Clearly without that classification, we’d end up with hundreds of new planets. I’m just saying that Pluto gets honorary planet status; it gets “grandfathered in” as one of the original nine.
Why am I writing about this now? Well, it came up in a (real world) discussion recently, so it’s on my mind. The reason it came up was due to a discussion about the New Horizons space mission, which will visit Pluto (the planet) in July of next year — a mere 190 days away. We’ve been waiting since January of 2006 — over eight years!
And I’m not alone in insisting on Pluto’s planetary status; far from it!
New Mexico’s House of Representatives, in 2007, passed a resolution that Pluto will always be considered a planet in New Mexico skies. (Just one more reason to love New Mexico.) They did this in honor of Clyde Tombaugh, who discovered the planet in 1930. I’ll say more about him and his discovery in a moment.
The Illinois State Senate passed a similar resolution in 2009. Tombaugh was born in Illinois. (Incidentally, if you’re wondering why pennies still exist, despite their complete uselessness and costing more than a penny to make, blame Illinois — birthplace of Abraham Lincoln.)
And in a debate at Harvard University just this fall, the audience voted in favor of an initiative to reinstate Pluto as a planet.
Astronomers can have all the dwarf planets they want. They can even refer to Pluto as — technically speaking — a “dwarf planet” if that makes them happy. But in our hearts, let’s face it: Pluto is, now and forever, a planet.
Clyde Tombaugh discovered Pluto (the planet) on February 18, 1930, and the discovery of a ninth planet (yes, planet, damn it) made world-wide headlines.
The Lowell Observatory, where Tombaugh worked, and which had the naming rights to the new planet, received more than a thousand suggestions on what to call it. Lowell’s wife, Constance, suggested Zeus, Percival and even Constance. These suggestions were — fortunately — ignored.
Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune… and Constance?
Or worse: Percival!
On March 24, 1930, members of the Lowell Observatory voted among Minerva, Cronus and Pluto. The name we now know it as — Pluto (the planet) —received very vote. Venetia received GB£5 (five pounds — equivalent to £276 today — or just shy of $450 (USD) — not a bad reward for an eleven-year-old).
Some think the planet was named after Disney’s famous dog. In fact, if anything, it’s the other way around (and possibly there is no connection at all).
The Disney dog first appeared, in The Chain Gang, as an unnamed dog in 1930 where he appeared as a bloodhound tracking Mickey (an escaped convict). Less than two months later, he appeared as Minnie’s dog, Rover. By his third appearance (The Moose Hunt), in 1931, he is Mickey’s dog and has the name we know today.
Some believe Walt Disney capitalized on the new planet’s name, and it’s hard to see why that name would have been picked otherwise. There is a certain alliteration to “Pluto the pup,” but the timing does suggest a connection.
Incidentally, some of Clyde Tombaugh’s ashes are riding out to Pluto (the planet) on the New Horizons spacecraft! How cool is that? (Very cool. It’s really cold out there!)
So that’s the deal. The IAU decision is a fine one that we can apply to all other Pluto-like rocks. But Pluto gets honorary planet status now and forever.
At least in my heart, and I hope in yours.
To play you out, a tune by a favorite artist of mine, David Gray. There’s no connection between his song and the Pluto (the planet) mission, but the titles are the same. (And, in general, I’m a fan of new horizons.)