Dogged! Pluto Stripped of Planetary Status
Christine Lavin’s folk albums have been enjoyed in our house since before my oldest child was born. Of course, if you aren’t familiar with the singer, you may well wonder why her name opens an article purporting to discuss the latest news about Pluto. (You know – that heavenly body formerly known as a planet.) It’s not a complicated story really, but a little background information might help.
It all started back in 1996 when Lavin wrote a song entitled Planet X, her musings sparked by a USA Today article about the controversy surrounding Pluto’s planetary status. After a brief rhyming history of Pluto’s discovery and the scientific arguments over its importance, she asked the question,
But how are we going to deal with it
if science comes up with the proof
that Pluto was never a planet.
How do we handle this truth?
As the PhD’s all disagree
we don’t know yet who’s wrong or who’s right
but wherever you are, whatever you are,
Pluto, we know you’re out there tonight.
We found the song (and the question) amusing, but we never really expected events to come to a head as they did this week when Pluto’s status was decided once and for all at a meeting in Prague of the International Astronomical Union. This, apparently, is the body that sets standards for the field of astronomy, which means they have always had the power to demote Pluto to a lowly Kuiper Belt object (KBO), Trans-Neptunal object (TNO), or even a “Plutino.” Plutinos, by the way, are objects that orbit the sun beyond Neptune. Most are much smaller than Pluto and are believed to be similar to comets, but they are defined by orbital patterns which resemble Pluto’s. This of course makes it all a bit confusing. How does one imagine classifying Pluto among its own namesakes? And incidentally, are they going to have to rename plutonium now?
More to the point, why does the International Astronomical Union even care? Why all the fuss over a tiny frozen planet whose only real value to the universe was (thanks to a little help from Walt Disney) its ability to capture the imaginations of school-children on a planet more sure of its status a couple of billion miles away?
The truth is that Pluto was beginning to make the solar system seem a bit more complicated than the average astronomer likes. As more and more “bodies” are making themselves known at the edges of our solar system, Pluto has begun looking less and less like another planet, and more and more like the rest of the non-descript and far-flung debris littering space. This has resulted in increasing scientific disdain for the ninth planet, despite the fact that new discoveries reveal Pluto has at least three of its own moons—a distinction that would give any of the rest of us a great deal of personal significance. Nevertheless, astronomers began to think that if they allowed Pluto to join the planetary club, the door might have to be opened to dozens or even hundreds more. At the very least, they would certainly have to admit a tenth body discovered last year which is even further from the sun than Pluto but seems to be slightly larger and has been popularly nicknamed “Xena.” As long ago as 1996, Christine Lavin could see where all this was going:
and now 20 astronomy textbooks
refer to Pluto as less than a planet
I guess if Pluto showed up at a planet convention
the bouncer at the door might have to ban it.
On the other hand, the International Astronomical Union may have done Pluto a good turn. If the IAU had given Pluto the thumbs up and with it hundreds of other “planets,” one might imagine the beleaguered entity responding in Groucho Marx style, with the words:
“Please accept my resignation from the solar system. I don’t care to belong to any club that will have me as a member.”