Bad Astronomy

The unbearable roundness of being

[UPDATE: The article discussed below is now online at Discover Magazine’s website, so you can read it there.]

Every now and again I delve back into the ancient art of writing for an actual magazine that has words printed in ink on paper which gets sent to you via the postal service.

Quaint, I know.

discovermag_dec2010coverBut I wrote just such an article for Discover Magazine which is in the December 2010 issue. The article, called “Why Size Matters” is about why defining the word planet is proving to be so difficult.

Funny how writing works sometimes. I got the idea for the article while researching a blog post on a moon in the outer solar system. Curious about its size, I started poking around the web looking for other moon diameters, and then started wondering how big an object you need before gravity crushes it into a ball. I thought I could write the article about just that, but the words apparently had a mind of their own and went in a different direction. I wound up talking about what we think of as planets, and then in the middle of all this I read an advance copy of Mike Brown’s wonderful book How I Killed Pluto and Why It Had It Coming (full review coming soon). Mike spends quite a bit of time on this very topic, as you might imagine (he discovered the Kuiper Belt object Eris, which kick-started the demotion of Pluto). I found his thinking to be very similar to mine, and his writing actually gelled a lot of disorganized thoughts I had about all this.

Anyway, the article was fun to write, and I think anyone who likes my blog will like it. I got the issue in the mail the other day, and it’s on newsstands and at bookstores now. I hope you’ll check it out.