Well, I’m home now. It was quite a week! I have so much I’d like to report, but to be honest I’m not feeling well. The last day of the WorldCon, I ate something which decided to poison me. I’m doing a lot better now, but Saturday was touch and go for a while. So I’ll give you some bullets here about the con, as well as other news I couldn’t keep up with due to illness, lack of an AC adapter and internet access the last day, as well as travel on Sunday:

• The WorldCon ended up being a lot of fun. I gave two talks, one TV interview, one radio interview, and sat on two panels (including one about bloggers being public intellectuals, which was interesting). I met lots of fun, friendly people, sat with authors, and hobnobbed with several Star Trek actors (more about that in a later entry). I also hooked up with Kevin Grazier, who is a scientist and the science advisor for several TV shows, including the new Battlestar Galactica! We wound up having dinner with Richard Hatch, who played Apollo on the original Galactica and has a role in the new one too. The evening was marred somewhat by a touch of food poisoning I got at lunch (two others got it as well!) but we recovered quickly enough.
• NASA will decide Monday morning how tropical storm (and potential hurricane) Ernesto will affect the Shuttle Atlantis launch. The NASA website will have updated info.
• At some point over the weekend, Saturday, I think, the BABlog had its one millionth visitor!

That’s it for now, as I’m tired. I’m sure I’ll be feeling better tomorrow, so stay tuned for my BA bloggy goodness!

On occasion (increasingly rarely these days, but still) I find myself agreeing with Bill Maher, host of a TV show called "Real Time". He’s a comedian, and used to host "Politically Incorrect", a show that was great when it was still on Comedy Central. Anyway, he had a good rant about Pluto where he described astronomers using mock Republican talking points (he called them "cut and run scientists"). A video is posted at Crooks and Liars and is worth a watch! He attacks a lot of the bad thinking that I attack on this blog as well. His language is just a touch salty, but I have to admit– it’s the first Uranus joke I’ve laughed out loud at in many, many years.

I will spare everyone my sordid tale of woe, and cut to the end: I was able to get an adapter for my laptop. I don’t have time at this moment to write any content, since I have one final obligation at the convention (I’m autographing copies of my book at 11), but afterwards, sometime this afternoon, I’m hoping to sit down and write more about what’s been going on here. I will say now that I have met or bumped into a lot of people whose work I really respect (Greg Bear, David Brin, Bjo Trimble, Joe Haldeman) and a couple of actors who are just cool (Suzie Plakson, Peri Gilpin– though not at the convention!). I’ll blog about it after I take a nap– I didn’t get back to my room until after 3:00 a.m.!

Welcome to Coast to Coast listeners! If you found me though C2C, you probably want to read this post about Pluto.

In the meantime, my laptop AC adapter is busted, and I’m running low on battery power. This happens while I’m away from home, at a convention I want to blog about, and at the same time HUGE news comes about Pluto. So I’m basically screwed here. I tried buying a universal adapter, but it had no plugs that fit! So I doubt I’ll be able to blog much until I get back home. I hope to find another computer here or even borrow an adapter long enough to get a charge, but you may not hear from me for a few days.

I hate computers.

The IAU has voted on a series of resolutions on what a planet is and what a planet isn’t, and the verdict is…

Pluto is not a planet.

At least, not a major one.

This is a big turnaround from the initial resolution, which would have given our solar system at least 12 planets, and potentially many, many more. Here is the first resolution that passed:

RESOLUTION 5A
The IAU therefore resolves that planets and other bodies in our Solar System be defined into three distinct categories in the following way:

(1) A planet is a celestial body that (a) is in orbit around the Sun, (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, and (c) has cleared the neighbourhood around its orbit.

(2) A dwarf planet is a celestial body that (a) is in orbit around the Sun, (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, (c) has not cleared the neighbourhood around its orbit, and (d) is not a satellite.

Ignoring for the moment, once again, that it’s silly to try to scientifically define a class of objects that are really only defined culturally, these definitions are still unsatisfying to me. A planet-sized object between stars is not a planet? How round is round? How do you define its "neighborhood"? These are still the same objections I made before in my earlier post about this.

But I suppose what people want to know is how Pluto fits in this. Pluto is round, and orbits the Sun, but has not cleared out its local neighborhood. Smaller objects that orbit the Sun in nearly the same orbit will get absorbed by or ejected by the larger object. As planets form, their gravity either pulls in smaller bits of junk, causing them to impact, making the planet grow, or it slingshots the smaller object away, putting it in a very different orbit. That’s why big objects in the solar system tend not to have anything else near them (except moons).

Pluto fails this. As I understand it (the news is still sketchy from the IAU meeting) there are other objects in similar orbits as Pluto, and therefore Pluto has not cleared out its neighborhood. I’m not sure if Charon, Pluto’s moon, is included in that list of uncleared objects. Now, this is a little confusing: lots of planets have moons, so just having a moon doesn’t mean a planet has not cleared its area (since the moon is bound gravitationally by the planet). But Charon orbits Pluto far enough out that the center-of-mass of the system is outside Pluto’s surface (again, see see my earlier post about this). Ironically, with the original resolution, this made both Pluto and Charon a planet. Now, under the new rules, this may mean neither is.

So: according to the new rules, passed by the IAU, Pluto is no longer a planet. I guess Neil Tyson will have to go on Colbert again.

The IAU made this pretty official with another resolution:

RESOLUTION 6A
The IAU further resolves:

Pluto is a dwarf planet by the above definition and is recognized as the prototype of a new category of trans-Neptunian objects.

This sits better with me, actually, than calling Pluto a planet, but a lot of people aren’t gonna like it.

Incidentally, there were two resolutions voted down:

Insert the word “classical” before the word “planet” in Resolution 5A, Section (1)

so that if it had passed we’d call the 8 major planets "classical". The other resolution would have been added to 6A about the dwarf planets:

This category is to be called “plutonian objects.”

Since this last bit was voted down (narrowly, 187 to 183!), the IAU will decide what to call this class of objects at the next meeting, in Rio in 2009. Rio, hmmmm… maybe I’d better go to that one.

Let me once again reiterate that trying to define what a planet is is very, very silly. The very fact that all this is so bizarrely confusing is good evidence of this.

Want another reason this is silly? If the reason Pluto isn’t a planet is because of Charon, then we’re in trouble: as I pointed out in my other post, in a billion years or so the Moon will be far enough away that the Earth-Moon center-of-mass will be outside the Earth. So at that time, if I understand this correctly (and I may not), Earth will no longer be a planet. I need to find out more about all this, but as I said, details about why exactly Pluto isn’t a planet anymore are still a little sketchy. I’ll post more when I find out.

And here’s another point. Pluto crosses Neptune’s orbit. Due to the delicate dance of gravity between the two, they never actually get near each; Pluto is always on the opposite side of the Sun from Neptune when it crosses the bigger planet’s orbit. So, if Pluto’s orbit actually overlaps Neptune’s, doesn’t that mean Neptune hasn’t cleared out its neighborhood? I think you might argue that. So why don’t we have 7 planets?

I’m really torn over this. Scientifically, this whole debate is a tempest in a teapot. It’s ridiculous, and serves no purpose. How is scientific knowledge furthered in any way by debating and resolving this?

On the other hand, it’s gotten a lot of interest by the public, and it’s been positive interest so far. People are talking about what it means to be a planet, and given the abysmal level of science education in the US, it’s great that folks are actually talking about astronomy. Maybe it’ll lead to some of them looking into it more, and that’s a good thing.

And now, finally, just maybe, we can actually get back to studying these objects instead of arguing about what to call them. There’s much to learn about them, real stuff, interesting stuff. The planets — however many you may think there are — are waiting. Let’s get going.

I am at WorldCon! This is the first day of the con, so I suspect there will be more people tomorrow, but there were still quite a few today. The dealer room was a little crowded, but of course these guys didn’t help:

This is an amazing display of model building. Robbie the Robot even moves, lights up, and has audio from "Forbidden Planet"! And if you don’t know what that movie is, go and rent it. It’s a classic science fiction piece from the 50s. Leslie Nielson is the handsome hero. Seriously. It’s a great flick. That’s the fembot from "Metropolis" next to Robbie.

Anyway, I’ve run into a handful of people I know, including Rick Sternbach, who signed my copy of the Star Trek Compendium:

I am such a huge geek fanboy. But there you go. Anyway, I’m giving my general Bad Astronomy talk tomorrow (I make fun of Trek a little bit in it) and I hope I get a nice audience. There’s a pseudoscience panel scheduled at the same time. Sigh. Later I’m on a panel about science as well, so it’ll be a fun day.

Bob Naeye (it’s pronounced "Noy uh") is many things: an astronomer, an editor, a writer, and a friend. He used to work for Astronomy magazine but then wised up and moved on, working for some time at Mercury magazine, and now has settled in at Sky and Telescope.

The folks there were smart enough to give Bob his own blog, called Bob’s World of Astronomy, a name I find pretty funny. I don’t know why they used such a bizarre URL, and didn’t use more common blogging software like WordPress, so at some point I’ll talk to the folks at S&T and make fun of them ask them about that.

Anyway, Bob has an unusually lucid outlook on things astronomical (even when we sometimes disagree, I always have to concede he makes a good point — it’s just that mine is better), so you should give it a read.

P.S. I am flying to L.A. today for the WorldCon, so I’ll probably be posting lightly until this evening. After that, I’ll try to squeeze as much mo’blogging in as I can!