How I Killed Pluto and Why It Had It Coming - Mike Brown [56]
I went home that night and told Diane about the methane.
“So it’s a planet?” she said.
“No,” I quickly pointed out. “It means Pluto is not a planet.”
“But if there are only two of them out there that look like this, and they both look different from everything else, why not just call them both planets?”
I went over my usual litany: Pluto was simply the largest—now the second largest!—member of a huge population in the Kuiper belt. Singling it out for special planetary status really made no sense at all.
“Okay, but think about your daughter.”
Huh?
“Having her father discover a planet might mean that someday she’ll be able to afford college.”
Diane was joking. At least mostly.
I remained adamant.
She pressed: “Didn’t you used to joke that your definition of a planet was ‘Pluto is not a planet, but anything that I find that’s bigger is’?”
Yes. I had made that joke. But it was a joke.
Diane was in her energetic superwoman second trimester. If I was working late trying to figure out something about Xena or Santa, she would stay awake even later looking at baby magazines. If I woke up early to try to look at a few pictures of the sky just as they were coming off the telescope, she would already be awake looking at pregnancy books. As long as she was fed, she was unstoppable.
“But really, you are going to have people arguing that it is a planet, and you’re going to stand up and say, ‘No no no no’? If Petunia is a really cute child, will you go around and point out that, really, she is not so cute because, well, her nose is a bit big?”
Well, only if it is big.
“Don’t you think it would overall be better for astronomy to have new planets discovered rather than have old planets killed?”
I think it’s better to get it right.
“But don’t you think the public would be more excited and engaged in astronomy and in science if there were new planets being discovered?”
Enough, woman who needs no sleep! It is past my bedtime! But I will ponder your suggestions in the morning when I wake up, which will be long after you’ve already risen.
As winter waned to spring, three independent trains of thought ran through my mind. If I ever got to spend more than a few hours in a row thinking about one of them, I would suddenly sit up with a start and remember one of the others and start thinking about that one, before I suddenly remembered the third, and then the process would start all over again.
The first ticking calendar was strictly biological. Petunia was getting bigger. Her bones were hardening. Her eyebrows were growing. She had a July 11 due date, and though there was not much I could do to influence anything, I could nonetheless obsess about what, precisely, a due date means. I asked anyone who I thought might have some insight. I know, for example, that due dates are simply calculated by adding forty weeks to the start of the mother’s last menstrual cycle. But how effective is that? How many babies are born on their due dates?
Our child-birthing class teacher: “Oh, only five percent of babies are actually born on their due dates.”
Me: “So are half born before, half after?”
Teacher: “Oh, you can’t know when the baby is going to come.”
Me: “I get it. I just want to know the statistics.”
Teacher: “The baby will come when it is ready.”
I asked an obstetrician.
Doctor: “The due date is just an estimate. There is no way of knowing when the baby will come.”
Me: “But of your patients, what fraction delivers before, and what fraction delivers after the due date?”
Doctor: “I try not to think of it that way.”
I propose a simple experiment for anyone who works in the field of childbirth. Here’s all you have to do. Spend a month in a hospital. Every time a child is born, ask the mother what the original due date was. Determine how many days early or late each child is. Plot these dates on a piece of graph paper. Draw a straight line