Maria heard her assistant’s voice halfway down the hallway. She stopped sipping her coffee to listen. Mikhail’s voice was always loud, but now it was animated. “If Tombaugh had been Russian, this wouldn’t have happened! I can’t believe American astronomers are so attached to what they think is their planet.”
Mikhail stood in her doorway. He had been out of the office for a few days. Obviously, he had just read the letter from the Division of Planetary Science (DPS) of the American Astronomical Society that Maria had left on his desk. He waved the letter with his fingertips like a soiled napkin as he spoke.
“The DPS thinks we’re reclassifying Pluto, and they strongly oppose it. I can’t believe this!” His eyes narrowed jokingly. “Plutophiles!”
The Committee on Small Body Nomenclature had received many comments about Pluto recently, especially since the Minor Planet Center completed its email poll. Professional and amateur astronomers were asked to vote on whether or not Pluto should be Minor Planet 10,000. The results of the poll indicated that the Americans were split only 51% to 49% in favor of it. However, voters in 21 other countries were 82% in favor of Pluto being Minor Planet 10,000.
Mikhail continued loudly, “You’ve seen this. They actually believe that making Pluto a Minor Planet would be interpreted as reclassifying or demoting it. They say it’s harmful to their profession. They say that acrimonious rifts are being created over this. They say there isn’t scientific or historical justification for it. Is that true?” His hand remained suspended in the air, waiting for her reply.
“Welcome back, Mikhail. Have a seat.” Maria smiled and put her cup down. Mikhail remained standing.
“Actually it isn’t,” Maria continued. “Old astronomy books have the first few asteroids classified as planets. Ceres, Pallas, Juno, Vesta—all discovered in the early 1800s—were considered planets for decades. But as more and more of these objects were discovered, they realized there were lots of bodies between Mars and Jupiter—our modern-day asteroid belt. They were all ‘demoted’ from planets and became asteroids or minor planets. But this isn’t about ‘demoting’ Pluto, just giving it minor planet status. And from our survey it looks like the majority of astronomers—except for the DPS—are OK with that.”
Mikhail took a long breath, and then blurted out: “But you know it’s so nationalistic. It’s no coincidence that the symbol for Pluto is Percival Lowell’s initials—the benefactor of the Flagstaff Observatory where Tombaugh discovered Pluto. You know they waited to announce the discovery until Lowell’s 75th birthday. What other planet was allowed to be named after a real person? There was so much hype about the ‘American planet’—even before the observatory released enough data for the International Astronomical Union to review—that when the time came to officially name it, Pluto was so well known, they had to keep the name.”
“You’re right. I won’t argue with you. They got carried away. They didn’t follow protocol. But the work was solid, and, at the time, it did look like the much-searched-for ‘Planet X,’ although now we know it wasn’t and couldn’t have been. But that’s beside the point. As more TNOs are discovered, this controversy is only going to get worse. We need a definition for the word ‘planet’ other than ‘we-know-one-when-we-see-one.’”
Mikhail looked deflated. He liked a good argument. “So … set up a meeting?”
“Right. Check everyone’s calendar, and schedule it ASAP. The agenda: respond to the DPS and begin a discussion about how to define a planet. Let’s put this Pluto issue to rest. Thanks, Mikhail. It’s good to have you back.”
Mikhail pivoted in the doorway and walked down the hall. Maria picked up her cup, but the coffee was cold. What should Pluto be called? She was beginning to call it a nuisance and was ready to close the discussion for good.
Originally published at http://www.sciencecases.org/pluto/pluto2.asp
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