A long time ago, at a conference far far away in Prague, the International Astronomical Union designated Pluto as a “dwarf planet.”
Most people moved on, but not Arizona state Rep. Justin Wilmeth (R-Phoenix). His office is chock-full of Pluto merch from posters and T-shirts to books and a mug.
Wilmeth is a self-described history and space geek who sponsored a bipartisan bill to make Pluto Arizona’s official planet this year. Gov. Katie Hobbs signed that bill into law, making Pluto the state’s official planet.
“Twenty years from now, I might be known for a couple of things, but Pluto is going to be one of them and I pull no punches on that. I'm proud of it. I think it's important in its own way,” Wilmeth said.
Pluto was discovered in Flagstaff, Arizona, in 1930 by Clyde Tombaugh.
Lowell Observatory in Flagstaff was founded by an astronomer, Percival Lowell, who always speculated about a ninth planet which he called “Planet X.” Lowell didn’t find it in his lifetime, but the observatory remained.
Fourteen years after Lowell’s death, Tombaugh discovered Pluto by comparing two photographic plates, each displaying the same tiny fraction of the night sky several days apart.
He detected that one thing seemed to have shifted.
“The technology in our pockets is more powerful than what was used to discover something 4 billion miles away in 1930 in Flagstaff, AZ. If that's not worth mentioning, then I don't know what to tell you,” Wilmeth said.
All other planets were first cataloged in Europe. The astonishing American discovery ignited the world. Classrooms started teaching the 9-planet model, Disney renamed Mickey’s pet dog. But just 76 years later it all came crashing down.
Kevin Schindler is a historian at the Lowell Observatory. His office is an even bigger shrine to the planet in question, including cans of Pluto-themed beer. He runs the “I Heart Pluto” festival every year — named for a heart-shaped splotch on Pluto’s side — where various businesses participate in Pluto-themed events.
“The controversy, I think, has been great, because it keeps in the public eye,” Schindler said. “Like Uranus and Neptune? Nobody cares about them. But Pluto, boy, don't take our planet away. It's funny. I mean, we still get visitors saying, you know, are you guys OK? They took your planet away.”
The issue of Arizona being “slighted” has created a bit of conspiracy theory that riled up some legislators.
They say jealous Europeans, upset that America had discovered a planet, hatched a plot to take it away when most conference members had gone home.
“When Pluto was deprived of his planetary status, the people who were disenfranchised were Arizona voters. … Now in 2006, scientists also had a problem. They had discovered a 10th planet. Now those of us who are normal people, we know how to count to 10, but that was too many for their tiny little scientist brains to handle,” Rep. Alexander Kolodin (R-Scottsdale) said.
“The IAU waited until the American delegation had gone home and then under cover of night, they de-planeted Pluto,” Kolodin continued. “It is time to end this failed system of unelected bureaucrats exercising power over our society and stick it to the Pluto deniers.”
Italian Astrophysicist Piero Benvenuti is General Secretary of the IAU. Of the European-jealousy theory, he described it as “total stupidity.”
Benvenuti says the only people in the world who still ask him to restore Pluto’s planetary status are from the United States.
“No one in the world is caring about Pluto being a dwarf planet, but only the U.S. and in particular Arizona,” Benvenuti added.
Two bodies were discovered in the solar system in addition to Pluto that raised the question of what can be constituted a planet, and where scientists should draw the line: Ceres and Eris.
Eris, named appropriately by the IAU after the Greek goddess of strife, was discovered in 2005 in an off year where the IAU doesn’t meet. Eris is now classified as a dwarf planet. It’s smaller and further from the Sun than Pluto, but it’s heavier.
Ceres was discovered before Eris and is closer to the Sun than both Eris and Pluto, but it was discovered at a time when scientists believed all planets had to be spaced a certain distance from one another. That theory has since been disproven.
Scientists were faced with adding more and more planets to the solar system, or making a change.
Under the IAU’s adopted planetary definition, Ceres and Eris are also characterized as “dwarf planets.”
There are some other alternative theories about why that vote happened in 2006, toward the end of the two-week conference when most of the planetary astronomers had already left.
The IAU does have more than 12,000 members. But only a few thousand come to conferences, and only a few hundred people voted on the planetary definition that knocked Pluto out of the lineup.
Some astronomers argue the vote was political, but Lowell Stellar Astronomer Gerard van Belle says it was personal. He’s an IAU member who voted against changing Pluto’s status in 2006.
“So, I wouldn't say that it was a kind of a nationalistic rivalry. I would say it was a much more kind of petty personal rivalry between individual astronomers and people who wanted to make their mark,” van Belle said.
He says the IAU made an error by drifting into crafting scientific definitions.
“For example, I can tell you what a distance is, and I can tell you that an astronomical unit is this long or a meter is this long, but if I try to tell you what is a ruler; a ruler could be many things. And if I try to say a ruler has to be exactly this, I've sort of drifted into philosophy and less away from physics,” van Belle said. “They have never come back to revisit any such similar questions, and so it was kind of motivated by, I think, kind of personal agendas for starters.”
He also noted that some of the types of astronomers who voted probably shouldn’t have been the ones to decide.
Will Grundy works at Lowell Observatory as a planetary astronomer — ironically, a profession that largely didn’t vote on the planetary definition. He is also the leader of the New Horizons mission’s surface composition team.
“Most of the planetary science community sort of looked over our shoulder at the IAU and shrugged and said ‘um, we're the planetary scientists. You can come and talk to us about it if you really need to know about that,’” Grundy said.
In the end, Wilmeth said he doesn’t want to argue about scientific definitions, he wants the new law to get people interested in space and shine a light on Arizona.
He also isn’t stopping with the Pluto bill.
He’s also sponsoring legislation to establish a Space Commission in Arizona. He says it’s his job to be a little bit visionary.
“We can do anything in this state and in 400 years when we have a manned mission to Pluto, there better be an Arizonan on it,” Wilmeth said.