“Mama!” her oldest son hollered from the kitchen, “it’s that reporter again. He wants to know about the Internet vote on Pluto.”
Maria expected the call but was still annoyed at its timing. She popped the last bite of pie into her mouth as she weaved her way through the overcrowded dining room into the messy kitchen.
“Hey, Dr. Ocasio. It’s Jamar Rogers from Boston Science Monthly. How you doing? I hate to bother you—I can hear you’re busy—but we go to press soon and I was wondering if you could give me an update on Pluto.”
As the chair of the Committee on Small Body Nomenclature of the International Astronomical Union, Dr. Maria Ocasio was in charge of naming small bodies in the solar system. She also worked closely with the Minor Planet Center at Harvard University, where astronomical data for asteroids and comets are collected, computed, checked, and disseminated. As their orbital parameters are determined, these small bodies are assigned minor planet numbers. Last month, 158 new asteroids were numbered. This week they had confirmed the orbital characteristics of an asteroid commonly known as “Ehrenfreund,” officially making it Minor Planet 9826. There was now a buzz about assigning the number 10,000 to Pluto.
The reporter continued: “I heard that the Minor Planet Center will be up to 10,000 and are suggesting giving that to Pluto. I’ve even heard they’re voting to demote Pluto to a minor planet. That sounds pretty unscientific to me! What’s your position?”
“Nobody’s demoting Pluto. However, we’re curious about what the community thinks,” Maria explained, as she brushed bread crumbs off a chair before sitting down. “When Clyde Tombaugh discovered Pluto in 1930, most people thought it was a planet. But now we know Pluto isn’t alone. Now we know about a hundred other objects orbiting beyond Neptune—called Trans-Neptunian Objects, or TNOs. They’re catalogued as minor planets. Why not Pluto? What makes it special? Why not award Pluto a ‘dual status’— minor planet 10,000 and the 9th planet? Or maybe we should call it a comet? What do you think?”
“Hey, wait a minute!” Jamar laughed. “I’m the one who’s supposed to be asking the questions. So, is Pluto a comet?”
A sprinkling of frost glittered inside the window above the sink. Maria sighed. “After Pluto was at perihelion—its closest approach to the Sun in 1989—its icy surface warmed and it developed a very tenuous atmosphere. That’s what comets do—except they get a lot closer to the Sun and have huge, extended atmospheres. But Pluto never gets much closer to the Sun than Neptune. Its orbit isn’t eccentric enough to be a comet. It sounds redundant, but Pluto is just one of many Plutinos.”
“Plutinos?” interrupted the reporter. “What are they?”
“Plutinos are a family of TNOs whose orbits are linked to Neptune. They make two complete orbits in the same time it takes Neptune to make three. That’s called orbital resonance, and it keeps them from colliding with Neptune. So far, Pluto is the largest Plutino.”
Maria could hear murmuring and rustling of pages over the receiver. The reporter caught up and replied, “That’s good info. Thanks. One more thing. I’ve got Clyde Tombaugh’s biographer saying that demoting Pluto would be extremely disrespectful to his widow. You know Tombaugh died two years ago, in ’97. This biographer is very pro-Pluto. He said,—and I’m quoting here—‘this whole referendum thing isn’t about science, it’s about people.’ Do you have a comment about that?”
Maria’s youngest daughter poked her head into the kitchen and announced: “Mama! Marcos is telling that story I told you about when his pig got out and the neighbors called the police. You gotta hear it, it’s really funny.”
Maria smiled and replied softly, “I won’t be long.”
“What? Did you say he is wrong?” the reported cried.
“No, no,” Maria said into the phone. “Tombaugh is the great, hard-working American success story. He discovered Pluto before he even went to college. But as more and more TNOs were discovered, I think he began to see the writing on the wall.”
“OK, one more thing,” Jamar said. “NASA is proposing a robotic mission to Pluto—the Pluto Express. Do you think it will lose funding if Pluto is no longer a planet?”
Maria had spent the last 19 years studying asteroids and comets. To her, the tiniest one was worthy of funding and research. These bodies represented the primordial solar system and held clues to its formation. If Pluto was a rose by any other name, it would still smell as sweet to her and her colleagues at NASA.
“I’m not worried,” she said. “If Pluto Express isn’t funded, it won’t be because of this.”
“All right. One more thing,” the reported repeated. “If Pluto was demoted to a minor planet, wouldn’t you feel bad for the kids of America? I mean, kids like Pluto. I sure did. Still do!”
Maria rolled her eyes and caught site of her children’s finger paintings yellowing on the fridge. “Well, yeah, kids like Pluto, but …”—loud guffaws and shrieks of laughter erupted from the next room—“… but let’s see how the opinion poll goes, Jamar. Then after the Committee meets again we’ll have something for you. But that’s all for tonight.”
After saying their goodbyes, Maria hung up. The laughter in the next room subsided. She rubbed her forehead and then her eyes with both hands. Who would have thought a name mattered so much?
Date Posted: 03/21/05 nas
Image Credit: Title graphic based on a Hubble Space Telescope image of Pluto and its satellite Charon, courtesy of the National Space Science Data Center.
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