Pluto now a "dwarf planet"

An artist's conception created at the Harvard-Smithsonian Center for Astrophysics and released on January 3, 2006 shows Pluto and its moon Charon as seen from the surface of one of Pluto's newly discovered candidate satellites. Scientists may have demoted Pluto to the rank of a 'dwarf planet' on Thursday but astrologers foretell no major changes in the way they read the heavens because of the move.EDITORIAL USE ONLY NO SALES NO ARCHIVES REUTERS/David A. Aguilar/Harvard-Smithsonian Center for Astrophysics/Handout


An artist's concept shows the Pluto system from the surface of one of the moons. Pluto is the large disk at center. Charon is the smaller disk to the right of Pluto. (NASA/ESA/G. Bacon/Handout/Reuters)

An illustration based on existing astronomical observations shows Pluto's horizon spanning the foreground. Scientists from around the world on Thursday approved a new definition of a planet, downgrading Pluto's status to leave just eight classical planets. REUTERS/SwRI/NASA/Handout

In this image provided by NASA Feb. 22, 2006 from NASA's Hubble Space Telescope shows two new moons around Pluto. Leading astronomers Thursday Aug. 24, 2006 stripped Pluto of the planetary status it has held since its discovery in 1930. Pluto is in the center and Charon, the largest of Pluto's three moons, is just below it. Charon is no longer under consideration for any special designation. (AP Photo/NASA)

An image made by NASA's Hubble Space Telescope in 2005 shows Pluto and its three moons Charon, Nix and Hydra. Pluto was stripped of its status as a planet August 24, 2006 when astronomers from around the world redefined it as a 'dwarf planet.' EDITORIAL USE ONLY NO SALES NO ARCHIVES REUTERS/NASA/ESA/H. Weaver-JHU/APL/A. Stern-SwRI/HST Pluto Companion Search Team/Handout

An artist's rendition shows 12 "candidate planets", to be considered for addition to the solar system if astronomers meeting in Prague to approve a new planetary definition. Pluto has lost its seven-decade status as the ninth and outermost planet of the solar system in a decision taken by the world's top astrononomical body.(AFP/IAU/File)

Dinky Planet loses its status as planet

By WILLIAM J. KOLE, Associated Press Writer 26 minutes ago

PRAGUE, Czech Republic - Pluto, beloved by some as a cosmic underdog but scorned by astronomers who considered it too dinky and distant, was unceremoniously stripped of its status as a planet Thursday.

The International Astronomical Union, dramatically reversing course just a week after floating the idea of reaffirming Pluto's planethood and adding three new planets to Earth's neighborhood, downgraded the ninth rock from the sun in historic new galactic guidelines.
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Powerful new telescopes, experts said, are changing the way they size up the mysteries of the solar system and beyond. But the scientists at the conference showed a soft side, waving plush toys of the Walt Disney character Pluto the dog — and insisting that Pluto's spirit will live on in the exciting discoveries yet to come.

"The word 'planet' and the idea of planets can be emotional because they're something we learn as children," said Richard Binzel, a professor of planetary science at the Massachusetts Institute of Technology, who helped hammer out the new definition.

"This is really all about science, which is all about getting new facts," he said. "Science has marched on. ... Many more Plutos wait to be discovered."

Pluto, a planet since 1930, got the boot because it didn't meet the new rules, which say a planet not only must orbit the sun and be large enough to assume a nearly round shape, but must "clear the neighborhood around its orbit." That disqualifies Pluto, whose oblong orbit overlaps Neptune's, downsizing the solar system to eight planets from the traditional nine.
Astronomers have labored without a universal definition of a planet since well before the time of Copernicus, who proved that the Earth revolves around the sun, and the experts gathered in Prague burst into applause when the guidelines were passed.
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Pluto and objects like it will be known as "dwarf planets," which raised some thorny questions about semantics: If a raincoat is still a coat, and a cell phone is still a phone, why isn't a dwarf planet still a planet?

NASA said Pluto's downgrade would not affect its $700 million New Horizons spacecraft mission, which this year began a 9 1/2-year journey to the oddball object to unearth more of its secrets.

But mission head Alan Stern said he was "embarrassed" by Pluto's undoing and predicted that Thursday's vote would not end the debate. Although 2,500 astronomers from 75 nations attended the conference, only about 300 showed up to vote.

"It's a sloppy definition. It's bad science," he said. "It ain't over."

Under the new rules, two of the three objects that came tantalizingly close to planethood will join Pluto as dwarfs: the asteroid Ceres, which was a planet in the 1800s before it got demoted, and 2003 UB313, an icy object slightly larger than Pluto whose discoverer, Michael Brown of the California Institute of Technology, has nicknamed "Xena." The third object, Pluto's largest moon, Charon, isn't in line for any special designation.

International Astronomical Union

Is there beauty in asymmetry? And what are the causes of it? (This could turn into a discussion about gravity and the efficient cause of the local motion of celestial bodies... some other time.)