1887Solar system loses a planet
- Aug 24, 2006http://news.yahoo.com/s/ap/20060825/ap_on_sc/planet_mutiny
Dinky Pluto loses its status as planet
By WILLIAM J. KOLE, Associated Press Writer 1 hour, 20
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
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.
The shift will have the world's teachers scrambling to
alter lesson plans just as schools open for the fall
"It will all take some explanation, but it is really
just a reclassification and I can't see that it will
cause any problems," said Neil Crumpton, who teaches
science at a high school north of London. "Science is
an evolving subject and always will be."
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.
Predictably, Pluto's demotion provoked plenty of
"It's disappointing in a way, and confusing," said
Patricia Tombaugh, the 93-year-old widow of Pluto
discoverer Clyde Tombaugh.
"I don't know just how you handle it. It kind of
sounds like I just lost my job," she said from Las
Cruces, N.M. "But I understand science is not
something that just sits there. It goes on. Clyde
finally said before he died, 'It's there. Whatever it
is. It is there.'"
The decision by the IAU, the official arbiter of
heavenly objects, restricts membership in the elite
cosmic club to the eight classical planets: Mercury,
Venus, Earth, Mars, Jupiter, Saturn, Uranus and
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
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
Brown, whose Xena find rekindled calls for Pluto's
demise because it showed it isn't nearly as unique as
it once seemed, waxed philosophical.
"Eight is enough," he said, jokingly adding: "I may go
down in history as the guy who killed Pluto."
Demoting the icy orb named for the Roman god of the
underworld isn't personal it's just business said
Jack Horkheimer, director of the Miami Space Transit
Planetarium and host of the PBS show "Star Gazer."
"It's like an amicable divorce," he said. "The legal
status has changed but the person really hasn't. It's
just single again."
AP Science Writers Alicia Chang in Los Angeles and
Seth Borenstein in Washington, and correspondents Sue
Leeman in London and Mike Schneider in Cape Canaveral,
Fla., contributed to this story.
On the Net:
International Astronomical Union, http://www.iau.org
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