Furthest from the sun, Pluto comes under attack
PRAGUE (Reuters)
Despite being the farthest planet from Earth in our solar system,
Pluto has come under attack from astronomers and may be about to
lose its status in the battle.
Some 3,000 astronomers and scientists from around the world will
meet in Prague this week to decide whether Pluto, discovered in
1930, measures up to the definition of a planet.
In defining for the first time what exactly a planet is, the
International Astronomers Union (IAU) may be forced to downgrade
Pluto's status, or add as many as 14 others.
Such a decision would send shockwaves through the scientific
community, instantly outdate textbooks, and cause educators to
re-teach the basics of our solar system.
"The pivotal question is the status of Pluto, which is clearly very
different from Jupiter, Saturn, Uranus, and Neptune," Owen
Gingerich, professor of Astronomy and History of Science emeritus
at the Harvard-Smithsonian Center for Astrophysics told
Reuters.
Debate has raged within the scientific community over the status of
Pluto for decades after the planet was found to be only one
four-hundredths of the mass of the earth.
That discussion intensified in 2003 when astronomers at the
California Institute of Technology discovered UB 313. Nicknamed
Xena after the character in the television show, UB 313 is one of
more than a dozen celestial bodies in our solar system found to be
larger than Pluto.
Xena and Pluto are large icy bodies that reside in the Kuiper Belt
-- where thousands of floating bodies travel -- beyond Neptune.
Images from the Hubble Space Telescope put Xena's diameter at 1,490
miles or so. That is slightly bigger than Pluto, which measures
1,422 miles across.
Gingerich is the chair of a committee that was asked to come up
with a definition of a planet and hand it to the IAU general
assembly, which runs Aug. 14-25.
In the run-up to the assembly, emotions have been running high in
both directions.
Some have appealed to Gingerich's group not to downgrade Pluto,
saying it would disappoint children and throw our understanding of
the universe into chaos.
Others say let the chips fall where they may and seem to relish the
idea of overturning our current view of the universe.
Gingerich said that modern technologies have allowed scientists to
delve into the solar system further, and in more detail, than ever
before. Therefore, it is no surprise that questions on the
fundamental assumptions of it are arising.
"Should it (Pluto), for historical reasons, be considered a planet
like the rest?" Gingerich asks, refusing to tip his hand on how the
seven-member group has agreed after deciding on the wording in
June.
Scientists say the group may make a new class of planets that
accepts large bodies such as Xena and Pluto that do not measure up
to the eight larger planets. They could also drop Pluto's status as
a planet or expand the list of planets to include many
similarly-sized bodies found in the solar system.
