Grant B
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A new planet we won't explore!
Frozen world beyond Pluto's orbit is largest solar system find in 72 years
Mon Oct 7, 1:09 PM ET
By ANDREW BRIDGES, AP Science Writer
LOS ANGELES - A billion miles beyond Pluto, astronomers have discovered a
frozen celestial body 800 miles across (1,287 kilometers) - the biggest find
in the solar system since the ninth planet was spotted 72 years ago. But
astronomers do not consider the newfound object a planet.
The object is about one-tenth the diameter of Earth and orbits the sun once
every 288 years at a distance of 4 billion miles (6 billion kilometers). It
is only half the size of Pluto, which some astronomers have come to believe
should not have been designated a planet at all.
Planetary astronomer Michael Brown of the California Institute of Technology
in Pasadena and postdoctoral scholar Chadwick Trujillo discovered the object
in images taken June 4. They were to announce their discovery Monday in
Birmingham, Alabama, at a meeting of the American Astronomical Society's
division of planetary sciences.
"It's about the size of all the asteroids put together, so this thing is
really quite big," Brown said.
The two used a telescope at the Palomar Observatory near San Diego to
discover the world, provisionally dubbed Quaoar (pronounced kwah-o-wahr), a
creation force in Southern California Indian mythology. Follow-up
observations with the Hubble Space Telescope confirmed its size.
Archival research showed Quaoar had been captured on film as long ago as
1982, but was never noticed, Brown said. He and Trujillo went back and pored
over the older images to help pin down the circular path it travels around
the sun.
"It could easily have been detected 20 years ago, but it wasn't," Brown
said.
Quaoar lies in the Kuiper Belt, a swarm of objects made of ice and rock that
orbit the sun beyond Neptune. The objects are considered fossil remnants of
the swirling disk of debris that coalesced to form the solar system roughly
5 billion years ago. It is also believed to be the source of some comets.
The belt contains as many as 10 billion objects at least one mile across;
astronomers estimate five to 10 of those are jumbo-sized.
"This new discovery fits right in with our expectation that there should be
a handful or two of objects as large as Pluto," said astronomer David Jewitt
of the University of Hawaii. Jewitt, with then-colleague Jane Luu,
discovered the first Kuiper Belt object just a decade ago.
As larger Kuiper Belt objects turn up, the case for Pluto as a planet
weakens, astronomers said. Pluto lies within the Kuiper Belt and is
considered by many merely among the largest of the bunch, and not a planet
in its own right.
"It's pretty clear, if we discovered Pluto today, knowing what we know about
other objects in the Kuiper Belt, we wouldn't even consider it a planet,"
Brown said.
Astronomers expect yet-undiscovered Kuiper Belt objects may rival even
Pluto.
"An observation like this just confirms that, that we may discover Kuiper
Belt objects bigger than Pluto," said Frank Summers, an astrophysicist at
the Space Telescope Science Institute in Baltimore.
NASA is considering launching a spacecraft to explore Pluto, its moon,
Charon, and at least one Kuiper Belt object, but whether it will be funded
remains unclear. The New Horizons mission could launch as early as 2006, and
would take about a decade to reach Pluto.
Frozen world beyond Pluto's orbit is largest solar system find in 72 years
Mon Oct 7, 1:09 PM ET
By ANDREW BRIDGES, AP Science Writer
LOS ANGELES - A billion miles beyond Pluto, astronomers have discovered a
frozen celestial body 800 miles across (1,287 kilometers) - the biggest find
in the solar system since the ninth planet was spotted 72 years ago. But
astronomers do not consider the newfound object a planet.
The object is about one-tenth the diameter of Earth and orbits the sun once
every 288 years at a distance of 4 billion miles (6 billion kilometers). It
is only half the size of Pluto, which some astronomers have come to believe
should not have been designated a planet at all.
Planetary astronomer Michael Brown of the California Institute of Technology
in Pasadena and postdoctoral scholar Chadwick Trujillo discovered the object
in images taken June 4. They were to announce their discovery Monday in
Birmingham, Alabama, at a meeting of the American Astronomical Society's
division of planetary sciences.
"It's about the size of all the asteroids put together, so this thing is
really quite big," Brown said.
The two used a telescope at the Palomar Observatory near San Diego to
discover the world, provisionally dubbed Quaoar (pronounced kwah-o-wahr), a
creation force in Southern California Indian mythology. Follow-up
observations with the Hubble Space Telescope confirmed its size.
Archival research showed Quaoar had been captured on film as long ago as
1982, but was never noticed, Brown said. He and Trujillo went back and pored
over the older images to help pin down the circular path it travels around
the sun.
"It could easily have been detected 20 years ago, but it wasn't," Brown
said.
Quaoar lies in the Kuiper Belt, a swarm of objects made of ice and rock that
orbit the sun beyond Neptune. The objects are considered fossil remnants of
the swirling disk of debris that coalesced to form the solar system roughly
5 billion years ago. It is also believed to be the source of some comets.
The belt contains as many as 10 billion objects at least one mile across;
astronomers estimate five to 10 of those are jumbo-sized.
"This new discovery fits right in with our expectation that there should be
a handful or two of objects as large as Pluto," said astronomer David Jewitt
of the University of Hawaii. Jewitt, with then-colleague Jane Luu,
discovered the first Kuiper Belt object just a decade ago.
As larger Kuiper Belt objects turn up, the case for Pluto as a planet
weakens, astronomers said. Pluto lies within the Kuiper Belt and is
considered by many merely among the largest of the bunch, and not a planet
in its own right.
"It's pretty clear, if we discovered Pluto today, knowing what we know about
other objects in the Kuiper Belt, we wouldn't even consider it a planet,"
Brown said.
Astronomers expect yet-undiscovered Kuiper Belt objects may rival even
Pluto.
"An observation like this just confirms that, that we may discover Kuiper
Belt objects bigger than Pluto," said Frank Summers, an astrophysicist at
the Space Telescope Science Institute in Baltimore.
NASA is considering launching a spacecraft to explore Pluto, its moon,
Charon, and at least one Kuiper Belt object, but whether it will be funded
remains unclear. The New Horizons mission could launch as early as 2006, and
would take about a decade to reach Pluto.
