- WASHINGTON (CNN) -- Astronomers said Thursday they had discovered the first
solar system with multiple planets outside our own, with three massive
planets orbiting a sun-like star.
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- All three planets circling the star Upsilon
Andromeda are gas giants like Earth's big neighbor Jupiter. However, an
Earth-type planet might also be a part of this system, one researcher
said.
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- "Our observations can't rule out
Earth-sized planets as well in this planetary system, because their gravity
would be too weak for them to be detectable with present instruments,"
Peter Nisenson of the Harvard-Smithsonian Center for Astrophysics said
in a statement.
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- Astronomically, the system is not far
away: 44 light years. Its sun is so near and bright, it can be seen by
the naked eye during summer and fall.
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- Scientists have previously identified
at least 18 extrasolar planets, but this was the first time they detected
a system comparable to the nine-planet grouping that includes Earth.
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- "What we have found now, for the
first time ever, is indeed a full fledged system of planets around the
star Upsilon Andromeda," said <http://www.cnn.com/TECH/space/9904/15/new.solar.system/marcy.large.jpg
Geoffrey Marcy, professor of astronomy and physics San Francisco State
University.
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- The finding suggests that there may be
far more planets in our galaxy than previously thought, the researchers
said.
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- "When I look up at the stars now
at night I can imagine easily that every one of them has planet around
them," says Debra Fischer, a professor of physics and astronomy
at San Francisco State University.
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- Astronomers have searched for planets
outside our solar system by focusing on the behavior of certain sun-like
stars, such as Upsilon Andromeda.
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- Stars with a characteristic wobble are
believed to have a large planet orbiting around them, with enough gravity
to tug on the star.
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- Astronomers had earlier identified one
of the three planets -- the closest one to this star -- but only recently
determined that there were two others from their gravitational affect on
Upsilon Andromeda.
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- Can they support life? Scientists don't
know, because present technology is not advanced enough to determine what
the planets are made of. That, Marcy says, is astronomy's next challenge.
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- San Francisco Bureau Chief Greg Lefevre
and Reuters contributed to this report.
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