Two planets, a star, and a solar system
WASHINGTON (AP) - February 14, 2008 The simultaneous discovery of two planets is rare and this was
the first time researchers had the opportunity to do so using a
technique called gravitational microlensing.
"You could call it luck, but I think it might just mean that
these systems are common throughout our galaxy," said Scott Gaudi
of Ohio State University, lead author of the report in Friday's
issue of the journal Science.
The star and its planets were observed when they passed in front
of a more distant star in 2006. A lensing effect magnified the
light of the distant star 500 times, the researchers explained.
Gaudi analyzed the data and discovered a distortion that he
thought was caused by a Saturn-mass planet. Then, less than a day
later, came an additional distortion he wasn't expecting: a
"blip" in the signal that appeared to be caused by a second,
larger planet orbiting the same star.
It took two months to confirm the two-planet find. David
Bennett, a research associate professor of astrophysics and
cosmology at the University of Notre Dame, refined the preliminary
model revealing additional details about the system.
The researchers said the newly discovered planets appear to be
gaseous, like Jupiter and Saturn, but only about 80 percent as big.
"This is the first time we had a high enough magnification
event where we had significant sensitivity to a second planet - and
we found one," Gaudi said in a statement.
Four single planets have been found previously using
microlensing, two of them by the Ohio State University-based
Microlensing Follow Up Network - MicroFUN.
This work was funded by the National Science Foundation; NASA;
the Polish Ministry of Scientific Research and Information
Technology; the SRC Korea Science & Engineering Foundation; the
Korea Astronomy & Space Science Institute; German Research Council;
Particle Physics and Astronomy Research Council; the European Union
Program for Research and Technological Development; the Israel
Science Foundation; the Marsden Fund of New Zealand; the Japan
Ministry of Education, Culture, Sports, Science and Technology and
the Japan Society for the Promotion of Science.
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