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Two groups of astronomers were able to capture first pictures of planets outside our solar system.
Three of them form a multi-planet system, very similar to ours, orbiting a star, scientists said that two studies published in the journal Science.
Although in the past has been much talk about the existence of "exoplanets" (beyond our solar system), this is the first photographic evidence that proves it.
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Plot of three planets orbiting the star HR8799 discovered by ground-based telescopes.
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So far, two groups of scientists have released images of four planets and say it could be many more, but still have not managed to see them.
The first team of the University of California, Berkeley (who used the Hubble Space Telescope) managed to capture the image of a planet orbiting a star 25 light years from Earth.
it is believed that the star is cooler and less massive than has been seen outside our solar system.
The second team, Herzberg Institute of Astrophysics in Canada, the Lowell Observatory and Lawrence Livermore National Laboratory in the U.S. (which used the Keck and Gemini telescopes on the ground in Hawaii), managed to obtain infrared images of three planets orbiting a star in the constellation Pegasus. First evidence
"For a decade we knew the sun was not the only star that was orbiting planets, but we finally have a true picture of a complete system," said Christian Marois, one of the authors of the research. ° ° °

The letters b and c show two of the three planets orbiting the star HR8799 observer by the Gemini telescope. ° ° °
"This is a milestone in the search and the characterization of planetary systems around stars, "he added.
The new solar system orbits a young star called HR 8799, located about 130 light years from Earth, which has 1.5 times the mass of our sun and is 5 times more luminous than this.
Three of the planets orbiting around it have about 10, 10 and 7 times the mass of Jupiter and are so young they still glowing from the heat released when they formed.
Scientists believe that this occurred sixty million years ago.
"In some ways, this planetary system appears to be a large-scale version of our solar system orbiting a star larger and brighter, "said Bruce Macintosh, another of the authors.
As in our solar system, these giant planets orbiting in the outer regions 24, 37 and 67 times the distance that separates Earth and the Sun
And the outermost planet orbits in a dusty debris disk that is similar to Kuiper Belt comets (in our solar system), 30 times the distance between Earth and the Sun
Many more
"We have not obtained a complete picture," said Dr. Marois.
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 The image shows light from the star Fomalhaut to detect blocked their planet.
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"The fact that we have found three planets around HR 8799 does not mean that no other planets orbiting at smaller separations. Perhaps there could be other gas giants or rocky planets," he said.
Moreover, the images captured by the Hubble telescope show a star called Fomalhaut in the constellation of Pisces Austrinus.
The star, as explained by Paul Kalas, who led the study, has a massive disk of dust orbiting around it.
The team believes that the planet has b baptized Fomalhaut is located about 18,000 million miles from its star as big as Jupiter and completes one orbit in about 870 years.
"I almost had a heart attack in late May when we confirm that Fomalhaut b orbits a star," Kalas said the doctor.
"Being able to see an end to this planet that has never before been seen, was a profound and extraordinary experience," he said. Direct detection
Until now, the search for extrasolar planets had been dependent on the detection of earthquakes that occur in its parent star. If their orbits are close to the history of telescopes, you can also see how it obscures the light from its star as they pass in front of her.
New research, however, managed to directly detect the light of these planets and this will allow astronomers to study in detail its composition and atmosphere.
experts also express the results of these studies will support the theories of how planets form from disks of dust and other bulk material surrounding the star. ° ° °

The graph shows the star and its planet Fomalhaut, the Fomalhaut b that Hubble observed.
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And that could help estimate how many planets like Earth could exist.
"Many times we saw an object near a star and we thought it was a planet," he told the BBC Mark McCaughrean, an astrophysicist at the University of Exeter, England.
"And although I was very skeptical in the past with these statements, the results of these two new studies seem to be very real."
"It is typical, you wait for years to see a planet and suddenly, they come four at a time," said the scientist. 
© 2008 BBC Science
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