A international team of astronomers revealed that it has discovered 28 new planets outside the solar system, making it the largest number of planets discovered since the first exoplanet was found nearly 12 years ago.
Among the 28 planets discovered, at least four belong to multiple-planet systems, Jason Wright of the University of California and a member of the team, said, adding that this evidence would mean that at least 30 percent of stars in the universe have multiple-planetary system.
"Taken together, in the last year our teams have increased the number of known planets by 12 percent and shown that at least 30 percent of stars known to host planets have more than one object orbiting", Wright said at the annual meeting of American Astronomical Society in Honolulu.
The recent haul takes the total number of planets discovered outside our solar system to 236. Geoffrey Marcy, a professor of astronomy at the University of California Berkeley, believes that the rising number of planet discoveries outside the solar system indicates that Earth is not a unique planet.
"We are beginning to see that our home is not a rarity in the universe. We are easily able to detect giant planets like Jupiter and Saturn around other stars. Most orbit far from the star like our own Jupiter and Saturn orbit from the sun", he said.
Marcy went on to add that he believed at least 10 percent of the planets in the Milky Way galaxy are habitable. "Our Milky Way galaxy has 200 billion stars. I would estimate that 10 percent of them, perhaps, have planets that are habitable. There are hundreds of billions of galaxies, all of which are more or less like our Milky Way galaxy, which is tens of billions of planets like our own", he added.
