Just last week, astronomers announced they had discovered three super-Earths, each of them between four and 30 times bigger than our planet. And dozens of other worlds suspected of having masses in that same range were found around other stars.
Being able to find three Earth-mass planets around a single star really makes the point that not only may many stars have one Earth, but they may very well have a couple of Earths,” said Alan Boss, a planet formation theorist at the Carnegie Institution of Washington in Washington, D.C.
Since the early 1990s, when the first planets outside of our solar system were detected orbiting the pulsar PSR 1257, astronomers have identified nearly 300 such worlds. However, most of them are gas giants called hot Jupiters that orbit close to their stars because, simply, they are easier to find.
“So far we’ve found Jupiters and Saturns, and now our technology is becoming good enough to detect planets smaller, more like the size of Uranus and Neptune, and even smaller,” said one of the top planet hunters on this world, Geoff Marcy of the University of California, Berkeley.
Marcy, Boss and other scientists are optimistic that within the next five or so years headlines will be splashed with news of a near twin of Earth in another star system.
“What is amazing to me is that for thousands of years humans have gazed at the stars, wondering if there might be another Earth out there somewhere,” Boss told SPACE.com. “Now we know enough to say that Earth-like planets are indeed orbiting many of those stars, unseen perhaps, but there nevertheless.”
Original Story: Astronomers on Verge of Finding Earth’s Twin .