Scientists using NASA's powerful Kepler telescope have found a planet beyond the solar system that is a close match to Earth.The planet, which is about 60 percent bigger than Earth, is located about 1,400 light years away in the constellation Cygnus, the scientists told a news conference on Thursday.While similarly sized planets have been found before, the latest one, known as Kepler-452b, is circling a star that is very similar but older than the sun at a distance about the same as Earth's orbit."It's great progress in finding a planet like Earth that is similar in size and temperature around a sun-like star," Jeff Coughlin, Kepler research scientist at the SETI Institute in Mountain View, California, told reporters on a conference call.Based on its size, scientists believe Kepler-452b is rocky and Earth-like and positioned at the right distance for liquid surface water, which is believed to be necessary for life.The research will be published in an upcoming issue of The Astronomical Journal.