NASA has confirmed the discovery of a record number of 715 new exoplanets, detected using the Kepler telescope. Four of these planets could sustain life.
The recent discovery doubles the number of exoplanets (planets outside our solar system) which now stands at 1,700. The 715 planets are located in solar-systems similar to ours, where several planets orbiting a star. Among them, four planets (Kepler-174d, Kepler-296f, Kepler-298d and Kepler-309c) is situated in the habitable zone, an ideal distance that allows for liquid water and maybe even forms of life.
The first exoplanets were detected 20 years ago and since then, checking them was very difficult. Researchers need to be sure that their information on the existence of planets are correct. Now, scientists from NASA have used a new method: they considered the stars who have around them more than one planet, explains Jack Lissauer (NASA’s Ames Research Center). Then they used a technique called verification by multiplicity, which relies in part on the logic of probability.
4 years ago, the Kepler telescope has observed thousands of potential planets, but they were only candidate worlds. In this recent analysis, astronomers have confirmed the discovery of 305 stars and 715 planets. Only four planets are 2.5 times bigger than Earth and they are located in the habitable zone. One of the interesting planets, called Kepler-296f, orbiting a star that is half the size of our Sun and only 5% of its brightness. The planet is twice as big as Earth, but scientists do not know whether it is a gas planet or one covered by a very deep ocean.
Launched in March 2009, Kepler Space Telescope is orbiting the Sun and has a mission to search for planets outside our solar system similar to Earth. It’s mission would have ended last year, but NASA decided to keep it running until 2016, with an annual cost rises to 20 million dollars. So far, Kepler has detected 3,600 potential planets, of which 961 were verified and confirmed (715 being announced by NASA, Wednesday.)