This NASA artist concept depicts multiple-transiting planet systems, which are stars with more than one planet. The planets eclipse or transit their host star from the vantage point of the observer. This angle is called edge-on.
NASA's Kepler space telescope has discovered more than 700 new exoplanets, nearly doubling the current number of confirmed alien worlds.
The 715 newfound planets, which scientists announced today (Feb. 26), boost the total alien-world tally to between 1,500 and 1,800, depending on which of the five main extrasolar planet discovery catalogs is used. The Kepler mission is responsible for more than half of these finds, hauling in 961 exoplanets to date, with thousands more candidates awaiting confirmation by follow-up investigations.
"This is the largest windfall of planets — not exoplanet candidates, mind you, but actually validated exoplanets — that's ever been announced at one time," Douglas Hudgins, exoplanet exploration program scientist at NASA's Astrophysics Division in Washington, told reporters today. [Kepler's Exoplanet Bonanza Explained (Infographic)]
About 94 percent of the new alien worlds are smaller than Neptune, researchers said, further bolstering earlier Kepler observations that suggested the Milky Way galaxy abounds with rocky planets like Earth.
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