Kepler scientists have yet to announce a true Earth analog, but already have added 962 confirmations and 3,845 candidates to the list of 1,792 planets discovered beyond the solar system.
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Hundreds of the Kepler planets turned out to be in multi-planet systems, a discovery that caught the eye of Werthimer and colleagues.
A graduate student created a computer program to predict when extrasolar planets would line up with Earth and the team wrote proposals for observing time on radio telescopes.
"This is the first time in history we have had such specific and accurate information about other planetary systems and had the opportunity to consider how we could use it to improve the efficacy of our searches," SETI scientist Andrew Siemion, with University of California Berkeley, the Netherlands Institute for Radio Astronomy and Radboud University in The Netherlands, wrote in an email to Discovery News.
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The Green Bank Telescope in West Virginia was the first to sign on, awarding the team a total of 36 hours to attempt to eavesdrop on ET. Scientists collected data during 75 conjunctions, with no alien transmissions detected. Additional proposals are pending.