More than sixty years ago, the Search for Extraterrestrial Intelligence (SETI) officially began with Project Ozma at the Greenbank Observatory in West Bank, Virginia. Led by famed astronomer Frank Drake (who coined the Drake Equation), this survey used the observatory's 25-meter (82-foot) dish to monitor Epsilon Eridani and Tau Ceti - two nearby Sun-like stars - between April and July of 1960. Since then, multiple surveys have been conducted at different wavelengths to search for indications of technological activity (aka. "technosignatures") around other stars.
While no conclusive evidence has been found that indicates the presence of an advanced civilization, there have been many cases where scientists could not rule out the possibility. In a recent paper, veteran NASA scientist Richard H. Stanton describes the results of his multi-year survey of more than 1300 Sun-like stars for optical SETI signals. As he indicates, this survey revealed two fast identical pulses from a Sun-like star about 100 light-years from Earth, that match similar pulses from a different star observed four years ago.
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