Sure, after decades of listening, there is still no message. But with more data to sift through, and new technologies with superior search capabilities, odds of hearing from E.T. are rapidly improving. If the probability in the decade 2011–2021 were x percent, it’s going to be 1,000 times x in the following decade, says Andrew Siemion, director of the Berkeley SETI Research Center. (SETI stands for Search for Extra-Terrestrial Intelligence.)
The reason for E.T. optimism stems largely from several new projects in the works, enhanced with advanced methods for discerning an actual message hidden in the static of cosmic cacophony.
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SETI researchers have long agreed that if a signal is detected, no response would be made until a global consensus had been reached on who will speak for Earth and what they would say. But that agreement is totally unenforceable, [astronomer Jill] Tarter pointed out, and nobody has any idea about how to reach a global consensus on anything. (Perhaps the proper reply would just be “HELP!”)