Radio Stars

摘要

In 1982, Carl Sagan sent a letter, cosigned by 72 scientists, to Science calling for a "systematic international research effort" to search for communications from extraterrestrial civilizations. Months later, Congress dedicated $1.5 million to the NASA program SETI (the Search for Extraterrestrial Intelligence) and, within two years, scientists at NASA's Gold-stone Deep Space Communications Complex in California were installing equipment to detect transmissions from intelligent life. "I think that in the next 10 or 20 years," said SETI astronomer Michael Papagiannis, "we will either have detected some sort of signal from SETI, or we will begin to accept the fact that we are alone in our galaxy."