”Life in the Universe and the Fermi Paradox”. For forty-five years, even as the public grew accustomed to talk of 'alien,' life, astronomers and others have puzzled over 'The Great Silence' out there, a lack of any signs or traces of previous civilizations in the Milky Way Galaxy, a problem often called the Fermi Paradox. Over a hundred hypotheses have been offered, from credible to highly implausible. Discovery of many thousands of extrasolar planets has altered several factors in the Drake Equation. In a time of rapid discovery, it seems inappropriate to meddle in the experiment by deliberately shouting 'messages' into the cosmos.
