The current issue of Nature contains several pieces about astrobiology and SETI (Search for Extraterrestrial Intelligence), in celebration of the 50th anniversary of a paper by Giuseppe Cocconi and Philip Morrison, which made the search for technologically advanced ETs by listening out to possible radio communications respectable. Frank Drake (who later introduced the Drake equation to estimate the probabilities involved) had started such research even earlier, but it had been kept secret for fear of ridicule and funding withdrawal.
Opinion piece by Fred Kaplan
Original paper by Cocconi and Morrison, Searching for Interstellar Communications, Nature 184, 844 - 846 (1959)
Editorial: Seti at 50
News story: Ear to the Universe starts listening