The world's most eminent scientist of space explains why he believes in extraterrestrial life

Abraham (Avi) Loeb is the Frank B. Baird, Jr., Professor of Science at Harvard University, longest-serving chair of Harvard's Department of Astronomy, founding director of Harvard's Black Hole Initiative, and current director of the Institute for Theory and Computation (ITC) within the Center for Astrophysics | Harvard & Smithsonian.
He also heads the Galileo Project, chairs the Advisory Committee for the Breakthrough Starshot Initiative, and is former chair of the Board on Physics and Astronomy of the National Academies.
Author of eight books and over a thousand scientific papers, Loeb is an elected fellow of the American Academy of Arts & Sciences, the American Physical Society, and the International Academy of Astronautics. In 2012, Time selected Loeb as one of the twenty-five most influential people in space. He lives near Boston, Massachusetts.