Based on his new biography, “The Believer: Alien Encounters, Hard Science, and the Passion of John Mack,” veteran New York Times reporter Ralph Blumenthal tells the gripping story of how a Pulitzer prize-winning author and pillar of the medical establishment at America’s proudest academic citadel risked everything to defy widespread ridicule and chase a colossal cosmic mystery. Mack’s hero’s journey, imperfect as it had to be, exemplifies the best of the human species.