Forty years ago this week, the Space Shuttle Challenger launched from Kennedy Space Center at Cape Canaveral, Florida. Then, 73 seconds after ignition, it exploded in mid-air, killing all seven astronauts on board, including teacher Christa McAuliffe. David Klaus, professor emeritus of aerospace engineering at the University of Colorado Boulder, worked for NASA at the time, and explained how the disaster changed the federal agency's approach to decision-making and risk analysis.
