Initial thrust from NASA Space Shuttle launch (iStockphoto) 73 seconds. That’s how much time elapsed before the Space Shuttle Challenger exploded after liftoff on January 28, 1986. The reality, however, is that this was a tragedy decades in the making. The lessons, and the risks, are just as applicable now as they were 40 years ago. The Shift During the Apollo missions in the 1960s and early ’70s, NASA’s posture toward risk was simple: we don’t launch until we can prove it’s