On the cold morning of January 28, 1986, 40 years ago today, the Challenger shuttle crew of seven astronauts died tragically in the explosion of their spacecraft during the launch of STS-51L from the Kennedy Space Center. The explosion occurred 73 seconds into the flight as a result of a leak in one of two solid rocket boosters that ignited the main liquid fuel tank. The crew members of the Challenger represented a cross-section of America in terms of race, gender, geography, background, and religion. It was a shockingly sad day for all of us. The explosion became one of the most significant events of the 1980s, as millions around the world saw the tragic event unfold on live television.