But feelings of excitement, the night before Christa’s launch aboard the shuttle Challenger, were not universal. The weather was unseasonably cold. Unknown to almost everyone, extremely cold weather could jeopardize the entire mission.

Members of the launch team hotly debated the merits of delay. Roger Boisjoly, a Morton Thiokol engineer, warned of a catastrophe if the weather did not improve. He, and others, were concerned about a design flaw in the solid rocket booster.

But those favoring a later launch lost the argument. As a result, Challenger and her crew (including America’s first teacher in space) were blown out of the sky seventy-three seconds after their January 28, 1986 launch.

In this story behind the disaster, meet the astronauts and virtually visit Cape Canaveral to see its icy conditions before launch. Examine pictures of smoke coming from the right solid rocket booster while Challenger was still on the ground. Coordinate evidence from the Rogers Commission, with NASA pictures and videos, to see why Challenger exploded. Read the official transcript of the crew’s last recorded words.

Meet Dr. Richard Feynman and observe how he helped uncover the design flaw in the rocket booster’s o-rings. See Roger Boisjoly’s memo where he warned about the o-rings and discussed their partial failures in other shuttle missions. And ... discover the medical examiner’s report which Dr. Kerwin wrote after analyzing the astronauts’ remains.