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Engineer Who Warned Of Challenger Dangers Dies

The rocket scientist who argued vigorously against the fatal launch of the Space Shuttle Challenger has died. Roger Boisjoly led a group of five Morton Thiokol engineers who tried to stop the launch in a series of conference calls with NASA the night before the tragedy. Boisjoly presented data showing cold launch-time temperatures could cause the joints on the shuttle's booster rockets to fail catastrophically. He was also one of two whistleblowers who anonymously revealed the launch decision debate to NPR a few weeks after the launch.