It was unusually cold on the morning of the Space shuttle's launch. The engineers argued that the "Challenger" should not take off because the temperature was and the O-rings could not seal right if the temperature was under . The NASA commanders did not agree and said that the backup O-ring would work. They were later proved wrong. The temperature was so low that icicles were hanging from some parts of the launch pad. However, the NASA commanders convinced the engineers' managers to overrule them and approve the launch.