Nasa Warming Space Shuttle

Trying to prevent a repeat of the Challenger disaster, NASA used heaters to warm space shuttle Endeavour for liftoff today in the early morning cold.

NASA expected it to be 44 degrees for Endeavour’s 4:18 a.m. launch on a satellite-retrieval mission. That would probably be warm enough under the rules established after the 1986 catastrophe.

The temperature was 36 degrees, the coldest ever for a shuttle launch, when Challenger exploded 10 years ago this month, killing all seven crew members. Investigators found that the cold had stiffened the O-rings in the shuttle’s booster rockets, allowing hot gas to seep out.

After the accident, NASA adopted an elaborate formula involving low temperature, wind and humidity in determining whether it is safe to launch. Heaters also were added to protect the joints and O-ring seals in the boosters and other components.