Endeavour Launch Scrubbed

NASA has scrubbed today’s launch for the Space Shuttle Endeavour.  Shuttle managers and engineers are discussing an issue with two heaters associated with shuttle Endeavour’s Auxiliary Power Unit (APU) 1.

The APU heater issue was noticed when the external tank was filled with cold hydrogen and a thermostat did not turn on the heater.

The launch will be scrubbed for at least 72 hours per NASA TV.