NASA has called off the launch for the space shuttle Endeavour due to a heating problem. The launch was set to be the last one for the space shuttle before it went into retirement. An estimated 700,000 visitors were due to watch the launch at Kennedy Space Center in Florida Friday at 3:47 p.m. EST.
NASA said that during today’s countdown, a failure in one of the two heater circuits associated with the above mentioned APU 1 was detected. The heaters are rather important–they prevent the on-board hydrazine from freezing. Engineers think the problem might have something to do with a switchbox located in the rear end of the Endeavour. It also might be an electrical short in the wires associated with the switchbox. There will be a minimum 72-hour turnaround time to fix this problem. (If you were wondering, hyrdazine is used by shuttles as a propellent to move thrusters.)
Cmdr. Mark Kelly will be leading the Endeavour’s launch. Kelly is married to Rep. Gabrielle Giffords who was injured in January’s mass shooting in Tucson, Arizona. President Barack Obama along with his wife and daughters were also planning to attend the launch, which would be the first time in NASA history that the current president and his family did so.
A press conference is scheduled for 4 p.m. today to discuss today’s scrub and the resulting plan.