You may remember, or maybe not, that Endeavour was to launch from Florida last Friday.  Yes, that was the same day as the Royal Wedding so it took a back seat.  However, the launch was delayed for mechanical reasons. Mark Kelly the Commander of the Endeavour mission is the husband of Gabby Gifford's, the Arizona Congresswoman who was shot in January.  She has been in Houston at a rehabilitation facility and was

well enough to make the flight to Florida last week to watch the launch, however, she is now back in Houston and will again fly to Florida when a launch date is set.  NASA is shooting for next Monday or Tuesday but that's just a goal, it's not a set date as of yet.   This is one of the last shuttle missions that will be flown before the Space Shuttle program is retired for good.  The delay was caused by a thermostat problem that must be working for launch.

Endeavour's launch-pad team is currently in the midst of repairing a faulty heater in one of the orbiter's three auxiliary power units. The units provide hydraulic pressure for the aerodynamic control system, and NASA's rules say all three must be working for launch.