Above, the Astrovan carrying the STS-121 crew passes the Launch Control Center on its way to Pad 39B. Below, astronaut Mike Bloomfield circles KSC in the Shuttle Training Aircraft as he performs weather reconnaissance:

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One of the many thunderstorms and associated anvil clouds that led to the scrub of the second launch attempt::
A KSC Swat Team member follows the Astrovan on the way to the pad: