The launch of Endeavour was scrubbed at least until Sunday because of technical problems, NASA officials said.
Mike Leinbach, launch director, officially scrubbed the launch even as the astronauts were traveling in the van to their shuttle.
President Obama and U.S. Rep. Gabrielle Giffords whose husband Mark Kelly is commander of this mission were to be on hand for the launch.
Weather had already been a concern, with blustery, stormy weather hanging over the cape. Forecasts expect conditions to improve throughout the day.
As early as 9 a.m. today, parking was at a premium in downtown Titusville as business owners turned their parking lot into money-makers.
The price ranged from $5 to $25. Parking along a narrow strip of grass near U.S. Highway 1 and State Road 50 – with an unobstructed view of the launch site – was going for $20.
Under a small tent, "official NASA shuttle shirts" were for sale.
Endeavour was set to blast off for a 14-day mission to bring the long-delayed Alpha Magnetic Spectrometer to the International Space Station, along with critical supplies, spare parts and equipment. Then, like Discovery, it will slip off into retirement.
Endeavour is the newest of the five shuttles that have flown in the 30 years since Columbia made its maiden flight. Endeavour debuted in 1992; this will be its 25th mission.
Though its record includes the first servicing mission to the Hubble Space Telescope and the first major construction of the space station, it is the kid sister of the fleet, forced into an early grounding — along with the rest of the shuttles — after Columbia's disastrous end in 2003.
But Endeavour might get the greatest sendoff. President BarackObama is making a rare presidential visit to watch a launch — the most recent was by Bill Clinton in 1998.
NASA released a list of 118 VIPs expected for the launch, U.S. Sens. Bill Nelson and Marco Rubio, and numerous federal officials, foreign dignitaries and business leaders. The list also includes Florida Gov. Rick Scott, but his office had said on Friday confirmed what it had said earlier this week – that he would not be attending..
NASA test director Jeff Spaulding said he expects "an incredible crowd" — estimated at 45,000 people at Kennedy Space Center and 700,000 in Brevard County.