Despite weather concerns, the final U.S. space shuttle flight successfully launched Friday as Atlantis lifted off from Cape Canaveral, Fla., NASA said. Initially given just a 30 percent chance of being able to launch because of area thunderstorms, weather cleared long enough for a launch at 11:29 a.m., just 3 minutes past the scheduled liftoff. Atlantis, the last active shuttle orbiter, escaped damage from two nearby lightning strikes during a thunderstorm Thursday afternoon, NASA said. One lightning bolt struck the water tower 515 feet from the launch pad, the space agency said. NASA estimated 500,000 to 750,000 spectators viewed the last-ever mission launch in the agency's 30-year shuttle program. The 12-day mission will be run by a four-person crew, the smallest of any shuttle mission since the sixth shuttle flight that began April 4, 1983. The Atlantis commander is Christopher Ferguson, a retired U.S. Navy captain who piloted Atlantis on his first mission in September 2006, and Endeavour in November 2008. The other crew members are pilot Douglas Hurley, a U.S. Marine Corps colonel who piloted Endeavour in July 2009; mission specialist Sandra Magnus, an engineer who was part of the Discovery crew in March 2009 after spending 134 days in orbit; and mission specialist Rex Walheim, a retired U.S. Air Force colonel who flew on Atlantis in April 2002 and again in February 2008. The mission will bring cargo to the International Space Station in the large, pressurized multipurpose logistics module Raffaello, named by its maker, the Italian Space Agency, after the Renaissance painter and architect Raffaello Sanzio -- better known as Raphael -- who with Michelangelo and Leonardo da Vinci formed the traditional trinity of great masters of that time. All Atlantis crew members have been custom-fitted for a Russian Sokol spacesuit and molded Soyuz seat liner should they have to return to Earth in a Soyuz capsule in case Atlantis can't make the re-entry and land. Atlantis, which has circled Earth more than 4,600 times, traveling more than 120 million miles in space, is expected to add 5 million more miles to its record during its final mission.