Atlantis' journey to the International Space Station will be NASA's 135th and final mission in the space shuttle program, which began 30 years ago. Tune in to CNN's live coverage of the launch Friday, starting at 10 a.m. ET on CNN, CNN.com/Live and the CNN mobile apps. Then check out "CNN Presents: Beyond Atlantis" Friday at 10 p.m. ET.
Kennedy Space Center (CNN) -- Despite a good chance of thunderstorms, Atlantis is fueled up and ready to blast off Friday morning in the final mission of America's 30-year space shuttle program.
The very last launch for a space shuttle is set for 11:26 a.m. ET.
The crew donned their orange suits and were expected to depart for launch pad 39A at 7:36 a.m. The crew will begin boarding the shuttle shortly afterward.
Thousands of people, among them those who came to Kennedy Space Center three decades ago for the very first launch, gathered to watch. Almost a million are expected to be on hand to witness the historic event.
But it's summer in Florida and the weather remains a wild card.
Violent storms Thursday prompted NASA teams to carry out checks on the Atlantis. NASA said the shuttle escaped damage from two lightning strikes.
One bolt emanating from a severe thunderstorm struck a water tower 515 feet from the pad; the second struck the beach nearby, the space agency said in a statement.
Showers were on the radar again for Friday, but breaks in the clouds heightened hopes for a Friday launch.
The final mission will take four astronauts, all of them shuttle veterans, into space for 12 days where they will deliver supplies to the international space station.
After the Apollo space program put a man on the moon in 1969, President Richard Nixon commissioned the space shuttle program in 1972.
The first shuttle, Columbia, blasted off in April 1981. Since then, the fleet of space shuttles have fixed satellites, performed scientific studies, and ferried materials and people to international space station Alpha, a football field-sized construction project in orbit.
In 134 missions, the five space shuttles have ferried 355 astronauts half a billion miles in space, turning heroic feats into the routine.
"I don't think we'll see another vehicle like it, for decades perhaps," Atlantis commander Chris Ferguson recently told CNN. "I mean, just the technology involved in flying back from space. It's an amazing vehicle, and its legacy will live on."