Updated (11:29 EST): The Atlantis has now blasted off from the Kennedy Space Center launch pad, watch below.
The Atlantis is scheduled to blast off from the Kennedy Space Center in Florida at 11:26 EST. NASA had previously estimated that there's a 70 percent chance that weather may delay the launch, but the official Twitter account of the Kennedy Center now relays: "Weather is now 'green'. Let's go Atlantis!" NASA's launch coverage adds:
Weather across Kennedy Space Center is observed 'go,' and hopefully conditions will remain that way for the next 40 minutes or so -- long enough for space shuttle Atlantis and a crew of four astronauts to launch on the STS-135 mission.
The live-feed is below, where you'll be able to watch the final launch of the space shuttle era: