For the last shuttle launch of Atlantis, 150 lucky individuals were invited to attend the official NASA Tweetup to experience the lift-off first-hand, with exclusive behind the scenes access to astronauts, facilities, lectures and more. Join Erik Sowa, NASA Tweetup attendee and director of engineering at ExactTarget's Social Media Lab, and Stephanie Schierholz, NASA's head of social media, at 5:00pm on Sunday, March 11 for NASA’s Mission Possible: Tweeting thru Space. Erik and Stephanie will take you into process behind this groundbreaking event as part of the SXSW Interactive Social Networks Theme in the Capital Ballroom at the Omni Downtown.

Contributed by Christine Auten, photo of STS-135 Tweetup Participants in front of the Space Shuttle Atlantis at the Kennedy Space Center Photo by Paul E. Alers/NASA