Twitter users Risa Wechster from Stanford University, left, and Daniel Holz from Los Alamos, both twitter for @cosmicvariance during a two-day NASA Tweetup event held at NASA's Kennedy Space Center in Cape Canaveral, Fla, Sunday, Nov. 15, 2009. NASA Twitter followers in attendance will have the opportunity to take a tour of NASA's Kennedy Space Center, view the STS-129 space shuttle launch and speak with shuttle technicians, engineers, astronauts and managers. Photo Credit: (NASA/Carla Cioffi)