Did a NASA astronaut really “tweet” from space? That’s the question bouncing around Twitter about “Astro_Mike,” or Mike Massimino, an astronaut on space shuttle Atlantis, set to land today at Kennedy Space Center. On May 12, Massimino wrote, “From orbit: Launch was awesome!! I am feeling great, working hard, & enjoying the magnificent views, the adventure of a lifetime has begun!” Ever since, NASA, newspapers, TV shows and blogs have been crediting him as the first person to post on the microblogging service, or “tweet,” while in orbit. In reality, Massimino writes his updates in space and then e-mails them to Houston, where a NASA employee posts them to his Twitter profile. That often takes hours because e-mails are transmitted from the shuttle only a few times a day. Read…