Space duties cramp astronaut’s ‘tweets’

GREENBELT, Md. —- On Twitter, messages of 140 characters may seem confining. Mike Massimino is finding a different type of space even more limiting —- outer space.

The astronaut is sending messages to the social networking site (www.twitter.com/Astro_mike) from 350 miles above Earth on the shuttle Atlantis. What’s cramping his “tweets” is time, not the character limit.

On Earth, Massimino tweeted about working out and watching a movie. In space, he just doesn’t have the time to tweet the routine. He averaged about four tweets a day before launch. Now, it’s down to one a day.

Astro_Mike (Massimino’s Twitter name) is the first person to tweet from space: “From orbit: Launch was awesome!! … the adventure of a lifetime has begun!”

The tweets may get more scarce. Massimino, 46, an adjunct professor in industrial and systems engineering at Georgia Tech, will be spacewalking today.