Shuttle commander Mark Polansky admitted yesterday what many already suspected – you can’t really Twitter from space. NASA astronaut Mark has been issuing regular tweets to update followers on preparations for the next shuttle mission to the International Space Station.

One was the first that most of us knew that today’s planned launch of space shuttle Endeavour had been postponed because of a hydrogen leak. Mark has promised regular reports from space too.

Last month, newspapers made much of the story that Mike Massimino was using Twitter as Astro_Mike to report on his crew’s work aboard sister shuttle Atlantis to repair the Hubble space telescope.

But responding to queries from other twitterers, Mark, pictured here, has revealed that, once in orbit, he will have to download his comments to NASA’s mission control where someone will post them for him.

In a series of genuinely direct tweets under his username Astro_127, Mark said:

“Twitter from orbit 101 Part 1: I do NOT have online internet access. 3 times a day, mission control sends up files that include email.”

“Twitter from orbit Part 2: While my email in arrives, my email out that have sat in a folder since I wrote them will b brought 2 the ground.”

“Twitter from Orbit Part 3: Once my emails 4 twitter arrive on the ground, someone will take them and post them on my twitter account.”

“Twitter from orbit Part 4: No one will edit my twitter posts, but they will NOT b live. I will put the date & time (CDT) that I wrote them.”

“Twitter from Orbit Part 5: Hope that clears up how twitter from orbit REALLY works.”

Endeavour’s launch has been tentatively postponed until Wednesday for a 16-day mission to continue building the space station. But the launch window will remain open until 20 June.

Photo: Shuttle commander Mark Polansky (NASA).

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