Captain Williams is a NASA astronaut who recently completed the first triathlon in space.
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Can't get enough photos from the Curiosity rover? Dying to know what's happening on the International Space Station? Interested in how NASA astronauts train? These Twitter accounts are for you.
We left out the obvious accounts like @NASA, but we did include some other official agency accounts you may not yet follow. A handful of astronauts also made this list, but if you want a full feed of all the NASA astronauts, follow @NASA_Astronauts, who wins our honorable mention today.
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This list is filled with tweeps who put a human voice on the vast universe beyond our planet Earth. But perhaps most importantly, they all promote the often underappreciated world of science. And some of them add a little humor to the mix as well.
Did we leave any of your favorite space Twitter accounts off this list? Share them with us in the comments below.
This story originally published on Mashable here.