The space shuttle Endeavour sits on launch pad 39-A at the Kennedy Space Center. (Mark Wilson/Getty Images)

Astronauts of space shuttle Endeavour. (John Raoux/AP)

The mission is the second to last flight for NASA’s space shuttle program, and it carries extra emotional weight. The commander of the flight is astronaut Mark Kelly, husband to Rep. Gabrielle Giffords. Giffords arrived in Cape Canaveral, Fla., on Sunday to cheer on her husband, just four months after being shot in the head in the Jan. 8 attack that left six dead and 12 injured.

Giffords made the trip to Florida for the initial launch in April and a video captured her walking onto the plane — the first and only time she’s been seen since the shooting in Tucson.

Watch video of the launch here:

Gabrielle & Mark said goodbye during visit before launch. Beach House made for picturesque setting. than a minute ago via Twitter for BlackBerry® Favorite Retweet ReplyGabrielle Giffords

Meanwhile, Endeavour astronauts send out messages before the launch:

Dear God, please bless our crew. Help us in our mission and to return safely home. Please help me not to mess anything up.less than a minute ago via web Favorite Retweet ReplyCol. Mike Fincke

Good Morning!! I am really excited and charged up for this mission! Slept great - enjoyed amazing coffee and breakfast with my crew at 0100.less than a minute ago via Twitter for iPhone Favorite Retweet ReplyGregory H. Johnson

Launch day. We should be pulling off Earth in a couple hours. Liftoff at 8:56a ET. Watch: than a minute ago via Twitter for iPhone Favorite Retweet ReplyMark Kelly

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