Endeavour Blasts Off Gabrielle Giffords in attendance By Newser Editors and Wire Services Posted May 16, 2011 8:22 AM CDT 0 comments Comments The space shuttle Endeavour lifts off from Launch Pad 39A at the Kennedy Space Center on May 16, 2011 in Cape Canaveral, Florida. (Getty Images) (Newser) – Space shuttle Endeavour is finally on its way. Endeavour blasted off on the next-to-last shuttle flight this morning under the command of Mark Kelly, the husband of Rep. Gabrielle Giffords. The wounded congresswoman watched the launch in private from the Kennedy Space Center. As many as 45,000 guests jammed NASA's launch site, and the crowd outside the gates was estimated to be in the tens of thousands, if not more. It was the second launch attempt. Late last month, an electrical problem halted the countdown. Endeavour and its six astronauts will arrive at the International Space Station on Wednesday. They are delivering a $2 billion particle physics experiment. The mission will last 16 days.