Photos: Endeavour soars on 2nd-to-last space shuttle trip

Posted: Updated:
The space shuttle Endeavour lifts off from Kennedy Space Center in Cape Canaveral, Fla., Monday, May 16, 2011. The space shuttle Endeavour began a 14-day mission to the international space station. (AP Photo/John Raoux) By John Raoux The space shuttle Endeavour lifts off from Kennedy Space Center in Cape Canaveral, Fla., Monday, May 16, 2011. The space shuttle Endeavour began a 14-day mission to the international space station. (AP Photo/John Raoux) By John Raoux
Space shuttle Endeavour clears the launch pad at Cape Canaveral, Fla., on Monday, May 16, 2011.  (AP Photo/Chris O'Meara) By Chris O'Meara Space shuttle Endeavour clears the launch pad at Cape Canaveral, Fla., on Monday, May 16, 2011. (AP Photo/Chris O'Meara) By Chris O'Meara

CAPE CANAVERAL, Fla. (AP) -- Space shuttle Endeavour is finally on its way.

Endeavour blasted off on the next-to-last shuttle flight Monday morning under the command of Mark Kelly, the husband of Rep. Gabrielle Giffords. The wounded congresswoman watched the launch in private from Kennedy Space Center.

As many as 45,000 guests jammed NASA's launch site. 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.

Only one other shuttle trip remains.