CAPE CANAVERAL, Fla. - Space Shuttle 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 Kennedy Space Center.

It was the second launch attempt because late last month, an electrical problem halted the countdown.

Endeavour and its six astronauts will arrive at the International Space Station Wednesday.

The crew is bringing a science experiment from Shelton High School with them.

The students are testing the effect zero gravity has upon developing cell walls.