Rep. Gabrielle Giffords (D-Ariz.) boarded a plane Wednesday at Ellington Airport in Houston headed to Cape Canaveral, Fla., where she will watch the final launch of the Space Shuttle Endeavour.

Giffords was accompanied on the NASA-operated flight by a nurse from TIRR Memorial Hermann Hospital. The congresswoman has been undergoing rehabilitation there after suffering a gunshot wound to the head during a shooting rampage in January.

Endeavour will be commanded by Giffords's husband, astronaut Mark Kelly; it is scheduled to launch at 2:47 p.m. Friday.

President Obama and his family are also expected to attend the launch. A congressional delegation will be on hand as well.

Doctors have praised Giffords's progress. The Arizona Republic recently quoted Kelly as saying he continues to see his wife's condition improve.

"I can't say I notice improvement every day, but I can every few days," Kelly said.

Still, Giffords's doctors warn that "outpatient rehab is far off."