In addition to being a national tragedy, the shooting of Representative Gabrielle Giffords and several other individuals in Arizona also threatens to complicate NASA's plans for what could be the final flight of the 30-year-old space shuttle program.

Representative Gabrielle Giffords, who was shot through the head on Saturday by deranged gunman Jared Loughner, is the wife of astronaut Mark Kelly. Kelly is scheduled to be the flight commander aboard the shuttle Endeavour when it makes the last, currently scheduled shuttle flight this spring.

NASA has said it may operate one additional flight before ending the program, but that remains uncertain.

With Giffords lying in an Arizona hospital with a critical head wound, and facing months, if not years, of rehabilitation if she pulls through—an outcome doctors see as increasingly likely—there's a chance Kelly will step down from the mission to remain at his wife's side.

NASA officials said that, for now, Kelly hasn't been ruled in, or out, for STS-134--the official name of Endeavour's final mission.

"It's just too early to speculate," a spokesperson for the space agency told the Web site Space.com. "Right now the focus is on Mark and Scott (Kelly's twin brother, currently aboard the International Space Station), and of course, the victims and their families. For the time being, everything is day by day."

Regardless of the outcome, Kelly's background will doubtless help him cope with the stress he's facing as he monitor's his wife's condition. The former Navy pilot is a veteran of 39 combat missions flown during Operation Desert Storm. The West Orange, New Jersey native also graduated with the highest honors from the U.S. Merchant Marine Academy.

Kelly and Giffords married in2007.

Endeavour is scheduled to lift off on STS-134 on April 1, to deliver communications equipment and spare parts to the ISS. The mission was pushed back due to problems with STS-133, which will see Discovery make its final flight. NASA is hoping to launch Discovery in late February, after cancelling previous launch attempts due to cracks found in the orbiter's external fuel tank.

NASA intends to end the shuttle program in 2011. Last year, President Obama asked the space agency to turn missions to the ISS over to private contractors, including Space Exploration Technologies Inc., and focus instead on long range plans like eventually launching a manned mission to Mars.