The Shuttle Endeavour is set to blast off one last time Monday morning./ The space shuttle will be carrying a $2 billion particle physics detector called the Alpha Magnetic Spectrometer, which will search for dark matter. It is an emotional day for commander Mark Kelly, who is heading the mission. His wife, Arizona Rep. Gabrielle Giffords, who was shot in the head is at the launch site. Kelly is carrying a wedding ring into space. Science reporter for The New York Times, Henry Fountain is at the launch.