Technicians will begin loading hydrazine fuel into space shuttle Discovery’s three auxiliary power units today. The APUs are turned on five minutes before liftoff and provide power to the several systems during the climb into orbit, including the hydraulics that steer the main engines. Discovery, which stands at Launch Pad 39A at NASA’s Kennedy Space Center in Florida, is being readied for liftoff on the STS-133 mission, targeted for Nov. 1 at 4:40 p.m.EDT. At NASA’s Johnson Space Center in Houston, Discovery’s six-person crew will continue their bench review.