NASA postpones 'Atlantis' shuttle launch again

NASA postponed Friday's launch of the space shuttle Atlantis, this time because of a problem that has bedeviled the space agency before: a faulty fuel tank sensor. The launch was rescheduled for 11:15 a.m. EDT (1515 GMT) on Saturday, when NASA will try a fourth time to get Atlantis off the ground. Previous attempts over the past 12 days were dashed by a lightning bolt that struck the launch pad, Tropical Storm Ernesto and a fuel cell coolant pump that gave an erratic reading. This time, a sensor in the hydrogen fuel tank gave an abnormal reading during a test as the shuttle was being fueled early Friday.