CAPE CANAVERAL, Fla. (AP) - Countless clues left investigators with few answers as they probed what caused the breakup of space shuttle Columbia after the deadly disaster spewed debris across hundreds of miles. In addition to examining the wreckage, NASA was analyzing transmissions from the crew, records from the shuttle's sensors and data from military, government and commercial satellites. "We will be poring over that data 24 hours a day for the foreseeable future," NASA shuttle project manager Ron Dittemore told a Houston news conference Saturday, hours after the tragedy. The space agency put a hold on all shuttle launches...