U.S. Embassy in Yemen will be closed to public until further notice due to security concerns, U.S. State Department says.
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Gallery: Original film of debris hitting wing
Ex-NASA engineer: 'No safety program' at NASA
Officials: 'No evidence of terrorism'
Animation: Space Shuttle Columbia tragedy
Audio: 911 calls
Audio: Final contact with Columbia
Timeline: Columbia's final moments
Video: Radar images of breakup
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TIME: The shuttle's last moments
Space Shuttle Columbia
Gallery: Flight STS-107 on Columbia
Diagram: Shuttle Columbia
Video: Columbia lifts off
Interactive: Shuttle prep course
Interactive: Flight stages
Timeline: Shuttle milestones
Panoramas: Space vault
Interactive: Shuttle Discovery