Ted Turner made sure CNN would never go quietly. The late media mogul — who died Wednesday at 87 — secretly commissioned a chilling “doomsday video” decades ago that was meant to air only when the world came to an end, according to resurfaced footage and archived reports. The eerie clip, long treated as a legend inside CNN, featured military bands from the US Army, Navy, Air Force and Marines solemnly performing the Christian hymn “Nearer, My God, to Thee” outside the network’s original Atlanta