Decreasing count indicating the time (typically in seconds) remaining before an event is scheduled to occur
Also known as T minus
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6 identifiers linking countdown across the web's reference databases
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A countdown is a sequence of backward counting to indicate the time remaining before an event is scheduled to occur. NASA commonly employs the terms "L-minus" and "T-minus" during the preparation for and anticipation of a rocket launch, and even "E-minus" for events that involve spacecraft that are already in space, where the "T" could stand for "Test" or "Time", and the "E" stands for "Encounter", as with a comet or some other space object, like a spacecraft.