A tool designed to determine the concluding portion of the nighttime period, typically used in contexts where precise timing or scheduling relative to the end of the night is required. This calculation involves dividing the total duration of nighttime (from sunset to sunrise) into three equal segments, with the segment representing the last third being the focal point. For instance, if nighttime lasts nine hours, the concluding third would be the final three hours before sunrise.
The significance of accurately establishing this nocturnal segment stems from various practical applications. Historically, it has been critical in fields such as astronomy, religious observances, and military operations, where activities are planned based on natural light cycles. Precise knowledge of this period can optimize resource allocation, enhance situational awareness, and facilitate synchronization of events that depend on the diminishing darkness.