Helek in Wikipedia
The helek (Hebrew חלק, meaning "portion", plural halakim
חלקים) is a unit of time used in the calculation of the Hebrew
calendar. The hour is divided into 1080 halakim. A helek is
31/3 seconds or 1/18 minute. The helek derives from a small
Babylonian time period called a she, meaning '"barleycorn",
itself equal to 1/72 of a Babylonian time degree (1° of
celestial rotation).
360 degrees x 72 shes per degree / 24 hours = 1080 shes per
hour.
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