Molad Amiti (True Molad)
The molad amiti (true molad), which has no relevance to the Hebrew calendar, is the time at which the actual astronomical lunar conjunction occurs, often expressed either as the mean solar time in Jerusalem (Universal Time + 2h 20m 56s or simply + 2h 21m) or as the clock time in Israel. If the moment is desired for ritual or social purposes then it may be best to express it in terms of the local clock time.
On average the traditional molad of the Hebrew calendar is currently >2 hours late, and there are substantial periodic variations in the astronomical lunar cycle length, such that in the present era it varies over a 28-hour span ranging from 12 hours early to 16 hours late, compared to the Jerusalem mean solar time molad amiti, if all months are included in the evaluation. If the evaluation is limited to a single Hebrew month, however, for example Tishrei, then the portion of the variations that are due to Earth orbital eccentricity are for the most part eliminated and the average has an offset that is month-specific, such that presently the molad of Tishrei varies over about a 20-hour span ranging from 4 hours early to 16 hours late.
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