Etymologically the word “Molad” is about birth. The moon is reborn each month after its disappearance at the end of the previous month. That birth is the appearance of the Crescent New Moon.
Far removed from that birth by over 2800 years is the Molad of today which is simply the result of a mathematical expression.
The start of the series of Moladot was Fri, July 16, 791 BCE 18:00, Shabbat, zero hours, zero parts.
For every lunar month afterwards 29 days, 12 hours, and 793 parts (out of 1080) were added. This brought the Molad of Tishrei for Hebrew Year 5775 (2014-2015) to Wed, Sep 24, 2014 AD 8:14:00, 14 hours , 339 parts.
The time constant added each month came from ancient Babylonian Science. The Babylonians had been recording astronomical data for thousands of years and recording in on clay tablets which have been found in the sands of Iraq. In the 8th Century BCE patterns had begun to emerge that let the Chaldeans come to the conclusion that the average period of the Synodic Month was 29;31:50:08:20 days sexagesimal. That is the same as the Moladic Constant — 29 days, 12 hours, and 793 parts.
Because this Moladic Constant is 532 milliseconds greater that the actual value of an average Synodic Month as determined by present day astronomy over the 2804 years the average Molad has become closer to when the New Moon is actually seen by 5 hours and 7 minutes. This still represents a phenomenal level of accuracy.