A weekly feature of Torah Tidbits to help clarify practical and conceptual aspects of the Jewish Calendar, thereby better fulfilling the mitzva of HaChodesh HaZeh Lachem...

If this were the Shabbat before the first day of any other month but Tishrei, we'd be benching Rosh Chodesh. The Rosh Chodesh aspect of Rosh HaShana is eclipsed by the essence of Rosh HaShana. This, among other reasons results in our not announcing the coming month, nor its Molad.

Which is ironic, since the Molad of Tishrei is the only one that has a direct relationship to the first of its month. The Molad of Tishrei 5760 computes (using average figures, not actual) to FRI 15h 44m 9p. By the rules of our fixed calendar, Rosh HaShana is fixed on the day of the Molad of Tishrei, unless... Thereare four rules for pushing RH to the day following the Molad of Tishrei - two major and two minor. Both major "push" rules apply to RH 5760, either of which would result in RH being fixed on Shabbat (and Sunday). If the Molad of Tishrei is after noon (which it is), then RH is the following day. If the Molad of Tishreiis a SUN, WED, or FRI (which it is), then RH is fixed on the following day. Either of these rules can be considered "responsible" for RH being SHABBAT (and Sunday) this year. No other Molad determines its month's first day. Only Tishrei's, the one we don't announce.