an announcement of the exact date and time of the new moon, referred to as the molad, or "birth". Rosh Chodesh Tishrei (which is also Rosh HaShana) is never announced, although according to the fixed Jewish calendar, it is the determining factor for all of the postponements (Dehioth) which determine when each Rosh Chodesh is actually observed. Traditional observances On Rosh Chodesh, a prayer Ya'a'le Ve-Yavo is added to the Avodah blessing of the Amidah. In the morning service "half Hallel" (Psalms 113–118, with two paragraphs omitted) is recited (except on Rosh Chodesh Tevet, which is during Chanukkah, when Full Hallel is recited). The Torah is read, specifically which includes the sacrifices of Rosh Chodesh. An additional prayer service, called Mussaf, is added to commemorate the Rosh Chodesh sacrifices in the Temple. Its middle blessing begins "Roshei Chadashim". After the service, many recite Psalm 104. If Rosh Chodesh falls on Shabbat, the regular Torah reading is supplemented with a reading of Numbers 28:9-15. The German custom is to sing the Half Kaddish preceding Maftir to a special tune. The regular Haftorah is replaced by a special Rosh Chodesh Haftorah. The Mussaf prayer is also modified when Rosh Chodesh falls on Shabbat. The central benediction is replaced with an alternate version (Ata Yatzarta) that mentions both the Shabbat and Rosh Chodesh. If Rosh Chodesh falls on a Sunday, a different Haftarah, Mahar Chodesh ("Tomorrow is the New Moon", I Samuel 20:18-42) is read. Kiddush Levanah is recited soon after Rosh Chodesh, typically on the first Saturday night after Rosh Chodesh. Many have a custom to eat a special meal in honor of Rosh Chodesh, as recommended by the Shulchan Aruch. This gives one the opportunity to recite the Ya'a'le Ve-Yavo in Birkat Hamazon. Some Hasidic Jews sing Psalm 104 during this meal. Work Jews nowadays generally treat Rosh Chodesh as barely different from any other weekday (except for expansion of the prayer service). The Torah does not prohibit work (melacha) on Rosh Chodesh, and the Talmud states that work is permitted on Rosh Chodesh. The Jerusalem Talmud states that women refrain from work on Rosh Hodesh, but only by custom as opposed to law. This custom is recorded in the Shulchan Aruch, but does not seem to be commonly practiced in modern times. Yet for much of early Jewish history, Rosh Chodesh was observed much more seriously. In some Biblical sources,