This is the first publication of the astronomical diary BM 30617 from Babylon. This clay tablet shows an example of “preliminary diaries”, which record primary observations of the sky and, if any, the Euphrates for one month or less. The cuneiform text of BM 30617 shows the primary day-by-day observations of the sky over the first four days of the Babylonian month IX (Kislīm). The recorded phenomena are dated to an unknown year during the joint kingship of Antiochus and his son (or stepson), also named Antiochus, of the Seleucid dynasty. Some clues in the diary, however, help us to narrow down the candidates for the year to which our month IX belongs.
