Abū Maʿshar al-Balkhī, Jaʿfar b. Muḥammad b. ʿUmar (19 Ṣafar 171–28 Ramaḍān 272/10 August 787–9 March 886), was a Persian astrologer. His name is recorded as Apomasar, Albumasar or such like names in old and modern European sources (Pingree, EIR, 1/337). The above date of birth, which is derived from the astrological birth chart in Abū Maʿshar's Aḥkām taḥwīl sinī al-mawālīd, is not entirely certain (Ullmann, 316). There is also some doubt over his date of death: in contrast to Ibn al-Nadīm (p. 335)…