Astrology for Maecenas

Astronomical themes, with a rather limited scope, were a minor but recurrent element in ancient poetry, and Horace makes considerable use of them in the Odes. Most of the examples involve risings and settings as guides to the time of year, and most are within the range of the phenomena mentioned in Hesiod’s Works and Days. But in Odes 3.29.17-20, for the special interest of Maecenas, Horace breaks new ground by drawing more topical material from the Julian calendar, to remind his friend that it is now July and too hot for working in Rome: the (evening) rising of Cepheus on the 9th, the (morning) risings of Procyon on the 15th and Regulus on the 29th, and the entry of the sun into Leo on the 17th. Such an array of calendaric lore is clearly designed to appeal to Maecenas, who must have had a particular interest in astronomical phenomena.