The Calendars of Southeast Asia: 5: Eclipse Calculations, and the Longitudes of the Sun, Moon and Planets in Burmese and Thai Astronomy

Many of the calendrical records in Southeast Asia contain information on the longitudes of the Sun, the Moon and the planets—something that is valuable for the dating of these records. Both the Burmese and the Thai use calculation schemes for the longitudes of the Sun, the Moon, and the planets that are almost identical to the original Sūryasiddhānta schemes. After the change to the Thandeikta calendar the Burmese changed some of the parameters involved, in general following those of the modern Sūryasiddhānta.