 Later medieval era texts such as the "Yavana-jataka" and the "Siddhanta" texts are more astrology-related.The field of Jyotisha deals with ascertaining time, particularly forecasting auspicious day and time for Vedic rituals.The field of Vedanga structured time into "Yuga" which was a 5-year interval, divided into multiple lunisolar intervals such as 60 solar months, 61 savana months, 62 synodic months and 67 sidereal months.