The begining of the tradition of astronomy is also as ancient (old) as the period of Vedas. Numerous facts about astronomy is found occasionally described in Vedas. Culture in the Vedic period was 'Yagnapradhan' - Yagna priented. To decide proper time to conclude the sacred fire much discussion used to be held. In this situation principles of astronomy were practiced. Today also the works/books describing the accepted principles are available.
Astrology as such is considered to be a part of Vedas. Astronomy is an integral part of astrology. The minutest description of the sun, the moon, the planets, the stars. etc and the tradition of thinking of their movements starts from the period of Vedas. There is a mention twenty seven constellation, stars, of Saptarshi (group of seven stars) and planets in Rugveda. There is a description of planets in Yajurveda. There is a very long story in Taitiriyasamhita about the liking of moon the planet Rohini. There is a mention odf Dhruv i.e. North star and Arundhati in Aslayan Sutra Description of planets comet and stars at many places in Mahabharat.
Discussion thinking of astronomy became more clear with the passage of time. The tradition of astronomy after that of Ved-vedang literature is furthered by Scholars like Aryabhatta, Bhaskaracharya, Varahmihir, etc. The principles laid down by them are world famous. Out of them Varahmihir is the most outstanding scholar.