Indian astronomers left behind their evidence of contribution in the earliest textual mention, which is given in the religious literature of India. During the 1st millennium BCE, Jyotia Vedanga and other auxiliary branches of learning called Vedangas began to take shape and the following centuries a number of Indian astronomers studied various aspects of astronomical sciences and global discourse along with other cultures followed. A number of instruments were used in Indian astronomy, which were also applied for calendrical studies.

Lagadha, the earliest Indian astronomer of 2nd-1st millennium BCE wrote the earliest astronomical text, named Vedanga Jyotisha that dates back to around 1200 BC, and offer details of the astronomical attributes generally applied for timing social and religious events. The Ved?nga Jyotisha provides astronomical calculations, calendrical studies, and establishes rules for empirical observation. Since the texts written by 1200 BCE were closely associated with Indian astrology and several important aspects of the time and seasons, including lunar months, solar months, and their adjustment by a lunar leap month of Adhimasa. Ritus and Yugas are also described in this text that is revered by all the Indian astronomers.

Aryabhata was the author of the Aryabhatiya and the Aryabhatasiddhanta, which, according to Hayashi circulated mainly in the northwest of India and, through the Sasanian dynasty had a philosophical influence on the development of Islamic astronomy. Its contents are reflected in the works of Varahamihira, Bhaskara I, Brahmagupta and others. It is one of the earliest astronomical works in India to assign the start of each day to midnight.

Brahmagupta is one of the most renowned Indian astronomers, who flourished around 598 CE. He dealt with both Indian mathematics and astronomy. In Khandakhadyaka (A Piece Eatable, 665 CE), Brahmagupta included Aryabhata`s idea of another day beginning at midnight. Varahamihira of 505 CE was an Indian astronomer and mathematician who studied and Indian astronomy as well as the many principles of Greek, Egyptian, and Roman astronomical sciences. His Pancasiddh?ntik? is a dissertation and compendium drawing from several knowledge systems. Another well-known name amongst the Indian astronomers is Nilakanthan Somayaji who reached prominence in 1444-1544 CE from the Kerala School of astronomy and mathematics. In his Tantrasangraha, he revised Aryabhata`s model for the planets Mercury and Venus. His equation of the center for these planets remained the most accurate until the time of Johannes Kepler in the 17th century. Some other honoured Indian astronomers are Lalla, Bh?skara II, ?ripati, Mahendra Suri and Acyuta Pis?rati.