Lagadha was a Hindu astronomer and astrologer. He is the author of the earliest astronomical text—named Vedanga Jyotisa details several astronomical attributes generally applied for timing social and religious events. One of the major innovations made by Lagadha, was the use of tithi (1 / 30 synodic months) as the standard unit of time. Lagadha also introduced a water clock and the gnomon. The Vedanga Jyotisa had details abot astronomical calculations, calendrical studies, and establishes rules for empirical observation. The Vedanga Jyotisa has connections with Indian astrology and details 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.