Gautama Siddha

Gautama Siddha, (fl. 8th century) astronomer, astrologer and compiler of Indian descent, known for leading the compilation of the Treatise on Astrology of the Kaiyuan Era during the Tang Dynasty. He was born in Chang'an, and his family was originally from India, according to a tomb stele uncovered in 1977 in Xi'an. The Gautama family had probably settled in China over many generations, and might have been present in China prior even to the foundation of the Tang Dynasty. He was most notable for his translation of Navagraha calendar into Chinese. He also introduced Indian numerals with zero (〇) in 718 in China as a replacement of counting rods.