What is "varahamihira"

Varāhamihira (505–587 CE), also called Varaha or Mihir, was an Indian astronomer, mathematician, and astrologer who lived in Ujjain. He was born in Avanti (India) region, roughly corresponding to modern-day Malwa, to Adityadasa, who was himself an astronomer. According to one of his own works, he was educated at Kapitthaka. He is considered to be one of the nine jewels ( Navaratnas) of the court of legendary ruler Yashodharman Vikramaditya of Malwa.