Former space scientist and Indian Space Research Organisation (ISRO) Chairman Udupi Ramachandra Rao passed away at his residence in Bengaluru. The 85-year-old had served as the organisation's head from 1984-1994. He had launched India's first satellite Aryabhatta in 1975.

"Rao passed away at his residence in the city`s eastern suburb at around 3 a.m., after prolonged illness and age-related health issues," the Indian Space Research Organisation official told IANS.

Prime Minister Narendra Modi tweeted:

Saddened by demise of renowned scientist, Professor UR Rao. His remarkable contribution to India's space programme will never be forgotten. — Narendra Modi (@narendramodi) July 24, 2017

Rao was currently the Chairman of the Governing Council of the Physical Research Laboratory at Ahmedabad and Nehru Planetarium at Bengaluru and chancellor of Indian Institute for Space Science and Technology (IIST) at Thiruvananthapuram.

Rao was the recipent of Padma Bhushan in 1976 and Padma Vibhushan in 2017.

He was the first Indian to be inducted in the Satellite Hall of Fame - Washington in 2013 and in International Astronautics Federation (IAF) in 2016.

Rao completed his B.Sc from Madras University, M.Sc from Banaras Hindu University and Ph.D from Gujarat University under the guidance of Dr. Vikram Sarabhai.

He taught at MIT and University of Texas at Dallas, before returning to India in 1966 as a professor at the Physical Research Laboratory, Ahmedabad.