Praful D. Bhavsar, a veteran of the Indian Space Research Organisation (ISRO) who passed away in Ahmedabad aged 97 on Saturday, had played an instrumental role in the very first sounding rocket launch from Thumba on November 21, 1963.
This, in the public mind, was the event which marked the beginning of India’s glittering space saga.
Dr. P.D. Bhavsar was project scientist and principal investigator for that first rocket-borne experiment from the Thumba Equatorial Rocket Launching Station (TERLS) which used an American-made Nike-Apache sounding rocket and a sodium vapour payload supplied by France.
This experiment involved photographing the sodium vapour cloud released against the twilight sky once the sounding rocket reached an altitude of about 100 km. The cameras were located at Kanyakumari, Kodaikanal, Palayamkottai and Kollam.
“It was important that these four cameras were synchronised with an accuracy of plus or minus one second. This might seem trivial today but it was indeed a very difficult task with the meagre communication facilities available then. Synchronisation was accomplished through dedicated telephone lines with fixed-time calls,” the book ‘A Brief History of Rocketry in ISRO’ authored by ISRO veterans P.V. Manoranjan Rao and P. Radhakrishnan notes.
“The movement of the cloud could be used to measure the neutral winds,” Dr. Rao told The Hindu on Sunday.
He described Dr. Bhavsar as a ‘grand old man’ of the space agency, a pioneer who was there from the early days of the space programme and lived to see its grand evolution, which spans the recent Chandrayaan-3 mission and the launch of the Aditya-L1 solar probe. “He was working in the area of cosmic rays. The subject of space physics was brought to Thiruvananthapuram by Dr. Bhavsar,” Dr. Rao said.
Dr. Bhavsar, who had joined the Physical Research Laboratory (PRL), Ahmedabad, as a doctoral student of Vikram Sarabhai, held many important posts in the space programme, apart from leading the team which performed the first rocket experiments for measuring neutral atmospheric winds in the equatorial region.
He played an important role in the establishment of the Space Physics Division (SPD), which he headed. SPD later became the Space Physics Laboratory (SPL) under the Vikram Sarabhai Space Centre (VSSC),Thumba.
Among other things, he was the third director of the Space Applications Centre (SAC), scientific coordinator of ISRO from 1967 to 1975 and scientific secretary, ISRO, from 1973-75.