Of the 31 communication satellites produced by ISRO, 19 have been launched on Ariane rockets, 10 on the GSLV, one on the PSLV and, earlier this month, one on the GSLV Mk III.
The GSAT-17, launched on an Ariane 5 rocket today, is the thirty-first communication satellite to have rolled off of the Indian Space Research Organisation’s (ISRO’s) production lines.
The very first one was APPLE, the ‘Ariane Passenger Payload Experiment’, which the European Space Agency launched for free on their fledgling Ariane 1 rocket 36 years ago. This experimental spacecraft was, as an ISRO brochure noted at the time, “conceived as a stepping stone towards future operational national communication satellites which can provide communication, direct TV broadcast and meteorological services from a geostationary orbit.”
The first such operational communication satellite designed and built by ISRO, INSAT-2A, went into space, again on an Ariane rocket in July 1992. Before that, four INSAT-1 satellites were made for ISRO on contract by a US company then known as the Ford Aerospace Communications Corporation.
Of the 31 communication satellites that ISRO has turned out so far, 19 have been sent up on Ariane rockets, 10 on the Geosynchronous Satellite Launch Vehicle (GSLV), one on the Polar Satellite Launch Vehicle (PSLV) and, earlier this month, GSLV Mk III successfully launched its first such satellite. Three of the satellites that went on the GSLV were lost on account of launch failures and one had to be written off after becoming stranded in a lower-than-intended orbit.
As the graph above indicates, this year is likely to see ISRO launching a record five communication satellites. Three have already been sent into space in rapid succession: the GSAT-9 (or South Asia Satellite) in May, followed by the GSAT-19 on the Mk III and now the GSAT-17 this month.
The GSAT-6A, intended for the defence services, will be launched onboard a GSLV Mk II rocket, possibly in September this year. The GSAT-11, which will be the heaviest communication satellite built thus far by ISRO (weighing about 5.8 tonnes) is expected to be launched on an Ariane 5 rocket at the end of 2017.
Gopal Raj is a science journalist based in Thiruvananthapuram. He has written extensively about the Indian space programme, including a book, Reach for the Stars: The Evolution of India’s Rocket Programme.
This article was originally published by New Space India and has been republished here with permission.