India’s space agency ISRO is all set to launch IRNSS-1H, our eighth navigation satellite in the series. The satellite will blast off in PSLV-C39 today at 7 PM. The countdown for the launch began 29 hours before, that is on Wednesday. The launch will happen at Sriharikota, Andhra Pradesh from Second Launch Pad (SLP) of the Satish Dhawan Space Centre (SDSC) SHAR. The launch vehicle will carry the Indian Regional Navigation Satellite System (IRNSS) satellite which weighs 1425 kgs. It is meant for navigation based applications. The 8th satellite of the IRNSS series will go into a Sub-Geosynchronous Transfer Orbit (Sub-GTO).
PSLV-C39, like the previous six launches of IRNSS satellites, will use the ‘XL’ version of the PSLV equipped with six strap-ons, each carrying 12 tonnes of propellant. A report in The Indian Express had earlier said that the IRNSS-1H will replace the IRNSS-1A. The latter is a part of a seven-satellite Indian navigation constellation which failed because of deficiencies in three atomic clocks on the satellite that are important for providing positional information to users on earth. IRNSS-1H satellite will be more flexible and compatible with its service with the satellites, which are in orbit. It will join the navigation services constellation and IRNSS-1A will now be used for messaging services.
Meanwhile, ISRO’s Vikram Sarabhai Space Centre Director K Sivan said, “The spare or standby satellite will also make up for the non-functioning of the three rubidium atomic clocks on board the first one (IRNSS-1A) and one each in the other two NavIC satellites.”
Who built the IRNSS-1H? The spacecraft was built and tested by ISRO along with a consortium of six small and medium industries. The IRNSS is an independent regional navigation satellite system developed by India on par with US-based GPS.
What will IRNSS-1H do? It will offer services like terrestrial and marine navigation, disaster management, vehicle tracking and fleet management, navigation aid for hikers and travellers, visual and voice navigation for drivers. This system was named ‘NavIC’ (Navigation with Indian Constellation) by Prime Minister Narendra Modi.
What is the history of IRNSS-1H? India had launched seven satellites since 2013 in its IRNSS series in totality. IRNSS-1G was launched on April 28, 2016. IRNSS-1F on March 10, 2016. IRNSS-1E on January 20, 2016. IRNSS-1D on March 28, 2015. IRNSS-1C on October 16, 2014. IRNSS-1B on April 4, 2014. IRNSS-1A on July 1, 2013. ISRO had planned for nine satellites in its Indian Regional Navigation Satellite System which would cost Rs 1,420 crore. While seven satellites were to form the Navigation Indian Constellation or NavIC, two satellites were meant to be replacements.