Sriharikota: Indian Space Research Organisation (ISRO) successfully launched the IRNSS 1I navigation satellite from the Satish Dhawan Space Centre at Sriharikota, Andhra Pradesh, on the 43rd flight of the Polar Satellite Launch Vehicle (PSLV), early Thursday morning.
The IRNSS 1I mission is critical for the space agency as it is ISRO's second attempt to replace the IRNSS 1A satellite, after the failure of the IRNSS 1H mission in August ISRO's last mission is in jeopardy as the space agency lost contact with GSAT 6A a few days after launch on March 31.
The Indian Regional Navigation Satellite System (IRNSS) is a constellation of seven satellites that provides indigenously developed regional GPS services called NavIC. The rubidium-based atomic clocks onboard the IRNSS 1 A failed and it was no longer useful for providing navigation services.
Earlier, ISRO Chairman K Sivan told a news paper on the eve of the launch that IRNSS-1I will be the last in the current ‘approved’ navigation satellite series. “There is a plan for a new IRNSS series. We are working on it and will be submitting a proposal before the Centre. It will be a totally new project,” he said. Sivan said it would be an extension of IRNSS project. Currently, various modalities are being working out like on number of satellites, on board technologies etc. “The idea is to improve the accuracy of services further and also have enough back-up satellites in space just in case there is a situation where one stops functioning like it happened with IRNSS-1A.
To a query, he said the new IRNSS series is not meant to extend its coverage beyond the regional boundaries. NavIC is an independent regional navigation satellite system developed by India. It is designed to provide accurate position information service to users in India as well as the region extending up to 1,500 km from its boundary. It will provide two types of services, namely, Standard Positioning Service (SPS) which is provided to all the users and Restricted Service (RS), which is an encrypted service provided only to the authorised users. “This will not change much. It will be only a regional system, but the accuracy will improve,” he said.
If IRNSS-1I is launched successfully on Thursday, it will complete ISRO’s commitment to put seven operational navigation satellites in orbit. Though, the space agency has put seven satellites in operation after successfully launching IRNSS-1G on April 26, 2016, the first satellite of the series IRNSS-1A put into orbit on July 1, 2013 developed trouble with three rubidium atomic clocks on board not functioning. One ground spare, IRNSS-1H was flown as replacement satellite aboard PSLV-C-39 on August 31, 2017, but heat shield separation failed and the satellite failed to deploy. Now, IRNSS-1I is being flown and is the last spare available.
“This NavIC constellation is really going to create history and make innovative applications to the entire community in the ocean-based services especially for the underserved and unserved,” K Sivan, chairman of ISRO, said.
“Very recently using the NavIC applications we have created an app that will be released very soon. I request industry and institutions to come forward to take these applications to the user community.”
The space agency has faced flak from the Comptroller and Auditor General for NavIC still not being fully operational, after more than 10 years of its launch and had cost Rs 1,284 crore.
The 7 IRNSS satellites were launched between 2013 and 2016, with IRNSS 1A being the first. By mid-2016 problems surfaced with atomic clocks on board the satellite. “For a foolproof navigation system that covers the entire country all 7 satellites have to be functional,” Ashish Agarwal, a scientist at National Physical Laboratory, said.
The clocks were manufactured by Spectracom, which is part of the Orolia Group, that is headquartered in the US. The group also supplied clocks for the IRNSS 1I. Though the technology for rubidium clocks has been developed in India, it isn’t proven yet.
The IRNSS 1I was placed in a sub-geosynchronous transfer orbit by the PSLV following which orbit raising manoeuvres that rely on the satellite’s own propulsion system will place it in the targeted geosynchronous orbit at 36,000 km height.
Though the space agency has suffered two setbacks in less than nine months, the launch of two satellites in two weeks comes as a big boost for ISRO. There are nine more launches this year.
“We have lot more challenges for the ISRO community. I am sure they will rise to the occasion,” Sivan said.
Meanwhile, Sivan said the first commercial roll-out of NavIC services is likely by April end. The beneficiaries would be Indian fishermen, especially those who undertake deep sea fishing. A private industry has been roped-in to produce NavIC enabled hi-tech communication gadgets through which fishermen can stay connected upto 1,500 km from the shore without internet or tower connectivity.
The device, which will be fitted to the boats, will use NavIC to lock the location of the boats and periodically update the location to the ground control room. Besides, the fishermen will receive text and video messages about the ocean weather forecast. If a low pressure area has formed in Bay of Bengal and is likely to intensify into a cyclonic storm, fishermen will be alerted ahead of time.
Over the next few days, the progress of the IRNSS 1I mission will be closely watched. In the case of GSAT 6A, the orbit raising manoeuvres could not be completed because of the snapped communication link which meant that Isro could not guide it to its targeted orbit.
Here are 10 facts on the PSLV's IRNSS-1I launch:
- ISRO, the Indian Space Research Organisation, declared the 43rd mission of the PSLV a success after it placed the IRNSS 1I satellite into a precise orbit. The last satellite launch for the satellite-aided navigation NAVIC programme by the PSLV had failed in August 2017.
- After the launch, ISRO Chairman Dr K Sivan said, "I am extremely happy to announce that the 8th navigation satellite of India was launched successfully into the NAVIC constellation. We are moving towards a major goal. This NAVIC constellation will create history."
- India needs seven operational satellites for providing failsafe satellite based navigation. The 1,425-kg satellite was made by the Bengaluru-based Alpha Design Technologies, in collaboration with ISRO.
- The first satellite in the network, IRNSS 1A, ran into trouble when the atomic clocks onboard the satellite failed one after another. Last year, on August 31, ISRO launched a replacement satellite - IRNSS 1H. This time, the rocket failed and the satellite was never placed into orbit. This forced the space agency to launch the IRNSS 1I as a replacement.
- The Indian Regional Navigation Satellite System (IRNSS) has the operational name of NAVIC, an acronym for "Navigation with Indian Constellation". The system is designed to be equivalent to the Global Positioning System or GPS which is owned by the US.
- The NAVIC system is expected to provide location tracking within 20 meters of actual positions, especially in the 1,500 km area around the country's borders - a zone where the maximum threat perception lies. The satellite will have both civilian and military uses.
- The need for an indigenous GPS was felt soon after the Kargil conflict, when India desperately needed the services of a satellite-based navigation system, but did not have one of its own. The American system was not available at the time.
- Only the US and Russia currently have fully operational GPS systems. China and Europe are still in the process of deploying their full systems. A satellite-based navigation system under one's control and command is considered a deep strategic asset.
- The launch of the satellite came two weeks after its GSAST 6A failure. Sources in ISRO have hinted that a "power systems failure" led to the satellite going AWOL.
- A top satellite expert from ISRO confirmed to NDTV that the GSAT 6A was a heavyweight communications satellite and the relatively lightweight IRNSS 1 used a "very different power system", which gave the space agency confidence to march ahead with the launch.
