The reply also stated: “Next NavIC satellite NVS-03 is ready for launch and two more satellites NVS-04 and NVS-05 are in advanced stage of realisation.”For the first time since positioning data from one of its satellites was lost in March, the government has accepted in the parliament that the seven-satellite navigation constellation (NavIC) can no longer independently aid people in navigation.The Indian Space Research Organisation (ISRO) earlier this year informed that IRNSS-1F satellite, which was launched in March 2016, completed its designed mission life of 10 years and the on-board atomic clock stopped functioning.“…presently the NavIC constellation has three satellites for providing PNT (Positioning, Navigation, Timing) services — IRNSS-1B, IRNSS-1I and NVS-01. To provide basic positioning service, minimum four operational satellites are required in orbit. Hence, the NavIC constellation cannot provide standalone positioning service, however timing service is functional,” union minister of state for space Dr Jitendra Singh replied in a written answer in Parliament.The reply said that the armed forces continue to use NavIC signals as part of the multi-constellation GNSS — Global Navigation Satellite System that uses data from US’ GPS, EU’s Galileo, and Russia’s Glonass among others to navigate.When asked whether it compromises accuracy for navigation or real-time mapping, the reply stated: “Since NavIC is being used in multi constellation environment for most of the use-cases, there is no vulnerability for the users.”While end-user applications were developed for utilising NavIC signals in aviation, shipping, railways, and even in everyday cell phones, all of these devices carry a GNSS receiver, meaning they can continue to get positioning data from other constellations.The reply also stated: “Next NavIC satellite NVS-03 is ready for launch and two more satellites NVS-04 and NVS-05 are in advanced stage of realisation.”Story continues below this adThe constellation can still provide accurate time signals for digital devices as well as broadcast emergency messages.The Indian Regional Navigation Satellite System (IRNSS) — also referred to with the operational name of Navigation with Indian Constellation (NavIC) — was planned to be a seven-satellite system to provide positioning data over the Indian subcontinent and 1500 km around it. Ever since its inception, however, it has been plagued by problems affecting its positioning data.Anonna Dutt is a Principal Correspondent who writes primarily on health at the Indian Express. She reports on myriad topics ranging from the growing burden of non-communicable diseases such as diabetes and hypertension to the problems with pervasive infectious conditions. She reported on the government’s management of the Covid-19 pandemic and closely followed the vaccination programme. Her stories have resulted in the city government investing in high-end tests for the poor and acknowledging errors in their official reports. Dutt also takes a keen interest in the country’s space programme and has written on key missions like Chandrayaan 2 and 3, Aditya L1, and Gaganyaan. She was among the first batch of eleven media fellows with RBM Partnership to End Malaria. She was also selected to participate in the short-term programme on early childhood reporting at Columbia University’s Dart Centre. Dutt has a Bachelor’s Degree from the Symbiosis Institute of Media and Communication, Pune and a PG Diploma from the Asian College of Journalism, Chennai. She started her reporting career with the Hindustan Times. When not at work, she tries to appease the Duolingo owl with her French skills and sometimes takes to the dance floor. ... Read More Tags:Indian Space Research Organisation (ISRO)ISRO