New Delhi, March 14 -- India's indigenous GPS alternative, NavIC, has suffered setback with the loss of satellite IRNSS-1F after its final atomic clock stopped functioning on Friday.

With this development, only three satellites, IRNSS-1B, IRNSS-1L and NVS-01, remain operational for providing positioning, navigation and timing (PNT) services. This poses a challenge as a minimum of four satellites is reportedly required to ensure complete navigation coverage across India and surrounding areas.

"IRNSS-1F satellite launched in March 2016 has completed its design mission life of 10 years on 10th March 2026," Indian Space Research Organisation (ISRO) stated on its website, adding, "On 13th March 2026, procured on-board Atomic clock stopped fu...