The successful launch of the NVS-01 by the Indian Space Research Organisation (ISRO) using a GSLV rocket with a cryogenic upper stage is expected to augment the country's regional navigation system, providing accurate and real-time navigation. For the first time, it is equipped with an indigenous onboard atomic clock, which will allow for more accurate orbit-raising procedures, thanks to nanosecond-level precision time measurements. The United States (GPS), Russia (GLONASS), and China (BeiDou) are the only other countries that have their own navigation systems.
This morning was an impressive launch of the NVS-01 satellite, which is fitted with sophisticated navigation payloads in L1, L5, and S bands. It is significant to note the inclusion of a rubidium atomic clock, developed domestically by ISRO, as a part of this second-generation spacecraft. This serves as a powerful demonstration of India's remarkable progress in the field of space exploration and technology.
“In the past, scientists had to rely on imported rubidium atomic clocks to get accurate date and location information. But now, is using an indigenous rubidium atomic clock in this mission. The clock was created by the skilful staff at the Space Applications Centre in Ahmedabad, and it will be part of the satellite, demonstrating India's expertise in space research and development. This milestone advancement reinforces ISRO's dedication to promoting domestic innovation and decreasing the dependence on external elements,” remarked Girish Linganna, Defence and Aerospace expert and MD of ADD Engineering India Limited.
Linganna explained that the importance of this technology is undeniable, given that only a few countries have access to it. “India has recognized the need to meet its needs in terms of positioning, navigation, and timing, specifically in relation to civil aviation and military operations, and thus ISRO has come up with the Navigation with Indian Constellation (NavIC) system,” added Linganna.
This satellite has two solar arrays to provide power up to 2.4 kW, and a Lithium-ion battery to take over during eclipse periods. Both passive and active thermal management is used to regulate temperature, and a unified bi-propellant propulsion system is employed along with a three-axis body stabilized zero momentum system, which utilizes reaction wheels.
This satellite will replace the IRNSS-1G satellite launched in 2016, which is part of a constellation of seven satellites providing navigational services to the Indian region and is expected to have a mission life of 12 years. It is located above the Earth in geostationary orbit and covers India and a region up to 1,500 km beyond the nation's boundary. Weighing 2,232 kg, the NVS-01 satellite will be deployed into a Geosynchronous Transfer Orbit (GTO), which is a highly elliptical orbit with an apogee (farthest point from Earth) of approximately 36,000 kilometres. It will then use its own propulsion system to reach its final geostationary orbit. It will incorporate L1 band signals to widen the services it offers.