ISRO ended 2024 on a high with the successful launch of its 99th mission – Polar Satellite Launch Vehicle or PSLV-C60 – which is carrying two important pilot missions – Spadex and POEM-4. Although these experiments will continue in the new year, the Indian space agency wants to ride the high wave and has made a big announcement.
Indian Space Agency Chairman S Somnath announced that the first mission of 2025 will be ISRO’s historic 100th mission. It will take place in January, he confirmed, but did not say what date it was being planned.
However, he said that the 100th mission will be aboard the Geosynchronous Satellite Launch Vehicle or GSLV Mk-II rocket. The objective of the mission will be to link the Indian satellite navigation system being established and expanded over time by ISRO. The name of this mission will be GSLV-F15/NVS-02 mission. The payload will be the IRNSS-1K satellite, part of India’s navigation satellite constellation.
NVS or Navigation Satellite is part of the Indian Constellation or Navigation with Navigation – India’s version of the Global Navigation Satellite System or GNSS – similar to the Global Positioning System or GPS that is often used around the world.
Also read: ISRO’s Spadex mission is the first step for India to set up its own space station
GSLV-F15/NVS-02 Mission and its Objectives
GSLV-F15 will be the 17th flight of India’s Geosynchronous Satellite Launch Vehicle or GSLV. This will also be the 8th operational flight (11th overall flight) of GSLV with India’s indigenous cryogenic stage.
The main objective of the mission under the NavIC system will be to assist:
- precision military activity
- strategic applications
- Terrestrial, aerial and marine navigation
- precision agriculture
- geodetic survey
- emergency services
- fleet management
- Location-based services in mobile devices
- orbit determination for satellites
- marine fishing
- Timely services for financial institutions, power grids and other government agencies
- Internet-of-Things (IoT) based applications
All about NVS-02/IRNSS-1K satellite
NVS-02, as the name suggests, will be the second in the series of second generation navigation satellites and the ninth satellite in navigation with the Indian Constellation (NavIC). Like its predecessor – NVS-01 – the NVS-02 will likely carry two types of payloads – navigation payload and ranging payload.
Image Credit: ISRO
The navigational payload is what transmits the signal to users on Earth. It does this by using three bands in the spectrum – L1, L5 and S band. Since time is relative, and many factors affect it, to know the exact time, an atomic clock is mounted on this payload. This is usually a rubidium atomic clock. The rubidium atomic clock measures the length of a second by counting the oscillations of rubidium-87 atoms. These clocks are so powerful that they have an accuracy of about three parts in 10 quadrillion, meaning they can keep time to within a second for over 100 million years.
The ranging payload consists of a transponder. It helps the navigation satellite to transmit time-stamped navigation signals to receivers at ground stations. This information is processed at the end-user stage to obtain their exact position, speed and time. This helps in providing uninterrupted and non-stop service irrespective of the weather conditions on earth.
NavIC second generation satellites have a more robust encryption system to keep all communications completely secure.
Like America’s GPS, India’s NavIC also has dual use – civilian and military. NavIC was earlier named IRNSS or Indian Regional Navigation Satellite System, which had a very limited coverage area.
There are currently four global navigation systems – GPS from the United States, GLONASS from Russia, Galileo from the European Union, and BeiDou from China. India’s NavIC and Japan’s QZSS are still only regional, but may become global in the future.
The last GSLV mission was the GSLV-F14/INSAT-3DS mission, which was launched on February 17, 2024. It placed the INSAT-3DS satellite payload into a GTO or Geosynchronous Transfer Orbit. The last GSLV mission used for NavIC was in May 2023, when ISRO launched NVS-01, the predecessor of NVS-02. The name of this mission was GSLV-F12/NVS-01 mission.
