Hitting a century, ISRO launches 100th satellite from Sriharikota

This was ISRO’s first launch in 2025 and after Dr V Narayanan took over as the space agency’s chairman earlier this month.

Chennai: Scripting history, the Indian Space Research Organisation (ISRO) on Wednesday launched its landmark 100th satellite from the Satish Dhawan Space Centre (SDSC) in Sriharikota near here with the successful lift-off of navigation satellite NVS-02.

GSLV-F15, the 17th flight of Geosynchronous Satellite Launch Vehicle (GSLV) and 11th flight with indigenous Cryo stage, took off from the second launchpad of the SDSC at 6.23 am. Nineteen minutes later, the GSLV-F15 with indigenous Cryogenic stage placed the NVS-02 satellite weighing nearly 2,250 kg into the desired Geosynchronous Transfer Orbit.

Today’s successful mission — the first in 2025 and under the leadership of new ISRO chairman Dr V Narayanan — is a major leap in ISRO’s journey of launching satellites from Andhra Pradesh’s Sriharikota, 110 km from here.

SLV-E-01 carrying the Rohini Technology payload with former President A P J Abdul Kalam as the mission director was the first satellite to be launched from Sriharikota on August 10, 1979, which was partially successful.

“I am extremely happy to announce that the first launch of 2025 has been successfully accomplished. This is a very significant milestone. GSLV-F15 launch vehicle precisely injected the navigation satellite in the intended required (GTO) orbit,” a beaming Narayanan, who was congratulated and hugged by his colleagues, announced.

NVS-02 is the second satellite in the NVS series which will enhance the country’s navigational capabilities and is part of India’s Navigation with Indian Constellation (NavIC). The satellite will provide accurate position, velocity and timing (PVT) service to users in India as well as to regions extending about 1,500 km beyond the Indian land mass.

At present, four navigation satellites are operational and the ISRO has approvals to build three more. “We are planning to launch one more satellite in the next five to six months,” Narayanan added.

Key applications of NavIC include terrestrial, aerial, and maritime navigation, precision agriculture, geodetic surveying, fleet management, location-based services in mobile devices, orbit determination for satellites, Internet-of-Things (IoT) based applications, emergency services, and timing services.

Narayanan said the NVS-02 satellite incorporates the second indigenous Atomic clock, which is a “shining example” of 'Make in India' in the critical technology department. “Many applications based on NavIC, spanning from strategic issues to tracking of shipping vessels to time synchronisation to train tracking have been accomplished,” the ISRO chief added.

The satellite developed by U R Rao Satellite Centre will provide two types of services, namely, Standard Positioning Service (SPS) and Restricted Service (RS), while its SPS provides a position accuracy of better than 20 m (2σ) and timing accuracy better than 40 ns (2σ) over the service area.

NVS-01 is the first of the second-generation satellites which already flew with an indigenous atomic clock on May 29, 2023. Like its predecessor, NVS-02, the second satellite in the NVS series is configured with Navigation payload in L1, L5 and S band in addition to ranging payload in C-band.

Narayanan said the ISRO has so far developed six generations of launch vehicles, the first one being under Satish Dhawan with Abdul Kalam as its project director.

Since 1979, the ISRO has conducted 99 launches with the space agency’s trusted workhorse PSLV carrying out 62 launches, followed by GSLV (16), LVM3 (7), ASLV (4), SLV (4), SSLV (3), and test missions such as crew escape system, scramjet engine, and RLV-TD.

Some of the key missions of the ISRO include the Chandrayaan series which has so far sent three unmanned missions to the moon, earth and navigation satellites, the solar mission known as Aditya L1, and a MARS Orbiter mission.

Additionally, as many as 537 launches have taken place at the Sounding Rocket Complex in Sriharikota after it became operational on October 9, 1971, with the flight of ‘Rohini-125’, a small sounding rocket.

Sriharikota, the spindle shaped island in Andhra Pradesh’s Nellore district situated in the backwater Pulicat Lake and sandwiched by Buckingham Canal on the West and Bay of Bengal on the East, was chosen by the Union Government in 1969 for setting up the country’s rocket launch station.

ISRO is now building its second launchpad complex in Kulasekarapattinam in Thoothukudi district in Tamil Nadu exclusively for launching small satellites which is geographically advantageous for the country, while the SDSC complex in Sriharikota will also get a third launch pad very soon.

Scientists say the Kulasekarapattinam spaceport will help save fuel as satellites launched from here can directly travel towards south unlike those launched from Sriharikota which fly in the southeast direction after liftoff from the Sathish Dhawan Space Centre to avoid flying over Sri Lanka and takes a sharp manoeuvre towards the South Pole. The spaceport will be operationalised in the next two years.