Friday’s pre-dawn launch follows an eight-month gap.
ISRO Launches EOS-05 Satellite on GSLV-F17 from Sriharikota
Sriharikota: India’s space programme marked an important milestone early Friday as ISRO successfully launched its advanced Earth observation satellite, EOS-05, from the Satish Dhawan Space Centre in Sriharikota.
The launch took place at 2:55 AM on September 4 from the second launch pad, following a smooth 27-hour countdown that began at 11:30 PM on Wednesday. Despite the early morning hour and rain, the excitement around the mission remained high, with members of the public turning up to watch and cheer the launch.
A GSLV-F17 rocket carried the 2,367-kg EOS-05 satellite toward its planned Sub-Geosynchronous Transfer Orbit (Sub-GTO). The satellite is designed to provide near real-time Earth imagery, with applications expected across several important sectors, including agriculture and disaster management.
EOS-05 is particularly significant because it is India’s first imaging satellite intended for the geosynchronous orbit. Unlike many Earth observation satellites that operate in low Earth orbit, EOS-05 is expected to operate at an altitude of around 36,000 km above Earth.
At that height, the satellite will travel at a speed matching Earth’s rotation. This allows it to remain over a similar region of the planet, making it useful for continuous observation and monitoring.
A powerful GSLV missionThe GSLV-F17 is the 19th flight of India’s Geosynchronous Satellite Launch Vehicle. The three-stage rocket stands 51.7 metres tall and has a lift-off mass of around 420.5 tonnes.
Its third stage uses a cryogenic engine, a technology that plays a crucial role in carrying heavy payloads to higher orbits. The EOS-05 satellite was positioned inside the rocket’s nose cone for its journey into space.
The mission also carries added significance because it is intended as a replacement for the unsuccessful GSLV-F10/EOS-03 mission in 2021.
That earlier mission was aborted about 307 seconds after launch. An investigation into the post-flight data later pointed to an anomaly in the Cryogenic Upper Stage as the reason for the failure.
For ISRO, Friday’s launch therefore represented more than another routine mission. It came after a difficult period in which two previous launch attempts had faced setbacks.
Return to launch activityThe EOS-05 launch comes after a gap of nearly eight months.
On January 12 this year, ISRO’s PSLV-C62 mission, carrying 16 satellites, failed to place its payloads into their intended orbits after an anomaly occurred in the rocket’s critical third stage. It was ISRO’s only launch of the year before Friday’s mission.
Another setback occurred in May 2025, when the PSLV-C61/EOS-09 mission failed because of a motor pressure issue. A drop in chamber pressure was reported during that mission.
Against this backdrop, the successful GSLV-F17/EOS-05 launch offers a significant boost to ISRO’s ongoing efforts and demonstrates the importance of carefully reviewing earlier failures before returning to flight.
The mission had also attracted considerable attention ahead of launch. Just days before liftoff, ISRO Chairman V. Narayanan visited the Tirumala Tirupati Lord Venkateshwara Swamy temple and offered prayers for the mission’s success.
With EOS-05 now heading toward its intended orbit, the focus will turn to its deployment and the beginning of its Earth observation work. If it performs as planned, the satellite could provide valuable data for monitoring agriculture, responding to disasters and improving the country’s ability to observe changes on Earth.
ISRO launched the EOS-05 Earth observation satellite from Sriharikota.
The GSLV-F17 rocket lifted off at 2:55 AM on September 4 .
The satellite weighs approximately 2,367 kg .
EOS-05 is designed for operation in geosynchronous orbit .
It will operate at an altitude of roughly 36,000 km above Earth.
The satellite is expected to support agriculture and disaster management .
GSLV-F17 is the 19th flight of India’s Geosynchronous Satellite Launch Vehicle.
The rocket stands 51.7 metres tall and has a lift-off mass of about 420.5 tonnes .
The mission follows the unsuccessful GSLV-F10/EOS-03 mission of 2021 .
ISRO also faced setbacks with the PSLV-C61/EOS-09 mission in May 2025 and PSLV-C62 in January 2026.
The successful launch marks an important return to major launch activity for ISRO.