ISRO-GISAT-1 A Launch ISRO Readies Gisat-1A Launch as replacement for GISAT-1

By R Anil Kumar

Bengaluru. The Indian Space Research Organisation (ISRO) is preparing to launch Gisat-1A, also designated EOS-05, as a replacement for the lost Gisat-1 satellite. The spacecraft is expected to reach India’s spaceport shortly, marking a critical step in restoring near real-time Earth observation capability.

Background of the Gisat Programme

Gisat-1A follows the unsuccessful GSLV-F10 mission of August 12, 2021, when a cryogenic upper stage anomaly prevented the original Gisat-1 (EOS-03) from reaching orbit. That failure came after two earlier launch postponements in 2020 and early 2021 due to technical issues. Since then, ISRO has undertaken multiple design reviews and validation exercises to ensure mission readiness.

Capabilities and Strategic Relevance:

The 2.2-tonne class Gisat-1A satellite is designed to provide frequent, near real-time imaging of large regions of interest. While primarily a civilian Earth observation satellite, it holds strategic value by enabling all-weather, cloud-free monitoring of the Indian subcontinent. Its data will support agriculture, forestry, mineral exploration, disaster management, oceanography, snow and glacier studies, and cloud property analysis, while also aiding operational planning by India’s armed forces.

Launch Preparations and Timeline:

The satellite has completed key milestones at the UR Rao Satellite Centre in Bengaluru and is awaiting final authorisation to be transported to the Satish Dhawan Space Centre.   ISRO Chairman V Narayanan speaking to R. Anil Kumar has confirmed that the satellite is under review. A Notice to Airmen has already been issued for the GSLV-F17 mission, with a tentative launch window between February 20 and March 5.

Important Facts:

• Gisat-1A is also known as EOS-05 and replaces the failed EOS-03 mission.
• The satellite will be launched aboard the GSLV-F17 rocket.
• Gisat satellites provide near real-time geo-imaging from geostationary orbit.
• The 2021 GSLV-F10 failure was due to a cryogenic upper stage anomaly.

Lessons From Recent Launch Failures

ISRO’s heightened caution follows two recent PSLV failures that resulted in the loss of EOS-09 (RISAT-1B) and DRDO’s Anvesha (EOS-N1), both strategically important satellites.  Since the 2021 cryogenic failure, GSLV vehicles have completed four successful missions, including the launch of the NISAR satellite in July 2025. The Gisat-1A mission is therefore viewed as a crucial test of confidence for India’s heavy-lift launch programme and its Earth observation roadmap.