ISRO Set for First Launch in Eight Months With GSLV F17 on Sept. 4

India's space agency ISRO is preparing for its first rocket launch in eight months, after two consecutive PSLV rocket failures grounded that vehicle. ISRO Chairman V. Narayanan told NDTV that the GSLV F17 rocket is set to lift off on the morning of Sept. 4, carrying the EOS-5 satellite, previously known as GISAT-1A.

Space-debris warning notices put the launch window between Sept. 3 and 25, with liftoff possible between 1:50 a.m. and 6:30 a.m. Indian Standard Time; Sept. 4 is considered the most likely date. ISRO typically begins its countdown for a GSLV launch 27.5 hours before liftoff, with official confirmation released 24 to 12 hours in advance.

EOS-5 will orbit roughly 36,000 kilometers above Earth and continuously observe the country, repeatedly photographing Indian territory through the day. ISRO says the satellite will quickly relay information on fast-changing events such as storms, floods, cloudbursts and forest fires, information that disaster-management agencies, weather forecasters, farming planners and security agencies can use.

The mission is a second attempt at this capability: on Aug. 12, 2021, a GSLV F10 rocket carrying the original GISAT satellite, EOS-03, failed when its cryogenic upper stage malfunctioned and the satellite was lost. PSLV rockets remain grounded for inspection and testing after their recent failures, but the GSLV Mk 2 does not share PSLV's engines or major components, allowing this mission to proceed.

The same GSLV Mk 2 rocket recently carried the NASA-ISRO NISAR satellite, described as the world's most expensive Earth-observing satellite, into orbit. Narayanan said ISRO is planning seven rocket launches by March 2027, including Gaganyaan's first uncrewed G1 mission, as part of a target to build 12 satellites and launch eight rockets in the current financial year.