The India Space Research Organisation (ISRO) launched its 101st satellite, EOS-O9, on Sunday aboard the PSLV-C61 from the Satish Space Centre in Sriharikota, but was not able to complete the mission as it failed to place its Earth observation satellite EOS-09, into orbit. The satellite experienced an unexpected issue during the third stage of the PSLV-C61 rocket, ISRO Chairman V Narayanan confirmed the setback. He mentioned that the initial phase of the launch was initiated normally, but the mission could not be fulfilled later.
Today 101st launch was attempted, PSLV-C61 performance was normal till 2nd stage. Due to an observation in 3rd stage, the mission could not be accomplished.
— ISRO (@isro) May 18, 2025
Why SRO’s 101st mission failed?
ISRO Chief explained the technical issue that resulted in the failure of the PSLV-C61 mission, stating that the third stage of the launch vehicle faced an unexpected anomaly.
”We attempted the launch of the PSLV-C61 today. The vehicle consisted of four stages. While the first and second stages functioned normally, we encountered a problem during the third stage,” Narayanan stated in a statement.
He further clarified that the third stage, equipped with a solid propellant motor, recorded a drop in the chamber pressure during the flight, which finally caused the mission to fail.
The chairman gave assurance that the ISRO teams are thoroughly examining the data to find out the exact reason of the mission failure. ”We are reviewing the complete flight performance and will provide updates as soon as the analysis is complete,” he added.
”The PSLV-C61 was intended to mark ISRO’s 101st launch from Sriharikota. The vehicle’s first and second stages operated as expected.” Narayanan stated during a press briefing. ”However, although the third stage motor ignited correctly, an anomaly was observed during its operation. Due to this, the mission was not completed as planned.”
All about EOS-09 satellite
EOS-09 is an advanced Earth Observation Satellite designed for capturing high-resolution images using C-band synthetic aperture radar. It has potential for giving inputs on all-weather, day and night imaging, which are important for disaster response, agriculture and forestry, and border surveillance.
The satellite was made in a way to function in a Sun Synchronous Polar Orbit (SSPO) for ensuring constant observation conditions. The satellite was designed in line with ISRO’s commitment to sustainable space operations. ISRO’s EOS-09 was equipped with deorbiting fuel and offered safe disposal post-mission. As per the plan, after the satellite was deployed, in PSLV’s fourth stage, the Orbit Change Thrusters were to be lowered and then passivated to reduce space debris risk.