ISRO’s EOS-09 Mission Falters During Critical Third Stage

On the morning of May 18, 2025, India’s space agency, ISRO, saw its 101st mission hit a major snag. The Polar Satellite Launch Vehicle (PSLV-C61) lifted off as scheduled from the Satish Dhawan Space Centre in Sriharikota, carrying the advanced Earth observation satellite EOS-09 (also known as RISAT-1B). Despite a smooth ascent through the first two stages, fate intervened during the third.

A Sudden Glitch in the Third Stage

Telemetry data indicated a noticeable drop in chamber pressure approximately 203 seconds into the third-stage burn. The anomaly appeared within the flex nozzle mechanism—an essential component for steering the rocket during flight. As a result, the rocket veered off course, and the mission failed to place EOS-09 into its intended sun-synchronous orbit.

This marked just the third failure in the PSLV’s 63-flight history, with previous setbacks dating back to 1993 and 2017.

What Was EOS-09 Meant to Do?

EOS-09, carrying a C-band Synthetic Aperture Radar (SAR), was tailored for high-resolution imaging regardless of weather or daylight conditions. Its capabilities were expected to boost national surveillance, disaster response, border monitoring, and precision agriculture.

Had the launch succeeded, it would have joined a constellation of satellites ensuring seamless terrestrial monitoring across India.

ISRO’s Response and Forward Path

In the immediate aftermath, ISRO’s chair, V. Narayanan, announced the formation of a technical committee to dive deep into the cause of failure, particularly within the third stage. This body is tasked with reviewing manufacturing standards, test protocols, and operational data to avoid future mishaps.

Given ISRO’s proven track record of rapid recovery—often resuming missions within months—the organization is expected to bounce back with introspection and rigor.

Lessons from Failure and the Road Ahead

This setback is more than a launch failure—it’s a reminder of space exploration’s precarious nature. The complexity of rocketry, the razor-thin safety margins, and the weight of national ambitions all converge in these missions.

Yet, ISRO’s resiliency has always been its hallmark. With key projects like the NISAR satellite on the horizon, the agency’s ability to learn, adapt, and refocus remains critical for India’s expanding role in global space initiatives.

Even in failure, the journey illuminates the path ahead.