In a significant setback for India’s space programme, the Indian Space Research Organisation’s (ISRO) PSLV-C62 mission failed to place 16 satellites, including a foreign Earth Observation payload, into their intended orbit after an anomaly occurred in the critical third stage of the launch on Monday. The mission, which lifted off from the Satish Dhawan Space Centre in Sriharikota at 10:18 am IST, was expected to deploy a primary Earth Observation satellite along with multiple co-passenger satellites into a 512-kilometre Sun-Synchronous Orbit (SSO) over the course of a 17-minute flight. However, disturbances during the third stage led to a deviation from the flight path, ultimately resulting in the loss of all satellites aboard.

According to V Narayanan, chairman of ISRO, the rocket initially performed as expected during the first and second stages. “The PSLV is a four-stage vehicle with two solid stages and two liquid stages. The performance of the vehicle up to the end of the third stage was expected. Close to the end of the third stage, we observed disturbances in the vehicle, and subsequently, there was a deviation observed in the flight path,” he said in an address at the Mission Control Centre. The anomalies were particularly noticeable when the strap-on motors of the third stage were providing thrust to propel the vehicle to the intended altitude. This unexpected deviation during the critical phase meant that the satellite deployment sequence could not proceed as planned, and all payloads were effectively lost in space.

This failure marks the second consecutive PSLV mission to encounter an anomaly during the third stage. The previous mission, PSLV-C61-EOS-09, launched in May 2025, also faced failure due to a motor pressure issue, which involved a drop in the chamber pressure of the third-stage motor. The recurring issue with the third stage has prompted ISRO to initiate a detailed investigation to determine the exact cause of the failure and to implement corrective measures before resuming PSLV missions. A senior ISRO scientist, speaking to PTI on the condition of anonymity, stated that it would take time for the space agency to collect and analyse telemetry data, understand the precise sequence of events, and make the necessary adjustments for future missions.

The satellites lost in the PSLV-C62 mission include some of India’s most important strategic and developmental payloads. DRDO’s Anvesha, designed as a strategic super-eye to detect military camouflage from an altitude of nearly 500 kilometres, was among the primary Indian satellites on board. The mission also carried AayulSAT, India’s first in-orbit fuelling satellite, aimed at testing technologies for satellite refuelling in space, and CGUSAT, a small satellite developed by students primarily for emergency communication and disaster management applications. In addition to these Indian satellites, the PSLV-C62 carried an Earth Observation satellite developed jointly by Thailand and the United Kingdom, highlighting the international collaboration aspect of the mission. Another notable payload lost was the Kestrel Initial Technology Demonstrator (KID), a small-scale prototype of a re-entry vehicle from a Spanish startup. The loss of these satellites not only represents a setback for scientific and strategic projects but also affects international collaborations and student research initiatives dependent on the payloads.

The launch of PSLV-C62 had been preceded by a 22.5-hour countdown, which concluded successfully, and the rocket, standing 44.4 metres tall, lifted off as scheduled from the Sriharikota spaceport. The initial phases of the flight proceeded according to plan, with the rocket ascending through the atmosphere and staging events occurring as expected. However, the critical anomaly during the third stage disrupted the trajectory of the vehicle, preventing the fourth stage from performing its role in placing the satellites into the designated orbit.

The failure has significant implications for ISRO, which has relied on the PSLV (Polar Satellite Launch Vehicle) for decades as a reliable workhorse capable of deploying satellites into a variety of orbits. Known for its high success rate, the PSLV has been central to India’s space ambitions, including launching satellites for remote sensing, Earth observation, navigation, and scientific exploration, as well as carrying international payloads for commercial purposes. Consecutive failures, particularly in the third stage, raise questions about the reliability of the vehicle for future missions and may necessitate rigorous testing and redesign of the stage in question.

ISRO officials have emphasized that the space agency is fully committed to analysing the failure in detail. “A detailed investigation has been initiated to understand what went wrong, and ISRO will take the necessary steps to prevent recurrence,” said Narayanan. The investigation will involve a thorough review of telemetry data, mechanical and propulsion system performance, and the sequencing of operations during the third stage. The lessons learned from this analysis will be critical in ensuring the success of upcoming missions, including those planned for strategic, scientific, and commercial purposes.

The loss of payloads is also a setback for the organizations and nations that had invested in the mission. DRDO’s Anvesha, for example, was designed to enhance India’s surveillance and reconnaissance capabilities, particularly for detecting camouflage and other strategic military installations. Similarly, AayulSAT’s role in testing in-orbit satellite refuelling technology represented a significant step toward extending the operational life of spacecraft, which has broader implications for India’s capabilities in space logistics and satellite servicing. The loss of CGUSAT affects student projects that provide practical experience in satellite design, launch, and mission operations. The international payloads from Thailand, the United Kingdom, and Spain will also need to reassess their timelines and objectives in light of this unexpected outcome.

While the PSLV-C62 mission is a setback, ISRO has a strong track record of recovering from failures and implementing lessons learned. Historically, the agency has responded to anomalies with rigorous investigations, corrective engineering, and subsequent successful launches. Experts note that setbacks in space exploration, while costly, often provide invaluable insights that enhance the reliability and safety of future missions. The current failure, particularly the repeated anomaly in the third stage, will likely lead to renewed focus on quality assurance, stage testing, and pre-launch diagnostics to mitigate risks.

The incident also raises concerns regarding space debris, as the lost satellites and any rocket remnants now drift in Low Earth Orbit (LEO) without control. Space debris can pose collision risks to operational satellites, the International Space Station, and future missions in similar orbital regimes. ISRO, along with global space agencies, may need to monitor the debris to assess potential hazards and plan mitigation strategies.

In conclusion, the PSLV-C62 mission represents a stark reminder of the challenges inherent in space exploration. While ISRO has achieved numerous successes with the PSLV program over decades, the recent consecutive failures highlight the need for careful analysis, rigorous testing, and continued innovation to maintain reliability. The loss of 16 satellites, including strategic, scientific, student, and international payloads, is a significant setback for India’s space programme and its partners, but the agency’s established approach to problem-solving and learning from failures offers a pathway for recovery. The detailed findings from the ongoing investigation will shape the agency’s approach to future PSLV missions and help ensure that subsequent launches achieve their intended objectives, reinforcing India’s position as a reliable and capable player in space.

As ISRO continues its analysis and corrective measures, the space community and the public await the agency’s official report detailing the cause of the anomaly and the steps to prevent similar failures. Despite this setback, India’s space programme remains ambitious, with numerous planned missions in Earth observation, scientific exploration, defense, and commercial satellite launches, all of which underscore the importance of ensuring that each vehicle performs reliably to maintain the country’s position in the global space arena.