The Indian Space Research Organisation (ISRO) faced a major setback on May 18, 2025, with its 101st satellite mission. The launch, conducted from the Satish Dhawan Space Centre in Sriharikota, involved the Polar Satellite Launch Vehicle (PSLV-C61) carrying the advanced Earth Observation Satellite EOS-09.
The mission was intended to place EOS-09 into a Sun Synchronous Polar Orbit (SSPO), enhancing India's capabilities in earth observation, agriculture, forestry, disaster management, and strategic surveillance through its C-band Synthetic Aperture Radar (SAR) technology.
The PSLV-C61 rocket, standing 44.5 meters tall and weighing 321 tonnes at lift-off, took off at 5:59 am IST. Initial phases of the mission proceeded smoothly, with the first and second stages performing as expected. However, during the critical third stage of flight, an anomaly occurred. ISRO Chairman V Narayanan confirmed that while the third stage motor started perfectly, a sudden fall in chamber pressure was observed in the motor case. This technical glitch prevented the satellite from reaching its intended orbit, resulting in the mission's failure.
EOS-09, weighing 1,696.24 kg, was designed as a follow-up to the earlier EOS-04 satellite, aiming to improve the frequency and continuity of high-resolution earth observation data for operational users. The satellite's SAR payload was capable of capturing images under all weather conditions, day and night, making it a vital asset for various applications, including national security and resource management.
This mission marked the 63rd flight of the PSLV and the 27th using its XL configuration, known for accommodating heavier payloads. It was also notable for its commitment to responsible space operations, as EOS-09 was equipped with deorbiting fuel to ensure safe disposal after its operational life.
The failure of PSLV-C61/EOS-09 is only the third in the PSLV series' long history, highlighting the generally reliable performance of this launch vehicle. ISRO has announced that a detailed analysis will be conducted to determine the exact cause of the anomaly in the third stage, and the agency has assured that it will return with further findings after the investigation.
The mission's failure was a disappointment for many, including families and students who had travelled to witness the launch, only to be turned away due to heightened security concerns amid regional tensions. Despite the setback, there remains widespread support and pride in ISRO's achievements and ongoing efforts in advancing India's space capabilities.
Agencies