ISRO’s PSLV-C61/EOS-09 Mission Faces Setback Due to Stage-3 Glitch

In a rare setback, the Indian Space Research Organisation (ISRO) was unable to accomplish its 101st mission involving the PSLV-C61 launch carrying the EOS-09 earth observation satellite. The mission, launched from the Satish Dhawan Space Centre on May 18, 2025, failed due to an unexpected issue in the third stage of the PSLV rocket.

Why in News?

The PSLV-C61/EOS-09 mission, aimed at deploying a critical Earth observation satellite into a Sun Synchronous Polar Orbit (SSPO), could not be completed. A fall in chamber pressure during the third stage of the rocket led to mission failure, marking a significant anomaly in ISRO’s otherwise strong PSLV track record.

Background & Mission Overview

• Launch Date: May 18, 2025, 5:59 a.m. IST
• Launch Site: Satish Dhawan Space Centre, Sriharikota
• Mission Name: PSLV-C61/EOS-09
• Satellite Weight: 1,696.24 kg
• Configuration: PSLV-XL (Extra Large)

Objectives of EOS-09

• To provide all-weather earth observation through Synthetic Aperture Radar (SAR).
• To supply continuous remote sensing data for operational applications in agriculture, forestry, soil moisture, disaster management, etc.
• Enhance frequency and reliability of remote sensing outputs.

Technical Glitch

• The first and second stages performed nominally.
• Third stage anomaly: Fall in chamber pressure in the solid rocket motor.
• Result: The mission could not place EOS-09 into the intended orbit.

PSLV-C61 in Context

• 101st ISRO mission, 63rd flight of PSLV.
• Only third failure since the PSLV’s first flight in 1993.
• Last failure before this: PSLV-C39 in 2017.
• Previous successful mission: SpaDeX (Dec 2024)

EOS-09 Satellite

• Uses RISAT-1 heritage bus, developed for all-weather radar imaging.
• Mission Life: 5 years
• Equipped with SAR payload to capture high-resolution images in all weather.

ISRO Response

• ISRO Chairman V. Narayanan confirmed technical failure and assured post-mission analysis.
• Former Chairman S. Somanath expressed confidence in ISRO’s capacity to identify and correct the fault.

Recent Setbacks

• Follows the NVS-02 mission anomaly in Jan 2025 due to a valve malfunction.
• Reflects the increasing complexity of India’s space missions and the need for evolving technology validation.

Summary/Static	Details
Why in the news?	ISRO’s PSLV-C61/EOS-09 Mission Faces Setback Due to Stage-3 Glitch
Mission Name	PSLV-C61/EOS-09
Launch Date	May 18, 2025
Mission Status	Unsuccessful due to third-stage failure
Satellite Objective	Earth observation using Synthetic Aperture Radar
Satellite Weight	1,696.24 kg
PSLV Flight Number	63rd PSLV mission, 27th in XL configuration
ISRO Response	Investigation underway into third-stage anomaly
Previous PSLV Failure	PSLV-C39 in 2017