PSLV-C61 launch countdown begins: Check all details on ISRO's EOS-09 Satellite Mission

The Indian Space Research Organisation (ISRO) has officially begun the 22-hour countdown for its upcoming PSLV-C61 mission, which is scheduled to launch at 5:59 am on May 18, 2025, from the Satish Dhawan Space Centre in Sriharikota, Andhra Pradesh. The countdown began at 7:59 am on May 17, marking the final phase of preparation for what will be the 63rd flight of the Polar Satellite Launch Vehicle (PSLV) and ISRO’s 101st mission overall.

What is EOS-09 (RISAT-1B)?

The PSLV-C61 rocket will carry EOS-09 (also known as RISAT-1B), a next-generation Earth Observation Satellite weighing around 1,696 kilograms. The satellite is designed to provide high-resolution, all-weather imaging of the Earth’s surface, which is crucial for a wide range of applications including agriculture, forestry, disaster management, urban planning, and national security. Once deployed, EOS-09 will join India’s growing fleet of Earth observation satellites such as Resourcesat, Cartosat, and RISAT-2B, significantly enhancing the country’s remote sensing capabilities.

Launch plan

The PSLV-C61 will complete its mission in approximately 17 minutes, placing the satellite into a Sun Synchronous Polar Orbit (SSPO). After separation, Orbit Change Thrusters (OCTs) will be used to make fine adjustments to the satellite’s orbit. The mission life of EOS-09 is expected to be five years, but ISRO has also planned a controlled de-orbiting process to ensure the satellite burns up safely in Earth’s atmosphere after its operational life, reducing space debris and supporting sustainable space practices.

Mission life

According to ISRO, the EOS-09 satellite is a repeat of the EOS-04 mission launched in 2022 and acts as a follow-on to RISAT-1. Though the satellite was developed before the current year, its capabilities are being seen as a strategic asset in India's space-based Earth monitoring initiatives. The satellite will provide real-time, round-the-clock imaging, making it a vital tool for government agencies and researchers alike.

As anticipation builds for the launch, ISRO has urged viewers to follow official channels for live coverage, images, and updates. With EOS-09, India is poised to take another major step forward in its space-based Earth observation and remote sensing programme.

With inputs from PTI