
Explainer: Why ISRO's PSLV Mission With EOS-9 Satellite Failed And What It Means
The mission took off at 5:59 am from the Satish Dhawan Space Centre in Sriharikota. Initial signs were promising. The rocket cleared the first and second stages of flight successfully – the early benchmarks of any PSLV launch. However, it was during the third stage that a sudden drop in chamber pressure led to an anomaly, effectively ending the mission before the satellite could be placed into its intended orbit.
The third stage of the PSLV uses a solid rocket motor, which provides high thrust once the vehicle has exited the dense layers of the atmosphere. In this flight, although ignition occurred as expected, sensors recorded a drop in pressure within the chamber – indicating a failure in the propulsion process.
ISRO Chairman V. Narayanan confirmed the technical anomaly and stated that a detailed analysis was already underway.
This launch was significant as the PSLV has been a workhorse for ISRO – known for its reliability, having successfully delivered missions like Chandrayaan-1 and Mangalyaan. The failure marks a rare blemish in its otherwise solid track record. It was also ISRO's 101st mission from Sriharikota.
Now, both an internal Failure Analysis Committee and an external government-appointed review body are expected to investigate the root cause. These panels typically deliver a comprehensive assessment within weeks, which then guides corrective action for future missions.
The payload – Earth Observation Satellite 9 (EOS-9) – was designed for continuous surveillance, including border monitoring, disaster response, urban planning and agricultural management. Of particular importance was its Synthetic Aperture Radar (SAR), enabling day-and-night, all-weather imaging – a key asset for national security and civil planning.
The failed deployment of EOS-9 means a temporary gap in ISRO's remote sensing capabilities. While other satellites, such as Cartosats and radar platforms, remain operational, the unique capabilities of EOS-9 will now be missed. Its replacement, once commissioned, could take years to be developed and launched.
The mission had also integrated space sustainability into its design. EOS-9 was equipped with extra fuel to perform a planned de-orbit maneuver at the end of its lifecycle, ensuring it would not contribute to space debris – a growing global concern.
Despite the setback, ISRO's long-term record and response mechanisms reflect a strong system built on transparency and technical rigor.
Hashtags

Try Our AI Features
Explore what Daily8 AI can do for you:
Comments
No comments yet...
Related Articles


India.com
an hour ago
- India.com
Big tension for Trump, Putin as China successfully tests hypersonic missile Feitian-2,' it uses atmospheric oxygen for..., is developed by...
As conflicts continue to erupt around the world, every country boosts its defense readiness for the greater threats that are imminent. Every country is arming itself with modern warfare capabilities and advanced weapons to maintain a military advantage in a world where national security is getting increasingly volatile. In what may be a significant breakthrough for hypersonic technology, China has successfully demonstrated a test flight of its Feitian-2 hypersonic vehicle in northwestern China, where it was able to switch between different propulsion modalities in flight — a significant hurdle in the future development of hypersonic vehicles. Who developed the Feitian-2 hypersonic vehicle? The Feitian-2 hypersonic vehicle was developed as a part of the cooperation between Northwestern Polytechnical University (NPU) and the Shaanxi Province Aerospace and Astronautics Propulsion Research Institute, as reported by the Economic Times. The flight is consistent with the advancements made by Feitian-1 when it successfully flew in July 2022 and demonstrates useful data for many physical understandings rich in applications regarding Rocket-Based Combined Cycle (RBCC) engine technology. The flight offers performance parameters that form a useful physical basis for future engineering research on aerodynamics and high-speed propulsion. Top features of Feitian-2 that make it stand out! How atmospheric oxygen helps Feitian-2 The standout feature of Feitian-2 is its Rocket-Based Combined Cycle (RBCC) engine operating on a kerosene and hydrogen peroxide combination. In contrast to traditional hypersonic vehicles, which are fueled by cryogenic fuels such as liquid oxygen, the Feitian-2 craft incorporates atmospheric oxygen for portions of the flight. The use of atmospheric oxygen reduces onboard oxidizers, enhancing fuel efficiency. Feitian-2 different modes The flight experiment with Feitian-2 successfully showed a seamless switch from the first ejector mode, where rockets provide thrust for take-off, to ramjet mode (air-breathing propulsion). This smooth mode switch will be a significant benchmark for sustained hypersonic flight. The engine also showed its variable-geometry intake capability, demonstrating the ability for flow to be controlled automatically in real time. The control of airflow in real-time means that performance can be improved with speed and altitude. This central dynamic feature makes the engine more reliable and the system more efficient with complex flight profiles. How are Feitian-1 and Feitian-2 different? Feitian-2 has several additions as compared to its predecessor, Feitian-1. It features larger tail fins, and new wings just in front of the rocket's nose, improving the stability and maneuverability during high-speed high-altitude flight. Overall, the upgrades will allow for greater aerodynamic control and flight accuracy in more extreme conditions. This test also verified that Feitian-2 can fly autonomously. It was able to alter its angle of attack during flight based on the needs of the mission and the conditions around it. This ability is going to be very important for future unmanned hypersonic systems for both military and scientific missions. Feitian-2 is powered by a kerosene-hydrogen peroxide mixture instead of the traditional cryogenic fuels. While kerosene has less energy even than liquid hydrogen, it is much simpler to store and handle, which leads to a simpler vehicle layout and overcomes the need for heavy cooling systems. Meanwhile, Feitian-1 had previously demonstrated the use of kerosene in hypersonic engines. Moreover, Feitian-2 uses hydrogen peroxide, which is a liquid oxidizer, improving the overall weight of the vehicle while providing stable thrust. This fuel combination may be a factor in the design and operation of hypersonic vehicles in the future. China's recent advances in hypersonic technology are likely causing the US some concern. Although both America and Russia have been trying to develop combined-cycle engines for years, they have had little success. The Feitian-2 testing shows that China is making significant gains in gathering real, valuable data for hypersonic engine design, and they are showing progress in a difficult area that can bring real challenges. The Feitian-2 test flight has elevated China to a competitive status in the world hypersonic technology race by demonstrating its ability to switch between propulsion modes in flight and with an autonomous control structure while actively managing airflow. These advances may have potential uses besides defense, including fast transportation uses and civilian rapid-response systems.


Time of India
2 hours ago
- Time of India
Top 10 nations with the most satellites in space
Image: iStock Earth's orbit is more crowded than ever in 2025. According to Orbiting Now, nearly 12,952 satellites are currently orbiting our planet. So far this year alone, 145 new satellites have been launched into space. These satellites serve a variety of purposes, from communications and navigation to military surveillance and scientific research. They are typically deployed into geostationary (GEO), medium Earth (MEO), or low Earth orbits (LEO), with small satellites dominating LEO and larger ones occupying GEO and MEO positions. Satellites are now registered by 105 countries or multinational organizations, marking a steep rise in global participation in space. Top 10 countries with the highest number of satellites in 2025 1. United States – 8,530 Satellites The United States leads the satellite race by a huge margin, with 8,530 satellites currently in orbit. This includes contributions from government agencies like NASA and the Department of Defense, alongside major commercial players. SpaceX, in particular, boosted this number with its Starlink project, which alone accounts for over 7,400 satellites offering global internet services. Other major U.S. companies such as Amazon's Project Kuiper and Iridium are also expanding rapidly. by Taboola by Taboola Sponsored Links Sponsored Links Promoted Links Promoted Links You May Like These Are The Most Beautiful Women In The World Undo 2. Russia – 1,559 Satellites Russia maintains a powerful satellite presence, with 1,559 satellites orbiting Earth. The Roscosmos State Space Corporation has announced plans to grow its constellation to 2,600 satellites by 2036, with 35% expected to be commercial. Russia's satellites focus heavily on remote sensing, communication, and defense systems. It also remains committed to expanding its navigation system, GLONASS, as a counterbalance to the U.S. GPS network. 3. China – 906 Satellites China has a robust and fast-growing satellite fleet of 906 satellites, covering military, governmental, and commercial use. In 2025, China launched multiple missions, including CERES-1, Guowang broadband constellation launches, and Long March 6A missions. The country's efforts are centralized under the China National Space Administration (CNSA), but also include contributions from private players like iSpace and GalaxySpace. China also plans to rival Starlink through its massive Guowang mega-constellation. 4. United Kingdom – 763 Satellites The UK currently has 763 satellites in orbit as of March 2025, as confirmed by data from the UK Parliament. These serve purposes in military ISR (intelligence, surveillance, reconnaissance), scientific research, communications, and technology demonstrations. The UK's growing role in space is also supported by private companies like OneWeb, which plans to expand its broadband satellite network globally. 5. Japan – 203 Satellites Japan's satellite infrastructure includes 203 active satellites, which span scientific, governmental, military, and commercial applications. A significant part of Japan's efforts is focused on navigation systems, with 5 QZSS (Quasi-Zenith Satellite System) satellites already operational and plans to expand to 7 satellites by March 2026. The Japan Aerospace Exploration Agency (JAXA) continues to lead ambitious space science missions while expanding defense-related capabilities. 6. France – Over 100 Satellites France has a fleet of more than 100 satellites used for military intelligence, Earth observation, and space defense demonstrations. As a leading space player in Europe, France continues to build sovereign capability with satellite projects like CO3D (a constellation for 3D Earth observation) and YODA (a military space surveillance system). France collaborates closely with the European Space Agency (ESA) but also leads independent launches through Arianespace. 7. India – 136 Satellites India, through the Indian Space Research Organisation (ISRO), operates 136 satellites, including contributions from academic institutions and private companies. India's operational fleet includes 22 satellites in LEO, 32 in GEO, and key interplanetary missions like Chandrayaan-2's orbiter and the Aditya-L1 solar mission. According to ISRO Chairman V. Narayanan, India plans to launch 100–150 additional satellites over the next three years to enhance security, climate monitoring, and digital connectivity. 8. Germany – 82 Satellites Germany has 82 satellites in space , used for governmental, defense, scientific, and commercial purposes. It is now working to significantly bolster its military space infrastructure, with the Bundeswehr aiming to deploy its own satellite constellation by 2029. German companies like OHB SE and Airbus Defence and Space are also pushing innovation in both national and European collaborative missions. 9. Italy – 66 Satellites Italy currently operates 66 satellites, primarily used for communications, Earth observation, and navigation. The country's IRIDE constellation, comprising 34 satellites, is central to its domestic space goals. Additionally, a proposed National Constellation, which could bring the total to around 100 satellites by 2030, is aimed at supporting climate observation and national security needs. 10. Canada – 64 Satellites Canada rounds off the top 10 with 64 satellites. Its space efforts focus on Earth observation, climate research, communications, and scientific exploration. Major Canadian firms like Telesat, MDA, and GHGSat lead satellite missions, while international collaboration allows Canada to participate in deep space and human exploration programs through partnerships with NASA and others. As humanity's need for connectivity, defense, navigation, and climate intelligence continues to expand, so does our presence in space. While the United States leads by a massive margin, emerging space powers like India, the UK, and China are rapidly closing gaps. The sky is no longer the limit — it's a crowded, competitive, and collaborative frontier.


Time of India
3 hours ago
- Time of India
Axiom-4 one small step in orbit, giant leap for spaceflight & discovery: Isro
BENGALURU: Several days after India's Group Captain Shubhanshu Shukla entered the International Space Station (ISS), , stating that 'space is a domain best explored together,' said its participation in the Axiom-04 mission echoes that spirit. Tired of too many ads? go ad free now Axiom-4 follows in the legacy of international cooperation that sent Rakesh Sharma to space in 1984 aboard the Soviet Soyuz, Isro said, and added: '...This is one small step in orbit, but a giant leap in India's pursuit of human spaceflight and scientific discovery.' The space agency said: '...The professionalism, dedication, and scientific excellence demonstrated by all partner agencies in the lead-up to the Axiom-4 mission have been truly inspiring. Isro is deeply appreciative of the partnership and camaraderie shown by our counterparts around the world.' Reiterating that the mission was conceptualised during PM Narendra Modi's visit to the US in 2023, Isro said the PM's leadership continues to shape India's future in space as one that is collaborative, confident, and committed to peaceful exploration. Ax-4 is expected to provide useful operational inputs for Isro's , particularly in areas such as astronaut health telemetry, crew-ground coordination, multi-agency integration, and experiment execution in space conditions. 'These insights will directly influence mission planning, safety validation, and astronaut readiness for India's first indigenous human spaceflight mission,' Isro said. Onboard the ISS, a set of Indian scientific experiments is being conducted as part of the Ax-04 mission. These cover life sciences, fluid dynamics, health monitoring, and Earth observation. 'Redwire Space, US, is coordinating the payload integration activities. Tired of too many ads? go ad free now Redwire facilitated key steps, including technical validation and compliance with ISS payload requirements. Each experiment is packaged into flight-ready payload containers. Redwire is also supporting the development of hardware handling protocols, ensuring that the Indian experiments could be safely deployed and operated onboard ISS, thereby enabling meaningful scientific outcomes for India's research community,' Isro said. Pointing out how the launch was rescheduled multiple times due to issues such as a harness problem in Dragon, weather in the ascent corridor, leakage in the Falcon-9 booster stage, and leakage in the Zvezda Module of the ISS, the space agency said: 'The Isro delegation played a constructive role in resolving all the issues. It made its stand clear that all problems should be resolved before clearing the launch for lift-off, considering the mission risks and safety of the crew. ' The Indian astronauts —Shukla and his backup Group Captain Prashanth B Nair — have trained in spacecraft systems, microgravity operations, emergency protocols, space medicine, and experiment handling. As part of the programme, he also participated in Nasa's National Outdoor Leadership Programme (NOLPS) in the Mexican wilderness, designed to build team resilience and psychological readiness.