The back-to-back failures of the PSLV-C61 mission in May 2024 and the PSLV-C62 mission today (January 12, 2026) are significant setbacks to India’s space-based military capabilities.
Worryingly, both missions failed for similar reasons—anomalies in the performance of the PSLV third stage (PS3).
The PSLV-C61 failure resulted in the loss of EOS-9 (also known as RISAT-1A), while the PSLV-C62 failure led to the loss of the EOS-N1 (Anvesha) satellite. Both were primarily military satellites.
RISAT-1A was a radar imaging satellite capable of imaging the Earth’s surface day or night, and through all weather conditions.
The Anvesha satellite (EOS-N1) was a hyperspectral imaging Earth-observation platform developed by India’s Defence Research and Development Organisation (DRDO).
Earth Observation Satellite Imaging
Earth-observation satellite imaging may be confined to the visual spectrum, in which case sensors capture imagery either in black-and-white (panchromatic) or in full colour.
Alternatively, imaging can extend beyond the visual spectrum using multispectral or hyperspectral sensors.
Multispectral Imaging
Multispectral satellites capture images in a limited number (typically 3–10) of discrete spectral bands, each about 50–500 nm wide.
ISRO has previously launched several multispectral satellites under the IRS series, supporting applications such as agriculture, forestry, water resources management, and urban planning.
Multispectral imaging resolutions typically range from 10–30 metres per pixel.
Hyperspectral Imaging
Hyperspectral satellites capture imagery across hundreds of narrow, contiguous spectral bands—typically 5–20 nm wide—providing a near-continuous spectrum for every pixel.
ISRO has previously launched and operated a hyperspectral satellite: the Hyperspectral Imaging Satellite (HySIS), weighing 380 kg, launched aboard PSLV-C43 on November 29, 2018. The 400-kg Anvesha (EOS-N1) satellite was developed by DRDO in collaboration with ISRO.
Hyperspectral imaging resolution is lower than multispectral imaging, typically in the range of 30–100 metres per pixel.
Military Imaging Reconnaissance
Most military imaging reconnaissance satellites rely on panchromatic (black-and-white) imaging, with effectiveness judged primarily by image resolution. Panchromatic imaging enables very high spatial resolution, measured in centimetres rather than metres.
For example, U.S. Keyhole-series satellites (e.g., KH-11) and their modern equivalents reportedly achieve resolutions of 15 cm or better.
Military Advantages of Hyperspectral Imaging
From the point of view of the military, high-resolution panchromatic satellites are essential for accurate targeting and precise geolocation while hyperspectral imaging (HySI) is primarily aimed at situational awareness.
Panchromatic imagery can identify the precise coordinates of a parked fighter aircraft to enable a missile strike. HySI, however, can determine whether the observed object is an actual aircraft or a decoy—often with close to 90% accuracy—by analysing the unique spectral signatures of constituent materials.
By capturing data across hundreds of narrow wavelength bands, HySI enables precise identification of surface compositions such as metals, composites, paints, and synthetic materials like plastics or inflatables commonly used in decoys.
Such material discrimination is not possible using panchromatic or multispectral imaging.
Beyond decoy identification, hyperspectral imaging offers several unique military reconnaissance capabilities:
Missile Launch Detection and Early Warning
HySI can detect ballistic missile launches by identifying and analysing their infrared signatures immediately after launch, enabling early warning and cueing radar sensors for tracking.
Camouflage Penetration
HySI can penetrate camouflage—such as vegetation, netting, or paint—by analysing subtle spectral differences. It can distinguish natural foliage from synthetic coverings used on vehicles, bunkers, or troop positions, aiding in the detection of concealed assets like missile launch sites.
Detection of Buried or Obscured Threats
HySI can detect buried objects such as landmines, improvised explosive devices (IEDs), and unexploded ordnance (UXOs) by identifying soil disturbances and anomalous material signatures.
By effectively “seeing” a minefield, HySI can help ground forces clear routes safely, reducing uncertainty in mission planning.
Asset Maintenance and Corrosion Detection
For military hardware such as aircraft and naval vessels, hyperspectral sensors can identify early signs of corrosion or metal fatigue through spectral analysis, enabling proactive maintenance and reducing downtime and lifecycle costs.
Conclusion
Through consecutive PSLV mission failures, India has lost critical, sovereign military space capabilities that cannot be sourced from abroad. The restoration of the all-weather radar imaging capability lost with RISAT-1A, and the reconstitution of the hyperspectral imaging (HySI) capability lost with Anvesha, could take up to two years or more. This gap carries real operational consequences, weakening India’s independent ISR posture at a time when timely, high-fidelity space-based intelligence is increasingly central to deterrence and warfighting.
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