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#1
GalaxEye Space is an Indian private space-tech startup incubated at IIT Madras (founded in 2020 by Suyash Singh, Denil Chawda, Kishan Thakkar, Pranit Mehta, and Rakshit Bhatt) and headquartered in Bengaluru.
#2
Mission Drishti (weighing approximately 160 to 190 kg) is India’s largest privately built commercial satellite and the world’s first multi-sensor Earth Observation satellite integrating SAR and Optical payloads on a single platform.
#3
The core payload architecture of Mission Drishti is called SyncFused OptoSAR, which co-locates an active Synthetic Aperture Radar (SAR) and a passive Multispectral Optical Imaging (MSI) sensor on the same spacecraft bus.
#4
Passive Optical satellites rely on reflected sunlight in visible and near-infrared bands (), providing high spectral detail for chlorophyll and mineral mapping, but they cannot see through clouds, fog, smoke, or nighttime darkness.
#5
Active Synthetic Aperture Radar (SAR) satellites transmit their own microwave radio pulses (centimeter-scale wavelengths) and measure the backscattered echo, penetrating clouds, monsoon storms, and total darkness 24/7, but lack color/spectral band differentiation.
#6
Synthetic Aperture Radar (SAR) achieves fine spatial resolution without requiring a kilometer-wide physical dish by using the forward orbital motion of the satellite to synthesize a virtual antenna aperture hundreds of meters long via Doppler phase history processing.
#7
In tropical and monsoon regions such as India, cloud cover obscures the ground for nearly two-thirds of the year; GalaxEye’s OptoSAR data fusion uses synchronized SAR backscatter to reconstruct cloud-free, spectrally enriched Earth imagery regardless of weather.
#8
Historically, attempting to fuse images from a separate SAR satellite and a separate Optical satellite failed in dynamic environments (like moving ships or flash floods) because the two satellites pass over the target hours or days apart at different viewing angles.
#9
By mounting both sensors on the same satellite (Mission Drishti), GalaxEye achieves zero temporal lag (simultaneous acquisition) and identical orbital viewing geometry, eliminating cross-satellite co-registration errors.
#10
Mission Drishti is designed to operate in a Sun-Synchronous Low Earth Orbit (SSO) at an altitude of roughly 500 to 550 kilometers, achieving a spatial resolution down to 1.25 to 1.5 meters.
#11
A Sun-Synchronous Orbit (SSO) is a near-polar retrograde orbit (inclination ) whose orbital plane precesses eastward by roughly per day so the satellite crosses the equator at the exact same local solar time on every pass.
#12
Prior to building the full orbital satellite, GalaxEye tested its indigenous SAR drone payload on Unmanned Aerial Vehicles (UAVs) and successfully space-qualified its structural and electronics sub-systems aboard ISRO’s PSLV-C58 POEM-3 (PSLV Orbital Experimental Module-3) in January 2024.
#13
POEM (PSLV Orbital Experimental Module) is ISRO’s innovative platform that repurposes the spent fourth stage (PS4) of the PSLV rocket into an attitude-stabilized orbital laboratory powered by solar panels for Indian startups to test payloads in vacuum.
#14
GalaxEye executed formal Technical Assistance and test-facility agreements with IN-SPACe (Indian National Space Promotion and Authorisation Centre) under India’s Indian Space Policy 2023 to conduct environmental, thermovac, and vibration testing at ISRO facilities.
#15
In defense and strategic security, Mission Drishti detects "dark ships" (maritime vessels that illegally switch off their Automatic Identification System, AIS, transponders in the Indian Ocean Region) through cloud cover using SAR while identifying vessel signatures optically.
#16
In defense border monitoring along high-altitude Himalayan terrain, OptoSAR detects subtle vehicle tracks, camouflaged troop movements, and infrastructure changes even under winter snowstorms and dense fog.
#17
In agriculture and insurance, OptoSAR fusion tracks soil moisture levels, paddy transplantation acreage, and flood inundation depth during the Kharif monsoon season when traditional optical satellites are blinded by rain clouds.
#18
In aquaculture and coastal ecology, synchronized radar-optical datasets monitor prawn pond water quality, coastal erosion, mangrove deforestation, and offshore oil slicks.
#19
Following Mission Drishti, GalaxEye’s roadmap deploys a commercial constellation of 8 to 10 multisensor OptoSAR satellites in Low Earth Orbit to deliver sub-12-hour global revisit rates.
Subject Specialist Commentary
Analytical perspective & practical exam advice from the Master10 academic board
In UPSC Civil Services Prelims and GS Paper III (Science & Technology — Space Technology & Private Sector Participation under IN-SPACe), the GalaxEye Multisensor Satellite Project ('Mission Drishti') is a landmark current-affairs topic. Examiners love testing the exact physical contrast between Optical Remote Sensing (passive sensor, dependent on sunlight, blocked by clouds and night, rich spectral color signatures) and Synthetic Aperture Radar / SAR (active microwave sensor, independent of sunlight, penetrates clouds/smoke/rain 24/7, measures structural dielectric backscatter).
Aspirants should remember that IIT Madras-incubated GalaxEye Space solved this classic limitation by engineering the world's first single-satellite 'OptoSAR' sensor-fusion bus (Mission Drishti), capturing simultaneous, zero-time-lag SAR and Multispectral Optical imagery to provide all-weather maritime surveillance across the Indian Ocean and monsoon-proof agricultural crop monitoring.
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