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India remote sensing


1. Foundational Phase (Early 1970s – Early 1980s)

Objective: To explore the potential of space-based observation for national development.

  • 1972: The Space Applications Programme (SAP) was initiated by the Indian Space Research Organisation (ISRO), focusing on applying space technology for societal benefits.

  • 1975: The Department of Space (DoS) was established, providing an institutional base for space applications, including remote sensing.

  • 1977: India began aerial and balloon-borne experiments to study Earth resources and assess how remote sensing data could aid in agriculture, forestry, and hydrology.

  • 1978 (June 7): Bhaskara-I launched by the Soviet Union — India's first experimental Earth Observation satellite.

    • Payloads: TV cameras (for land and ocean surface observation) and a Microwave Radiometer.

    • Significance: Proved that satellite-based Earth observation was feasible for India's needs.

  • 1981 (November 20): Bhaskara-II launched.

    • Improvements: Enhanced radiometric and optical sensors for land use, forestry, and hydrology.

    • Outcome: Successful demonstration of indigenous data analysis and interpretation.

2. Institutional Strengthening and User Involvement (1980–1985)

Objective: To integrate remote sensing into national planning.

  • 1980: Aryabhata, India's first satellite (for science/technology), laid the foundation for satellite engineering.

  • 1983: Formation of the National Natural Resources Management System (NNRMS).

    • Purpose: Coordinate and integrate the use of remote sensing data with conventional data for national resource management.

    • Structure: Involved multiple user ministries (agriculture, water, forestry, etc.) and established Regional Remote Sensing Service Centres (RRSSCs).

    • Impact: Shift from experimental use to operational planning.

  • 1984: India began receiving data from LANDSAT and NOAA satellites through its own ground station in Shadnagar, Hyderabad — enhancing domestic data processing capabilities.

3. First-Generation Operational Satellites (1988–1995)

Objective: To launch and operate India's own Earth observation satellites.

  • 1988 (March 17): IRS-1A launched by the Soviet Union's Vostok launcher from Baikonur Cosmodrome.

    • Payload: LISS-I (72.5 m) and LISS-II (36.25 m) multispectral sensors.

    • Orbit: Sun-synchronous polar orbit.

    • Applications: Agriculture, forestry, water resource mapping, and soil studies.

    • Significance: Marked the beginning of the Indian Remote Sensing (IRS) series — India's first operational remote sensing satellite.

  • 1991 (August 29): IRS-1B launched — a near-identical successor with improved calibration and longer life.

    • Outcome: Data from IRS-1A/1B validated the national system for operational resource monitoring.

    • Impact: India achieved self-reliance in Earth observation for key resource sectors.

4. Second-Generation IRS Satellites (1995–2000)

Objective: To enhance spatial resolution and expand thematic applications.

  • 1995 (December 28): IRS-1C launched (from Baikonur).

    • Sensors:

      • PAN (5.8 m),

      • LISS-III (23.5 m),

      • WiFS (188 m).

    • Applications: Cartography, urban planning, and vegetation monitoring.

    • Significance: India entered the high-resolution mapping era.

  • 1997 (September 29): IRS-1D launched — similar to IRS-1C, providing stereo coverage and better radiometric accuracy.

  • 1998: Data from IRS-1C/1D began supporting international users, establishing India as a global remote sensing data provider.

5. Diversification and Specialized Missions (1999–2010)

Objective: To develop satellites tailored for thematic domains — oceans, cartography, and natural resources.

  • 1999 (May 26): IRS-P4 (Oceansat-1) launched.

    • Payload: Ocean Colour Monitor (OCM) and Multi-frequency Scanning Microwave Radiometer (MSMR).

    • Use: Ocean productivity, fisheries, and climate studies.

  • 2001 (May 5): IRS-P6 (Resourcesat-1) launched.

    • Sensors: LISS-III, LISS-IV, and AWiFS.

    • Purpose: Detailed agricultural and natural resource management.

  • 2005 (May 5): IRS-P5 (Cartosat-1) launched.

    • Payload: Two panchromatic cameras providing 2.5 m stereo imagery.

    • Applications: High-resolution cartography and digital elevation models (DEMs).

  • 2007 (October 23): Cartosat-2 launched — sub-meter resolution imagery.

    • Use: Urban planning, infrastructure, and defense.

  • 2009 (September 23): Oceansat-2 launched — followed by the Megha-Tropiques and SARAL (joint missions for climate and ocean studies).

6. Modernization and Microwave Era (2011–Present)

Objective: Integration of optical and microwave sensors, enhanced revisit times, and global data distribution.

  • 2013 (April 28): Resourcesat-2 launched — continuation of Resourcesat-1 with improved radiometry.

  • 2016 (March 10): Cartosat-2C launched — 0.65 m resolution; supported Smart City and infrastructure projects.

  • 2018 (March 12): Cartosat-2F launched, maintaining high-resolution optical imaging continuity.

  • 2019 (December 11): RISAT-2BR1 launched — radar imaging satellite with all-weather day-night capability.

    • Microwave sensors: Enabled mapping even under cloud cover, marking India's operational SAR (Synthetic Aperture Radar) era.

  • 2020–2023:

    • Launch of EOS (Earth Observation Satellite) series — replacing IRS nomenclature.

    • Satellites: EOS-01 (RISAT-type), EOS-04 (Radar), EOS-06 (Oceansat-3).

    • Integration of optical, microwave, and hyperspectral imaging systems.

7. Current Framework and Data Access (2020s–Present)

Objective: Streamline commercial and data dissemination processes.

  • 2020: Formation of NewSpace India Limited (NSIL) — a commercial arm of ISRO, responsible for marketing remote sensing data globally.

  • 2021: Launch of Bhoonidhi (Bhuvan-NIDHI) — ISRO's centralized data dissemination platform.

    • Provides access to IRS and EOS datasets for research, academia, and government users.

  • 2023–2025:

    • Integration with Digital India and Gati Shakti initiatives.

    • IRS data now forms the backbone of India's resource management, agriculture monitoring, climate resilience, and disaster response.

    • Over 15 active IRS/EOS satellites, making it the largest civilian remote sensing constellation globally.


PhaseYearsKey SatellitesMajor Achievements
Experimental1978–1981Bhaskara I & IIFirst Earth observation experiments
Institutionalization1983–1987NNRMS setupIntegration of users and ministries
First Generation1988–1991IRS-1A, 1BOperational remote sensing begins
Second Generation1995–2000IRS-1C, 1DHigh-resolution multispectral imaging
Specialized Missions1999–2010Oceansat, Cartosat, ResourcesatThematic data for various domains
Microwave & Modern Era2011–PresentRISAT, EOS seriesAll-weather, day-night, multi-sensor observation


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