Why in News?

• India successfully launched the NASA–ISRO Synthetic Aperture Radar (NISAR) satellite aboard GSLV-F16 from Sriharikota on July 31, 2025

• It marks the first joint Earth observation mission between ISRO and NASA

  • Highlights deep Indo-US space collaboration

What is NISAR?

• Full Form – NASA–ISRO Synthetic Aperture Radar

• Nature – Joint Earth observation satellite using dual-frequency SAR technology

  • For monitoring land and ice

• Mission Life – 5 years (2025–2030)

  • With 12-day revisit cycles

• Orbit – Sun-synchronous polar orbit (747 km)

  • Ensures consistent lighting and accurate change detection

• Launch Site – Satish Dhawan Space Centre, Sriharikota

  • Aboard GSLV-F16

• First-ever polar orbit mission using GSLV

Objectives of the NISAR Mission

• Detect minute land and ice surface movements

  • With centimetre-level precision

• Monitor natural disasters

  • Earthquakes

  • Floods

  • Landslides

  • Volcanic activity

• Track environmental changes

  • Forests

  • Glaciers

  • Wetlands

  • Soil moisture

• Support key sectors with actionable data

  • Agriculture

  • Infrastructure

  • Coastal management

  • Climate management

Key Features of the NISAR Mission

• Dual-Frequency SAR

  • First satellite to use both L-band (NASA) and S-band (ISRO) radars

• Wide Swath & High Resolution

  • Scans 242 km swath

  • Provides detailed mapping every 12 days

• All-Weather, 24/7 Imaging

  • Operates day and night

  • Works through clouds and storms

• 12-metre Deployable Reflector Antenna

  • Enables advanced SweepSAR technology

  • Used for surface deformation detection

Contributions: India vs USA

• NASA

  • L-band radar

  • Deployable boom

  • Reflector antenna

  • GPS

  • Solid-state recorder

  • Telecom system

• ISRO

  • S-band radar

  • Satellite bus (I-3K)

  • GSLV-F16 launcher

  • Solar arrays

  • Data handling

  • Ground control

• Mission Management

  • Jointly executed via:

    • NASA’s JPL

    • ISRO’s centers: SAC, URSC, VSSC, NRSC

Significance of the NISAR Mission

• Scientific Edge

  • Provides global-scale, real-time Earth system monitoring

  • Helps in disaster forecasting

• Strategic Diplomacy

  • Strengthens Indo-US civil space cooperation

  • Promotes “science diplomacy”

• Climate Action & SDGs

  • Supports climate adaptation

  • Enables sustainable agriculture

  • Aids resource governance

• Knowledge Export

  • Open data policy

  • Benefits global researchers and developing nations in Earth sciences

Conclusion

• NISAR is a landmark in Indo-US space partnership

• Integrates advanced technology with societal benefits

• Shifts India from utility-driven to knowledge-led space applications

• Reinforces India’s leadership in Earth observation, sustainability, and global scientific cooperation