NISAR Mission
NISAR(NASA-ISRO Synthetic Aperture Radar)is a joint Earth-observing satellite mission developed by the National Aeronautics and Space Administration(NASA)and theIndian Space Research Organisation(ISRO). It is scheduled to launch inJune 2025.
Its aim is to measure changes in terrestrial ecosystems, ice sheets, glaciers, sea ice, and crust deformation.
Background & Collaboration
The partnership between NASA and ISRO for the NISAR mission was formalized onSeptember 30, 2014. As part of this collaboration:
- NASAprovides theL-band radar, high-rate communication subsystem, GPS receivers, and a payload data subsystem.
- ISROcontributes to theS-band radar, satellite bus, and launch services.
The satellite will be launched aboard ISRO’sGeosynchronous Satellite Launch Vehicle Mark II(GSLV Mk II) from theSatish Dhawan Space Centre, Sriharikota.
Key Technologies & Applications
NISAR will be thefirst satellite mission to operate dual-frequency radar systems, using:
- L-band radar (by NASA)
- S-band radar (by ISRO)
It will be the first satellite mission to collect radar data in two microwave bandwidth regions, allowing it to observe a wide range of Earth processes.
NISAR employs a sophisticatedSynthetic Aperture Radar (SAR)technique.
SAR can generate high-resolution images of the Earth's surface regardless of weather conditions or time of day. Its 'SweepSAR' technology allows for a large coverage area with high resolution.
The mission aims to map theentire globe every 12 days, providing consistent and detailed data on:
- Ecosystems: Biomass, forest cover changes, and wetlands.
- Ice Mass: Understanding the growth and retreat of glaciers and ice sheets, contributing to sea-level rise.
- Dynamic Surfaces: Movements of the Earth's crust related to earthquakes, volcanoes, and landslides.
- Natural Hazards: Improved monitoring and assessment of various disasters.
- Groundwater: Providing insights into water resources.
The data collected will help researchers understand the capture and release of carbon in both ecosystem types and will be made freely available to the public.
The planned mission duration isthree years,with the satellite orbiting Earth in asun-synchronous orbitat an altitude of747 km.
Conclusion
The NISAR mission is a landmark in international collaboration and radar remote sensing. It is poised to transform our understanding of Earth’s systems through frequent, high-resolution global observations.
Its comprehensive data will support climate science, natural resource management, and disaster resilience for years to come.