The NISAR Mission Works

The NISAR mission, a groundbreaking collaboration between NASA and ISRO, is set to transform how we observe and understand Earth. Scheduled for launch in March 2025 from ISRO’s Satish Dhawan Space Centre, this advanced dual-band radar satellite will deliver highly precise monitoring of Earth’s land and ice surfaces. Originating from a 2014 agreement, the mission reflects a shared commitment to tracking environmental changes and mitigating the impacts of natural disasters.

How NISAR Works

At the heart of NISAR is a drum-shaped radar antenna reflector spanning 39 feet (12 metres). This reflector focuses microwave signals sent to and received from the Earth’s surface. The satellite operates with two radar systems:

• L-band radar (10-inch/25-centimetre wavelength)
• S-band radar (4-inch/10-centimetre wavelength)

Each wavelength interacts differently with surface features, enabling NISAR to produce detailed, high-resolution images.

Scientific Objectives and Capabilities

NISAR will scan nearly all of Earth’s land and ice surfaces every 12 days, gathering critical data for scientific research.

• Shorter wavelengths: Detect smaller surface features.
• Longer wavelengths: Penetrate larger structures.

This dual capability allows scientists to monitor:

• Ecosystem changes
• Glacier dynamics
• Geological phenomena, such as landslides and earthquakes

Key Mission Contributors

The mission’s success is the result of contributions from several ISRO centres:

• Space Applications Centre, Ahmedabad: S-band SAR instrument
• U R Rao Satellite Centre, Bengaluru: Spacecraft bus
• Vikram Sarabhai Space Centre: Launch vehicle
• ISRO Telemetry Tracking and Command Network: Satellite operations

NASA provides the L-band SAR, the antenna, and advanced data communication systems.

Expected Outcomes

NISAR’s observations will deliver unparalleled insights into Earth’s surface dynamics. Key applications include:

• Tracking ice sheets, sea ice, and forest ecosystems
• Monitoring crustal movements and volcanic activities
• Providing high-resolution imagery, with each pixel covering an area equivalent to half a tennis court

Data Accessibility and Global Impact

NASA will process and store NISAR’s data in the cloud, ensuring free global access for researchers. This open-data policy will significantly enhance disaster response by providing real-time information before and after catastrophic events. The data will also support damage assessment and mitigation strategies.

Future Significance of The Nisar Mission

The NISAR mission exemplifies the power of international collaboration in addressing global challenges. Its contributions to climate change research, environmental monitoring, and sustainable development will have a lasting impact on the scientific community and humanity’s understanding of our planet.