NASA-ISRO NISAR Satellite

Syllabus: GS3/ Science and Technology

Context

• The Indian Space Research Organisation (ISRO) is set to launch the NISAR satellite from Sriharikota on July 30 onboard a GSLV Mk-II rocket.

NISAR Satellite

• NISAR is an Earth-observation satellite that stands for NASA-ISRO Synthetic Aperture Radar.
• It is Jointly developed by the National Aeronautics and Space Administration (NASA) and the Indian Space Research Organisation under a partnership agreement signed in 2014.
• It will be launched into a polar Sun-synchronous dawn-dusk orbit at 747 km altitude and an inclination of 98.4º.
• NISAR is the first satellite mission to collect radar data in two microwave bandwidth regions, called the L-band and the S-band.
  • The S-band payload has been made by the ISRO and the L-band payload by the U.S. 

Monitoring of Earth Surface

• The NISAR system comprises a dual frequency, fully polarimetric radar, with an imaging swath greater than 150 miles (240 km). 
• This design permits complete global coverage every 12-days, allowing researchers to create time-series interferometric imagery and systematically map the changing surface of Earth.
  • It can monitor various aspects in very high resolution.
• After a 90-day commissioning period, the mission will conduct a minimum of three full years of science operations with the L-band radar to satisfy NASA’s requirements,
  • ISRO requires five years of operations with the S-band radar.

How NISAR Works?

• NISAR combines two types of Synthetic Aperture Radar (SAR) systems:
  • The L-band SAR (1.257 GHz) uses longer-wavelength radio waves that can penetrate thick vegetation and even soil, making it ideal for observing ground deformation beneath forests.
  • The S-band SAR (3.2 GHz) uses shorter-wavelength radio waves that are more effective at detecting surface details such as crops, water surfaces, and urban infrastructure.
• The satellite also uses polarimetric radar technology, which involves sending and receiving radar signals in both horizontal and vertical polarizations.
  • Satellite operations and commanding will be managed by ISRO, while NASA will provide the orbit maneuver plan and radar operations plan. 

Objectives of the Mission

• NISAR can measure tectonic plate movements accurately. So a lot of geological, agricultural and water-related observations can be obtained from this satellite.
• It can study the water-stressing, climate change-related issues, agricultural changes through patterns, yield, desertification and continental movements precisely with respect to annual water cycle movements. 
• NISAR’s data can help people worldwide better manage natural resources and hazards, as well as providing information for scientists to better understand the effects and pace of climate change. 

Source: TH