NASA-ISRO Synthetic Aperture Radar

Q. What is the news?

A. The NASA-ISRO Synthetic Aperture Radar satellite, aimed at making global measurement of land surface changes using advanced radar imaging, is proposed to be launched in early 2023. 

Q. What is NASA-ISRO SAR?

A. 

• NISAR is a joint collaboration for a dual-frequency L and S-band SAR for earth observation.
• NASA and Bengaluru-headquartered ISRO signed a partnership on September 30, 2014, to collaborate on and launch NISAR.
• The mission is targeted to launch in early 2022 from ISRO’s Sriharikota spaceport in Andhra Pradesh’s Nellore district, about 100km north of Chennai.
• It is capable of producing extremely high-resolution images for a joint earth observation satellite mission with NASA.
• It will be the first satellite mission to use two different radar frequencies (L-band and S-band) to measure changes in our planet’s surface less than a centimeter across.

Q. What are the Objectives of the NISAR?

A. 

• NISAR will observe Earth’s land and ice-covered surfaces globally with 12-day regularity on ascending and descending passes, sampling Earth on average every six days for a baseline three-year mission.
• It will measure Earth’s changing ecosystems, dynamic surfaces, and ice masses, providing information about biomass, natural hazards, sea-level rise, and groundwater, and will support a host of other applications.
• It would also provide data on natural hazards including earthquakes, tsunamis, volcanoes, and landslides.

Q. What are L and S Bands?

A.

• L band waves are used for GPS units because they are able to penetrate clouds, fog, rain, storms, and vegetation.
• The S-band is used by airport surveillance radar for air traffic control, weather radar, surface ship radar, and some communications satellites, especially those used by NASA to communicate with the Space Shuttle and the International Space Station.
• NISAR uses a sophisticated information-processing technique known as SAR to produce extremely high-resolution images.
• Radar penetrates clouds and darkness, enabling NISAR to collect data day and night in any weather.

Q. What is collaboration?

A.

• NASA is providing the mission’s L-band SAR, a high-rate communication subsystem for science data, GPS receivers, a solid-state recorder, and payload data subsystem.
• ISRO is providing the spacecraft bus, the S-band radar, the launch vehicle, and associated launch services for the mission, whose goal is to make global measurements of the causes and consequences of land surface changes using advanced radar imaging.