NISAR Satellite: A Joint Venture of NASA and ISRO for Earth Observation

NISAR (Source: NASA/JPL-Caltech)

With many claims by climate scientists of rapid changes in Earth’s ecosystem, there is now a need to accurately monitor Earth’s land, sea levels and ice surfaces with minute details to predict the future of Earth and our destiny on earth. To do this, NASA and ISRO have come together to develop a satellite called NISAR that can provide minute changes on the Earth’s surface.

What is NISAR?

NISAR is short form of NASA-ISRO Synthetic Aperture Radar, which is being developed by NASA (leading institute – Jet Propulsion Laboratory, California) and ISRO (leading institute – U R Rao Satellite Centre, Bangalore). NISAR will map the Earth in 12 days (ascending and descending both) and get the minutes details of the changing ecosystem of Earth. NISAR will use two fully capable Synthetic Aperture Radar (SAR) instruments: A 24 cm wavelength L band SAR (L-SAR) provided by NASA and a 10 cm wavelength S-band SAR (S-SAR) provided by ISRO. L band and S band are the wavelength ranges of Radio waves in the electromagnetic wave spectrum, which is 30 – 15 cm for L band and 15 – 7.5 cm for S band. Thus, NISAR will use two wavelengths to do the imaging: one from L band and another from S band. NISAR will have a ~ 240 km swath, 7 m resolution along track and 2-8 m resolution cross-track (depending on mode). NISAR has baseline mission of 3 years, however, ISRO will use it for 5 years.

What important information will NISAR collect?

Sea ice in the polar regions is changing rapidly enough to be observed in the best detail by the naked eye or by any other means except NISAR, which is expected to provide the dynamics of sea ice change with changing climate. The misbalance in the sea ice formation and melting over weather change will have an impact on the processes that affects the atmosphere and hence are very crucial. Due to the high resolution, NISAR can provide the information even below sea ice changes and other part of the sea to have a monitoring on sea water level changes. It can provide the information used to forecast the weather and can inform about Marine Hazards. The oil spills are the other thing that can be monitored to save people and environment and even to find new oil source location.

NISAR will be able to provide timely snapshots of floods uninterrupted by clouds day and night and give adequate information to flood responders. It can detect floods even under dense forest.

Nowadays, seismic activities are developing even in places where earthquakes have never been reported, but due to resource extraction from the Earth, the earthquake scenario is changing. NISAR will help us locate those areas. The second threat is landslides, which are occurring around the world, causing damage to infrastructure and lives. NISAR will give advance warning about landslides, giving enough time to save lives.

Volcanic eruptions destroy cities, disrupt local agriculture and even its ash clouds disturbs aeroplanes. NISAR will help in monitoring volcanic eruptions in their early stages and planning their response.

NISAR will provide information on the melting of mountain glaciers over time so that timely monitoring of water resources, sea water levels and rivers can be done.

NISAR will map surface soil moisture globally, helping to monitor plants, animals and agriculture. Furthermore, it will map crops being grown globally and thus monitor global food security.

Apart from the above mentioned application areas, NISAR can contribute to various other areas such as ground water resources, fire monitoring, forest resource management, drought, dam and embankment monitoring etc.

NISAR is set to launch in early 2024 from Satish Dhawan Space Centre, Sriharikota, Andhra Pradesh (India).

Wishing a successful launch of NISAR!!