A partnership between the United States’ NASA and India’s ISRO is poised to transform Earth observation and disaster response with the launch of the NISAR (NASA-ISRO Synthetic Aperture Radar) satellite. This advanced satellite will meticulously monitor changes to Earth’s surface, glaciers, sea ice, vegetation, and ice sheets, capturing details as small as “fractions of an inch.”
Equipped with state-of-the-art radar technology, NISAR will provide unprecedented insights into Earth’s dynamic processes by monitoring land and ice-covered surfaces every 12 days. It will track geological movements, like earthquakes, landslides, and volcanic activities, while also observing changes in ecosystems, such as forests and wetlands, and monitoring infrastructure stability.
Scheduled for launch early next year from the Satish Dhawan Space Centre in Andhra Pradesh, India, NISAR will enter low Earth orbit via ISRO’s GSLV Mark II rocket.
Key Features of NISAR
NISAR is the first satellite to carry two advanced radar systems: an L-band radar from NASA’s Jet Propulsion Laboratory (JPL) and an S-band radar from ISRO. These radar systems enable it to capture images day and night, even through clouds—an advantage over traditional optical sensors.
The L-band radar can also penetrate dense vegetation, making it especially useful for tracking ground motion in areas obscured by plant cover, such as volcanic regions or fault lines.
By combining NISAR’s data with other satellite measurements, scientists will gain a clearer view of Earth’s surface changes both horizontally and vertically, which will provide insight into Earth’s crust dynamics and highlight areas at risk of earthquakes and volcanic eruptions.
NISAR’s data will also help detect early warning signs of structural damage, such as levee shifts, or precursors to landslides, offering a more comprehensive picture of surface changes over time.
According to Cathleen Jones, NISAR’s applications lead at NASA’s JPL, “This kind of regular observation allows us to monitor Earth’s surface movement across nearly the entire planet.” This frequent, precise data will enable researchers to study subtle geological shifts, potentially identifying regions susceptible to earthquakes, volcanic activity, or landslides.
Although NISAR cannot predict earthquakes, its data will allow scientists to pinpoint fault lines that show unusual movement, highlighting areas that might experience seismic events. In areas with known seismic risks, like California, NISAR can help focus monitoring on high-risk zones, while in less studied areas, it could reveal new regions vulnerable to earthquakes. In the event of an earthquake, data from NISAR will enable researchers to understand how the fault moved.
In regions such as the Himalayas, where seismic risks are significant, NISAR’s data will offer critical information about potential earthquake hazards. “The area has produced major earthquakes in the past, and NISAR will provide unprecedented information on Himalayan seismic risks,” said Sreejith K M, ISRO’s Earth science lead for the project.
For volcano researchers, NISAR will be invaluable in monitoring surface deformations, such as bulging or sinking, caused by magma movement, providing insights into potential volcanic eruptions.
Supporting Infrastructure Safety
Beyond natural hazards, NISAR will contribute to infrastructure safety by helping monitor critical structures like levees and aqueducts. By identifying subtle shifts in these structures, NISAR’s data can guide inspections and maintenance more precisely, which saves resources and focuses efforts on areas of concern.
In post-disaster scenarios, such as after an earthquake, NISAR can quickly identify compromised infrastructure across large areas, supporting rapid and targeted emergency responses. For example, it could monitor California’s Sacramento-San Joaquin River Delta, with over a thousand miles of levees, to quickly pinpoint areas in need of urgent repair.
This landmark collaboration between the US and India showcases the power of international partnerships in tackling global challenges. NISAR’s mission will be jointly managed, with JPL overseeing the US contributions and high-tech instruments, while ISRO’s U R Rao Satellite Centre in Bengaluru handles the spacecraft and launch operations.