The collaborative NISAR satellite mission, a joint endeavor between NASA and the Indian Space Research Organisation (ISRO), has officially commenced its Earth observation operations. Launched on July 30, 2025, NISAR is now providing highly detailed insights into our planet's surface, marking a significant advancement in understanding Earth's dynamic systems. The satellite is equipped with advanced L-band and S-band synthetic aperture radars (SAR), a dual-frequency system that enables NISAR to observe nearly all of Earth's land and ice surfaces with remarkable frequency, revisiting areas every 12 days.
The L-band radar, with its longer wavelength, can penetrate dense forest canopies and measure soil moisture, while also detecting subtle land movements like ice shifts and tectonic activity. The S-band radar is highly sensitive to changes in vegetation, making it ideal for monitoring agricultural progress and ecological shifts. Together, these complementary radar bands allow NISAR to capture both natural and human-altered landscapes with unparalleled clarity, day or night and through cloud cover.
In August 2025, NISAR delivered its inaugural radar images, showcasing exceptional detail of Mount Desert Island in Maine and agricultural regions in North Dakota. These initial images clearly differentiated between various land cover types, including forests, water bodies, farmlands, and urban infrastructure, demonstrating the satellite's advanced capabilities. The mission's ability to detect changes as small as one centimeter across Earth's surface is crucial for tracking a wide array of phenomena.
The data generated by NISAR is poised to yield critical information for scientists, policymakers, and communities worldwide. Its frequent coverage is vital for tracking natural hazards such as earthquakes and landslides, monitoring agricultural productivity, and assessing the impacts of climate change, including ice-sheet collapse and sea-level rise. The mission's objectives also include measuring woody biomass, understanding wetland extent changes, and characterizing land surface deformation.
The successful commencement of NISAR's operations underscores the power of international partnerships in advancing Earth observation technology. The mission's commitment to making data freely available, typically within days of observation, will accelerate scientific research and support global decision-making for resource management and disaster preparedness. This groundbreaking collaboration between NASA and ISRO sets a new benchmark for global space exploration and Earth science, promising to deepen our comprehension of Earth's intricate and ever-changing systems.