NASA-ISRO Radar Satellite Captures First Image of Mount Desert Island

The NISAR (NASA-ISRO Synthetic Aperture Radar) Earth-observing radar satellite's L-band synthetic aperture radar (SAR) system captured this image of Mount Desert Island off the Maine coast on Aug. 21, 2025. Dark areas represent water, green areas are forest, and magenta areas are hard or regular surfaces, such as bare ground or buildings. The bright magenta area on the island's northeast end is the town of Bar Harbor. The satellite is a joint effort between NASA and the Indian Space Research Organisation (ISRO) and is the first satellite to combine L-band and S-band radar systems. The L-band system uses a 10-inch (25-centimeter) wavelength that enables its signal to penetrate forest canopies and measure soil moisture as well as motion of ice surfaces and land down to fractions of an inch – a key measurement in understanding how the land surface moves before, during, and after earthquakes, volcanic eruptions, and landslides. The S-band radar, provided by ISRO's Space Applications Centre, uses a 4-inch (10-centimeter) microwave signal that's more sensitive to small vegetation, which makes it effective at monitoring certain types of agriculture and grassland ecosystems. Data used to create the image was collected during NISAR's commissioning phase, when the spacecraft's systems and instruments are powered on and tested. The NISAR mission will begin science operations in November, roughly 90 days after its July 30, 2025, launch from Satish Dhawan Space Centre on India's southeastern coast. Observations from NISAR will benefit humanity by helping researchers around the world better understand changes in our planet's surface, including its ice sheets, glaciers, and sea ice. It also will capture changes in forest and wetland ecosystems and track movement and deformation of our planet's crust by phenomena such as earthquakes, landslides, and volcanic activity. The global and rapid coverage from NISAR will provide unprecedented support for disaster response, producing data to assist in mitigating and assessing damage, with observations before and after catastrophic events available in short time frames. https://photojournal.jpl.nasa.gov/catalog/PIA26616