The NISAR satellite, a joint project between NASA and the Indian Space Research Organisation ISRO, showed how the eruption of the Krasheninnikov volcano on Russia’s Kamchatka Peninsula developed through a series of radar images captured over several months. An 8.8-magnitude earthquake that struck the nearby ocean on July 30, 2025, is believed to have helped awaken the volcano, which began erupting days later for the first time in about five centuries.
The satellite captured its first image of the volcano on December 25, 2025, while it was completing post-launch tests and transitioning to operational status. Since then, it has revisited the area twice approximately every 12 days, while passing from south to north and then from north to south, enabling changes to be monitored from two directions and at a regular pace.
What Did the Video Show?
Researchers combined 17 frames captured through mid-August into a time-lapse video showing a smaller inner crater filling with lava, then overflowing into a wider crater before the flow spread in a fan shape toward the east. Another flow also appears toward the northwest, believed to have formed before the mission captured its first image.
Each pixel in the images represents an area of approximately 10 square meters, or about half the area of a tennis court. The lava appears lighter because microwaves reflect off it more strongly than they do off the surrounding snow or bare ground.
Why Does This Observation Matter?
The importance of the result lies in the regularity of the measurements, not merely in producing a single image. Synthetic aperture radar can operate without relying on visible illumination, while the satellite’s near-global coverage helps monitor remote volcanoes that do not always have sufficient ground-based instruments. Matthew Pritchard, a member of the mission’s science team and a geophysicist at Cornell University, believes that repeated high-resolution imaging from two directions demonstrates NISAR’s capabilities for monitoring natural hazards.
Technology and Available Data
NISAR relies on two radar systems operating in the L and S bands, making it the first free-flying space mission to combine radars at these wavelengths. The L-band can penetrate tree cover in some cases to observe the ground surface beneath it, while the S-band provides complementary capabilities for observing vegetation depending on leaf size.
L-band radar data products are available through the Alaska Satellite Facility Distributed Active Archive Center, which hosts and distributes NASA’s synthetic aperture radar data. The Jet Propulsion Laboratory JPL, managed by Caltech for NASA, leads the U.S. component of the project, while ISRO provided the spacecraft platform and the S-band radar. The spacecraft carries a cylindrical radar reflector 12 meters wide, the largest NASA has sent into space.
This case illustrates the shift in volcano monitoring from widely spaced, difficult-to-process images to frequently updated data prepared for cloud use. However, the source demonstrates the mission’s monitoring and scientific documentation capabilities, and by itself does not provide evidence that its data were actually used to make a specific evacuation or field-response decision.