NISAR radar reveals months of change in a Kamchatka lava field

NASA released the sequence on September 24. Its 17 selected observations span December 25, 2025, to August 17, 2026; the newly published view records an older eruption.

The joint NASA–Indian Space Research Organisation satellite supplies a particularly useful kind of continuity. Radar can observe through cloud and darkness, conditions that interrupt optical imaging. NASA describes views from two orbital directions during each 12-day cycle. The resulting sequence makes change legible across months, while the gaps between observations remain part of the evidence.

Brightness needs a careful reading. A strong return from the lava field says something about how the surface reflects radar. It does not show glowing rock, measure its temperature or establish how much material erupted. The apparent movement of a bright boundary and a quantitative estimate of ground displacement are different results, requiring different analyses.

The route from looking to investigating is unusually open. NASA’s original sequence supplies the dates and credits; the Alaska Satellite Facility’s Vertex service lets readers search the L-band archive geographically. Downloads require a free Earthdata account. A small area and a limited date range make a more useful first investigation than an indiscriminate collection of files.

The accompanying product documentation is essential reading. Earlier beta products and later provisional products differ in processing and calibration. A change across that boundary could belong to the data pipeline as well as the volcano. The opportunity is to examine a landscape repeatedly, with enough documentation to challenge the first interpretation.