5 min readImage of the Day for May 21, 2026Satellite imagery shows a surge of new volcanic activity in the ocean near Papua New Guinea.NASA Earth ObservatoryMay 21, 2026 Article
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It’s a truism among oceanographers that there is more accurate mapping of the surface of the Moon and Mars than of the deep-ocean floor. That’s especially true for the Bismarck Sea, a relatively deep body of water north of Papua New Guinea. It's an ocean basin with a geologically complex seafloor rife with faults, volcanic features, rifts, scarps, and active subduction and spreading zones at depths that make high-resolution sonar mapping challenging.
When satellites detected signs of an unexpected submarine volcanic eruption in the Central Bismarck Sea on May 8, 2026, volcanologists were confronted with the reality that no high-resolution maps of the area were available, and relatively little is known about the deep-water eruption setting. The new eruption is thought to be occurring along the Titan Ridge, about 16 kilometers (10 miles) southeast of the location of a submarine eruption in 1972. However, there is little clarity or consensus among scientists about precisely which volcanic feature may be erupting, the original depth of the currently active vent, or when it last erupted.
