Recent scientific analysis suggests that Neptune’s moons Larissa, Galatea, and Proteus may not have formed in their current state, but are instead the fragmented remains of larger icy worlds destroyed during a violent gravitational event. Researchers believe these bodies were decimated when Triton, Neptune’s massive, irregularly orbiting moon, was captured by the planet’s gravity. Acting as a celestial wrecking ball, Triton likely shattered the native moons orbiting Neptune, leaving behind the remnants observed today.

According to Space.com, this theory provides a unique opportunity for planetary scientists to examine the internal composition of icy moons, which are typically shielded by thick outer shells of ice. Because these moons were essentially turned inside out during the catastrophic collision, their inner material is exposed in a way not seen elsewhere in our solar system. Lead author Ryleigh Davis, a researcher at the University of California, San Diego, noted that these inner moons serve as a rare window into the composition of ancient icy worlds.

Using near-infrared data from the James Webb Space Telescope (JWST), the research team identified magnesium-rich phyllosilicates—a type of clay mineral—on the surfaces of the moons and Neptune's rings. This finding is significant, as such minerals had not been previously documented in the outer solar system beyond Jupiter. By studying these specific signatures, astronomers hope to gain a more comprehensive understanding of the turbulent history of the Neptunian system and the mechanisms that shaped its diverse array of satellites.