Scientists report that Neptune’s moon Nereid may be among the planet’s original moons that survived a long-ago disruption. Neptune has 16 known moons. The largest, Triton, is believed to have arrived from the colder outer regions of the solar system billions of years ago, an event that could have scattered Neptune’s earlier moon population and driven many of them into destructive collisions.
Using NASA’s James Webb Space Telescope, a research team led by the California Institute of Technology observed Nereid to test whether it resembles a “party crasher” like Triton or instead fits a picture of an older, native moon. According to the study findings described across outlets, the measurements are consistent with Nereid having a different origin from Triton and likely surviving the chaotic period rather than being captured during Triton’s arrival.
While the reports summarize a likely scenario for Nereid’s history, they frame the conclusion as based on Webb observations and comparisons tied to the dynamics of Triton’s past intrusion into the Neptune system.
