Technical Details
Nereid, a moon of Neptune, likely survived in the planet's original system rather than being captured from the Kuiper Belt, a region of icy bodies beyond Neptune's orbit. This conclusion was reached by researchers publishing in Science Advances on May 20, based on data from NASA's James Webb Space Telescope.
Context and Background
Long believed to have been captured by Neptune's gravity from the Kuiper Belt, like Triton, Neptune's largest moon, the capture would typically disrupt or eject other orbiting bodies, making the survival of an original moon unlikely.
Industry Impact
The irregular and highly elongated orbit of Nereid supported this view. Noted by Gerard Kuiper in 1949, when he discovered the moon, he wrote: 'There are grounds to hope that this object may be a key to the unusual cosmogonic problem presented by Neptune's system.'