Webb Telescope Suggests Neptune's Moon Nereid Is Sole Survivor of Ancient Lunar System

More than four billion years ago, the arrival of Triton into Neptune's gravitational embrace is thought to have shattered an entire world of moons, leaving behind only chaos and fragments. Now, the James Webb Space Telescope has turned its infrared eye toward Nereid — Neptune's third-largest moon — and found in its icy surface a chemical signature that speaks not of the distant Kuiper Belt, but of an older, more intimate origin. If the evidence holds, Nereid may be the sole surviving witness to a solar system that existed before catastrophe rewrote Neptune's sky, a relic preserved by the accid