Archive images taken by the Hubble Space Telescope have revealed a previously undiscovered moon.
The enigmatic object known as ‘S/2004 N1’ is the first new moon to be found around Neptune in over ten years. It was discovered by SETI’s Mark Showalter who had been examining archive photographs of Neptune to study segments of its rings. The technique involved stacking together multiple short exposure images to help see the rings in more detail.
“I got nice pictures of the arcs, which was my main purpose, but I also got this little extra dot that I was not expecting to see,” he said. The new moon is particularly perplexing because it is so small that it is incredible that it managed to survive the formation of Neptune’s other moons. “The Neptune moons we see today were probably broken up and regenerated after the arrival of Triton,” Showalter added.
Neptune has a new moon, and its existence is an enigma. The object, known for now as S/2004 N1, is the first Neptunian moon to be found in a decade. Its diminutive size raises questions as to how it survived the chaos thought to have created the giant planet’s other moons.