New tiny world beyond Neptune discovered — boosting ‘Planet Nine’ theory

New tiny world beyond Neptune discovered — boosting ‘Planet Nine’ theory

Researchers use the Subaru Telescope in Hawaii to find a small object on the outer edge of the Solar System. Nicknamed “Ammonite," researchers say it could provide more evidence to the hypothetical “Planet Nine" beyond Neptune.

New Dwarf Planets Beyond Neptune in 2025

Ammonite was discovered using the Subaru Telescope in Hawaii, with follow-up confirmation from the Canada-France-Hawaii Telescope. Its orbit and size officially qualify it as a distant dwarf planet. Estimated diameter: 220–380 km Perihelion (closest approach to the Sun): 50–75 AU (1 AU = Earth–Sun distance) Aphelion: ~252 AU Orbit is highly stable and very distant ...