NASA Discovers New Solar System Object Named ‘Ammonite’ In Groundbreaking Find.
Astronomers have uncovered a new celestial body in our Solar System, dubbed “Ammonite” by the team behind its discovery, NASA has announced. Officially designated 2023 KQ14, this distant object, located far beyond Neptune, marks only the fourth known sednoid—a rare class of trans-Neptunian objects with highly elongated orbits. The discovery, made using the Subaru Telescope at the Mauna Kea Observatory in Hawaii, offers fresh insights into the Solar System’s complex history.
The object, estimated to be between 220 and 380 kilometres in diameter, was first spotted in March, May, and August 2023 by the Formation of the Outer Solar System: An Icy Legacy (FOSSIL) project, led by researchers from Japan and Taiwan. Follow-up observations in July 2024, using the Canada-France-Hawaii Telescope, confirmed its orbit, revealing a perihelion of 66 astronomical units (AU)—twice Neptune’s distance from the Sun—and a semi-major axis of 252 AU, meaning Ammonite takes roughly 4,000 years to complete a single orbit. Its unique trajectory, which differs markedly from other sednoids like Sedna, suggests a diverse and dynamic outer Solar System, shaped by ancient cosmic events.
Dr Fumi Yoshida, leader of the FOSSIL project, described the find as a window into the Solar System’s formative years, noting that Ammonite’s orbit in a region minimally influenced by Neptune’s gravity hints at extraordinary historical forces, possibly a passing star or an ejected planet. Dr Shiang-Yu Wang, a research fellow at Taiwan’s Academia Sinica Institute of Astronomy and Astrophysics, added that the discovery’s significance lies in its potential to unravel the mysteries of the Solar System’s early evolution. Unlike the other three known sednoids, Ammonite’s orbit is oriented in the opposite direction, challenging existing theories, including the hypothesis of a distant Planet Nine.
The discovery, published in the peer-reviewed journal *Nature Astronomy*, has sparked excitement among astronomers. Dr Ying-Tung Chen, a support scientist at Academia Sinica, emphasized that Ammonite’s distinct orbital path underscores the complexity of the outer Solar System, urging further study to determine what sculpted these unusual trajectories. While the object’s composition remains unconfirmed, experts suggest it is likely composed primarily of rock and ice, typical of sednoids.
NASA’s involvement traces back to the discovery of Sedna in 2003, which first hinted at the existence of such distant objects, potentially part of the hypothesised Oort Cloud. Ammonite’s identification reduces the likelihood of the Planet Nine theory, as its orbit does not align with the clustering seen in other sednoids, according to Dr Yukun Huang of the National Astronomical Observatory of Japan. However, the find fuels ongoing debates about the forces that shaped our Solar System billions of years ago.
The astronomical community is abuzz with optimism, with researchers hopeful that advanced telescopes like the Subaru will uncover more such “fossils” of the Solar System’s past. As Dr Wang noted, each discovery like Ammonite brings scientists closer to piecing together the full story of our cosmic neighbourhood’s origins, cementing its place as a pivotal moment in astronomical exploration.
