Welcome newest member of our Solar System . Ammonite

The solar system suddenly has a new member. A new object discovered in the solar system beyond Neptune and Pluto has astronomers rethinking the history of the solar system. Called 2023 KQ14 and nicknamed “Ammonite,” the discovery of this unique so-called trans-Neptunian object is both unexpected and could reshape what we know about the solar system’s past.

Ammonite is not classed as a planet. It’s not even called a dwarf planet, like Pluto (and Ceres, Haumea, Makemake and Eris). Ammonite is classed as a sednoid — an object similar to Sedna, a dwarf planet candidate in the outer solar system, which was found in 2003.

Like Sedna, Ammonite orbits beyond Neptune and has a highly eccentric orbit. Ammonite is only the fourth sednoid ever discovered

Distance

The solar system is measured in Earth-sun distances, one of which is called an astronomical unit (au). When it was found, Ammonite was 71 au from the sun. That’s about twice as far as Neptune (30 au) and Pluto (40 au). However, Ammonite’s orbital path is highly elliptical, getting as far from the sun as 432 au. It takes about 4,000 Earth-years to complete one orbit of the sun.