Astronomers have made a fascinating new discovery in the far reaches of our solar system. Even farther than Pluto, they’ve found a mysterious, planet-sized object nicknamed “Ammonite.” This frozen world might change what scientists believe about the solar system’s past—and even about the possible existence of the elusive “Planet 9.” Curious? Let’s break down what makes Ammonite such a big deal.
Table of Contents
Discovery
In 2023, a team of Japanese astronomers from the National Astronomical Observatory discovered a strange new object using the powerful Subaru Telescope in Hawaii. The object was originally labeled 2023 KQ14, but until it gets an official name, researchers are calling it Ammonite—just like the spiral-shaped fossils it resembles in shape.
Later, in July 2024, astronomers used the Canada-France-Hawaii Telescope to track its motion and orbit more closely. What they found stunned them.
Sednoid
Ammonite is what scientists call a sednoid—a type of space object with a very unusual orbit. Sednoids travel in long, stretched-out paths around the Sun and stay incredibly far away from it. They never come closer than Neptune, one of the farthest planets in our solar system.
Famous sednoids like Sedna and 2012 VP113 already had astronomers scratching their heads. Now, Ammonite has joined that mysterious group, but with an orbit that’s different from the rest.
Orbit
What’s so special about Ammonite’s orbit? It doesn’t match the patterns seen in other known sednoids. That’s important because it may mean that some of the current ideas about how these objects move—and what might be influencing them—need to be rethought.
Planet 9
One big theory that’s been floating around for years is the idea of Planet 9. Scientists have wondered whether a huge, unseen planet way out beyond Pluto could be tugging on sednoids like Sedna, shaping their orbits with its gravity.
But here’s the twist—Ammonite doesn’t follow the same orbital path as the others. Its odd movement might actually weaken the case for Planet 9. If a big hidden planet were out there, it should be affecting all sednoids in a similar way. But Ammonite refuses to follow that pattern.
Ejection
There’s another possibility. Some researchers suggest that our solar system used to have a giant planet, but it was somehow ejected into space billions of years ago. If that happened, it could explain why these far-off objects like Ammonite have such strange orbits today.
So instead of Planet 9 existing now, maybe it’s long gone—thrown out of the solar system during its chaotic early years.
History
Dr. Fumi Yoshida from the Chiba Institute of Technology says Ammonite and objects like it are like time capsules from the birth of the solar system. Their strange paths tell us that something unusual happened out there a long time ago, and we’re still feeling the effects today.
Naming
Right now, the name Ammonite is just a nickname. The official name will eventually be chosen by the International Astronomical Union (IAU), the group in charge of naming space objects. Until then, the discovery of Ammonite reminds us just how much of the solar system we haven’t explored—and how many surprises are still out there.
Every time we find something new in deep space, it gives us a chance to ask better questions, test bold theories, and rethink what we thought we knew. And in that sense, Ammonite is more than just a distant object—it’s a symbol of discovery itself.
FAQs
What is Ammonite in space?
A newly found planet-size object beyond Pluto.
Is Ammonite officially named yet?
No, it’s waiting for an official IAU name.
What is a sednoid?
A space object with a far, stretched-out orbit.
Does Ammonite support Planet 9 theory?
Not really, its orbit challenges that idea.
Where was Ammonite discovered?
Using the Subaru Telescope in Hawaii.
