Kit KittlestadJun 28, 2025 5 min read

40% Chance Planet Nine Exists – New Evidence Rising

Ninth planet of the solar system opened. New gas giant. Elements of this image furnished by NASA
NASA via Adobe Stock

Ever since Pluto got demoted from its planetary status, space fans have been holding out hope for a new ninth planet to fill the void. Turns out, there’s a growing Planet Nine probability that has scientists and skywatchers buzzing again. 

According to a recent study based on thousands of computer simulations, there’s a 40% chance Planet Nine really is out there, lurking far beyond Neptune. And that’s not a random number. It’s based on solid science, dynamic modeling, and a dash of cosmic chaos theory.

Researchers from Rice University and the Planetary Science Institute suggest that our solar system may naturally give rise to “wide-orbit” planets, ones that were flung way out during the early days of planetary formation, but didn’t quite get ejected into interstellar space. 

Instead, they got stuck in super distant orbits, quietly circling the Sun for billions of years, just waiting to be found.

40% Chance Planet Nine Exists – What You Need to Know

Colorful solar system with nine planets and satellites. Astronomy banner with planet stand in row in bizarre plasma clouds. Galaxy discovery and exploration. Elements of this image furnished by NASA.
NASA via Adobe Stock

Here’s a fun notion: we can think of the early solar system as a very chaotic pinball machine. When the giant planets like Jupiter, Saturn, Uranus, and Neptune formed, they didn’t do so politely. They shoved and jostled one another around and, in all that cosmic pushing and pulling, some protoplanets got tossed out to the edges. 

If the timing and surrounding gases were just right, a few of those planetary runaways might not have escaped entirely. Instead, it seems they settled into distant, stable orbits. At least, that’s the main idea behind the Planet Nine simulations.

Lead researcher André Izidoro put it like this: when planets scatter each other, one or more can get trapped far away, instead of being kicked out of the solar system entirely. And that trapping process, the team believes, could very well explain how a Planet Nine-like object might exist, bringing us to that fascinating 40% chance Planet Nine is real.

Clues from Kuiper 

The main reason scientists have suspected an unseen planet for years is Kuiper Belt clustering. The Kuiper Belt is a vast ring of icy objects and dwarf planets beyond Neptune, and many of these objects, like Sedna, have orbits that are oddly tilted and elongated in the same way. It’s as if something massive out there is pulling at them, herding them into formation.

This gravitational nudge hints at a planet that may be five to ten times larger than Earth, hiding out in the dark. It's like spotting tree branches bending in the wind, knowing something invisible must be pushing them. Sure enough, Planet Nine might be doing the same kind of thing out in the Kuiper Belt.

A Glimmer In the Infrared

In May, scientists started sifting through old infrared telescope data and found hints of something suspicious. These were subtle clues – faint blips in long-archived images from observatories that are no longer active. 

Still, they offered tantalizing signs of an infrared Planet Nine candidate. Infrared is ideal for spotting cold, distant objects like this because they don’t reflect much visible light but still emit heat.

Of course, these hints, alone, aren’t enough for a discovery, but they add to the growing pile of circumstantial evidence. All eyes are now turning toward a new technological marvel that could finally settle the question.

The Vera Rubin Era Begins Soon

Enter the Vera Rubin Observatory, set to begin its sky survey in late 2025. With the world’s most powerful camera, it will scan the heavens with unprecedented detail, turning up objects far too faint for any previous telescope to detect. Its wide-field view and repeated coverage of the night sky make it a perfect tool in the Vera Rubin Observatory hunt for Planet Nine.

If Planet Nine exists, Rubin’s telescope has a real shot at spotting it, or at least helping to rule it out once and for all. Either way, this next-gen observatory could rewrite our solar system’s map.

Why Pluto Isn’t Planet Nine

While we’re talking about outer solar system mysteries, we should clear something up: poor little Pluto isn’t making a comeback as the ninth planet. Back in 2006, astronomers reclassified it as a dwarf planet for a reason. 

Once Eris was discovered, an object about the same size as Pluto, located even farther out, the logic shifted. If Pluto remained a planet, so would Eris, Haumea, Makemake, and others. Then, we’d be juggling way more planets than expected.

So, the real ninth planet, if there is one, will be something completely different: likely a massive, icy giant, with a proper orbit and planet-scale influence. And that’s where the idea of Planet Nine steps in, a worthy candidate to reclaim the “ninth planet” title.

Pluto. Dwarf planet of the solar system. The elements of this image furnished by NASA.
NASA via Adobe Stock

Is Planet Nine Out There?

That’s the million-dollar question. With the Planet Nine probability now pegged at 40% by these new simulations, it’s no longer a fringe idea. Scientists aren’t just chasing shadows. They’re following consistent orbital patterns, computer models, and even infrared candidates. It looks like the upcoming data from the Vera Rubin Observatory could be a real game-changer.

Whether or not Planet Nine reveals itself, the search is shedding light on how planetary systems form, evolve, and sometimes fling their members to the far reaches of outer space. Either way, let’s keep our telescopes ready. There’s still a lot to discover in our cosmic backyard.

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