Major Evidence of Planet 9 Has Just Been Found

Now, if Earth were the size of a nickel, Neptune would be about as big as a baseball. That's impressive, but it's nothing compared to the giant 9th planet that might be hiding out there. Now, our planet 9's discovery saga might have finally come to an end. Turns out, the problem wasn't where we were looking, but how. And researchers might have just made the biggest solar system discovery in decades. You see, the idea of finding a planet beyond Neptune has been around for years now. I know, back in school, you probably learned that the 9th planet was Pluto. But forget about Pluto, it's been demoted to a less fancy category since 2006. What I'm talking about is the planet 9, a hypothetical giant planet that could be our cosmic neighbor. We've never actually seen it, but scientists are pretty sure it's out there somewhere, hiding in the outer solar system. To explain why they think that, we need a sheet of paper. Hey, here's one. We place a coin on it, and suddenly, it starts to move. Unless we're talking about some kind of superpower, there's no way this coin is moving on its own, right? So, you figure someone must be on the other side, holding a magnet and moving it around. You can't see the magnet, but it explains why the coin is moving. That's kind of what's happening with planet 9. We can't see it, we can't prove it, yet, but its existence could explain the strange movements we see out there in space. For example, the planets in our solar system orbit on a flat plane that's tilted about 6 degrees relative to the Sun. But why 6 degrees? Well, no one really knows for sure. Some scientists think those orbits might be slightly tilted because of the pull of a 9th planet. Its existence could also explain the unusual paths of smaller objects in the distant Kuiper Belt, a region full of icy debris that stretches far beyond Neptune's orbit. Back in 2016, researchers from Caltech published a study about planet 9. They suggested it could have a mass about 10 times that of Earth and follow a highly elongated path. It's a scientific way of saying it takes forever to make one trip around the Sun. Because of that, it would be located in the outer solar system, I mean, far, far away. It would orbit the Sun about 20-30 times farther out than our most distant planet, Neptune. According to scientists, planet 9 would take up to 20,000 Earth years to complete just one full orbit around the Sun. Since it's crazy far out there, it's almost impossible to see it. So as cool as this hypothesis sounds, we've never found solid evidence that planet 9 actually exists. But we might be pretty close. In May 2025, a team at National Tsinghua University might have made one of the most exciting solar system discoveries ever. Alright, so there's a hypothesis that planet 9 hasn't been discovered yet because we haven't been using the right method. This new study raises an interesting question. What if planet 9 actually looks brighter in infrared light than it does in visible light? Let me explain. Scientists have been trying to spot planet 9 by its reflected light. But here's the problem. To spot it in visible wavelengths, sunlight would have to travel all the way out to planet 9, bounce off its surface, and then travel all the way back to Earth. If a Neptune-sized planet were about 10 times farther away than Neptune, it would look about 10,000 times fainter. But a planet's own thermal radiation, I mean, its heat, only has to make a one-way trip. So in infrared light, planet 9 would only be about 100 times fainter. That's why it makes more sense to look for it using space-based infrared telescopes. And that's the idea behind this new study. The team started digging through archives, searching for old infrared sky survey data, and they pulled it from two main sources. First, IRIS, a satellite launched in the 80s that scanned the sky for almost a year. Then, the Japanese satellite Akari, another infrared observatory that operated between 2006 and 2011. So basically, they compared objects that showed up in IRIS' database and noticed which ones had moved by the time Akari took its observations. And by doing that, the researchers found something incredible – an object that might just be our long-lost 9th planet. Because if something moves, it could be a planet orbiting the Sun, right? And yeah, they did find some celestial objects showing tiny movements. But before jumping to conclusions, they had to rule out the parallax effect. And that's something really important when we're talking about solar system discoveries. To explain it, I need you to do something. Hold one finger in front of your face, close one eye, and now switch. Your finger seems to move a tiny bit, right? That's because you're looking at it from a slightly different angle – from one eyeball to the other. The same thing happens when we look out into space from Earth. Since our planet orbits the Sun, our view of very distant objects shifts just a little. That effect is called parallax. My point is, because of this effect, planet 9 would appear to move across the sky as Earth goes around the Sun. On any given day, it might seem to be in one spot, but six months later, when Earth is on the opposite side of the Sun, it would look like it shifted. Six months after that, it would seem to move back again. Scientists had to account for parallax. Actually, they had to remove its effects. So the team looked at images of the sky taken on the same date every year. Because on that same date, Earth is always in the same spot in its orbit. That means, if planet 9 is real, it would show up in the same place in those images every year. No fake wiggle from parallax, just its real position. This careful search led them to a single object – a tiny dot in the infrared data. This strange little spot had moved slightly along its orbit around the Sun over the 23 years between Iris and Acheri. Wait, could that be it? Did astronomers just confirm a hidden planet? Well, maybe, but don't get too excited. The data we have on its motion over that time is not enough to figure out its full orbit. So for now, we still can't say for sure if this mysterious object is really planet 9. It's definitely a strong candidate, though. Based on how bright the object appears, the team estimates it could be pretty massive. And that came as a big surprise. You see, previous NASA research ruled out any Jupiter-sized or Saturn-sized planets hiding out there. But a smaller world would've gone undetected. So the scientists were looking for something just a bit bigger than Earth. But it turns out, this mysterious planet might be more massive than Neptune. Now that they've discovered planet 9, supposedly at least, the plan is to keep tracking it and collecting new data. But don't think the road ahead will be easy. Because since the ACARI satellite spotted it for the first time, that object didn't just sit still. It's been moving slowly through space ever since. So now, scientists need to use regular telescopes on Earth to look for it again. And here's the tricky part. They're not exactly sure where it moved to. So they have to search a pretty big patch of the sky. And so far, no matching object has been found. Whether this really turns out to be the planet 9 discovery or not, only time will tell. For now, its existence is still up for debate. But with powerful new technology on the way, like NASA's Nancy Grace Roman Space Telescope, astronomers are more determined than ever to uncover the truth. And if planet 9 really is out there, hiding in the cold dark edges of our solar system, it's running out of places to hide. That's it for today! So hey, if you pacified your curiosity, then give the video a like and share it with your friends. 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