If you follow any media outlets, you’ve likely heard we found a new planet. That’s exciting news.
Except, we actually haven’t. Not yet, at least.
Contrary to what most popular news outlets are saying, we haven’t officially found a new planet in our solar system just yet. What we have found is a lot of really convincing evidence that there might be an undiscovered planet out there.
Don’t get me wrong, this is still exciting news, but until we collect more data and directly observe this “Planet Nine,” we can still only officially say there are eight planets we know of in our solar system.
Let’s dig into what we know so far. According to scientists Konstantin Batygin and Michael E. Brown, in their paper “Evidence for a Distant Giant Planet in the Solar System” published in The Astronomical Journal, the existence of a relatively large planet outside the orbit of Neptune would explain the peculiar orbits of several bodies in the Kuiper Belt.
What’s the Kuiper Belt, you say? I’m glad you asked.
Similar to the Asteroid Belt, the collection of large rocky bodies in between Mars and Jupiter, The Kuiper Belt consists of large icy bodies in between the orbit Neptune and the infinite nothingness of space. You might have heard of one of these bodies, Pluto. The Kuiper Belt extends pretty far out into space.
For some perspective, the Earth is about 93 million miles from the Sun, while Neptune is about 2.8 billion miles from the Sun. The Kuiper Belt extends from just after Neptune’s orbit to 4.65 billion miles from the Sun. Some Kuiper Belt objects extend even further than that. It’s these distant bodies that makes scientists think Planet Nine is out there.
The orbits of several of these bodies are all highly elliptical, which just means their orbits are big ovals that come close to the sun then swing far out towards the edges of the Solar System. They all swing out in relatively the same direction and come closest to the sun in relatively the same place. Though there are some variations in length of the orbits, they have the same angle of tilt relative to the sun. According to the scientists, there’s a 1 in 14,285 chance that orbits this similar would occur randomly. Though possible, it’s more likely something is manipulating their orbits.
That’s where Planet Nine comes in.
The scientists, after creating some models, concluded a ninth planet outside the orbit of Neptune could gravitationally “shepherd” these bodies into their similar orbits. The models predict the planet’s mass would be about 10 times larger than Earth’s. And it’s no wonder we haven’t seen it yet- this planet’s orbit would be huge. Neptune, being 2.8 billion mile distance from the sun, takes about 162 years to complete one orbit, while Planet Nine might reach a distance of 20 billion miles from the Sun and take between 15,000-20,000 years to complete one orbit.
But again, none of this has been proven just yet.
Personally, I don’t understand is why everyone is losing their mind over a planet we’re not sure even exists when we’ve confirmed the existence of planets orbiting stars trillions upon trillions of miles away. The Kepler Space Telescope has detected over 1,000 planets outside the Solar System, some of which are likely capable of supporting life.
Don’t get me wrong, the possibility of discovering a new planet in our own backyard excites me, but the thought of finding new life forms, on planets we know exist, to study or maybe even talk to excites me way more. So unless this is the planet David Bowie went home to, I’d appreciate a photo to at least look at.
Finally, let’s talk Pluto. Some of you may feel Pluto is being replaced, but let’s be clear, Pluto was mis-categorized as a planet in the first place. It was one of the first Kuiper Belt objects ever discovered. Naturally, we jumped at the chance to claim the discovery of a new planet, kind of like now. We speculated about its size and composition before we had any good data or even got a decent look at it, kind of like now. Pluto is far more like its brothers and sisters in the Kuiper Belt than any of the planets. If Pluto’s big heart, seen by the New Horizons probe, tells us anything, Pluto is happy with his family.
We’re all very excited about the possibility of discovering a new planet, as we should be. But—and this is coming from one of the biggest space nerds on campus—can we all calm down a bit until we get some more
solid evidence? In the meantime, I’m going to keep my eyes and ears open for the confirmation. Maybe I’ll even grab a telescope and look for Planet Nine myself.
Featured image credit: Sweetaholic/pixabay