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  • In the outskirts of our solar system, billions of kilometers past Pluto, there might be a

  • mysterious planet lurking in the abyss.

  • The hypothetical body is known as Planet X or Planet Nine, and some astronomers have

  • been trying to prove its existence for a good chunk of the last decade.

  • It's believed that the phantom planet has a mass about 10 times that of Earth making

  • it close in size to our ice giants.

  • Like many other celestial objects, Planet Nine is thought to orbit the Sun except it

  • takes a much longer elliptical route, traveling an estimated 20 times farther from the Sun

  • on average than Neptune.

  • NASA says at that distance, it may take between 10,000 and 20,000 Earth years to make one

  • full orbit around the sun.

  • Planet Nine is too far to be observed with a modern telescope, but a planet as big as

  • it's believed to be should leave a trace of its presence in the gravity it exerts on other objects.

  • And that thought process is based off of Sir Isaac Newton's law of universal gravitation,

  • which established that the gravitational force between two bodies is proportional to their masses.

  • This formula essentially shows that an object with a larger mass will have an effect on an

  • object with a smaller mass.

  • Take Jupiter, for example.

  • The gas giant is so large, its gravitational pull impacts the smaller celestial bodies

  • around it, trapping them in its orbit and altering their trajectories.

  • Jupiter's pull is even thought to be the reason why Mars's orbit is slightly elliptical.

  • Planet Nine believers are pointing to Newton's law of universal gravitation as a basis for its existence.

  • Due to the discovery of several distant objects that are behaving in an unusual way.

  • The objects in question are located in the inner Oort Cloud, a mysterious region that

  • surrounds the solar system like a bubble.

  • The group has complimentary orbit patterns that swing far out in the same general direction

  • and then cluster as they round the Sun.

  • It's believed these similarities are a result of Planet Nine's

  • gravitational pull, and a recently discovered dwarf planet is giving more weight to this scenario.

  • The pint-sized planet, nicknamed The Goblin, travels about 2,300 astronomical

  • units away from the Sun at its most distant point and 65 AU at its closest.

  • To put that into perspective.

  • One AU is equal to the average Earth-Sun distance which is about 150 million kilometers.

  • So there are still 9.6 billion kilometers between The Goblin and the Sun

  • at their closest point.

  • Because of this extreme distance, the gravity of the known planets in the outer solar system

  • are unlikely the cause of The Goblin's unusual behavior.

  • So, there has to be something else perturbing these distant celestial bodies, right?

  • Well, while there are a few astronomers that are 90 percent sure Planet 9 is the culprit

  • others aren't so sold on its existence.

  • Some non-believers do think that something is affecting the objects,

  • but say an undiscovered planet probably isn't the cause.

  • For now, the sample size of these distant objects is just too small to draw any conclusions.

  • But NASA says the Oort Cloud may contain more than a trillion icy bodies, so it's likely

  • that new discoveries could increase the possibility of a potential phantom planet.

  • And that's exactly the hope of the Planet Nine hunters.

  • So they'll continue to search for more dwarf planets

  • like The Goblin in their quest for the ultimate astronomical achievement.

  • If you want to see more Space Crafts, check out this playlist here.

  • And be sure to let us know in the comments what astronomical phenomena you want to learn more about.

  • Thanks for watching Seeker!

  • Don't forget to subscribe.

In the outskirts of our solar system, billions of kilometers past Pluto, there might be a

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