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  • If you think you know how the Solar System is arranged, think again.

  • Because there just might be a Planet X lurking well beyond Neptune.

  • Hey guys, Amy here for DNews.

  • Most of us grew up with nine planets.

  • Then Pluto became a dwarf planet along with the other Kuiper Belt objects and the layout

  • of our Solar System changed: Now we've got eight planets and hundreds of dwarf planets.

  • All of these objects orbit the Sun more or less regularly.

  • Their orbits are all slightly elliptical and vary in inclination, but lets call that regular.

  • Because there are objects beyond the Kuiper Belt that have extremely irregular orbits,

  • and they're throwing a bit of a wrench in how we imagine the Solar System is arranged.

  • Sedna is a dwarf planet that traces a highly elliptical orbit around the Sun.

  • 1 Astronomical Unit, or AU is the distance from the Earth to the Sun.

  • Sedna only comes as close as 76 AU to the Sun and goes as far out as 940 AU.

  • And it's got a companion out there, a recently discovered dwarf planet called 2012 VP113

  • that only comes as close as 80 AU from the Sun and travels as away as 452 AU.

  • There are a small handful of other bodies with similarly strange orbits, and the question

  • plaguing astronomers is why: why are those bodies unlike all the other bodies?

  • They aren't part of a distant debris field, they're too far from Neptune to have their

  • orbits perturbed by Neptune, and they're too far from the Oort cloud.

  • It's possible a passing star pulled them away from the Kuiper Belt at some point.

  • Or it's possible there's a massive planet out there that not only pulled these objects

  • into their irregular orbits but is also keeping them in their strangely distant place.

  • It's far too early to tellastronomers will need to make a lot more observations

  • to confirm anythingbut studying the irregular orbits of these distant tiny worlds could

  • uncover the existence of a ninth planet in our solar system.

  • Or tenth, depending on your feelings about Pluto.

  • The discovery of 2012 VP113 is adding compelling evidence to this idea.

  • This isn't a new way of looking for planets.

  • It's actually how Neptune was discovered.

  • Neptune's orbit was predicted based on irregularities observed in Uranus' orbit; lo and behold the planet was there.

  • Irregularities in Neptune's orbit led to the prediction of an even more distant Planet X.

  • Pluto was actually found near this predicted planet but is too small to really act on Neptune.

  • So could the irregularities in these dwarf planets, when taken together, reveal a new

  • Planet X orbiting our Sun in our own cosmic backyard?

  • It might be a long shot, but it's not impossible!

  • So how do you guys feel about our ever-changing Solar System?

  • Let us know in the comments below or you can catch me on Twitter as @astVintageSpace.

  • And don't forget to subscribe for more DNews every day of the week.

If you think you know how the Solar System is arranged, think again.

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Did We Find Another Planet In Our Solar System?

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    Jerry Liu posted on 2019/05/18
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