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

因為在海王星之後可能還潛伏一顆 X 行星。

Hey guys, Amy here for DNews.

嘿，大家好，Amy 與你們同在 DNews。

Most of us grew up with nine planets.

我們大多數都是與九大行星一起長大。

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

之後冥王星與其他古柏帶的天體成為矮行星，

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

所以我們太陽系的排列出現變化：現在，我們有八大行星和數百顆矮行星。

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

這些所有天體基本上是有規律地繞太陽運行。

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

他們的軌道都是略為橢圓形，而且傾斜度不同，但我們視那為正常。

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

因為古柏帶外有不少天體有著極度不規律的軌道，

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

我們在設想太陽系如何排列時，它們增添了不少麻煩。

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

賽德娜是矮行星，描繪出太陽周圍非常大的橢圓軌道

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

1 天文單位，簡稱 AU，是從地球到太陽的距離。

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

賽德娜只距離太陽 76 AU，最遠的可到 940 AU。

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

而且它那邊有一個朋友，近期發現一個叫 2012 VP113 的矮行星，

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

距離太陽 80 AU，最遠可到 452 AU。

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

還有一小部分的天體，有著類似的奇怪軌道，

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

而困擾天文學家的問題是：為什麼那些天體與其他的不同？

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

它們不是碎片場的一部分．它們離海王星太遠，

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

無法受海王星的干擾，而且也離歐特雲太遠。

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

在某些時候，經過的恆星可能將它們拉離古柏帶。

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

或者那裡可能有一個巨大行星，不僅將這些物體拉到

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

不規則的軌道上，還將它們留在奇怪又遙遠的地方。

It's far too early to tell — astronomers will need to make a lot more observations

現在還太早下定論，天文學家需要做更多觀察，

to confirm anything — but studying the irregular orbits of these distant tiny worlds could

才能確定任何事，但研究這些既遙遠又微小世界的不規則軌道，

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

可以揭開在我們太陽系中，第九行星的存在。

Or tenth, depending on your feelings about Pluto.

或者是第十行星，取決你對冥王星的感受。

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

2012 VP113 的發現為這想法添上了有力的證據。

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

這並不是找尋行星的新方式。

It's actually how Neptune was discovered.

這其實是發現海王星的方法。

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

基於天王星軌道上觀測到的不規則性，才預測出海王星的軌道，完全沒想到有行星在那。

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

海王星軌道的不規則性，預測出甚至更遙遠的 X 行星。

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

冥王星其實是在這預測到的行星附近發現，但它太小無法真正作用於海王星。

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

所以，這些矮行星的不規則性聚集在一起時，能夠找出新的

Planet X orbiting our Sun in our own cosmic backyard?

X 行星，在我們的宇宙後院繞著太陽運行嗎？

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

希望可能很渺茫，但不是天方夜譚！

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

那你們對千變萬化的太陽系有什麼想法？

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

在下方留言讓我們知道．或是你可以上推特找我 @astVintageSpace。

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

最後別忘了訂閱，才能看到 DNews 每天的內容。