Most of them are small potato shaped pieces of ice and rock.

它們大部分是由冰或岩石所構成的馬鈴薯狀星體

Some are so far away from Neptune that they need 29 years to circle Neptune once.

它們之中有些距離海王星非常遙遠以至於需要29年才能環繞一圈海王星

Almost all of them are asteroids trapped by Neptune's gravity.

且它們大部分幾乎都是被海王星的重力所捕獲的小行星

99.5% of all the mass around Neptune is concentrated in Triton.

海王星所有衛星的質量有99.5%集中在海衛一(Triton)上

It's the 7th biggest moon, and more massive than all other known moons

海衛一是太陽系中第七大已知的衛星,而且它質量大於

in the solar system that are smaller than itself combined.

其他所有小於它的衛星的質量總和

Its surface area is about as big as the mainland of Russia and Australia together.

它的表面積相當於俄羅斯與澳大利亞的國土面積總和

Also, Triton is one of only four objects in the solar system that we know is geologically active.

而且海衛一是太陽系裡的所有已知天體中僅四個會發生地質活動的天體之一

Triton orbits Neptune in the 'wrong' direction, against the rotation of Neptune,

海衛一以一種錯誤的方式繞著海王星,即海衛一的軌道與海王星的自轉方向是相反的

which is unique in our solar system for an object as big as Triton.

這在整個太陽系裡與海衛一質量相當的天體中是獨一無二的

We can conclude from this that Triton hasn't always been a moon of Neptune,

因此我們可以推斷海衛一可能並非一直是海王星的衛星

but probably was a dwarf planet that was forced into submission by Neptune,

海衛一可能曾經是一個矮行星,在太陽系還年輕且混亂的時候,被海王星的重力

when the solar system was younger and more chaotic.

所吸引

The most popular theory here is that Triton was once part of a double system,

另一個更受歡迎的理論指出,海衛一可能曾是一個聯星系統的一部份

when Neptune migrated to the outer edges of the solar system,

當海王星靠近太陽系的邊緣時

its gravity interfered with the double system and catapulted the other object into space,

海王星的引力干擾了這個聯星系統並且把除了海衛一的天體往星空中彈射走

while Triton was forced into orbit.

而海衛一則被迫進入到海王星的軌道上

This would of disrupted the orbits of other Neptune moons rather violently

這有可能劇烈的影響了海王星其他衛星的軌道

and would most likely have either pushed them away from Neptune,

而很有可能將海王星其他的衛星推離海王星

or let them collide or crash into Neptune.

或是讓它們一頭栽進海王星

This would explain why Neptune's moons are so dominated by Triton.

這也解釋了為什麼海王星的衛星幾乎都受到了海衛一的支配

But, this will end one day,

但是,這種情況總有一天會結束

Triton is being slowed down by Neptune,

海衛一的速度正在被海王星拖慢

and eventually,

直到有一天

it will either crash into it,

它自己也會撞上海王星

or be ground by Neptune's gravity into a huge ring system, similar to Saturn's.

或是被海王星的重力撕裂成一個龐大的行星環,就像土星的一樣

So, don't by real estate on Triton.

所以,千萬別再海衛一上投資房地產

Fixed English Subtiles by Mads Hagemann Nielsen - 2015

Subtitles by the Amara.org community