Mars has two moons, Phobos and Deimos.

火星有兩顆衛星，火衛一(福波斯)和火衛二(戴摩斯)。

They are really tiny. How tiny?

他們是真的很渺小。那有多渺小？

Compared to Mars or our own Moon,

對比火星或我們自己的月亮，

pretty tiny.

非常的渺小。

Although ‘tiny’ is a matter of opinion.

不過算不算上渺小，還是見仁見智。

Their surface area is up close to some of the smallest states on Earth,

它們的表面面積，接近地球上一些比較小的國家，

like Luxembourg and Malta.

例如盧森堡和馬耳他。

Although Phobos and Deimos are in no way lightweight,

雖然火衛一和火衛二，算不上十分輕量化，

in reality, their gravitational pull isn't even strong enough

但在現實中它們的引力，仍然沒有強大到足以使它們變為球形。

to bring them into spherical form.

因此，他們看起來更像巨大的土豆，多於月亮。

So they look more like huge potatoes than moons.

它們的起源最流行的理論是，他們曾經是小行星帶的一部分

The most popular theory of their origin

直到被木星巨大的驅趕出來。

is that they were once part of the asteroid belt,

因此，讓火星能捕捉到它們。

until Jupiter's massive gravity kicked them out of it,

火衛一的軌道，距離火星9,400公里，平均每7個半小時環繞火星一次。

so Mars could catch them.

在運行的過程中，它以每年2米的速度接近火星。

Phobos orbits Mars at a average distance of 9,400 kilometres, once every 7½ hours.

在50到100萬年內，它要不是被火星的重力撕得粉碎，(潮汐力)

It's on a collision course, and gets 2 metres closer to Mars every year.

而轉化成一個​​漂亮的環，

In 50 to 100 million years, it will either be ripped to pieces by Mars’ gravity

不然就是直接撞上火星。

and be transformed into a beautiful ring,

撞擊的能量足以摧毀這小星球(火星)上所有的一切。

or it will crash into Mars.

所以，如果有火星人話，他們就應該要建設非常堅固的掩體。(笑)

The energy released in this collision would kill everything on the small planet.

另一方面，較小的火衛二，正緩慢的遠離火星。

So, if there are humans on Mars by then, they should build very strong bunkers.

最終，它會飛走進入太空，並留下一個孤獨的紅色星球。

Smaller Deimos, on the other hand, is slowly escaping Mars.

因此，在幾百萬年後，火星將沒有衛星，只剩下它自己。

Eventually, it will fly off into space and leave a lonely red planet behind.

除非，它再一次捕捉到另一個新的小行星。

So, in a few hundred million years, Mars will be moonless and on its own.

繁體中文字幕由Sheldonng

Unless it manages to catch itself another asteroid.

Subtitles by the Amara.org community