The search for life beyond Earth begins with understanding life on our home planet. And that story, the story of life on Earth, may have begun in our oceans. And that's because, of course, if we've learned anything about life on Earth, it's that where you find the liquid water, you generally find life.
在地球以外生命的探索從了解在我們母星上的生命開始。而那故事－－地球上生命的故事－－可能始於我們的海洋。而那是因為，想當然爾，如果我們有學到關於地球上生命的任何事，那就是你在哪找到液態水，你大致上就找到生命了。
So, what if I told you that there is an ocean out there beyond Earth? An ocean in our solar system that has been in existence for billions of years, it's an ocean that is perhaps 10 times as deep as Earth's ocean. It's an ocean that is global and may contain two to three times the volume of all the liquid water on the earth. It's an ocean that exists beneath the icy shell of Jupiter's moon—Europa.
那麼，如果我告訴你在地球之外有一片海洋呢？一片在我們的太陽系中存在數十億年的海洋，那是一片可能是地球海洋十倍深的海洋。那是片遍布星球，而且可能含有地球上所有液態水量二到三倍的海洋。那是片存在於木星的衛星其冰殼之下的海洋－－也就是木衛二。
So how do we think we know that Europa's ocean exists? Well, it's a combination of using telescopes on the ground, and having spacecraft that have flown by Europa and collected data about the surface, about the interior structure, and about the magnetic field around Europa. And the combination of those data sets leads us to a high degree of confidence that this global liquid water H2O ocean is there today, and it's been there for much of the history of the solar system.
我們如何認定我們知道木衛二的海洋存在呢？嗯，這是個利用地面望遠鏡，且派出飛掠木衛二並收集關於表面、關於內部結構，以及木衛二周圍磁場數據的飛船的結合。而那些數據組的結合使我們有高度信心確定這個遍布星球的液態水 H2O 海洋目前在那裡，而且在太陽系大部分的歷史中它就在那了。
We used to think that in order for a world to be habitable, you had to be at just the right distance from the sun or whatever your star was such that you could have a liquid water ocean on the surface. Now along with liquid water, life as we know it needs two other key stones.
我們過去常以為要使一個天體適合居住，你必須要在離太陽或任何你的恆星恰好正確的距離，如此一來你才能在表面上擁有液態水海洋。現在除了液態水外，我們所知的生命還需要另外兩樣關鍵基石。
The first is the building blocks for life, the stuff you find in rocks, and the second is some form of energy to help power life. And here's where Europa is a real game changer. It is far, far out from the sun, and yet it's got this liquid water ocean. And the reason that Europa has liquid water is because it's orbiting Jupiter, and the tidal tug and pull causes Europa to flex up and down, and all that tidal energy turns into mechanical energy, which turns into friction and heat that helps maintain this liquid water ocean beneath an icy shell.
第一樣是生命的基本要素，也就是你在岩石內找到的東西，而第二樣是幫助提供生命動力的某種型態的能量。而這就是木衛二是個真正變革角色的地方。它離太陽非常、非常遙遠，然而它卻有這液態水海洋。木衛二有液態水的原因是因為它繞著木星運行，而那潮汐的拖和拉力使得木衛二來回伸縮，那潮汐力轉變成機械能，機械能轉變為幫助維持冰殼下液態水海洋的摩擦力和熱能。
Along with helping maintain liquid water, we think that tidal energy may also allow that ocean to interact with rocks on Europa's sea floor, and it may even give rise to things like hydrothermal vents, which could help provide not just the building blocks for life, but also the energy for life.
除了協助維持液態水型態外，我們認為那種潮汐力可能也使得那海洋能夠和在木衛二海床上的岩石互相作用，而這甚至可能產生像是深海溫泉的事物，那可以協助提供不僅生命的基本要素，還有生命的能量。
The question of whether or not life exists beyond Earth, the question of whether or not biology works beyond our home planet, is one of humanity's oldest and yet unanswered questions. And for the first time in the history of humanity, we have the tools and technology and capability to potentially answer this question. And, we know where to go to find it—Jupiter's ocean world, Europa.
生命是否存在地球以外的問題、生物在我們的母星外是否能行得通的問題，是人類最古老然而未解答的問題之一。而人類史上頭一回，我們有工具和技術和能耐有機會能去回答這個問題。而且，我們知道要去哪裡找答案－－木星的海洋世界，木衛二。
- 「除了某事物外」- Along With
Now along with liquid water, life as we know it needs two other key stones.
現在除了液態水外，我們所知的生命還需要另外兩樣關鍵基石。 - 「產生、引起」- Give Rise To
...we think that tidal energy may also allow that ocean to interact with rocks on Europa's sea floor, and it may even give rise to things like hydrothermal vents...
...我們認為那種潮汐力可能也使得那海洋能夠和在木衛二海床上的岩石互相作用，而這甚至可能產生像是深海溫泉的事物...
