康奈爾大學團隊研發純水動力月球軌道衛星
If all goes as planned, a group of U.S. university students will have placed a satellite powered exclusively by water, into orbit around the moon in just over a year.
如果一切都按計劃進行得很順利，一羣美國大學生就可以在一年內將一顆只用水作爲動力的衛星送到月球軌道里。The Cornell University team CisLunar Explorers (cislunar means "between Earth and the moon") and their eponymously named satellite - actually two adjoining satellites - are taking part in a NASA program called the Cube Quest Challenge.
康奈爾大學"地月空間探索者"團隊（"地月空間"的意思是"在地球和月球之間"）和他們的同名衛星--其實是兩顆連在一起的衛星--參加了美國宇航局一項叫作"立方任務挑戰"的項目。The challenge is simple: design, build and deliver "flight-qualified, small satellites capable of advanced operations near and beyond the moon."
挑戰很簡單：設計、製作和發射"具備空間飛行資格、能夠在月球附近和外部進行高級操作的小型衛星"。
Nothing to it, right? Evidently not, because there are 10 teams that are competing in the challenge with names like "Cubequestador" and "Eagles Quest."
這沒什麼難的，是吧？確實如此，因爲有10支名字類似"立方探索"、"飛鷹行動"的隊伍也參加了這項挑戰。But the CisLunar Explorer satellites are unique because the only form of propulsion on board these these two small L-shaped craft is water.
但是"地月空間探索者"衛星是特別的，因爲這兩個小型的L型飛行器的唯一動力就是水。
The idea is the brainchild of Mason Peck who works at Cornell University but used to be NASA's chief technologist. He has always wanted to figure out a way to get beyond rockets as a way to push our spacecraft beyond earth.
這個想法是前美國宇航局首席技術專家、現在在康奈爾大學工作的馬森·派克的創意。他總是想要想出火箭之外的宇宙飛行器動力。"A lot of the mass we send into orbit these days is in the form of rockets – the only way we get anything into space," he said in a Cornell press release.
"這些日子以來，我們送到軌道里的很多東西都是用火箭作爲推進器的--這也是唯一一種推進器。"他在康奈爾大學新聞發佈會上說道。"But what if we could use what's already there? If we could do that, if we could refuel spacecraft while they're already in space..."
"但是如果我們用現成的東西怎麼樣呢？如果我們能做到的話，如果我們能夠給空間裏的飛行器補充燃料的話……"Here's how it works: The craft is two connected satellites that will gradually separate from each other, both shaped like the English letter "L." Water is stored in the lower part of the L.
它的工作原理是這樣的：這兩顆L型衛星是連在一起的，但是會逐漸分開。水儲存在L型的低端。Energy from the sun will electrolyze the water into its two parts, hydrogen and oxygen.
來自太陽的能量將水電解爲氫氣和氧氣。Put the hydrogen, oxygen and a spark together and you get a bang that provides thrust, with water as the only by-product.
氫氣、氧氣和火星在一起會爆炸，產生巨大的能量，而副產品只有水。And it turns out water is pretty plentiful out in space. Icy comets are full of it, and NASA is currently in the process of looking for it on a number of rocky near-earth asteroids.
並且，水在空間裏是相當大量的。冰彗星上全是水，並且現在美國宇航局正在尋找一種全是岩石的近地小行星。The newest theories suggest that most of the water on our planet may have come from asteroids or comets when the ancient Earth was being bombarded with space junk in its formative years.
最新理論表明，我們星球上的大部分水可能是古代地球在形成過程中遭到來自小行星或者彗星的空間垃圾轟擊之後的產物。Another cool thing about the CisLunar Explorer is how the team is teaching it to navigate its way through space.
另一件關於"地月空間探索者"很酷的事是：這個團隊正在調教衛星進行空間自動導航。The idea is to copy how ancient mariners used the moon, sun and stars to fix their position on the oceans.
這個想法是來自於古代航海家利用月亮、太陽和星星的位置來確定自己在海上的位置。Once the twin satellite halves separate after launch they will spin around each other on their way to the moon to keep them from going off course.
在發射之後，兩顆雙子衛星一旦分離，就會在前往月球的路上相互旋轉，防止偏離路線。They will be equipped with cameras and be constantly taking pictures of the sun, Earth and the moon, and comparing their positions and their size.
團隊會給他們裝上攝像機，持續不斷地給太陽、地球和月球拍照，與他們的位置和大小相對比。Based on where the sun, moon and Earth are at any given moment, the CisLunar Explorers will do the math to figure out their position.
基於太陽、月球和地球的實時位置，"地月空間探索者"就可以算出它們的位置。Of the 10 teams competing, the top three winners will hitch a ride on board NASA's space launch system in early 2018.
在10支參賽團隊中，前三名將有機會搭載上美國宇航局2018年初的空間發射系統。The competition is in four stages and the Cornell team has been in the top three in stages one and two.
比賽分爲四個環節，康奈爾大學代表隊在第一和第二環節都是前三名。The winners of this third stage will be announced in about a month, and the final three winners will be announced in early 2017.
第三環節的勝者將在大約一個月之後宣佈，而最終的前三名將在2017年初宣佈。
