今天研究地球生命来源的专家认为

　　on earth today seem to have come to the conclusion

　　海底的高热火山口

　　that the most likely place for life to have begun

　　是最可能开始出现生命的地方

　　is at a hot vent on the ocean floor and we could have

　　木卫二海底的高热火山口附近

　　the same sorts of organisms on the floor of the ocean

　　可能也有

　　of Europa at a hot vent.

　　相同的生物

　　And if you've got bacterial life things

　　如果有像仔菌般的东西

　　then you could have something grazing on the bacteria,

　　就可能有

　　eating the bacteria.

　　以它们为食的生物

　　You could have a whole eco-system down there,

　　那里可能会有一个完整的生态系

　　like sharks grazing on smaller fish and smaller fish

　　好比说大鱼吃小鱼

　　eating worms and the worms eating the bacteria.

　　小鱼吃小虫，小虫吃仔菌一样

　　We, we don't know, there could be all kinds of things there.

　　我们现在还无法确定，但那里可能有各式各样的东西

　　But if, if you want somewhere warm and cosy for bacterial life

　　如果要找一个

　　to get started and to survive,

　　能让仔菌存活的温暖环境

　　Europa is probably the best bet we've got

　　那么木卫二可能是

　　in the entire solar system.

　　全太阳系中最好的选择

　　It wasn'tjust Jupiter's moons that were attracting attention.

　　吸引我们注意力的不只是木星的卫星

　　When the Voyager probe flew past Saturn

　　航海家探测器飞越土星时

　　it captured an image of its largest moon, Titan.

　　拍到了土星最大的卫星，土卫六

　　It was strangely fuzzy.

　　它的影像模糊得令人起疑

　　It looked as though Titan was shrouded in an atmosphere,

　　土卫六似乎被大气层包围

　　just like our own planet.

　　就像地球一样

　　Scientists were desperate to know more.

　　科学家迫切地想知道更多详情

　　What lay beneath this thick atmosphere?

　　这层厚厚大气层下方，有些什么东西？

　　Could it have other similarities to earth?

　　它和地球还有别的相似之处吗？

　　They didn't get their chance to find out

　　又过了20年

　　until twenty years later,

　　卡西尼号升空

　　when Cassini lifted off.

　　这才解答了他们的疑问

　　It was one of the biggest rockets ever launched,

　　那是史上最大的火箭之一

　　but even so it took 7 years to get to Saturn.

　　但尽管如此，卡西尼号还是花了七年才抵达土星

　　And then it turned its attention to Titan.

　　此时卡西尼号将注意力转向土卫六

　　For its party piece Cassini dropped a probe called Huygens

　　卡西尼号发射惠更斯号探测舱

　　through the Titan atmosphere onto the hidden surface.

　　穿过土卫六的大气层降落在土卫六的表面上

　　It revealed a world that scientists believe

　　它拍到的是一个在科学家眼中

　　could be strikingly similar to the early earth.

　　和早期地球相似度极高的世界

　　Pictures that were revealed by Huygens on its parachute

　　惠更斯号在下降至土卫六的表面时

　　descent towards the surface of Titan um showed at one point a,

　　拍到的照片

　　a network of valleys, it could have,

　　显示了一个山谷网络

　　you could have been floating over many parts of the earth.

　　地球上很多地方

　　Where you've got hills and valleys in between them

　　都有相同的山丘和山谷

　　and the valleys converging on one of them and draining into a sea.

　　山谷彼此汇集，然后排入海中

　　So we can see landforms on Titan that look very familiar to people

　　对研究地球地貌的人来说

　　who do landform studies on the earth.

　　土卫六的地貌实在非常眼熟

　　The valley networks are very similar to

　　这些山谷系统和地球上因降雨

　　what you get produced by rainfall on the earth.

　　而形成的山谷系统极为类似

　　The extraordinary images of distant moons

　　探测器自远方卫星回传的惊人照片显示

　　revealed them to be places of great beauty

　　它们不仅美不胜收

　　and tantalising possibilities.

　　而且潜藏着令人心动的可能性

　　They had volcanoes, ice covered oceans,

　　那些卫星上有火山、冰冻海洋

　　active geysers and thick atmospheres.

　　活跃的喷泉和厚厚的大气层

　　There was even the possibility of life.

　　甚至可能有生物

　　Moons were the most exciting places in the solar system.

　　原来太阳系中最有趣的地方竟然是卫星

　　And so scientists began to wonder whether our own

　　科学家开始觉得应该再回过头来看看

　　long abandoned moon was perhaps worth another look.

　　长久以来备受忽视的月球