万物简史 第32期:走进太阳系(10)

 　　Of course we have no prospect¹ of such a journey. A trip of 240,000 miles to the Moon still represents a very big undertaking² for us. A manned mission to Mars, called for by the first President Bush in a moment of passing giddiness, was quietly dropped when someone worked out that it would cost $450 billion and probably result in the deaths of all the crew (their DNA³ torn to tatters by high-energy solar particles from which they could not be shielded).

　　当然，我们没有打算去做这样一次旅行。做一次38.6万公里远的月球旅行，对我们来说依然是一件了不起的大事。老布什总统曾一时头脑发昏，提出要执行一次去火星的载人任务，但后来不了了之。有人估计，这要花费4500亿美元，最后很可能落个全体乘员命归黄泉的结局（他们无法遮挡高能的太阳粒子，DNA会被撕得粉碎）。

　　Based on what we know now and can reasonably imagine, there is absolutely no prospect that any human being will ever visit the edge of our own solar system—ever. It is just too far. As it is, even with the Hubble telescope, we can’t see even into the Oort cloud, so we don’t actually know that it is there. Its existence is probable but entirely⁴ hypothetical.

　　根据我们目前掌握的知识和理智的想像，任何人都绝对不会前往我们自己太阳系的边缘--永远不会。实在太遥远了。事实上，即便使用哈勃望远镜，我们也看不到奥尔特云，因此我们实际上不知道它在哪里。它的存在是可能的，但完全是假设的。

　　Properly called the Opik-Oort cloud, it is named for the Estonian astronomer⁵ Ernst Opik, who hypothesized its existence in 1932, and for the Dutch astronomer Jan Oort, who refined the calculations eighteen years later.

　　也许该称呼它为奥匹克 - 奥尔特云，它是根据爱沙尼亚的天文学家恩斯特·奥匹克命名的，因为是他在1932年发现奥匹克 - 奥尔特云的，同时也是为纪念荷兰天文学家奥尔特扬，因为他18年后细化计算定位了奥匹克 - 奥尔特云。

　　About all that can be said with confidence about the Oort cloud is that it starts somewhere beyond Pluto⁶ and stretches some two light-years out into the cosmos⁷. The basic unit of measure in the solar system is the Astronomical⁸ Unit, or AU, representing the distance from the Sun to the Earth. Pluto is about forty AUs from us, the heart of the Oort cloud about fifty thousand. In a word, it is remote.

　　关于奥尔特云，有把握的只能说到这种程度：它始于冥王星以外，向宇宙里伸展大约两光年。太阳系里的基本计量单位是天文单位（AU），代表太阳和地球之间的平均距离。冥王星距离我们大约40个天文单位，奥尔特云的中心离我们大约5万个天文单位。一句话，它非常遥远。

 

1 prospect   

n.前景，前途；景色，视野

参考例句：

• This state of things holds out a cheerful prospect.事态呈现出可喜的前景。
• The prospect became more evident.前景变得更加明朗了。

2 undertaking   

n.保证，许诺，事业

参考例句：

• He gave her an undertaking that he would pay the money back with in a year.他向她做了一年内还钱的保证。
• He is too timid to venture upon an undertaking.他太胆小，不敢从事任何事业。

3 DNA   

(缩)deoxyribonucleic acid 脱氧核糖核酸

参考例句：

• DNA is stored in the nucleus of a cell.脱氧核糖核酸储存于细胞的细胞核里。
• Gene mutations are alterations in the DNA code.基因突变是指DNA密码的改变。

4 entirely   

ad.全部地，完整地；完全地，彻底地

参考例句：

• The fire was entirely caused by their neglect of duty. 那场火灾完全是由于他们失职而引起的。
• His life was entirely given up to the educational work. 他的一生统统献给了教育工作。

5 astronomer   

n.天文学家

参考例句：

• A new star attracted the notice of the astronomer.新发现的一颗星引起了那位天文学家的注意。
• He is reputed to have been a good astronomer.他以一个优秀的天文学者闻名于世。

6 Pluto   

n.冥王星

参考例句：

• Pluto is the furthest planet from the sun.冥王星是离太阳最远的行星。
• Pluto has an elliptic orbit.冥王星的轨道是椭圆形的。

7 cosmos   

n.宇宙；秩序，和谐

参考例句：

• Our world is but a small part of the cosmos.我们的世界仅仅是宇宙的一小部分而已。
• Is there any other intelligent life elsewhere in the cosmos?在宇宙的其他星球上还存在别的有智慧的生物吗？

8 astronomical   

adj.天文学的，（数字）极大的

参考例句：

• He was an expert on ancient Chinese astronomical literature.他是研究中国古代天文学文献的专家。
• Houses in the village are selling for astronomical prices.乡村的房价正在飙升。