国家地理:送给外星人的地图(7)

Scott's new map is a GPS for the ages. It navigates¹ to Earth using pulsars both inside and outside the Milky² Way, with a twist.

斯考特的新地图是能恒久使用的GPS。它运用银河系以内及以外的脉冲星导航至地球。

Instead of the more ordinary pulsars Dad selected, the new map employs millisecond pulsars that spin faster, last longer, and have also-dead orbital companions. These binary³ pulsars afford a second set of identifiers: the orbital period of the system, which does not change over billions of years. And, crucially, millisecond pulsars age much more slowly than the ones in Dad's map, meaning that it takes thousands of times longer for their spins to become unrecognizable.

与其使用我父亲挑选的那些较普通的脉冲星，这幅新地图运用的是毫秒脉冲星，它们自转得更快，能存在更久，而且有已经死亡的伴星和它们一起在轨道上运行。脉冲星双星提供了第二组辨识特征：这种系统的轨道周期在数十亿年内都不会改变。而且关键在于，毫秒脉冲星的衰老速度远比我父亲地图上的那些脉冲星慢，这意味着在它们的自转失去辨识度以前，历时会比过去的脉冲星多数千倍。

In addition, Scott included another layer of signposts: pulsars in globular clusters orbiting the Milky Way. Ancient clumps⁴ of stars that predate the Milky Way, globular clusters are gorgeous and mysterious, and they are veritable millisecond pulsar factories.

此外，斯考特还查了另一层路标：绕行银河系的球状星团里的脉冲星。球状星团是比银河系更古老的恒星团，既美丽又神秘，而且简直是制造毫秒脉冲星的工厂。

By including signposts in these hard-to-miss stellar globs outside the galaxy⁵, Scott's map allows Earth to be discoverable for billions of years, even after the Milky Way's stars have trekked⁶ around the galactic core multiple times, shuffling⁷ their positions and obliterating⁸ constellations⁹.

一旦有位于明显可见的银河系外球状星团里的路标，无论银河系的恒星绕着银河系核心运行多少圈，改变了它们的位置并导致星座消失，斯考特的地图仍能让地球在未来数十亿年内被找到。

And Dad, for the record, thinks that's spectacular.

另外在此写下以资记录：我父亲认为这想法太棒了。

1 navigates   

v.给（船舶、飞机等）引航，导航( navigate的第三人称单数 )；（从海上、空中等）横越；横渡；飞跃

参考例句：

• Dolpins also navigates by some kind of echo system. 原来海豚也是借助某种回声系统寻向的。 来自辞典例句
• Navigates in menus, lists, choice screens and into edited texts. 可以操纵菜单、列表、屏幕选项和进入编辑文本。 来自互联网

2 milky   

adj.牛奶的，多奶的；乳白色的

参考例句：

• Alexander always has milky coffee at lunchtime.亚历山大总是在午餐时喝掺奶的咖啡。
• I like a hot milky drink at bedtime.我喜欢睡前喝杯热奶饮料。

3 binary   

adj.二，双；二进制的；n.双(体)；联星

参考例句：

• Computers operate using binary numbers.计算机运行运用二进位制。
• Let us try converting the number itself to binary.我们试一试，把这个数本身变成二进制数。

4 clumps   

n.（树、灌木、植物等的）丛、簇( clump的名词复数 )；（土、泥等）团；块；笨重的脚步声v.（树、灌木、植物等的）丛、簇( clump的第三人称单数 )；（土、泥等）团；块；笨重的脚步声

参考例句：

• These plants quickly form dense clumps. 这些植物很快形成了浓密的树丛。 来自《简明英汉词典》
• The bulbs were over. All that remained of them were clumps of brown leaves. 这些鳞茎死了，剩下的只是一丛丛的黃叶子。 来自《简明英汉词典》

5 galaxy   

n.星系；银河系；一群(杰出或著名的人物)

参考例句：

• The earth is one of the planets in the Galaxy.地球是银河系中的星球之一。
• The company has a galaxy of talent.该公司拥有一批优秀的人才。

6 trekked   

v.艰苦跋涉，徒步旅行( trek的过去式和过去分词 )；（尤指在山中）远足，徒步旅行，游山玩水

参考例句：

• They trekked for three days along the banks of the Zambezi. 他们沿着赞比西河河岸跋涉了三天。 来自《简明英汉词典》
• Six-man teams trekked through the woods, respectively for 72 to 96 hours. 6人一组的小分队，经过长途跋涉，穿过了森林，分别用72小时到96小时不等。 来自互联网

7 shuffling   

adj. 慢慢移动的, 滑移的 动词shuffle的现在分词形式

参考例句：

• Don't go shuffling along as if you were dead. 别像个死人似地拖着脚走。 来自英汉文学 - 嘉莉妹妹
• Some one was shuffling by on the sidewalk. 外面的人行道上有人拖着脚走过。 来自英汉文学 - 嘉莉妹妹

8 obliterating   

v.除去( obliterate的现在分词 )；涂去；擦掉；彻底破坏或毁灭

参考例句：

• Michael smoked the competition, obliterating field in most of his events. 迈克尔让比赛放光，几乎淹没了他所参加的大多数项目。 来自互联网
• He heard Pam screaming.The noise became obliterating.Then solid darkness descended. 在一片混乱中，他听到了帕姆的尖叫。接下来，噪音消失了，黑暗降临了。 来自互联网

9 constellations   

n.星座( constellation的名词复数 )；一群杰出人物；一系列（相关的想法、事物）；一群（相关的人）

参考例句：

• The map of the heavens showed all the northern constellations. 这份天体图标明了北半部所有的星座。 来自《简明英汉词典》
• His time was coming, he would move in the constellations of power. 他时来运转，要进入权力中心了。 来自教父部分