万物简史 第349期:孤独的行星(14)

The figures have since been refined and made a little more generous, 自那以后，这两个数字被更精确地测算了一遍，放宽了一点， 5 percent nearer and 15 percent farther are thought to be more accurate assessments for our zone of

万物简史 第350期:孤独的行星(15)

Its surface temperature is a roasting 470 degrees centigrade (roughly 900 degrees Fahrenheit), which is hot enough to melt lead, 它的表面温度高达470摄氏度，连铅都会熔化。 and the atmospheric pressure at the surface is ninety times

万物简史 第351期:孤独的行星(16)

Apart from much else, our lively interior created the outgassing that helped to build an atmosphere 不说别的，我们活跃的内部使大量气体喷涌而出，帮助建立了大气层， and provided us with the magnetic field that shields us

万物简史 第352期:孤独的行星(17)

The Moon's steady gravitational influence keeps the Earth spinning at the right speed and angle 由于月球持久的引力影响，地球能以合适的速度、合适的角度自转， to provide the sort of stability necessary for the long and suc

万物简史 第353期:孤独的行星(18)

We don't really know for sure because we have nothing else to compare our own existence to, 我们确实不知道，因为我们没有任何别的东西可以用来跟我们自己的存在进行比较。 but it seems evident that if you wish to end u

万物简史 第354期:孤独的行星(19)

As you might expect, oxygen is our most abundant element, accounting for just under 50 percent of the Earth's crust, 你也许会想到，氧是最丰富的元素，占地壳的将近50%。 but after that the relative abundances are often surprising.

万物简史 第355期:孤独的行星(20)

Nor does abundance necessarily relate to importance. 风度与重要程度也不一定有关系。 Carbon is only the fifteenth most common element, accounting for a very modest 0.048 percent of Earth's crust, but we would be lost without it. 碳只居

万物简史 第356期:孤独的行星(21)

We have evolved to utilize or tolerate these thingswe could hardly be here otherwise but even then we live within narrow ranges of acceptance. 我们已经逐步学会利用或忍受这些东西要不然我们几乎不可能在这里但即使那样，我

万物简史 第358期:孤独的行星(23)

The Romans also flavored their wine with lead, which may be part of the reason they are not the force they used to be. 罗马人也用铅来给酒调味，这也许是他们不再像以往那样强大的部分原因。 As we have seen elsewhere, our

万物简史 第359期:孤独的行星(24)

Any visitors to Earth from afar would almost certainly, at the very least, be bemused to find us living in an atmosphere composed of nitrogen, 任何光临地球的远方客人几乎肯定都会觉得好笑，发现我们生活在一种由氮和氧组成

万物简史 第360期:进入对流层(1)

17 Into the Troposphere 第十七章 进入对流层 Thank goodness for the atmosphere. It keeps us warm. 谢天谢地，我们有了大气。它使我们有了个温暖的环境。 Without it, Earth would be a lifeless ball of ice with an average te

万物简史 第361期:进入对流层(2)

From ground level to its highest point, the troposphere (or turning sphere) 从地面到最高点，对流层（亦称对流圈） is about ten miles thick at the equator and no more than six or seven miles high in the temperate latitudes where most

万物简史 第362期:进入对流层(3)

The temperature six miles up can be -70 degrees Fahrenheit, and you would need, or at least very much appreciate, supplementary oxygen. 10公里高空的温度会降至零下57摄氏度，你需要补充氧气，至少很希望这么做。 After you

万物简史 第363期:进入对流层(4)

Even so, spaceships have to take care in the outer atmosphere, particularly on return trips to Earth, 即使这样，宇宙飞船在外层大气也不得不小心翼翼，尤其是在重返地球的过程中。 as the space shuttle Columbia demonstra

万物简史 第357期:孤独的行星(22)

Oxygen itself is not combustible; it merely facilitates the combus tion of other things. （氧本身是不可燃的，它只是帮助别的东西燃烧。 This is just as well, for if oxygen were corn bustible, each time you lit a match all the air

万物简史 第373期:进入对流层(14)

However, for reasons unknown he calibrated the instrument in a way that put freezing at 32 degrees and boiling at 212 degrees. From the outset this numeric eccentricity bothered some people, and in 1742 Anders Celsius, a Swedish astronomer, came up w

万物简史 第378期:进入对流层(19)

What happens is that surface waters, as they get to the vicinity of Europe, 情况是这样的：表面海水抵达欧洲附近以后， grow dense and sink to great depths and begin a slow trip back to the southern hemisphere. 密度增加，沉到深

万物简史 第377期:进入对流层(18)

Oceans are the real powerhouse of the planet's surface behavior. 海洋是地球表面活动的真正动力源泉。 Indeed, meteorologists increasingly treat oceans and atmosphere as a single system, which is why we must give them a little of our at

万物简史 第376期:进入对流层(17)

When you look at a lake, you are looking at a collection of molecules that have been there on average for about a decade. 要是你望一眼湖水，你看到的是一大堆分子，它们在那里平均已达10年之久。 In the ocean the residence

万物简史 第375期:进入对流层(16)

Any water molecule that strays beyond the edge of the cloud is immediately zapped by the dry air beyond, allowing the cloud to keep its fine edge. 要是水分子越出该云边缘，外面干燥的空气马上会把它除掉，从而使积云的边缘