The moon is moving away from Earth and this is making days longer
月亮离地球越来越远，这让一天的时间更长
We sometimes wish days were longer to fit our busy schedules. Luckily, someone up there is listening. No, it’s not some all-powerful deity — I’m referring to our conspicuous, friendly celestial neighbor, the moon. According to a landmark study, a day on Earth lasted only 18 hours about 1.4 billion years ago. As the moon slowly drifts away from Earth, its influence on our planet’s spin around its axis is waning, thereby making days last longer
我们有时希望一天能长一些，以满足我们忙碌的时间表。幸好苍天有耳，听到了我们的祈求。当然不是了，我说的不是什么全能的神 - 而是显而易见的、我们的友好太空邻居、月亮。根据一项划时代的研究，大约14亿年前，地球上一天的长度只有18小时。在月亮慢慢地离开地球漂走的过程中，它对我们的行星绕轴旋转的影响也在减弱，从而使一天的时间变得更长。
deity ： [ˈdiɪti] n. 上帝;神，女神
conspicuous：[kənˈspɪkjuəs] adj. 明显的;显而易见的;惹人注意的;显目
celestial： [səˈlestʃl] adj. 天的，天空的
wane：[wɑ:n] 衰弱
“As the moon moves away, the Earth is like a spinning figure skater who slows down as they stretch their arms out,” explains Stephen Meyers, professor of geoscience at the University of Wisconsin-Madison and co-author of the new study published in the Proceedings of the National Academy of Sciences.
“在月亮离开地球时，地球就像一个正在旋转的花样滑冰运动员一样，当他们伸出双臂时，旋转速度就逐渐慢了下来，” 威斯康星大学麦迪逊分校的地球科学教授Stephen Meyers在《国家科学院院刊》发表的一项他与人合写的新的研究中做了这样的解释。
Every year, the moon drifts away from Earth at the rate of 3.78cm (1.48in) per year, or at about the same speed at which our fingernails grow. The migration of the Moon away from the Earth is mainly due to the action of the Earth’s tides.
年复一年，月亮都以每年 3.78cm (1.48in) 的速度向地球外漂移，这个速度大约和我们的指甲生长的速度一样。月球游离地球的主要原因是地球潮汐的作用。
migration: [maɪˈɡreʃən] n. 迁移，移居
Without the moon, Earth could slow down enough to become unstable, but this would take billions of years and it may never happen at all.
没有月亮的话，地球的自转速度可能会慢到使其变得不稳定，但这或许需要亿万年的时间，而且或许也永远不会发生。
Scientists believe that when Earth and the moon were barely formed some 4.5 billion years ago, days were only five hours long. As the satellite drifted farther away from Earth, days grew longer and this is traceable in the fossil records of some creatures. For instance, the daily growth bands of corals record the number of days that occurred per year in ancient times. By one estimate, days are getting longer at a rate of 19 hours every 4.5 bn years.
科学家们认为，当地球和月球在45亿年前刚刚形成时，一天的时间只有五个小时长。当这个卫星逐渐的离开地球，天也变得长了，这在一些生物的化石记录中是有迹可循的。例如，珊瑚的每日生长带就记录了远古时代每年的天数。根据一项估计，一天的长度在以每45亿年19小时的速度在增加。
Now, using a new method, Meyers and colleagues were able to devise a novel way to calculate the moon’s influence on the days on Earth.
现在， Meyers和他的同事们设计出一种奇特的方法，用以来计算月球对地球上的天数的影响。
novel：[ˈnɑ:vl]adj. 新奇的;异常的
Using such an approach, Meyers and colleagues assessed variations in Earth’s axis of rotation both in more recent and earlier times, while also addressing uncertainty. This is how they were able to determine the length of the day, and also the distance between Earth and the moon, for various periods.
使用这种方法，Meyers和同事们评估了地球自转轴在最近和更早时期的变化，同时也探究处理它的不稳定性。他们就是用此方法确定了在不同的时期，一天的长度，以及地球和月球之间的距离。
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