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  • 2020 may have felt like it lasted forever,

    2020年可能感覺它持續了很久。

  • but it was actually the shortest year in decades.

    但它實際上是幾十年來最短的一年。

  • In fact, it was 1.3 milliseconds shorter.

    事實上,它縮短了1.3毫秒。

  • The planet is now spinning faster than it has any time in the last half-century,

    地球現在的旋轉速度比過去半個世紀中的任何時候都快。

  • with 2020 containing 28 of the fastest days on record since 1960.

    2020年包含了自1960年以來記錄中最快的28天。

  • And 2021 is expected to be even faster...

    而2021年預計會更快...。

  • which has ignited a fiery debate about what we should do to keep the world on track.

    這引發了一場關於我們應該怎樣做才能讓世界走上正軌的火熱辯論。

  • It may sound weird, but shifts in a planet's spin are actually normal.

    這聽起來可能很奇怪,但行星自旋的轉變實際上是正常的。

  • Things like the pull of the moon,

    像月亮的拉力這樣的事情。

  • jet stream winds,

    噴氣流的風。

  • and plate tectonics all have an effect.

    和板塊構造學都有影響。

  • Just like an ice skater draws in their arms to spin faster,

    就像滑冰者為了更快地旋轉而抽出手臂一樣。

  • anything that moves mass closer to Earth's axis speeds up the planet's spin,

    任何使品質靠近地球軸線的東西都會加速地球的旋轉。

  • making the days a few milliseconds shorter.

    使得日子短了幾毫秒。

  • It doesn't seem like much, but these subtle changes in Earth's spin

    這看起來並不多,但地球自旋的這些微妙變化

  • can cause major headaches for anyone trying to keep their clocks in sync.

    可能會給任何試圖保持時鐘同步的人帶來很大的麻煩。

  • But first, here's a little context on how our timekeeping has evolved.

    但首先,這裡有一個關於我們的記時法如何演變的小背景。

  • Before we had cell phones, computers, or GPS to tell time, we had the Sun.

    在我們有手機、電腦或GPS來顯示時間之前,我們有太陽。

  • Ancient civilizations measured time using Earth's rotation relative to the sun

    古代文明利用地球相對於太陽的旋轉來測量時間

  • with devices like sundials.

    與日晷等設備。

  • We know this today as solar time.

    我們今天知道這就是太陽時。

  • Around 150 AD, Ptolemy divided Earth's 360 degrees of latitude and longitude

    公元150年左右,托勒密劃分了地球的360度經緯度

  • into 60 equal parts, into thefirst minute”, and then again, into a “second minute”, the basis for a second.

    抽成60個相等的部分,變成 "第一分鐘",然後再變成 "第二分鐘",這是一秒鐘的基礎。

  • The development of quartz clocks in the 1930's made timekeeping even more precise,

    20世紀30年代,石英鐘的發展使計時更加精確。

  • and for the first time allowed us to measure variations in Earth's rotation.

    並首次使我們能夠測量地球旋轉的變化。

  • Then atomic clocks revolutionized timekeeping.

    然後,原子鐘徹底改變了計時方式。

  • In 1955, the National Physics Laboratory in England built the first accurate cesium clock,

    1955年,英國的國家物理實驗室建造了第一個精確的銫鐘。

  • and twelve years later, the General Conference on Weights and Measures redefined the second,

    而12年後,計量大會重新定義了第二種。

  • based on this crazy number of oscillations of a cesium atom.

    基於一個銫原子的這種瘋狂的振盪次數。

  • This ultra-precise definition of a second is the foundation of International Atomic Time,

    這種對一秒鐘的超精確定義是國際原子時的基礎。

  • the average of hundreds of atomic clocks worldwide, making it our most accurate time keeper.

    是全世界數百個原子鐘的平均數,使其成為我們最精確的時間記錄器。

  • Atomic time can measure the spin of the planet down to the millisecond.

    原子時間可以測量行星的旋轉,精確到毫秒。

  • But the increase in accuracy comes with a downside.

    但是準確度的提高也有一個缺點。

  • Since atomic time ticks away at an incredibly constant rate,

    由於原子時間以驚人的恆定速度流逝。

  • it doesn't slow-down or speed-up with the spin of the Earth.

    它不會隨著地球的旋轉而減慢或加快。

  • So, over the years atomic time has slowly drifted out of sync with the fluctuations of the planet.

    是以,多年來,原子時間已經慢慢地與地球的波動不同步了。

  • Whenever the difference between solar time and atomic time

    每當太陽時和原子時之間的差異

  • threatens to exceed 0.9 seconds,

    有可能超過0.9秒。

  • a leap second gets added to Coordinated Universal Time to make up for the difference.

    閏秒被添加到協調世界時中,以彌補差異。

  • UTC is kept using atomic clocks, but with all those leap seconds added in.

    UTC是使用原子鐘來保持的,但加入了所有這些閏秒。

  • To date, we've added 27 leap seconds since 1972.

    到目前為止,自1972年以來,我們已經增加了27個閏秒。

  • The extra second gets squeezed in at midnight UTC.

    多出的一秒在UTC午夜時分被擠了進去。

  • Which is where the heated debate comes in.

    這就是激烈辯論的地方。

  • Those who want to abolish the leap second say that in addition to being cumbersome,

    那些想廢除閏秒的人說,除了繁瑣之外。

  • it would take 5,000 years to notice even a one hour difference

    即使是一小時的差異,也需要5000年才能注意到

  • between Earth's rotation and the atomic clock.

    地球的自轉和原子鐘之間的關係。

  • And when one was added in 2012,

    而當2012年增加了一個。

  • the reservation system used by Qantas airlines collapsed,

    澳大利亞航空公司使用的預訂系統崩潰。

  • and several websites including Reddit, Mozilla, and Gawker,

    和一些網站,包括Reddit、Mozilla和Gawker。

  • crashed when their systems failed to handle the extra second.

    當他們的系統無法處理額外的一秒鐘時,就會崩潰。

  • However, those in favor of the leap second argue that the technical issues are overblown.

    然而,支持閏秒的人認為,技術問題被誇大了。

  • Just a few years later in 2015, another second was added

    就在幾年後的2015年,又增加了第二個--

  • and there were only a few minor hiccups.

    而且只出現了一些小插曲。

  • The standoff is real and countries have already taken sides,

    對峙是真實的,各國已經站在了一邊。

  • with the U.K. and Russia in favor of keeping leap seconds,

    與英國和俄羅斯一樣,贊成保留閏秒。

  • and countries like the U.S. and China advocating their drop.

    以及像美國和中國這樣的國家主張他們放棄。

  • At the 2015 World Radiocommunication Conference held by the U.N.,

    在聯合國舉行的2015年世界無線電通信大會上。

  • countries couldn't come to an agreement,

    各國無法達成協議。

  • so they decided to put off their decision till their next conference in 2023.

    所以他們決定將決定延後到2023年的下一次會議。

  • But no matter how long they debate, the Earth will continue to spin.

    但無論他們辯論多久,地球都會繼續旋轉。

  • And it's up to the International Earth Rotation and Reference Systems Service, or IERS,

    而這取決於國際地球自轉和參考系統服務,或IERS。

  • to determine if a year needs a leap second or not.

    來確定一個年份是否需要一個閏秒。

  • Last year Earth's rotation was fast,

    去年,地球的自轉速度很快。

  • and didn't need a leap secondat least, in the traditional sense.

    而且不需要躍進的第二步--至少,在傳統意義上。

  • Because it was spinning so fast,

    因為它轉得太快了。

  • the average day was estimated to be .05 milliseconds shorter than a typical 24-hour period.

    據估計,平均每天比典型的24小時內短0.05毫秒。

  • Because of this, the group considered something they never had before: adding a negative leap second.

    正因為如此,該小組考慮了他們以前從未考慮過的問題:增加一個負的閏秒。

  • Instead of gaining a second, we would lose one.

    我們非但沒有獲得一秒鐘,反而會失去一秒鐘。

  • And this year, scientists expect it to be even speedier!

    而在今年,科學家們預計它的速度會更快!

  • While the group ultimately decided not to add this negative leap second last year,

    雖然該小組去年最終決定不增加這個負數的閏年。

  • it's possible that they might have to when they meet again this June.

    他們有可能在今年6月再次見面時不得不這樣做。

  • All I know is when they finally make a decision,

    我所知道的是當他們最終做出決定時。

  • we'll all be saying, it's about time.

    我們都會說,是時候了。

  • We talked about removing a second from our clocks, but what about time itself?

    我們談到了從我們的時鐘中刪除一秒,但時間本身呢?

  • Can it ever run backward?

    它能不能向後運行?

  • Check out this video from Julian that explains how time might not reverse like physicists thought.

    看看這個來自朱利安的視頻,它解釋了時間可能不像物理學家所想的那樣逆轉。

  • Have some cool science you'd like to see us cover?

    有一些你想看到我們報道的很酷的科學嗎?

  • Let us know in the comments below and as always, thanks for watching Seeker.

    請在下面的評論中告訴我們,並一如既往地感謝觀看《探索者》。

2020 may have felt like it lasted forever,

2020年可能感覺它持續了很久。

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B1 中級 中文 地球 原子 增加 時間 速度 辯論

科學家們正在與時間和地球自轉進行競賽 (Scientists Are in a Race Against Time and Earth’s Rotation)

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    Summer 發佈於 2021 年 06 月 30 日
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