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  • You may have heard that Mars doesn't have a magnetic field. But that's not true!

    你可能聽說過,火星沒有磁場。但這不是真的!

  • Now, thanks to data from NASA's MAVEN satellite,

    現在,由於美國宇航局MAVEN衛星的數據。

  • researchers at the University of Colorado, Boulder

    科羅拉多大學博爾德分校的研究人員。

  • have created the very first detailed map of the electric currents responsible for shaping

    繪製了第一張詳細的電流圖,該圖負責塑造

  • the magnetic field that wraps around Mars.

    圍繞火星的磁場。

  • Not only are the visualizations stunning,

    不僅視覺效果驚人。

  • but they provide clues of how we can make this inhospitable planet one we can live on...maybe.

    但它們提供了線索,告訴我們如何讓這個荒涼的星球成為我們可以生活的地方......也許。

  • Let's start with what we know so far. The region of space around a planet that's

    讓我們從目前所知的情況開始。一個星球周圍的空間區域是:

  • dominated by that planet's magnetic field is known as its magnetosphere.

    由該行星的磁場所主導,稱為其磁層。

  • Earth's magnetosphere is driven by an internal dynamo,

    地球的磁層是由內部的發電機驅動的。

  • a rotating mass of molten iron that's located in our planet's outer core.

    一團旋轉的熔融鐵,位於我們星球的外核。

  • The energy generated by the rising, cooling, and sinking of that molten iron

    那塊熔鐵的上升、冷卻和下沉所產生的能量。

  • gets converted into a powerful magnetic fieldwhich shields Earth from

    轉化為強大的磁場,保護地球不受汙染。

  • the charged particles of solar and cosmic radiation and protects our atmosphere.

    太陽和宇宙輻射的帶電粒子,保護我們的大氣層。

  • Unlike Earth, Mars doesn't have a dynamoand as a result, no intrinsic magnetic field

    與地球不同的是,火星沒有發電機--是以,也沒有內在的磁場

  • to stop charged particles from stripping away its atmosphere.

    以阻止帶電粒子剝離其大氣層。

  • But this wasn't always the case.

    但情況並非總是如此。

  • Turn back the clock to about 4.3 billion years ago and Mars might have looked a lot more Earth-like.

    把時間撥回到大約43億年前,火星可能看起來更像地球。

  • It had a thick atmosphere and warm climate

    它有濃厚的氣氛和溫暖的氣候

  • capable of sustaining bodies of water like rivers, lakes, and even oceans!

    能夠養活江河湖泊甚至海洋等水體!

  • All of this would have been possible if Mars once had a working dynamo of its own to protect its atmosphere.

    如果火星曾經有一個自己工作的發電機來保護它的大氣層,這一切都會成為可能。

  • But somehow, Mars transformed from a warm and wet place

    但不知怎的,火星從一個溫暖潮溼的地方變成了

  • into a cold, inhospitable desert.

    變成了一片寒冷、荒涼的沙漠。

  • There are a couple of leading theories as to what might have caused this dramatic transformation.

    關於是什麼原因導致了這種戲劇性的轉變,有幾種主要的理論。

  • Some scientists believe that a series of giant asteroid impacts bombarded Mars over a period

    一些科學家認為,在一段時期內,一系列巨大的小行星撞擊轟擊了火星。

  • of 100 million years. The idea goes that these impacts overheated the planet's mantle

    一億年的時間認為這些撞擊使地球的地幔過熱了

  • and stopped the dynamo, effectively killing off the planet's intrinsic magnetic field.

    並停止了發電機,有效地殺死了地球的固有磁場。

  • Certain evidence suggests that Mars might have had a dynamo in only a single hemisphere.

    某些證據表明,火星可能只在一個半球有一個發電機。

  • And in fact, missions to the red planet have found remnants of a stronger magnetic field

    而事實上,前往紅色星球的任務已經發現了更強的磁場的殘餘物

  • in its southern hemisphere.

    在其南半球。

  • With a lopsided energy field, the planet's atmosphere

    隨著能量場的傾斜,行星的大氣層也在發生變化

  • would have been left vulnerable to erosion from the solar wind,

    就會容易受到太陽風的侵蝕。

  • allowing it to collide with atoms in the upper atmosphere and eject them into space through a process

    讓它與高層大氣中的原子相撞,並通過一個過程將它們彈射到太空。

  • calledsputtering.”

    稱為 "濺射"。

  • As its atmospheric gas was slowly stripped away,

    隨著其大氣中的氣體被慢慢剝離。

  • Mars' atmosphere eventually became depleted enough to transform the planet into a cold, arid place.

    火星的大氣層最終變得枯竭,足以讓這個星球變成一個寒冷、乾旱的地方。

  • Today, signs of Mars' ancient intrinsic magnetic field still exist.

    如今,火星古老的固有磁場的跡象依然存在。

  • Since 2018, NASA's InSight lander has been on the ground measuring the strength and direction

    自2018年以來,NASA的InSight著陸器一直在地面上測量強度和方向。

  • of the planet's magnetic field and collecting detailed measurements of magnetic fields in the crust.

    的行星磁場,並收集地殼中磁場的詳細測量結果。

  • Because most of the rocks at Mars' surface

    因為火星表面的大部分岩石

  • are too young to have been magnetized by the planet's former field, scientists speculate

    科學家們推測,由於太過年輕,不可能被星球以前的磁場磁化。

  • that the sources of these crustal magnetic fields are rocks buried deep underground.

    這些地殼磁場的來源是埋在地下深處的岩石。

  • Located anywhere from a couple of hundred meters to several kilometers below the ground,

    位於地下幾百米到幾公里的地方。

  • these older rocks formed before the planet's dynamo shut down and remain magnetized,

    這些較老的岩石形成於行星的發電機關閉之前,並保持磁化。

  • acting as local mini-magnetospheres today.

    作為今天的局部小磁層。

  • By combining the measurements collected by InSight with satellite data,

    通過將InSight收集的測量數據與衛星數據相結合。

  • researchers hope to identify exactly which rocks carry magnetism

    研究人員希望能確定到底是哪些岩石帶有磁性

  • and figure out how old they are.

    並計算出他們的年齡。

  • While on the ground, InSight has also recorded

    在地面上,InSight還記錄了:

  • mysterious fluctuations in the strength and direction of the magnetic field between day and night.

    晝夜之間磁場強度和方向的神祕波動。

  • Here's how it worksThe charged particles that make up the solar wind are

    下面是它的工作原理。組成太陽風的帶電粒子是:

  • highly conductive, inducing electric currents that shape how energy flows into Mars' atmosphere.

    高導電性,誘發電流,形成能量如何流入火星的大氣層。

  • These currents cause a 'pile-up' of the magnetic field in the planet's upper atmosphere,

    這些電流會導致地球上層大氣的磁場 "堆積"。

  • until they become strong enough to create an induced magnetosphere.

    直到它們強大到足以形成一個誘導磁層。

  • By analyzing five years of data from MAVEN, researchers were able to piece together the

    通過分析MAVEN五年來的數據,研究人員能夠拼湊出MAVEN的數據。

  • electric current systems in Mars' atmosphere.

    火星大氣中的電流系統。

  • The initial results show how these electric currents

    初步結果顯示,這些電流是如何產生的?

  • interact with the solar wind, causing it to wrap around the planet and form an induced

    與太陽風相互作用,使其環繞地球,形成誘導的

  • magnetosphere that offers Mars some protection.

    磁層,為火星提供一定的保護。

  • Because while MAVEN and other previous missions

    因為雖然MAVEN和其他以前的任務

  • have seen hints of these currents before, this is the first time we've been able to map the complete circuit.

    之前已經看到了這些電流的提示,這是我們第一次能夠繪製完整的電路。

  • MAVEN's goal is to explore the upper atmosphere,

    MAVEN的目標是探索高層大氣。

  • and it's not aloneAlong with five other current Mars missions,

    而且它並不孤單。隨著目前其他五個火星任務。

  • it's trying to understand the potential for life to exist on Mars.

    它試圖瞭解生命在火星上存在的可能性。

  • If we ever plan to put boots down on the red planet,

    如果我們打算在紅色星球上放下靴子。

  • we'll need to understand how important a magnetic field is for regulating climate.

    我們需要了解磁場對調節氣候有多重要。

  • Because while this work won't bring back Mars' thick atmosphere,

    因為雖然這項工作不會讓火星的濃厚大氣層重現。

  • it may help us determine if Mars ever hosted life and if it could again.

    它可能會幫助我們確定火星是否曾經有生命存在,以及是否會再次出現。

  • Mars isn't the only misfit without an intrinsic magnetic field.

    火星並不是唯一一個沒有固有磁場的不適應者。

  • Venus doesn't have one either!

    金星也沒有!

  • If you wish you had an interplanetary zip code of your own,

    如果你希望自己有一個屬於自己的星際郵編。

  • why not check out this video on terraforming Venus and Mars!

    為什麼不看看這個關於金星和火星梯田化的視頻呢?

  • Is there any cool space phenomena you'd like to see us cover?

    有什麼酷炫的太空現象你想看到我們報道嗎?

  • Let us know down in the comments below.

    讓我們在下面的評論中知道下來。

  • Make sure to subscribe and thanks so much for watching.

    一定要訂閱,非常感謝您的觀看。

You may have heard that Mars doesn't have a magnetic field. But that's not true!

你可能聽說過,火星沒有磁場。但這不是真的!

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