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  • On the list of all-time big picture questions, “Where did we come from?' has got to be near the top.

    在所有的大圖片問題的列表中,"我們從哪裡來?"一定是接近頂部。

  • It's stumped philosophers and scientists since the beginning of philosophy and science.

    自哲學和科學誕生以來,它就一直困擾著哲學家和科學家。

  • Now though, one spacecraft, OSIRIS-REx, is going to take a run at answering this monumental question...

    現在,有一個航天器,OSIRIS-REX,要回答這個巨大的問題... ...

  • by attempting to collect a sample of our early solar system from an asteroid.

    試圖從一顆小行星上收集我們早期太陽系的樣本。

  • NASA's Origins, Spectral Interpretation, Resource Identification, and Security-Regolith Explorer,

    美國宇航局的起源、光譜解讀、資源識別和安全-巨石探測器。

  • or OSIRIS-REx, was launched in September of 2016

    或OSIRIS-REx,於2016年9月發射。

  • with the goal of collecting samples from an asteroid.

    目的是收集小行星的樣本。

  • But not just any asteroidspecifically, NASA was interested in sampling a rare B-type asteroid.

    但不是任何一顆小行星--具體來說,NASA對一顆罕見的B型小行星取樣很感興趣。

  • B-type asteroids are primitive, meaning they haven't changed much since the Earth was formed 4.5 billion years ago.

    B型小行星是原始的,也就是說,自從地球在45億年前形成以來,它們並沒有什麼變化。

  • This could mean they contain carbon-based organic molecules similar to those that led to life on Earth.

    這可能意味著它們含有類似於導致地球生命的碳基有機分子。

  • The specific B-type asteroid OSIRIS-REx was shot at was called 1999 RQ36,

    OSIRIS-REx所射中的那顆具體的B型小行星叫做1999 RQ36。

  • though now it's known by the much handier nameBennuafter an ancient Egyptian bird deity.

    雖然現在它被一個更方便的名字 "Bennu "所熟知,因為它是一個古埃及的鳥神。

  • Clearly with the spacecraft namedOSIRISwe're going for an Egyptian theme here.

    很明顯,這艘太空梭被命名為 "OSIRIS",我們要在這裡打造一個埃及主題。

  • The asteroid looks sort of like a lumpy misshapen ball of clay,

    這顆小行星看起來有點像一個塊狀的畸形泥球。

  • and is about 500 meters in diameter, a bit bigger than the Empire State building.

    且直徑約500米,比帝國大廈還要大一些。

  • Since December of 2018, OSIRIS-REx has been surveying and orbiting Bennu,

    自2018年12月以來,OSIRIS-REx一直在對Bennu進行勘測和繞行。

  • mapping its surface, tracking its spin, and gaining experience flying close to a small body.

    繪製它的表面,跟蹤它的自旋,並獲得接近小體飛行的經驗。

  • Since entering into orbit, OSIRIS-REx has been whizzing around Bennu doing all kinds of science.

    自進入軌道以來,OSIRIS-REx一直在本努周圍飛馳,從事各種科學工作。

  • For example, in 2019 it observed plumes of particles coming up from the asteroid's surface, a surprise discovery.

    例如,2019年,它觀察到小行星表面冒出的粒子羽流,這是一個驚喜的發現。

  • It also found that Bennu is densely covered in boulders, when astronomers expected it to be much smoother.

    它還發現,本努密佈著巨石,而天文學家預計它將更加光滑。

  • This discovery in particular complicated OSIRIS-REx's main mission:

    這一發現尤其使OSIRIS-REx的主要任務複雜化。

  • touching down on Bennu and collecting a sample of its surface.

    在本努上著陸,並採集了其表面的樣本。

  • Still, through its surveys OSIRIS-REx identified four possible sample sites

    不過,通過調查,OSIRIS-REX還是確定了四個可能的採樣點。

  • where the spacecraft could safely pick up loose regolith,

    在那裡,航天器可以安全地拾取鬆散的碎石。

  • eventually settling on the sight called Nightingale as the best option.

    最終確定了名為 "夜鶯 "的景區為最佳選擇。

  • Keep in mind though, “best optionis a relative term,

    但請記住,"最佳選擇 "是一個相對的術語。

  • and Nightingale is only about the width of three parking spaces and surrounded by enormous boulders.

    而南丁格爾只有三個車位的寬度,而且周圍都是巨大的石塊。

  • NASA couldn't just send the spacecraft barging in there,

    美國宇航局不能就這樣把航天器闖進去。

  • so the mission planned for two rehearsals before the actual landing to make sure everything would go smoothly.

    所以任務計劃在實際著陸前進行兩次彩排,以確保一切順利。

  • The first rehearsal in April 2020 went off without a hitch,

    2020年4月的第一次彩排順利進行。

  • with the spacecraft going through the first two of four steps in the sampling sequence.

    與航天器經歷採樣序列中四個步驟中的前兩個步驟。

  • And then the coronavirus threw a wrench in the works and the second rehearsal had to be pushed back to August.

    然後冠狀病毒給工作帶來了麻煩 第二次排練不得不延後到8月。

  • Nonetheless, rehearsal two went through the first three steps of the sampling sequence,

    儘管如此,排練二還是經歷了採樣順序的前三步。

  • up toMatchpointburn where OSIRIS-REx matches the rotation of the asteroid.

    到 "匹配點 "燃燒,OSIRIS-REx與小行星的旋轉相匹配。

  • The spacecraft came within 40 meters of Bennu, even deploying it's sampling arm,

    航天器來到本努40米以內,甚至部署了它的採樣臂。

  • but backed away before making contact.

    但在接觸之前就退縮了。

  • Keep in mind that Bennu is so far from Earth that it takes radio signals about 16 minutes to reach the spacecraft.

    要知道,貝努距離地球太遠,無線電信號需要大約16分鐘才能到達航天器。

  • Performing the sampling manually is not an option, OSIRIS-REx must do it autonomously,

    手動執行取樣是不可能的,OSIRIS-REx必須自主執行。

  • so the last rehearsal gave the onboard navigation systems as much detailed info as possible

    所以最後一次演練給了機載導航系統儘可能多的詳細信息。

  • and confirmed that yes, OSIRIS-REx could set its arm on Bennu's surface safely.

    並確認,是的,OSIRIS-REX可以將其臂膀安全地放在貝努的表面。

  • With two rehearsals in the bag, the next step is to go all the way and try and grab a piece of Bennu.

    有了兩次彩排的經驗,下一步就是要全力以赴,爭取搶到一塊本命年。

  • The first attempt is scheduled for October 20th 2020.

    第一次嘗試定於2020年10月20日。

  • If the collection head makes contact with Bennu,

    如果採集頭與本努接觸。

  • the collection arm will spray pressurized nitrogen gas to kick up dust and rocks for the spacecraft to grab before backing away.

    收集臂會噴出加壓氮氣,踢起塵土和石塊,讓航天器在後退前抓住。

  • The collection itself should only last about 5 seconds, a real quick touch-and-go, or TAG for short.

    收集本身的時間應該只有5秒左右,真正的一觸即發,簡稱TAG。

  • Once away from Bennu, OSIRIS-REx will leave its arm extended and spin.

    一旦離開Bennu,OSIRIS-REx就會讓它的手臂伸展並旋轉。

  • Before collecting anything, OSIRIS-REx performed a spin with an empty sampling arm.

    在收集任何東西之前,OSIRIS-REx用一個空的採樣臂進行了旋轉。

  • Comparing the difference in inertia of the empty and full spins

    比較空轉和滿轉的慣性差異。

  • is NASA's way of measuring how much regolith was gathered, since you can't weigh the sample in space.

    是美國宇航局測量收集了多少碎石的方法,因為你不能在太空中稱量樣品。

  • If the sample is under the targeted 60 grams of regolith,

    如果樣品在目標60克的攝取量之下。

  • OSIRIS-REx will try again.

    OSIRIS-REx將再次嘗試。

  • It has three containers of nitrogen aboard, meaning it has three tries to get it right.

    它的船上有三個容器的氮氣,也就是說它要試三次才行。

  • Assuming all goes well, OSIRIS-REx will send the sample back to Earth, arriving in September 2023.

    假設一切順利,OSIRIS-REx將把樣本送回地球,於2023年9月抵達。

  • Then we'll get a chance to look at something extraordinary:

    那我們就有機會看看一些不尋常的東西。

  • a pristine piece of our early solar system.

    早期太陽系的一塊純淨碎片

  • Will the organic compounds held in the samples give us some clue as to where we came from,

    樣本中的有機化合物能否給我們提供一些線索,讓我們知道我們從哪裡來。

  • or will the debate continue among philosophers and scientists?

    還是會在哲學家和科學家之間繼續爭論?

  • We're just going to have to wait to find out.

    我們只能等著瞧了。

  • Another reason to visit Bennu is it has a relatively high chance to collide with Earth late in the 22nd century,

    去本努的另一個原因是它有比較大的機會在22世紀末與地球相撞。

  • so studying it up close can help us prepare to defend against it.

    所以近距離研究它可以幫助我們做好防禦準備。

  • Hopefully it doesn't come to that and OSIRIS-REx is the closest humanity ever comes to this massive space rock.

    但願不會出現這種情況,OSIRIS-REX是人類有史以來最接近這塊巨大太空岩石的地方。

  • If you want to learn about another spacecraft setting foot on foreign worlds,

    如果你想了解另一個踏上異國世界的航天器。

  • check out this countdown to launch episode on Japan's aerospace agency's MMX,

    請看日本航天局的MMX的發射倒計時節目。

  • which has its sights set on the moons of Mars.

    它的目標是火星的衛星。

  • Thanks for watching, be sure to subscribe, and I'll see you next time on Seeker.

    感謝您的觀看,一定要訂閱,我們下期《求是》再見。

On the list of all-time big picture questions, “Where did we come from?' has got to be near the top.

在所有的大圖片問題的列表中,"我們從哪裡來?"一定是接近頂部。

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