Name: 美國宇航局的這個航天器可以揭開生命起源的面紗 (This NASA Spacecraft Could Unveil the Origins of Life)
Uploaded: 2020-10-14T19:15:57.000Z
Duration: 5 min 17 s

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

with the goal of collecting samples from an asteroid.

But not just any asteroid — specifically, 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 name “Bennu” after 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 named “OSIRIS” we'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 option” is 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 to “Matchpoint” burn 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。

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,

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

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。

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.

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.

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.

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。