At first glance, the visitor, named 2I/Borisov, seemed to be rather ordinary,

乍一看，這位名為2I/Borisov的訪客似乎相當普通。

but studies since have revealed signs that it is far from an average comet.

但此後的研究發現，有跡象表明它遠遠不是一顆普通的彗星。

Now, two research studies released in March 2021 have shed new light on our visitor, and helped unveil information

現在，2021年3月發佈的兩項研究為我們的訪客帶來了新的啟示，並幫助揭開了資訊

about our own solar system. When Borisov was first sighted by an amateur astronomer, initial data suggested it was a typical comet.

關於我們自己的太陽系。當鮑裡索夫第一次被一位業餘天文學家看到時，最初的數據表明它是一顆典型的彗星。

Meaning it was made of things like ice, dust, and gassy materials that researchers had all seen before in our solar system.

這意味著它是由諸如冰、塵埃和氣體材料組成的，研究人員以前都在我們的太陽系中見過。

Soon after its finding, NASA's Scout system at JPL automatically identified the comet as a potential interstellar object.

在它被發現後不久，美國宇航局在JPL的偵察系統自動將這顆彗星識別為潛在的星際物體。

This software alerted astronomers across the world, and they quickly pointed their instruments toward Borisov to learn more.

這個軟件提醒了全世界的天文學家，他們迅速將他們的儀器指向鮑裡索夫以瞭解更多。

And what exactly were those astronomers looking for in this alien comet?

而那些天文學家究竟在這顆外星彗星中尋找什麼呢？

In order to study a comet, astronomers take a look at the particles being expelled from the comet's surface.

為了研究一顆彗星，天文學家看了一下從彗星表面排出的粒子。

In fact, you're probably most familiar with images showing a comet shedding their outermost layer, in what's known as a coma.

事實上，你可能最熟悉的是顯示彗星最外層脫落的影像，即所謂的彗星。

The coma forms when comets pass close to their host star and are bombarded by heat and radiation.

當彗星接近其主星並受到熱量和輻射的轟擊時，彗星就會形成。

Dust and debris break off from the comet's main body, and ice sublimates into gas.

塵埃和碎片從彗星的主體中脫離出來，冰昇華為氣體。

And by studying the released particles, observers are able to make educated guesses about the composition

通過研究被釋放的粒子，觀察者能夠對其組成作出有根據的猜測。

and the history of the comet. Previous studies found that Borisov likely contains between nine and twenty-six times

以及該彗星的歷史。以前的研究發現，鮑裡索夫可能含有九到二十六倍的

more carbon monoxide than other comets we've seen before, meaning that Borisov probably formed

比我們以前見過的其他彗星有更多的一氧化碳，這意味著鮑裡索夫可能形成了

in extremely cold temperatures around negative 250 degrees Celsius. And these latest studies have built upon

在負250攝氏度左右的極冷溫度下。而這些最新的研究是建立在

this conclusion to provide additional evidence of the comet's alien nature.

這一結論為該彗星的外星性質提供了額外的證據。

Using different methodologies, two recent studies took a closer look at Borisov's coma.

使用不同的方法，最近的兩項研究對鮑裡索夫的昏迷進行了仔細的研究。

The first from the Armagh Observatory and Planetarium measured the reflected light of the coma.

第一個來自Armagh天文臺和天文館，測量了彗星的反射光。

As the light from the sun scatters through the particles, astronomers are able to determine

當來自太陽的光通過粒子散射時，天文學家能夠確定

size, composition, and shape based on the electromagnetic waves.

基於電磁波的大小、組成和形狀。

The team concluded that the observed light was being reflected through extremely small particles,

研究小組得出結論，觀察到的光線是通過極小的顆粒反射的。

suggesting that the comet is close to its original form.

這表明這顆彗星接近於它的原始形態。

This ultimately helps us to better understand the comet's origin.

這最終有助於我們更好地瞭解該彗星的起源。

And almost simultaneously, astronomers at the European Southern Observatory conducted a separate study

而幾乎同時，歐洲南方天文臺的天文學家們進行了一項單獨的研究

that measured heat signatures from Borisov's coma.

測量鮑裡索夫昏迷時的熱信號。

With a combination of data from VLT and the Atacama Large Millimeter/submillimeter Array, or ALMA, for short,

通過VLT和阿塔卡馬大型毫米/亞毫米陣列（簡稱ALMA）的數據組合。

the team discovered millimeter-sized grains rich in carbon monoxide and water being expelled from the comet.

研究小組發現了從彗星上排出的富含一氧化碳和水的毫米級顆粒。

These findings suggest two things: number one, that Borisov comes from an extremely cold environment,

這些發現表明了兩件事：第一，鮑裡索夫來自一個極其寒冷的環境。

and number two, that it was more of a traveler than a stationary rock,

第二，它更像是一個旅行者，而不是一個固定的岩石。

beginning in the inner area of a star system before being pushed outward and collecting ice along its journey.

從一個恆星系統的內部區域開始，然後被向外推送，沿途收集冰。

Borisov likely moved further and further away until finally resting in an area deep within its star system

鮑裡索夫很可能越走越遠，直到最後在其恆星系統深處的一個區域休息。

and undisturbed by either heat or radiation. Astronomers believe the process of Borisov exchanging materials

並且不受熱量或輻射的干擾。天文學家認為鮑裡索夫交換材料的過程

was influenced by giant planets in the early universe through a process called “gravitational stirring”.

在早期宇宙中，通過一個稱為 "引力攪拌 "的過程，受到巨型行星的影響。

And this same process is thought to have contributed to the formation of our solar system.

而這一過程也被認為有助於我們太陽系的形成。

Unfortunately for researchers, Borisov has made its exit out of our Solar System, and they won't be able to make

對研究人員來說，不幸的是，鮑裡索夫已經離開了我們的太陽系，而他們將無法使

any new observations of the comet.

對該彗星的任何新觀察。

These studies have left the astronomy community with many questions:

這些研究給天文學界留下了許多疑問。

Is the star system Borisov hails from really so different from our own?

鮑裡索夫所來自的星系與我們的星系真的如此不同嗎？

And how much has the comet actually changed since its creation?

而這顆彗星自誕生以來究竟發生了多大的變化？

And we'll hopefully get closer to answering some of these questions as teams across the world

隨著世界各地的團隊，我們將有望更接近於回答其中的一些問題

are looking to study comets more closely, and learn about the star systems they originally come from.

他們希望更仔細地研究彗星，並瞭解它們最初來自的恆星系統。

The Vera C. Rubin Observatory is set to open in late 2022 and will hopefully detect interstellar objects while surveying the sky.

維拉-C-魯賓天文臺將於2022年底開放，並有望在勘測天空時探測到星際物體。

And the European Space Agency aims to launch its Comet Interceptor mission in 2029

而歐洲航天局的目標是在2029年發射其彗星攔截器任務

to pursue traveling objects as they move through our Solar System, hoping to give us an even closer look

追蹤穿越太陽系的天體，希望能讓我們更近距離地看到它們。

at visitors from distant galaxies.

在來自遙遠的星系的訪客。

Including Borisov, did you know that humans have only seen two objects from outside our solar system?

包括鮑裡索夫，你知道人類只見過兩個來自太陽系外的物體嗎？

The first discovered in 2017, Oumuamua, which is the flat rock thought by many to be an alien spacecraft.

2017年發現的第一個，Oumuamua，這是許多人認為是外星飛船的扁平岩石。

To learn more about the first interstellar comet, check out this episode on Oumuamua here.

要了解有關第一顆星際彗星的更多資訊，請在這裡查看有關Oumuamua的這一集。

Make sure to subscribe and thanks for watching.

請務必訂閱，並感謝您的觀看。