Right now, there are about 7,000 in orbit, and the pace of launches is only set to accelerate as space travel gets cheaper and companies envision mega-constellations.

現在，大約有 7000 個在運行中，而且隨著太空旅行變得更便宜，某些公司計劃投放通訊衛星巨型星系，發射衛星的速度只會加快。

While space may be a pretty big place, there is a finite limit to just how much stuff can safely be whizzing around the Earth.

雖然太空可能是一個相當大的地方，但有一個有限的限制，即有多少東西可以安全地在地球周圍呼嘯而過。

So, to paraphrase a song from my youth, what are we gonna do with all that junk, all that junk in outer space?

所以，套用我年輕時的一首歌，我們要怎麼處理那些垃圾，外太空的那些垃圾？

And believe me, there is already a lot of junk up there.

相信我，上面已經有很多垃圾了。

Of those 7,000 or so satellites I mentioned, about 3,000 of them are defunct and not serving any purpose.

在我提到的那 7000 多顆衛星中，大約有 3000 顆已經停用，沒有任何作用。

Some of them are huge, like ESA's Envisat which is as big as a double-decker bus.

其中一些是巨型的，如歐洲太空總署的 Envisat ，有雙層巴士那麼大。

There have been several close calls as dead satellites guided only by the hand of physics nearly collided.

有幾次險象環生，任由物理引導的廢棄衛星差點發生碰撞。

Sometimes they only miss each other by just a dozen meters, and sometimes they don't miss at all.

有時它們只與對方相差十幾米，有時它們根本直接撞上。

Like in 2009 when an inactive Russian Cosmos satellite collided with a very-much active Iridium communications satellite.

比如在 2009 年，一顆不活躍的俄羅斯宇宙號衛星與一顆非常活躍的銥衛星相撞。

That collision generated thousands of pieces of debris, and in space, the small stuff can't be overlooked.

這次碰撞產生了數以千計的碎片，而在太空中，小東西是不能被忽視的。

NASA estimates there are more than 23,000 pieces of debris larger than 10 centimeters in orbit around the Earth, and there are hundreds of millions more pieces smaller than that.

美國國家航空航天局估計有超過 23,000 塊大於 10 公分的碎片散布在圍繞地球的軌道上，而且還有數以億計的比這更小的碎片。

Doesn't sound very big, but at the extreme speeds they're moving, they pose a risk to active satellites and the International Space Station.

聽起來不是很大，但在它們極端的移動速度下，它們對活動衛星和國際太空站構成了風險。

In fact, in May of 2021, astronauts inspecting the ISS discovered damage to the station's robotic arm that was caused by one of these tiny pieces of junk.

事實上，在 2021 年 5 月，檢查國際太空站的太空人發現太空站的機械手臂受到了損壞，這是由其中一個微小垃圾造成的。

The arm is still functioning, but it could have been worse.

機械手臂仍在運作，但情況可能更糟。

The worst-case scenario was imagined by NASA scientist Donald J. Kessler back in 1978.

最壞的情況是美國宇航局科學家唐納德・J・凱斯勒在 1978 年就想像到的。

The so-named Kessler syndrome is where more satellites like Cosmos and Iridium collide and the resulting debris creates a runaway chain reaction that damages more satellites, creating more debris that ultimately renders low-earth orbit unusable.

所謂的凱斯勒綜合症是指更多像宇宙號和銥星這樣的衛星碰撞而產生的碎片會產生失控的連鎖反應，損害更多的衛星，產生更多的碎片，最終使低空地球軌道無法使用。

There are a few solutions in the works in an effort to stave off that bleak possible future.

有一些解決方案正在進行中，以努力避免這種可能的黯淡未來。

A proof-of-concept for one of them launched in March of 2021.

其中一個的概念驗證於 2021 年 3 月推出。

The project, dubbed the End of Life Services by Astroscale demonstration, or ELSA-d, is a collaboration between the Tokyo startup Astroscale and JAXA.

該項目被稱為「天體規模的生命終結服務」，即 ELSA-d，是東京創業公司 Astroscale 和 JAXA 之間的合作。

The demonstrator consists of two satellites, a larger one with a magnet and a smaller one with a plate the magnet is designed to latch onto.

該展示機由兩顆衛星組成，一顆較大的衛星上有一個磁鐵，還有一個較小的，上面有一塊盤子，讓磁鐵可以吸附在上面。

The two launched attached to one another but once all systems check out, the satellites will conduct a test in three stages.

這兩顆發射的衛星彼此相連，但一旦所有系統檢查完畢，這兩顆衛星將分三個階段進行測試。

First, they'll split up and the larger one will attempt to recapture its counterpart.

首先，它們會分開，較大的那個會試圖重新聯結它的對應物。

If all goes well, they'll split again, this time with the target satellite traveling in a tumbling orbit that more closely mimics the behavior of space junk.

如果一切順利，它們將再次分離，這次目標衛星將在翻滾的軌道上行駛，更加接近模仿太空垃圾的行為。

If they recouple a second time, they'll split once more and the larger one will lose the smaller one, intentionally.

如果它們第二次重新結合，它們會再一次分裂，大的那個會刻意地拋棄小的那個。

Now, If they manage to find each other and couple a third time, the demonstrator will be considered a success and ELSA-d will deorbit and burn up in the atmosphere.

現在，如果他們設法找到對方並第三次結合，該展示機將被認為是成功案例，而 ELSA-d 將脫離軌道並在大氣中燒毀。

Even if all goes as planned, this system has its limits.

即使一切按計劃進行，這個系統也有其侷限性。

Astroscale's approach to junk management requires the space junk to have that magnetic plate, so while it could work for future satellites that incorporate it into their design, it doesn't solve the problem of the several thousand dead hunks of metal that are currently up there.

Astroscale 的垃圾管理方法要求太空垃圾有那個磁板，所以，雖然未來的衛星可能將其納入設計中，Astroscale 的垃圾管理方法便能夠適用， 這並不能解決目前在上面幾千塊失去作用的金屬塊的問題。

To tackle that issue, the Swiss company ClearSpace is developing a tentacled contraption and aims to take down a large piece of an ESA booster rocket by 2025.

為了解決這個問題，瑞士公司 ClearSpace 正在開發一種有觸手的裝置並力爭在 2025 年前拿下歐空局的一大塊火箭推進器。

One other idea is to refuel dead or dying satellites in orbit, eliminating the need to replace them or at least making it possible for them to move out of harm's way.

另一個想法是為在軌道上死亡或垂死的衛星加油，消除替換他們的需要，或至少使他們有可能遠離危險。

NASA is planning one such refueling mission called OSAM-1 in the coming years.

美國宇航局正計劃在未來幾年內進行一次這樣的加油任務，名為 OSAM-1。

Of course, there is another option and that is just…to not send up so many new satellites.

當然，還有另一個選擇，那就是......不要發送這麼多新衛星。

If space junk is allowed to come down at a faster rate than we put stuff up there, the skies will steadily become less crowded.

如果讓太空垃圾以比我們把東西放上去更快的速度下來，天空將穩定地變得不那麼擁擠。

But with multiple companies planning global communication networks each made up of thousands of satellites, that idea probably isn't getting off the ground.

但隨著多家公司規劃全球通信網路，每個網路都由成千上萬的衛星組成，這個想法可能不會成功進行。

This issue is a long way from being solved.

這個問題距離解決，還有很長的路要走。

There are so many satellites in orbit now that even if we stopped all launches, some scientists believe the Kessler syndrome could still become a reality.

現在有這麼多的衛星在軌道上，即使我們停止所有發射，一些科學家認為凱斯勒綜合症仍可能成為現實。

Space junk comes in such a wide variety of shapes and sizes that no one approach will be the solution that cleans up low Earth orbit.

太空垃圾的形狀和大小如此之多，沒有單一一種方法會成為清理低空地球軌道的解決方案。

And these technologies could also have a sinister side: something that de-orbits a junk satellite could also bring down an active one, something that will no doubt concern governments and militaries of the world.

而這些技術也可能有陰險的一面。使廢舊衛星脫離軌道的東西也可能使還在運行的衛星墜落，這無疑會引起世界各國政府和軍隊的關注。

Doing something with all that junk is going to require a lot of creativity, trust, and forward-thinking if we're going to make sure there's enough space in space.

如果我們要確保在太空中有足夠的空間，處理這些垃圾將需要大量的創造力、信任和前瞻性思維。

If you're curious why companies would want to create mega-constellations of satellites, check out my video on SpaceX's Starlink project here.

如果你好奇為什麼公司會想要創建通訊衛星巨型星系，請看我關於 SpaceX 的 Starlink 項目的視頻。

Are you worried about the Kessler Syndrome going from scary hypothetical to reality?

你是否擔心凱斯勒綜合症會從可怕的假想變成現實？

Why or why not?

為什麼會或為什麼不會呢？

Sound off in the comments, be sure to subscribe, and I'll see you next time on Seeker.

在評論中發表意見，請務必訂閱，我們下次在 Seeker 上見。