But in an irony of history, we may stop ourselves from going into space the more we do it.

但諷刺的是，我們可能會因為上太空的次數增加而越無法再上太空。

With every rocket launched and with every satellite deployed, we're creating a trap for ourselves that gets deadlier and more dangerous every year.

隨著每枚發射的火箭和每顆部署的衛星，我們正在為自己創造一個每年都會變得越來越致命和危險的陷阱。

If it's ever activated, it could end the Space Age and trap us on our planet for decades, or even centuries.

一旦啟動這個陷阱，就可能會結束太空時代，並將我們困在我們的星球上數十年，甚至數百年。

Getting something into space is incredibly hard.

把東西送上太空是非常困難的。

To do so, you need to move very, very fast.

要上太空，你必須移動地非常非常快。

At first, straight up, to leave the atmosphere.

首先，直線上升以離開大氣層。

Then, sideways, to begin a sort of circling around the earth.

然後，轉成橫的，開始繞地球轉。

Still, very, very fast.

你仍保持高速。

If you do that successfully, you can enter a low Earth orbit.

如果你成功完成以上步驟，你就可以進入低地球軌道。

And once in orbit, it's very hard to get out of orbit.

一旦進入軌道，就很難離開軌道了。

Unless you have energy to spare, you're sort of locked in here, falling around the earth forever.

除非你有很多能量，不然你就會被困在這裡，永遠繞著地球摔落。

That's great for things we want to stay up, like space stations and satellites.

這對我們想要放在天上的東西而言很有用，比如太空站和衛星。

And so we moved the majority of humanity's space infrastructure to this place.

因此，我們將大部分人類的太空基礎設施移到這個地方。

Just a few hundred kilometers above the surface.

距離地面只有幾百公里。

Just high enough so that the atmosphere is so thin, that orbiting things can stay up for centuries before air resistance can slow them enough to bring them back to Earth.

剛好高到大氣夠稀薄，讓軌道上的東西可以待上幾個世紀，而不會因為空氣阻力使它們減速到足以掉回地球。

But this is also the source of our deadly trap.

但這也是我們致命陷阱的來源。

Rockets are really metal cylinders that keep big parts of fuel in place.

火箭其實是裝著一堆燃料的金屬圓筒。

Whenever a portion of the fuel has been spent, the empty tanks are dropped to make the rocket lighter.

每當一部分燃料耗盡時，就會丟掉空的油箱，使火箭更輕。

Some parts crash down to earth or burn up in the atmosphere.

有些零件摔回地面或在大氣層中燒盡。

But most of the useless rocket parts stay up and begin to orbit the planet.

但是大多數無用的火箭零件都留在天上並開始繞著行星運行。

After decades of space travel, low Earth orbit is a junkyard of spent boosters, broken satellites and millions of pieces of shrapnel from missile tests and explosions.

經過幾十年的太空旅行，低地球軌道成了垃圾場，有著廢棄的助推器、壞掉的衛星和導彈測試及爆炸造成的數百萬片碎片。

Right now, we know of around 2,600 defunct satellites, 10,000 objects bigger than a monitor, 20,000 is large as an apple, 500,000 pieces the size of a marble and at least 100 million parts so small they can't be tracked.

現在，我們知道大約有 2,600 顆的報廢衛星，10,000 個比螢幕大的物體，20,000 個跟蘋果一樣大，500,000 個彈珠大小的物體和至少 1 億件小到無法追蹤的東西。

This debris is moving at speeds of up to 30,000 km/h circling earth on criss-crossing orbits multiple times a day.

這些碎片以最高時速每小時 30,000 公里的速度移動，以十字形交錯的軌道一天環繞地球數次。

Orbital speeds are so fast that being hit by debris the size of a pea is like being shot by a plasma gun; on impact, the debris vaporizes releasing enough energy to punch holes straight through solid metal.

軌道速度如此之快，以至於被豌豆大小的碎片擊中就像被電漿槍打中一樣；當撞擊發生時，碎片會蒸發，釋放的能量足以打穿硬實的金屬。

So, we've covered the space around our planet with millions of deadly pieces of destruction, and we also put a trillion dollar global infrastructure network right in the danger zone.

因此，我們用數百萬件致命的破壞物包圍了我們的星球，我們還把價值一兆美元的全球基礎設施網絡架設在這個危險地帶中。

It performs critical duties essential to the modern world: global communication, GPS and navigation, collecting weather data, looking out for asteroids and all manner of scientific discoveries things we would miss very much if they suddenly went away.

這些設施負責對現代世界至關緊要的工作：全球通訊、GPS 和導航、收集氣象數據、尋找小行星和各種如果突然失去這些設施，會讓我們錯過的科學發現。

If just one piece sized bullet hits one of our 1,100 working satellites, it will be destroyed instantly.

假使就只有一顆小子彈擊中我們 1,100 顆工作衛星中的其中一顆，它會立即被摧毀。

Three or four satellites are already being destroyed this way every year.

每年都有三到四顆的衛星已因為這樣而摧毀。

As the number of satellites and the amount of junk in orbit is expected to grow tenfold in the next decade, we're approaching a tipping point.

隨著未來十年衛星數量和軌道垃圾量預計將增長十倍，我們正在接近一個臨界點。

But the worst thing in space is not tiny pieces of junk.

但太空中最糟糕的事不是小型垃圾。

The worst thing would be an unstoppable chain reaction that turns a lot of non junk things into junk; for example: if two satellites hit each other in just the right way.

最糟糕的情境是不可阻擋的連鎖反應，把很多非垃圾變成垃圾；例如：如果兩顆衛星以相對的方向相互撞擊。

If satellites collide, they don't stop and fall out of the sky. It's more of a splash than a crash.

如果衛星互撞，它們並不會停止並從天而降。情況比較像水花四濺，而非車禍。

Orbital speeds are so fast solid pieces spray right through each other, transforming the two satellites into clouds of thousands of little things still fast enough to destroy more satellites

軌道速度如此之快，固體碎片四散噴射於彼此之中，將這兩顆衛星變成數以千計且仍然夠快，可以摧毀更多衛星的小東西。

This could trigger the slowest and most destructive sort of domino effect, a collision cascade.

這可能會觸發最慢和最具破壞性的骨牌效應，撞擊連鎖反應。

Like a shotgun spray, each collision creates more bullets.

像霰彈槍一樣，每次碰撞都會產生更多的子彈。

What was once a single tiny target very unlikely to hit anything.

一開始的一顆小子彈不太可能打中東西。

Becomes a wall of destruction, hungry to make more.

但現在成了不停發生的破壞源。

As more and more satellites are destroyed, the destruction accelerates exponentially.

隨著越來越多的衛星被摧毀，破壞的情形加速倍增。

Eventually destroying everything parked in orbit.

最終摧毀在軌道上的一切。

But space is very empty. So the first few collisions may take a long time.

但太空非常空。因此，前幾次的碰撞可能需要很長的時間才會發生。

By the time we realize what's happening, it's too late.

而當我們意識到正在發生的事情時，早已為時已晚。

One year one satellite is destroyed and that's no big deal.

一年一顆衛星被摧毀，這沒什麼大不了的。

The next year, five.

第二年，五顆。

The year after 50.

第三年，50顆。

Until there's nothing left.

直到最後什麼也不剩。

The situation in orbit is rapidly worsening and we may already be past the point of no return.

軌道上的情況正在迅速惡化，我們可能已經無法回頭。

Within 10 years, space around Earth may no longer be viable for long term satellites or rockets.

在10年內，地球周圍的太空可能不再適合置放長期衛星或火箭。

The worst case scenario is horrifying.

最糟糕的情景很可怕。

A debris field made of hundreds of millions of pieces, many too small to track moving at 30,000 km/h.

由數億個碎片組成的碎片場，充滿小到無法追蹤，以時速 30,000 公里移動的碎片。

It would effectively create a deadly barrier around earth.

它將著實在地球周圍創造一堵致命的屏障。

Possibly too dangerous to cross.

可能危險到無法穿越。

Dreams of moon bases, Mars colonies or space travel at all may be set back centuries.

月球基地、火星殖民地或太空旅行的夢想可能要延後好幾個世紀。

And the loss of our space infrastructure would send some of the technology we rely on daily back to the 1970s.

而一旦我們失去了太空基礎設施，那將使我們每天依賴的一些科技倒退回 1970 年代。

But it might not be too late to clean up our mess.

但是清理我們的爛攤子可能還不會太晚。

While the space industry has become better at avoiding space junk, its still growing fast and occasional weapon tests don't help.

雖然航太工業愈來愈懂得減少太空垃圾，它仍快速增加及偶爾發生的武器測試於事無補。

So there have been a couple of wild but also serious suggestions about how to quickly remove as much deadly space junk as possible without creating more in the process.

所以有一些瘋狂但認真的建議，關於如何盡可能快速移除越多的致命太空垃圾，而不在過程中製造更多。

Lots of ideas are being thrown around.

很多想法都被提出。

And some of the most seriously considered involve capture and return missions, which are being tested now.

一些最被嚴肅看待的手法涉及了現在正在測試中的捕獲和返回任務。

One method involves meeting a piece of junk in orbit with a small satellite and loaded with a net.

一種方法是用一顆小衛星在軌道上和一塊垃圾會合，然後用網子抓住。

Once caught, a small rocket could be used to bring it down towards Earth.

一旦被抓住，可以使用一個小火箭將其帶回地球。

Targets too large for a net might be instead caught with a harpoon on a tether.

對於網子而言太大的目標，可以用綁了纜繩的魚叉捕捉。

Instead of firing a rocket, the cleaner would deploy a large sail to produce atmospheric drag and accelerate orbital decay.

不使用火箭，而是清潔器部署一個大帆以產生大氣拉力，並加速軌道上物體的墜落。

And there are lots of other wild sci-fi sounding proposals too.

此外也還有許多其他聽起來狂野的科幻提案。

Some might use giant electromagnets.

有些可能會使用巨型電磁鐵。

These magnetic tugs work by pushing on the magnetic components inside satellites that they use to stabilize, and orientate themselves in Earth's magnetic field.

這些磁性拖船會推動衛星內部用於穩定的磁性元件，並將它們導回地球的磁場中。

These may be safer and more reliable than nets and harpoons, because they never have to make contact with the junk they're handling.

這些可能比網子和魚叉更安全'、更可靠，因為它們永遠不必接觸它們正在處理的垃圾。

So there's no risk of accidentally breaking up their target into more junk.

因此，不會有意外將目標分解為更多垃圾的風險。

As for the tiniest bits of junk, lasers might be the key to vaporizing them entirely.

至於最微小的垃圾，雷射槍可能是完全蒸發它們的關鍵。

Satellites with lasers wouldn't need to visit their targets. They can shoot them from far away.

帶雷射的衛星不需要靠近目標。他們可以從遠處射擊。

Large objects can't exactly be shot down.

大型物體很難被擊落。

But lasers can be used to ablate them, or burn tiny amounts of material off the site to push the junk to a safer orbit.

但是雷射可以用來消融它們，或者燒掉該基地少量的材料，並將垃圾推到更安全的軌道。

Whatever technology we used at the end, we better start doing something soon before 100 million bullets become a trillion and the trap is set.

無論我們最終使用什麼技術，我們最好盡快開始，免得一億個子彈成為一兆，那時陷阱就無法解除了。

If we don't act, our adventure in space might end before it's even begun.

如果我們不採取行動，我們在太空中的冒險可能會在才正要開始之前就結束。

If our days of dreaming about space exploration might be numbered anyway, we better put them to good use.

即使我們夢想太空探索的日子接近尾聲，我們最好好好利用。

One of the things we most like to spend our time on is learning more about our universe.

我們最可能會去做的其中一件事就是去更了解我們的宇宙。

And to do that you can just keep watching.

要做到這一點，你可以繼續觀看。

Kurzgesagt and Brilliant are collaborating on a six-part video series about our favorite science and space topics.

Kurzgesagt 和 Brilliant 正在合作製作一個關於我們最喜歡的科學和太空主題的六部系列影片。

Kurzgesagt has worked with Brilliant for a bit.

Kurzgesagt 已經和 Brilliant 合作一段時間了。

And we love how they teach you science and maths in a practical way.

我們喜歡他們教你科學和數學的特定方式。

By guiding you through problems step by step, so you can actually understand the concepts behind them.

透過逐步指導您解決問題，你就可以真正理解它們背後的概念。

And maybe one day use your knowledge on problems like space junk, or at least your science projects to start with.

也許有一天你會把知識運用在處理太空垃圾上，或者至少你自己的科學專案。

If you'd like even more edutainment, go to Brilliant.org/nutshell and sign up for free.

如果你想要更多的寓教於樂，請至 Brilliant.org/nutshell 並免費註冊。

The first 688 people to use the link get their annual premium membership at a 20% discount!

首批使用該連結的 688 人會獲得 20％ 折扣的年度高級會員資格！

And also support our collaboration with Brilliant!

並支持我們與 Brilliant 的合作！