Name: 天降橫禍是真的！地球上有人被太空碎片擊中的機率高達 3%！ (The 3% Chance Someone on Earth Will Be Hit By Space Debris | WSJ)
Uploaded: 2025-06-03T21:01:20.000Z
Duration: 8 min 56 s

Space debris is falling to Earth in record numbers.

太空碎片正以創紀錄的數量墜落地球。

While most objects burn up on re-entry, a small percentage survives to strike the ground.

雖然大多數物體在重返大氣層時會燃燒殆盡，但也有一小部分會倖存下來，撞擊地面。

There's a feeling we are not safe, and it's true.

我們有一種不安全的感覺，這是真的。

Recent examples of space debris hitting the surface of the planet have sparked safety concerns.

最近發生的太空碎片撞擊地球表面的事件引發了人們對安全的擔憂。

As space launch traffic reaches an all-time high.

隨著航天發射流量達到歷史新高。

It's not a question of if, it's a question of when.

這不是「是否」的問題，而是「何時」的問題。

So just how dangerous is space debris to humans on Earth?

那麼，太空碎片對地球上的人類到底有多危險呢？

Early morning on February 19th, people in Germany, the UK, Denmark and Sweden reported seeing bright objects streaking across the sky.

2 月 19 日清晨，德國、英國、丹麥和瑞典的人們報告說看到明亮的物體劃過天空。

An upper stage of a SpaceX Falcon 9 rocket was breaking up as it made an uncontrolled re-entry over Europe.

SpaceX 的獵鷹 9 號火箭在歐洲上空失控重返大氣層時，其末級火箭正在解體。

It had been launched from California and was intended to re-enter Earth's atmosphere in a controlled descent over the ocean.

它從加州發射升空，打算在海洋上空有控制地下降，重新進入地球大氣層。

But a propellant leak caused the rocket's second stage to remain in orbit longer than planned, leading to its uncontrolled re-entry weeks later.

但由於推進劑洩漏，火箭第二級在軌道上停留的時間超過了計劃，導致火箭在幾周後失控重返大氣層。

Poland's space agency said debris scattered across multiple locations in the country's west.

波蘭航天局稱，碎片散落在該國西部的多個地點。

We call it an uncontrolled re-entry for a good reason because you cannot predetermine where it will form.

我們稱其為不受控制的重返是有道理的，因為你無法預先確定它會在哪裡形成。

The European Space Agency believes up to 200 tonnes of space hardware, including defunct satellites and spent rocket stages, re-enters the Earth's atmosphere in an uncontrolled manner every year. 200 tonnes is a lot.

歐洲航空局認為，每年有多達 200 噸的太空硬體，包括失效的衛星和報廢的火箭級，以不受控制的方式重新進入地球大氣層。200 噸可真不少。

It basically means there's almost a daily event of a larger object coming back.

這基本上意味著，幾乎每天都會有一個較大的物體回來。

But it does not mean that nothing will happen because 20 to 40% of that mass can reach the ground on average.

但這並不意味著什麼都不會發生，因為平均有 20% 至 40% 的質量可以到達地面。

Experts say the chances of that debris striking a human are very low.

專家說，這些碎片擊中人類的機率非常低。

About 70% of the Earth's surface is ocean and large parts of land are uninhabited.

地球表面約 70% 是海洋，大片陸地無人居住。

But there is still a risk and it is growing.

但風險依然存在，而且還在增加。

So it's going to go up or it's going to come down.

Darren McKnight is a senior technical fellow at US space tracking firm LEO Labs and Andrew Monom heads space environment sustainability for EUMETSAT, a European Weather Satellite Agency.

Darren McKnight是美國太空跟蹤公司 LEO Labs 的資深技術研究員，Andrew Monom 則是歐洲氣象衛星應用組織（EUMETSAT）太空環境可持續性的負責人。

They co-authored this study on ground hazards caused by space debris re-entry.

他們共同撰寫了這份關於太空碎片重返造成的地面危害的研究報告。

We've looked at both past hazards and, let's say, expected hazards going forward.

我們既研究了過去的危害，也研究了未來的預期危害。

And we are living in an era where we are somewhat blissfully unaware of a number of objects which are raining down on us.

在我們生活的這個時代，我們對許多雨點般落在我們身上的物體一無所知。

An analysis of re-entries over 13 years shows there's nearly a 3% chance that someone, somewhere on Earth, will be injured each year.

對 13 年來再入境情況的分析表明，每年地球上某個地方有人受傷的機率接近 3%。

We have the prospect that something might be falling on our head.

我們有可能被什麼東西砸到頭。

But so far, although several thousand tonnes of space hardware have been re-entered in an uncontrolled way since the beginning of space flight, nobody was harmed.

但迄今為止，雖然自太空飛行開始以來，已經有數千噸的太空硬體在不受控制的情況下重返大氣層，但沒有人受到傷害。

The European Space Agency says for an individual, the chances of being injured by space debris is less than 1 in 100 billion.

歐洲航空局表示，對於個人來說，被太空碎片傷害的機率不到千億分之一。

But despite this, there have been some close calls.

儘管如此，還是有一些險情發生。

In 2024, a piece of debris discarded by the International Space Station three years prior crashed through the roof of a home in Naples.

2024 年，國際太空站三年前丟棄的一塊碎片撞破了那不勒斯一戶人家的屋頂。

NASA said it was part of a 5,800-pound cargo pallet containing batteries that was expected to fully burn up on re-entry.

NASA 說，這是一個裝有電池的5800磅貨物托盤的一部分，預計在重返大氣層時會完全燒燬。

That's a clear case where, you know, there could clearly have been a casualty if someone had been in the vicinity.

這是一個明顯的案例，你知道，如果當時有人在附近，顯然會造成人員傷亡。

Incidents like these have forced space agencies and companies to re-evaluate re-entry models to better predict whether objects will burn up during re-entry.

諸如此類的事件迫使航天機構和公司重新評估重返大氣層模型，以便更好地預測物體在重返大氣層過程中是否會燒燬。

SpaceX made changes to some expendable components of its Dragon spacecraft after some proved more resilient than expected.

SpaceX 對其天龍號太空船的一些消耗性組件進行了改動，因為其中一些組件被證明比預期的更有彈性。

The trunk module, which carries unpressurised cargo, is jettisoned before the spacecraft returns to Earth.

在太空船返回地球之前，裝載未加壓貨物的主幹艙被卸下。

But there have been instances where parts of the trunk have survived and crashed into the ground in Canada, Australia and elsewhere.

但在加拿大、澳洲和其他地方，也有部分艙體倖存下來並墜入地面的情況。

A roughly nine-foot piece was found wedged in the ground here in New South Wales.

在新南威爾士州，人們在地面上發現了一塊大約九英尺長的碎片。

SpaceX subsequently moved its Dragon splashdowns from the coast of Florida to the coast of California, allowing the trunks to be jettisoned in the Pacific.

SpaceX 公司隨後將天龍號的降落地點從佛羅里達州海岸移到了加州海岸，這樣就可以在太平洋上卸下天龍號的尾箱。

The company said it would also implement material changes to some components of Dragon's trunk to improve the probability of it burning up on re-entry.

該公司表示，它還將對天龍號軀幹的一些部件進行實質性改動，以提高它在重返大氣層時燒燬的可能性。

Space debris that is made of low-melting-point materials, like aluminium, will generally burn up or demise at high altitudes during re-entry, while more heat-resistant components made from materials like titanium, stainless steel and beryllium could potentially reach the ground.

由鋁等低熔點材料製成的太空碎片一般會在重返大氣層時在高空燒燬或消亡，而由鈦、不鏽鋼和鈹等材料製成的耐熱性較強的部件則有可能到達地面。

An increasing number of newer satellites are made with materials that are designed to disintegrate upon re-entry.

越來越多的新型衛星採用了可在重返大氣層時解體的材料。

But upper stages in spacecraft which contain tanks, thrusters, this is our problem.

但太空船的末級包含油箱和推進器，這就是我們的問題所在。

Humans have been leaving rocket stages, or rocket bodies, in orbit since the dawn of the Space Age.

自太空時代開始以來，人類就一直在軌道上留下火箭級或火箭體。

In 1957, when the Soviet Union launched Sputnik 1, it also created the first two pieces of human-made orbital debris, the satellite and the rocket that brought it to orbit.

1957 年，蘇聯發射了人造衛星 1 號，同時也創造了人類製造的第一批軌道碎片，即衛星和將其送入軌道的火箭。

The result of over 60 years of subsequent space exploration has been a large number of rocket bodies left in Earth's orbit.

此後 60 多年太空探索的結果是，地球軌道上留下了大量火箭天體。

These are certainly the biggest, most massive objects.

這些無疑是最大、最龐大的天體。

It's the last stage of the rocket that very often ends up orbital, like the satellite that it carries.

它是火箭的最後一級，通常最終會進入軌道，就像它運載的衛星一樣。

This is a digital representation of the more than 20,000 objects in low-Earth orbit by US space-tracking firm LeoLabs.

這是美國太空跟蹤公司 LeoLabs 對低地球軌道上20,000多個物體的數位展示。

It illustrates satellites, rocket bodies, and debris that can reach speeds of 18,000 miles per hour.

它展示了時速可達 18000 英里的衛星、火箭體和碎片。

Back in the 80s and the 90s were the bigger, the better.

Those things have come up and they're slowly filtering their way down.

這些事情已經出現，並在慢慢向下滲透。

Based on the altitude of rocket bodies in orbit, Monom expects 32 to re-enter the atmosphere in the next year, and a total of 270 in the next 50 years.

根據在軌火箭體的高度，莫諾姆公司預計明年將有 32 個火箭體重返大氣層，未來 50 年內將有 270 個火箭體重返大氣層。

We're talking about bodies which could be 3, 4, 5, 6 tonnes, and a significant part of their mass will survive intact to the Earth's surface.

我們談論的是重達 3 噸、4 噸、5 噸、6 噸的物體，其質量的很大一部分將完好無損地到達地球表面。

It could break up into different pieces and scatter over a larger area.

它可能分解成不同的碎片，散落在更大的範圍內。

Recent uncontrolled Chinese rocket stage re-entries have drawn criticism from international space agencies.

最近，中國失控的火箭級再入大氣層引起了國際太空機構的責備。

In 2022, a roughly 22-tonne Long March 5B rocket made an uncontrolled descent and broke up with debris landing near the Philippines.

2022 年，一枚重約 22 噸的長征 5B 火箭失控墜落，碎片散落在菲律賓附近。

NASA's administrator at the time, Bill Nelson, said the debris posed significant risk of loss of life and property.

NASA 當時的局長比爾-納爾遜（Bill Nelson）說，這些碎片造成了重大的生命和財產損失風險。

Months later, another Long March 5B rocket stage made an uncontrolled re-entry, prompting Spain to briefly close a roughly 120-mile-wide strip of its commercial airspace, delaying hundreds of flights.

幾個月後，另一枚長征五號乙火箭在失控的情況下重返大氣層，促使西班牙短暫關閉了約 120 英里寬的商業空域，導致數百架班機延誤。

It just shows we are not prepared, really, for the problem.

這只能說明我們還沒有做好準備，真的，我們還沒有準備好應對這個問題。

So these kind of actions are taken because people want to be safe, and the right answer is still to be found.

是以採取這些行動是因為人們希望安全，而正確的答案仍有待找到。

Last year, controlled re-entries outnumbered uncontrolled ones for the first time, driven largely by increased awareness of space debris hazards and wider adoption of mitigation measures.

去年，有控制的重返首次超過了無控制的重返，這主要是由於人們對太空碎片危害的認識有所提高，並更廣泛地採取了減緩措施。

We should not forget that the majority of the problem that we have now is a result of the action of the past, which was not so much private, which was more governmental-driven.

我們不應忘記，我們現在面臨的大部分問題都是過去的行動造成的，而過去的行動與其說是私人的，不如說是政府主導的。

One of the proposed solutions is active debris removal.

建議的解決方案之一是主動清除碎片。

Planned for launch in 2028, the ClearSpace-1 mission is the European Space Agency's bid to capture and safely de-orbit a derelict object.

計劃於 2028 年發射的 ClearSpace-1 任務是歐洲航空局捕獲一個廢棄物體並使其安全脫離軌道的努力。

If you are able to rendezvous and capture another object in space, you could refuel it, or you could repair it, or you could extend the life of a mission.

如果你能夠在太空中會合並捕獲另一個物體，你就可以為它加油，或者對它進行維修，或者延長任務的壽命。

That would be cheaper compared to launching a new spacecraft.

這比發射一個新的太空船要便宜得多。

But until these new methods come online, a question remains whether investment in mitigation efforts and the technology will advance as fast as the risks posed by an increasingly crowded orbit.

但是，在這些新方法投入使用之前，對減災工作和技術的投資是否能像日益擁擠的軌道所帶來的風險那樣快速發展，仍然是一個問題。