Why is everyone fighting over these tiny spots of space? - Fabio Pacucci

翻译人员: gigide Hulu 校对人员: Jacky He

Since the launch of the first artificial satellite in 1957,

自 1957 年第一颗 人造卫星发射以来，

governments, companies, and research institutions

政府、公司和研究机构

have been planting flags among the stars.

一直在给行星们添上旗帜。

But while it might seem like there's plenty of room in this vast expanse,

虽然宇宙空间不可估量，

some pieces of celestial real estate are more valuable than others.

有些天文位置比其他更有价值。

Each of these dots is a Lagrange point,

这其中每一个点都是拉格朗日点 (Lagrange point)，

and as far as human space exploration is concerned,

而对人类太空探索而言，

they may be the most important places in our solar system.

它们可能是我们 太阳系中最重要的地点。

Named after the 18th century mathematician who deduced their positions,

拉格朗日点为推导出其位置的 18 世纪数学家而命名，

Lagrange points are rare places of equilibrium

它在我们不断运动的宇宙中，

in our constantly shifting universe.

是罕见的平衡点。

All celestial bodies exert a gravitational force on nearby objects,

所有天体会对附近的物体施加引力，

pulling them in and out of orbits.

将它们拉入和拉出轨道。

And gravity acts alongside several apparent forces

重力与几种表观力一起作用，

to determine what those orbits look like.

确定了这些轨道形状。

However, Lagrange points are places where all these forces balance out.

但是，拉格朗日点是所有 这些力平衡的地方。

So if we place a relatively low mass object here,

因此，如果我们在这里放置一个 质量相对较低的物体，

it will maintain a constant distance from the massive bodies pulling on it.

它将与吸引它的巨大天体 保持恒定的距离。

Essentially, Lagrange points are celestial parking spaces—

从本质上讲，拉格朗日点 像天体停车位——

once an object is there, it requires little to no energy to stay put.

一旦物体在那里，它几乎 不需要任何能量便可留在原地。

So whenever humans want to keep an object in one place for a long time

因此，当人类希望不消耗大量燃料

without using tons of fuel,

将物体长时间保留在一个地方时，

it needs to be orbiting a Lagrange point.

它得绕着拉格朗日点运行。

However, there are only so many of these parking spots.

但是，停车位只有那么多。

Pairs of massive bodies in our solar system

太阳系中每对大型天体

generate sets of five Lagrange points.

会产生五个拉格朗日点。

This means our Sun has five points with every planet,

这意味着我们的太阳与 每个行星都有五个点，

and our planets have five points with each of their moons.

而我们的行星与 各颗卫星也有五个点。

Adding these up, there are over 1,000 Lagrange points in our solar system—

加起来我们太阳系中的 拉格朗日点超过 1,000 个，

but only a few are useful for human purposes.

但只有少数对人类有用。

Many are in locations that are too difficult to reach

许多点的位置难以到达，

or simply not very useful.

或是用处不大。

And for reasons we'll explain in a bit, many others are unstable.

许多点也不稳定， 这我们会稍后解释。

Currently, only two of these points are heavily used by humans.

目前，其中只有两个点 被人类广泛使用。

But we’ll likely use many more in the future—

但在未来我们可能会 使用更多的点——

making these limited points exclusive real estate.

把这些有限的点转成特权地点。

Which begs the question: what exactly should we park in them?

这就引出了一个问题： 我们到底应该在里面停什么？

That answer depends on where each point is.

这个答案 取决于每个点在哪里。

Consider the five Lagrange points generated by the Sun and the Earth.

以太阳和地球产生的 五个拉格朗日点为例。

L1 is located inside Earth's orbit,

L1 位于地球轨道内，

about 1.5 million kilometers away from the planet.

距离地球约 150 万公里。

With this panoramic view of the Sun, unobstructed by Earth’s shadow,

L1 不被地球遮挡， 可见到太阳全景，

L1 is the perfect place for solar-observing satellites.

是太阳观测卫星的理想地点。

L2 is at the same distance from Earth but outside its orbit

L2 与地球的距离相同， 但在轨道之外，

and shielded from the Sun,

在太阳的阴影中，

making it the perfect spot to observe outer space.

使其成为观测外部太空的理想地点。

In 2022, the James Webb Space Telescope went online here,

2022 年，詹姆斯·韦伯 太空望远镜在这里部署；

in a spot where the Sun and Earth only occupy a tiny fraction of the sky.

在这里，太阳和地球 只占天空的很小一块。

L3 is in a particularly mysterious location

L3 位于一个特别神秘的地方，

that can never be directly observed from Earth’s surface.

永远无法从地球表面观察到。

This has made L3 a frequent locale in science fiction,

这使得 L3 在 科幻小说中经常出现，

though it hasn’t offered much use to scientists yet.

尽管它对科学家们用处不大。

L4 and L5, however, are a bit different from their siblings.

而 L4 和 L5 和其余的略有不同。

In every set of five, the first three Lagrange points are slightly unstable.

在每五个点中， 前三个拉格朗日点略微不稳定。

This means objects will slowly drift away from them,

这意味着物体会慢慢地远离它们，

though keeping what we’ve parked there in place is still energetically cheap.

但使我们停在那里的东西 留在原地并非难事。

The stability of L4 and L5, however, varies from set to set.

而 L4 与 L5 的稳定性 取决于天体对。

If the heavier of the two bodies generating the points

如果两个天体中较重的天体

has less than 25 times the mass of the lighter body,

质量不足较轻天体的 25 倍，

these points are too unstable to park things in.

这些点就会不稳定， 物体无法在其中停靠。

However, if the heavier body is massive enough— like it is in Sun-Earth set—

但是，如果较重的物体足够大， 如太阳、地球这组天体，

then the relevant forces will always return objects

那么这些力会使

to these equilibrium points,

物体待在平衡点，

making them our most stable parking spots.

使它们成为最稳定的停车点。

That’s why points like these naturally accumulate space objects,

这便是为什么类似的点 会积聚太空物体的原因，

such as the Sun-Jupiter set’s L4 and L5, which host thousands of asteroids.

例如太阳、木星的 L4 和 L5， 聚集着上千个小行星。

Every Lagrange point in our solar system has its quirks.

太阳系中的每个 拉格朗日点都有其特点。

Some might be perfect for scavenging construction materials

有些可能非常适合

from drifting asteroids.

从漂移的小行星中开采建筑材料。

Others might make ideal gas stations for ships headed to deep space,

其他可以成为前往深空中 飞船的理想加油站，

or even host entire human colonies.

甚至容纳完整的人类殖民地。

These points are already home to advanced technological achievements,

这些地点已经存在着先进技术设备，

but soon, they could become our stepping stones to the stars.

但不久，它们也许成为 我们通往星空的基地。