阿尔忒弥斯1号的疯狂之旅：英语精读讲义

This is the Artemis 1 mission leaving Earth and heading for the Moon.

这是 Artemis 1 任务离开地球前往月球的画面。

This spacecraft left Earth in the same way that all spacecraft leave.

它的离地方式与所有航天器一样。

But watch what happens when it gets close to the Moon.

但看看当它靠近月球时会发生什么。

The Orion capsule is sent on a crazy trajectory,

Orion 飞船进入了一条疯狂的轨道，

leaping ahead of the Moon,

冲在月球前面，

falling behind,

落后于月球，

and then being thrown back to Earth.

然后又被甩回地球。

What's even crazier is that this journey took 26 days to complete. 表達脈絡

更疯狂的是，这趟旅程花了整整 26 天才完成。

Compare this to the Apollo 8 journey, 表達脈絡

对比 Apollo 8 的旅程，

which only took 6 days to complete and followed a much simpler route.

它只花了 6 天时间，且路线简单得多。

So why didn't Artemis just do this?

那么为什么 Artemis 不直接这么做呢？

Getting to the Moon is no easy task. 短語搭配

登月绝非易事。

It takes an enormous amount of energy to get there.

到达月球需要消耗巨大的能量。

In fact,

事实上，

it takes more energy to land on the Moon than it does to land on Mars, 語法

登陆月球所需的能量甚至比登陆火星还要多，

despite the Moon being 500 times closer. 語法

尽管月球比火星近了 500 倍。

The goal with Artemis 1 was to send the Orion capsule around the Moon and test out all of its systems. 短語動詞

Artemis 1 的目标是将 Orion 飞船送入绕月轨道，并测试其所有系统。

The goal of the Apollo missions was to land humans on the Moon and return them to Earth.

而 Apollo 任务的目标是将人类送上月球并安全返回地球。

This requires a lot more energy,

这需要多得多的能量，

which makes the Saturn V rocket even more impressive.

这也使得 Saturn V 火箭更加令人惊叹。

But the SLS is actually more powerful than the Saturn V.

但 SLS 实际上比 Saturn V 更强大。

So why did Artemis 1 need to take such a weird route to the Moon?

那么为什么 Artemis 1 需要走这样一条奇怪的路线前往月球呢？

In this video,

在本期视频中，

we're going to look at the incredible physics behind getting Artemis 1 to its unusual orbit around the Moon.

我们将探讨 Artemis 1 进入其不寻常绕月轨道背后不可思议的物理学原理。

We'll also be announcing the winner of the previous giveaway.

我们还将在视频中公布上期抽奖活动的获胜者。

So make sure you stick around to the end of the video. 短語動詞

所以一定要看到视频最后。

When planning your route to the Moon,

在规划登月路线时，

it all comes down to delta v, 習語

一切都取决于 delta v（速度增量），

which is basically how much the spacecraft has to change its velocity to complete its journey.

它基本上是指航天器在完成旅程时需要改变多少速度。

The delta v required for a specific route is the same for every rocket.

对每枚火箭来说，特定路线所需的 delta v 都是一样的。

Two completely different rockets traveling on the same route will require the same amount of delta v.

两枚完全不同的火箭走同一条路线，所需的 delta v 是一样的。

But it's how much energy you have to put in to get that delta v that really matters. 語法

但真正重要的是，为了获得这个 delta v 你需要投入多少能量。

This shows the delta v required for every stage of a typical Apollo mission to the Moon.

这里展示了典型 Apollo 登月任务各个阶段所需的 delta v。

The problem is any change in velocity requires fuel to be burned.

问题在于，任何速度的改变都需要燃烧燃料。

If your rocket is much heavier or its engines are less efficient,

如果你的火箭重得多或者引擎效率较低，

you will need to put in more energy to achieve the same delta v.

你就需要投入更多的能量来实现相同的 delta v。

Despite SLS being more powerful than the Saturn V,

尽管 SLS 比 Saturn V 更强大，

the delta v dramatically falls away when we compare the command modules. 短語動詞

但当我们比较指令舱时，delta v 却大幅下降了。

Although Orion is lighter than Apollo,

虽然 Orion 比 Apollo 轻，

it has less than half of the delta v.

但它的 delta v 还不到其一半。

This is because Artemis 1 went with a much roomier command module at the expense of a smaller service module. 習語

这是因为 Artemis 1 选择了一个更宽敞的指令舱，代价是服务舱变小了。

Apollo did the opposite and used a smaller command module with a much more capable service module with more thrust and propellant capacity.

Apollo 恰恰相反，它使用了较小的指令舱，搭配了性能更强、推力和燃料容量更大的服务舱。

This had a massive effect on delta v.

这对 delta v 产生了巨大影响。

But having such a small and lightweight command module meant that the life support systems could only support the crew for a total of 14 days.

但是，如此小巧轻便的指令舱意味着其生命维持系统只能支持宇航员 14 天的时间。

Because of this,

正因为如此，

the Apollo missions had no choice but to take the quickest route to the Moon. 短語搭配

Apollo 任务别无选择，只能走最快的路线前往月球。

This involved performing a long duration burn as soon as it arrived at the Moon to slow it down and place it into orbit. 用詞

这包括在到达月球时立即进行长时间点火以减速，从而将其送入轨道。

This took a lot of energy,

这消耗了大量能量，

but it meant that they could get into lunar orbit in just 3 days compared to 10 days for Artemis 1.

但这也意味着他们只需 3 天就能进入月球轨道，而 Artemis 1 则需要 10 天。

Orion simply didn't have the delta v to do this,

Orion 根本没有足够的 delta v 来实现这一点，

and so NASA had to do an amazing bit of planning to get to the Moon.

因此 NASA 必须制定一套令人惊叹的计划才能到达月球。

This brings me to the Omaze sponsor of today's video, 表達脈絡

这引出了我们今天视频的赞助商 Omaze，

Omaze.

Omaze。

Omaze gives people the chance to dream big and win once-in-a-lifetime prizes, 用詞

Omaze 让人们有机会怀揣大梦想，赢得一生一次的丰厚大奖，

all while helping non-profits to make our world a better place. 語法

同时也帮助非营利组织让我们的世界变得更美好。

Right now,

现在，

Omaze is giving you the chance to win a custom Tesla Model S Apex.

Omaze 为您提供赢取定制版 Tesla Model S Apex 的机会。

This Model S Plaid Edition is top of the line and loaded with cutting-edge technology from a 396-mile driving range 習語

这款 Model S Plaid 版是顶级配置，搭载了前沿技术，包括 396 英里的续航里程，

to a 0-to-60 time in less than 2 seconds.

以及不到 2 秒的百公里加速时间。

Sure, it may not be able to get you to space yet, 語法

当然，它可能还无法把你送上太空，

but it will certainly get you anywhere else you need to go in style. 習語

但它绝对能让你极其拉风地去到任何想去的地方。

Enter for your chance to win at omaze.com/primalspace

前往 omaze.com/primalspace 参与抽奖，

and support the Petersen Automotive Museum in developing new exhibits,

并支持 Petersen 汽车博物馆开发新展览、

events,

活动

and education programs.

及教育项目。

This experience closes on the 27th of January,

本次活动将于 1 月 27 日截止，

so enter today and help Omaze reach their goal of raising more than $1 billion in a single year.

所以今天就来参加吧，帮助 Omaze 实现一年内筹集超过 10 亿美元的目标。

In order for Orion to get to the Moon and stay for long enough, 語法

为了让 Orion 到达月球并停留足够长的时间，

NASA aimed for a distant retrograde orbit, 文化背景

NASA 将目标锁定在远距离逆行轨道，

which had never been done around the Moon until this year.

直到今年，还从未在月球周围实现过这种轨道。

This involves orbiting the Moon at a distance and moving in the opposite direction to the Moon's orbit around Earth.

这涉及到在较远距离绕月飞行，且方向与月球绕地球的轨道方向相反。

In this orbit,

在这条轨道上，

the spacecraft spends an equal amount of time at Lagrange points 1 and 2, 文化背景

航天器在拉格朗日点 1 和 2 停留的时间相等，

which help to keep the orbit balanced.

这有助于保持轨道的平衡。

This means that the spacecraft doesn't need to waste fuel in order to maintain its orbit.

这意味着航天器不需要为了维持轨道而浪费燃料。

In order to get to this orbit,

为了进入这条轨道，

a spacecraft could aim to meet the Moon here

航天器可以在这里与月球会合，

and perform a burn to slow itself down and complete the orbit.

然后点火减速，完成轨道切入。

This is called a direct insertion. 文化背景

这被称为直接切入。

That's what she said. 文化背景

正如那句玩笑话所说。

And is essentially what the Apollo missions did.

这基本上也是 Apollo 任务的做法。

However,

然而，

to save as much fuel as possible, 語法

为了尽可能节省燃料，

Orion went a different way.

Orion 采用了另一种方法。

Instead of aiming at a point 70,000 km from the Moon,

它没有瞄准距离月球 7 万公里的某一点，

Orion aimed for this point just 100 km above the lunar surface.

而是瞄准了距离月球表面仅 100 公里的这一点。

From here,

从这里，

Orion made use of a gravity assist to slow it down. 講解

Orion 利用重力辅助来进行减速。

Although most people think of gravity assists being used to accelerate an object, 表達脈絡

虽然大多数人认为重力辅助是用来让物体加速的，

the exact opposite can be done by approaching the Moon from a different side.

但如果从不同侧面靠近月球，就能达到完全相反的效果。

The Moon orbits the Earth counterclockwise.

月球以逆时针方向绕地球运行。

If Orion approached the Moon from this side,

如果 Orion 从这一侧靠近月球，

not only would the Moon's gravity pull it in, 語法

月球引力不仅会将其拉入，

but since the Moon is also moving away incredibly fast,

而且由于月球本身也在以极快的速度移动，

it would pull the spacecraft along and slingshot it at an even greater velocity. 用詞

它会拉着航天器一起运动，以更快的速度将其弹射出去。

If you approach the Moon from the other side,

如果你从另一侧靠近月球，

you end up traveling in the opposite direction to the Moon, 短語搭配

你的运动方向将与月球相反，

and so instead of increasing your speed,

所以这不仅不会增加你的速度，

it pulls against you and slows you down.

反而会拉扯你并让你减速。

This is exactly what Orion did,

这正是 Orion 的做法，

but this alone isn't enough to get into lunar orbit.

但仅靠这一点还不足以进入月球轨道。

When Orion reached the point of closest approach, 用詞

当 Orion 达到近月点时，

it fired up its engine to slow itself down even more. 短語動詞

它启动引擎让自己进一步减速。

This slowed it down just enough to enter into an elliptical orbit with an apoapsis of 70,000 km,

这使其速度恰好降至足以进入一条远月点为 7 万公里的椭圆轨道，

the exact height it was aiming for before.

这正是它之前瞄准的高度。

Since the gravity assist did most of the work, 習語

由于重力辅助完成了大部分工作，

Orion was able to save a huge amount of fuel.

Orion 能够节省大量燃料。

However,

然而，

Orion still hadn't reached its distant retrograde orbit,

Orion 仍未进入其远距离逆行轨道，

so it had to do one more burn in order to circularize its orbit. 用詞

因此它还需进行一次点火以实现轨道圆化。

It performed a burn once it reached its apoapsis to accelerate and raise its periapsis to 70,000 km. 用詞

在到达远月点时，它进行了一次点火加速，将近月点提高到了 7 万公里。

This got Orion into a distant retrograde orbit,

这使得 Orion 进入了远距离逆行轨道，

which meant it traveled much deeper into space than the Apollo missions.

这意味着它比 Apollo 任务进入了更深远的太空。

A single orbit of the Moon at this distance took 12 days,

在这个距离绕月飞行一圈需要 12 天，

and if NASA wanted to,

如果 NASA 愿意，

they had the option of extending it by another 12 days 短語搭配

他们也可以选择延长 12 天，

by simply staying around the Moon for another lap.

只需绕月球再飞行一圈即可。

This orbit was ideal for NASA,

这条轨道对 NASA 来说非常理想，

as it meant they could spend more time testing out Orion's systems.

因为这意味着他们有更多时间测试 Orion 的系统。

This trajectory may seem unusual at first,

这条轨道起初可能显得有些不寻常，

but when we look at it from the Moon's perspective, 短語搭配

但如果我们从月球的角度来看，

it starts to make a lot more sense 短語搭配

它就开始变得非常有意义了，

and we can see how the Moon captured Orion.

我们也可以看出月球是如何捕获 Orion 的。

It's even more interesting if we go back to Earth's perspective and take away the Moon.

如果我们回到地球的视角，并且忽略月球，那会更加有趣。

Technically, 表達脈絡

从技术上讲，

Orion was actually still just in an elliptical orbit around Earth,

Orion 其实仍然只是在绕地球的椭圆轨道上运行，

but because its orbital period was the same as the Moon,

但由于其轨道周期与月球相同，

it appeared to constantly swap sides.

看起来它似乎在不断地切换位置。

To get back to Earth,

为了返回地球，

Orion had to break free of the Moon's gravity. 短語動詞

Orion 必须摆脱月球引力的束缚。

This meant doing the clever gravity assist maneuver,

这意味着要进行同样巧妙的重力辅助机动，

but in reverse. 短語搭配

只是方向相反。

It slowed down so that it would come close to the lunar surface 語法

它减速以便靠近月球表面，

and then did a final burn,

然后进行了最后一次点火，

which sent it on a trajectory back to Earth. 短語搭配

这将其送入了返回地球的轨道。

The reason it waited to perform this final burn at its closest approach 語法

为什么它要等到近月点才执行这最后一次点火，

is due to the Oberth effect. 文化背景

是因为奥伯斯效应。

Even with the same amount of fuel on board, 語法

即便携带相同数量的燃料，

the rocket gains much more velocity by burning closer to the Moon

离月球越近，受到的引力越大，此时点火能使火箭获得多得多的速度。

when it's feeling the most amount of gravitational pull.

此时它正承受着最大的引力。

Imagine two moving walkways, 表達脈絡

想象两条自动人行道，

one moving slowly and one moving fast.

一条移动得很慢，一条移动得很快。

If someone walks down the slow one,

如果有人在慢的那条上走，

they will come off the end still moving quite slowly.

他们走到尽头时，速度依然很慢。

If someone walks on the fast one,

如果有人在快的那条上走，

they will come to the end at a significantly higher speed.

他们到达尽头时，速度会明显快得多。

Not only that, 表達脈絡

不仅如此，

they will achieve a higher delta v by using less energy

他们还能用更少的能量获得更高的 delta v，

since they have spent less time walking.

因为他们走路所花的时间更少。

When a spacecraft is at its closest approach,

当航天器处于近点时，

it's experiencing the highest amount of gravitational pull,

它正承受着最大的引力，

which speeds it up as if it were on the faster walkway. 語法

这使得它的速度加快，就像走在那条较快的自动人行道上一样。

These types of maneuvers are an incredibly important part of spaceflight.

这类机动是航天飞行中极其重要的一部分。

They allow humans to make the most incredible leap to the Moon,

它们让人类能够完成飞向月球的不可思议的壮举，

and with Orion,

而借助 Orion，

they will continue to pave the way for future astronauts. 習語

它们将继续为未来的宇航员铺平道路。

And now,

现在，

it's time to give away a Saturn V rocket. 短語動詞

是时候送出一枚 Saturn V 火箭模型了。

The winner of this Primal Space giveaway is Ben Bensen.

本次 Primal Space 抽奖活动的获奖者是 Ben Bensen。

Congratulations.

恭喜你！

But don't worry if you didn't win, 語氣意圖

如果你没中奖也别担心，

we'll be announcing yet another giveaway in the next video.

我们将在下期视频中公布另一场抽奖活动。

Thank you very much for watching

非常感谢您的观看，

and I'll see you in the next video.

我们下期视频再见。