旅行者号跨越150亿英里的软件更新：英语精读讲义

In 2015,

在2015年，

NASA put out a job posting looking for a software engineer with a specific set of skills. 短語搭配

NASA发布了一份招聘启事，寻找具备特定技能的软件工程师。

The person had to be an expert in FORTRAN and assembly,

这个人必须是FORTRAN和汇编语言的专家，

two programming languages from the '40s and '50s that most young graduates don't know.

这是大多数年轻毕业生都不了解的四五十年代的两门编程语言。

The job was to join the very small team of people working on the Voyager space probes.

这份工作是要加入负责旅行者号空间探测器的极小团队。

Incredibly,

令人难以置信的是，

both Voyagers still run on their original 50-year-old computers, 短語動詞

两艘旅行者号至今仍在运行它们原始的有50年历史的计算机，

which have just 70 kilobytes of memory.

这些计算机只有70千字节的内存。

It might not sound like much, 語法

听起来可能不多，

but it was enough to navigate both space probes through our solar system and make incredible discoveries along the way.

但它足以引导两艘探测器穿越我们的太阳系，并沿途做出惊人的发现。

Unsurprisingly,

不出所料，

things do go wrong with Voyager's computers. 語法

旅行者号的计算机确实会出故障。

Just last year,

就在去年，

Voyager 1 started sending back garbled telemetry data about its orientation in space. 用詞

旅行者1号开始传回关于其在太空中姿态的乱码遥测数据。

On top of that, 表達脈絡

除此之外，

the thrusters in charge of keeping Voyager pointing in the right direction were starting to show signs of fatigue. 習語

负责保持旅行者号指向正确方向的推进器开始出现老化迹象。

Every time the thrusters are used, 語法

每次使用推进器时，

tiny pieces of hydrazine fuel get stuck in the pipes.

都会有微小的肼燃料碎屑卡在管道中。

This has built up over time, 短語動詞

随着时间的推移，这些碎屑不断堆积，

causing blockages in the system.

导致系统堵塞。

Voyager is already on its backup thrusters,

旅行者号已经在使用备用推进器了，

and so if these failed, 語法

因此如果这些也失效了，

it would be the end for Voyager.

旅行者号的使命就将终结。

At a distance of 15 billion miles,

在150亿英里之外，

there is no way of clearing the tubes. 語法

没有任何办法可以清理管道。

But in order to slow down the buildup and fix the telemetry problem, 講解

但是为了减缓堵塞物的堆积并修复遥测问题，

the small team in charge of Voyager began writing a software update that would be sent across our universe to fix it.

负责旅行者号的小团队开始编写一份软件更新，将跨越宇宙发送过去以修复它。

There are three main computers on board Voyager.

旅行者号上搭载了三台主计算机。

The main computer controls all of the major instruments,

主计算机控制所有主要仪器，

maintains its health and temperature,

维持其健康状态和温度，

and also controls the other two computers.

同时也控制着另外两台计算机。

The second computer is in charge of Voyager's orientation,

第二台计算机负责旅行者号的姿态定向，

so it looks for predetermined reference points

因此它会寻找预定的参考点，

and fires the thrusters to keep Voyager's antenna pointing towards Earth. 語法

并点燃推进器以保持旅行者号的天线指向地球。

The third computer is in charge of storing and handling all of the scientific data and images taken by Voyager's instruments.

第三台计算机负责存储和处理旅行者号仪器拍摄和收集的所有科学数据与图像。

Voyager doesn't have an operating system,

旅行者号没有操作系统，

and any kind of programming language would take up too much space. 短語動詞

而且任何形式的编程语言都会占用太多空间。

But this isn't the first time Voyager has been updated. 語法

但这并不是旅行者号第一次进行更新。

At Neptune,

在海王星时，

the light was 900 times dimmer than it was at Earth. 語法

光线比地球上暗900倍。

So in order to take pictures,

因此为了拍照，

engineers had to reprogram the camera to take longer exposures. 用詞

工程师们不得不重新编程相机以进行更长时间的曝光。

Once it left Neptune,

一旦离开海王星，

NASA began shutting down things like the camera and various scientific instruments to save power. 短語動詞

NASA就开始关闭相机和各种科学仪器以节省电力。

But with just 70 kilobytes of memory on board its computer,

但是其计算机上只有70千字节的内存，

having lines of code for dead instruments was a waste of space. 語法

为已经停用的仪器保留代码是一种空间浪费。

And so the engineers completely rewrote Voyager's code and performed a software update to make sure it continued to live for the foreseeable future. 短語搭配

因此，工程师们完全重写了旅行者号的代码并执行了软件更新，以确保它在可预见的未来继续存活。

But how does NASA update such old hardware from 15 billion miles away? 表達脈絡

但是，NASA是如何从150亿英里外更新如此古老的硬件的呢？

To understand how difficult this is, 表達脈絡

要理解这有多困难，

we need to know how the software works on Voyager.

我们需要知道旅行者号上的软件是如何工作的。

Voyager runs the latest version of NordVPN.

旅行者号运行的是最新版本的NordVPN。

Not really. 語氣意圖

开玩笑的。

NordVPN wouldn't fit on Voyager's computers,

NordVPN装不进旅行者号的计算机里，

but if it did, 語法

但如果能装下，

it would do a great job of protecting Voyager from online threats.

它将会在保护旅行者号免受在线威胁方面做得非常出色。

Whenever you are connected to Wi-Fi,

每当你连接到Wi-Fi，

especially public Wi-Fi,

尤其是公共Wi-Fi时，

your data is constantly at risk from hackers.

你的数据经常面临黑客的威胁。

With NordVPN,

有了NordVPN，

you can become instantly protected with just a single click.

只需点击一下，你就能立即受到保护。

How many times have you gone to watch a YouTube video or Netflix series

有多少次你去看YouTube视频或Netflix剧集，

only to find it's blocked in your country? 語法

却发现它在你所在的国家/地区被屏蔽了？

With NordVPN,

有了NordVPN，

all you need to do is connect to one of the 5,000 servers, 語法

你只需要连接到其5000个服务器中的一个，

and suddenly all the content you've been missing will appear.

你一直错过的所有内容就会突然出现。

NordVPN has also launched Meshnet,

NordVPN还推出了Meshnet功能，

the safest way to connect to all of your devices,

这是连接你所有设备的最安全方式，

no matter where you are in the world.

无论你在世界的哪个角落。

It acts like a local area network

它就像一个局域网，

and creates a secure way to directly access things like personal servers and share files around the world.

并创建了一种安全的方式来直接访问个人服务器并在全球范围内共享文件。

NordVPN works on every major platform

NordVPN适用于所有主要平台，

and can be installed on up to six devices at one time.

并且可以同时安装在多达六台设备上。

To get NordVPN's 2-year plan plus 4 months for free,

要想免费获得NordVPN两年计划外加4个月的服务，

visit nordvpn.com/primalspace.

请访问 nordvpn.com/primalspace。

In order to do a software update on Voyager,

为了对旅行者号进行软件更新，

NASA needs to install the new code into its computers.

NASA需要将新代码安装到其计算机中。

Perhaps the coolest thing about Voyager's computers is the memory.

也许旅行者号计算机最酷的地方就是内存。

Each computer has its own plated wire memory,

每台计算机都有自己的镀线存储器，

which stores Voyager's code in its most basic form,

它以最基本的形式，即1和0，

ones and zeros.

存储旅行者号的代码。

This memory consists of a physical grid of wires and thin metal plates.

这种存储器由物理的导线网格和薄金属板组成。

Each intersection point can be thought of as a single bit of memory, 語法

每个交叉点可以被认为是一个单位的内存，

and it can store either a one or a zero.

它可以存储一个1或一个0。

By passing a current through one of the plates and a specific wire, 語法

通过让电流穿过其中一块金属板和特定导线，

it would create a magnetic field.

会产生一个磁场。

If the magnetic field is in this direction,

如果磁场是这个方向，

it is considered a zero.

就被认为是0。

If it goes in the opposite direction,

如果它是相反方向，

it's a one.

那就是1。

By passing a current in the opposite direction,

通过使电流反向通过，

it would change the direction of the magnetic field and flip the bit to a zero.

就会改变磁场的方向并将该位翻转为0。

By doing this for every point,

通过对每个点执行此操作，

you could save these ones and zeros into the memory.

你可以将这些1和0保存到内存中。

This design was a great choice at the time because it meant that even if the power went out, 語法

这个设计在当时是一个很好的选择，因为这意味着即使断电，

the ones and zeros would still be saved to the memory.

这些1和0依然会保存在内存中。

It also meant that each bit could be updated.

这也意味着每个位都可以被更新。

With just 70 kilobytes of total memory on board Voyager,

由于旅行者号上总共只有70千字节的内存，

the engineers have to be extremely efficient with their code.

工程师们必须让他们的代码极其高效。

Along with this basic machine code,

除了这种基本的机器代码外，

Voyager has its own pseudocode,

旅行者号还有自己的伪代码，

basically a series of shortcut commands that can be triggered to carry out repetitive tasks without taking up too much memory. 講解

基本上就是一系列快捷命令，可以被触发来执行重复性任务，而不会占用太多内存。

An interpreter on board the main computer reads the ones and zeros.

主计算机上的解释器读取这些1和0。

Once it comes across a predetermined code, 短語動詞

一旦它遇到预定的代码，

it initiates the pseudocode to carry out a command.

就会启动伪代码来执行命令。

This saves lots of memory and allows many tasks to be automated without writing out long lines of code. 語法

这节省了大量内存，并允许许多任务自动化，而无需编写冗长的代码行。

But the problem is that humans can't code in just ones and zeros,

但问题是，人类无法只用1和0来编写代码，

and so a more advanced language is needed to actually write the code for Voyager.

因此需要一种更高级的语言来实际为旅行者号编写代码。

On Earth,

在地球上，

Voyager's software was originally written in assembly language with a little bit of FORTRAN.

旅行者号的软件最初是用汇编语言和少量的FORTRAN编写的。

Assembly is a very simple language that can be understood by humans,

汇编是一种人类能看懂的非常简单的语言，

but is much closer to the basic ones and zeros of machine language.

但它更接近机器语言基础的1和0。

Once the code is complete,

代码一旦完成，

it gets compiled into machine code, 語法

就会被编译成机器代码，

which can be sent to Voyager using the Deep Space Network. 文化背景

可以通过深空网络发送给旅行者号。

The data is sent to Voyager at a rate of 16 bits per second, 短語搭配

数据以每秒16比特的速率发送给旅行者号，

and it takes almost an entire day to actually reach Voyager. 語法

这几乎需要一整天的时间才能实际送达旅行者号。

The computers on board Voyager are interrupt-driven. 用詞

旅行者号上的计算机是中断驱动的。

This means that the software goes through its usual list of instructions until it gets interrupted. 講解

这意味着软件会浏览其常规的指令列表，直到被中断为止。

When an update is sent to Voyager,

当更新发送给旅行者号时，

it carries an interrupt signal.

它带有中断信号。

When Voyager receives this,

当旅行者号收到这个信号时，

it tells the main computer to stop what it's doing

它会告诉主计算机停止正在做的事情，

and instead work on the update instructions.

转而去处理更新指令。

It then unloads the new code into the memory,

然后它将新代码加载到内存中，

flipping all the bits to their new position.

把所有的位翻转到它们的新位置。

The code is then read through to check that everything is correct, 短語動詞

随后将读取代码以检查一切是否正确，

and then the main computer kicks it into gear and returns to normal operations. 習語

接着主计算机启动它并恢复正常运行。

Over the years,

多年来，

Voyager has received a long list of updates and patches to fix and improve how it operates.

旅行者号收到了一长串更新和补丁，以修复和改进其运行方式。

In 1995,

在1995年，

an update was written that would basically restart certain components if they failed.

编写了一个更新，基本上是在某些组件发生故障时重启它们。

In 2014,

在2014年，

some 20 years after the code was written, 用詞

也就是代码写完大约20年后，

this code saved Voyager 1 when a piece of hardware malfunctioned.

当一个硬件出现故障时，这段代码拯救了旅行者1号。

In 2010,

在2010年，

a single bit of Voyager's memory was flipped,

旅行者号内存中的一位被翻转，

changing a zero to a one.

把一个0变成了1。

This caused computers to lose sync with each other, 短語搭配

这导致计算机相互失去同步，

and the commands started happening 2 1/2 hours later than expected.

指令的执行比预期晚了两个半小时。

A software update was sent up to flip the faulty bit back into its correct position.

于是发送了软件更新，以将故障的位翻转回正确的位置。

It's amazing stories like these that have allowed these iconic space probes to survive almost 50 years in space. 語法

正是这些惊人的故事，使得这些标志性的空间探测器在太空中存活了近50年。

It's incredible that the physical wires, transistors, and hardware on board Voyager's computers

令人难以置信的是，旅行者号计算机上的物理电线、晶体管和硬件，

are still operating as intended after all this time. 短語搭配

在经历了这么长的时间后，仍然能按预期运行。

And now for the Primal Space giveaway.

现在到了Primal Space的抽奖环节。

The winner of the previous giveaway is Yasmine.

上一次抽奖的获胜者是Yasmine。

Congratulations.

恭喜。

In the next video,

在下个视频中，

we'll be giving away this Primal Space designed Voyager poster.

我们将送出这张由Primal Space设计的旅行者号海报。

All you need to do is sign up at the link below,

你只需要在下方链接注册，

like the video,

给视频点赞，

and leave a comment

并留下一条评论，

saying where you would send a Voyager 3 if it launched today.

说说如果今天发射旅行者3号，你会把它送到哪里。

Thank you very much for watching,

非常感谢观看，

and I'll see you in the next video.

我们下个视频见。