A delivery from the moon

November 8, 2022

The 14th Zhuhai Air Show is here as scheduled

J-20, Y-20, C919, etc.

Various large aircraft made stunning appearances

Its mass often reaches tens of tons or even hundreds of tons.

( Please watch in horizontal mode , aerial photography of Zhuhai Air Show, photographer @盘家灿)

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at the same time

On display

There is also an "inconspicuous" exhibit

Its mass is only 0.049 grams

About the weight of a grain of wheat

But the value is totally immeasurable

Because it is

Our Chang'e 5 flew over 760,000 kilometers

A "delivery" brought back from the moon

It is

Lunar Soil

(Lunar soil samples on display at the National Space Administration exhibition area at the Zhuhai Air Show, photographer @盘家灿, tagged @刘志鹏/Planetary Research Institute)

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Just 2 years ago

After 23 days of expedition

Chang'e 5 carries 1,731 grams of lunar samples

Return to Earth

Yes

1731 g

Equivalent to the weight of 10 apples

But so far there has been nothing like this

More difficult, more complex, more glorious

The mission of "express delivery"

(The Long March 5 rocket carrying the Chang'e 5 probe was launched into space, forming a beam of light that shot straight into the sky. Photographer @郭煜坤)

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You know, 40 years ago

The United States once gave us lunar samples

It weighs only 1 gram

Chinese scientists need research samples

But only 0.5 grams of it can be shared

today

1731g sample

Already allocated to

67 domestic research institutions conduct scientific research

Help Chinese scientists embark on a new journey of interstellar exploration

(Lunar sample No. 001 exhibited at the National Museum, sample weight is 100 grams, photographer @张本志)

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Behind this

It's actually a journey across the stars.

Great Relay

01

A relay across 760,000 kilometers

December 17, 2020

Siziwang Banner, Inner Mongolia

In the deserted Gobi

Only the chilly wind lingers for a long time

Until a loud noise broke through the night sky

A bell-shaped metal container

Riding a giant parachute

Back to the surface

It is black and scarred.

Like a hero returning from battle

Surrounded by the enthusiasm of the people who came quickly

(Chang'e 5 returner returns to the scene, picture source: @National Space Administration)

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To avoid catching a cold

People even posted a

Full of warm baby

(The most advanced equipment often only requires the simplest way to keep warm. At that time, the night temperature in Inner Mongolia reached minus 30 degrees Celsius. The staff was worried that the remaining propellant in the returner would be difficult to discharge after freezing, so they covered it with hot packs for temporary warmth. Photographer @李淑姮)

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It successfully brought back the Chinese people's own

1731 grams of lunar soil

But the "comrades" who went out with it

But there is no chance to return to home on Earth

(December 17, 2020, Chang'e 5 returner air transport scene, photographer @崔建平)

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These include

Lander responsible for lunar surface sampling

Ascender completing sample transfer

The orbiter responsible for round-trip transportation

They and the return vehicle that escorted the lunar soil back to the surface

Together they formed Chang'e 5

The joint relay completed the

A round trip distance of 760,000 kilometers

(Structure diagram of Chang'e 5, drawn by @李炎&王申雯/Planetary Research Institute)

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As the most complex structure in China

The largest lunar probe

It is 7.2 meters high and weighs 8.2 tons.

Equivalent to the weight of nearly 7 cars

And to send such a huge thing into orbit

China's most powerful rocket must be used

then

November 24, 2020 at 4:30 AM

Long March 5 carrier rocket

Soaring into the air with a huge roar

A space relay officially begins

(The Long March 5 carrier rocket cuts through the night sky with its bright tail flame, photographer @陈肖&肖海林)

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36 minutes later

At an altitude of 300 kilometers above the earth's surface

"Long March 5" and "Chang'e 5" bid farewell

(The separation of Chang'e 5 and Long March 5, video source: documentary "Our Journey")

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And Chang'e 5 will continue its journey

After 5 days of non-stop flying

A 380,000-kilometer trek

Finally reached the moon

Become a satellite orbiting the moon

Afterwards

The expedition was divided into two groups.

One of the roads is

Lunar Surface Sampling Team

It consists of a lander and an ascender.

After two decelerations, they

Descend to 15 kilometers above the lunar surface

Next

29 engines

Start in order, adjust posture, slow down and descend

7 landing sensors

Real-time shooting, calculation analysis, and obstacle avoidance

Can you land successfully?

Victory or defeat depends on this one move

(Sketch of the Chang'e 5 landing process, drawn by @李炎&王申雯/Planetary Research Institute)

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finally

14 minutes later

The lander successfully landed on the moon!

Although at this time

There is silence all around it.

But 380,000 kilometers away on Earth

People were already cheering and excited.

(The picture of people in the command hall applauding when the Chang'e 5 returner successfully landed in Siziwang Banner, Inner Mongolia, is not the scene when Chang'e 5 landed on the moon. It is just for reference. Photographer @张高翔)

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However

The lander's mission is not over yet

After a short inspection and rest

It immediately wields its drill and shovel

Two-pronged approach

First, use a drill to drill deep beneath the lunar surface to obtain deep samples.

Then use a shovel to scoop up surface samples from the moon

After 19 hours of sampling

The precious lunar soil was sealed in the sample container.

(Sampling diagram of Chang'e 5 lander, drawn by @李炎&王申雯/Planetary Research Institute)

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And after this

It will pass the task to the next team member.

Ascender

I will stay on the moon forever.

Continue scientific exploration

This ascender

Will leave the lunar surface with lunar samples

But it didn't take off immediately.

But quietly waiting

Until more than ten hours later

It consists of an orbiter and a returner.

Space Transport Team

Passing above it

The ascender ignites immediately and soars into the sky

(Sketch of the Chang'e-5 ascender taking off from the lunar surface, courtesy of @王申雯&李炎/Planetary Research Institute)

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They are one big and one small, one in front and one behind, one chasing and one catching up.

The distance also changed from 50 kilometers to 100 meters

50 meters

10 meters

5 meters

0.5m

At the moment when we are close to each other

The "space transport team" in the rear

Open your "arms" and hold the ascender firmly

And take the sample into your "arms"

(Chang'e 5 rendezvous and docking diagram, source: @National Space Administration, marked with @王申雯/Planetary Research Institute)

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Afterwards

This space transport team

Will fly 380,000 kilometers again with lunar soil

Return to Earth

The ascender that completed its mission

I will watch their backs

Crashed on the moon and disappeared

But they have no time to grieve

5 days later

The space transport team arrives

5000 km above the Earth's surface

The orbiter's mission also ended.

The last leg of the mission

It will be completed by the returner alone

(Showing the separation of Chang'e 5 orbiter and returner, video source: Documentary "Flying to the Moon" Season 2)

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But

When the returner arrives

At the edge of the atmosphere 120 km above the surface

Flying speed up to 10.6km/s

If you dive directly into the atmosphere

Will generate a temperature of more than 2000℃

Very easy to damage the structure, fail at the last moment

therefore

Designed by scientists

This returner

Through a " skipping water " method

Entered the atmosphere twice

This reduces the speed to a controllable range

(Schematic diagram of the reentry of the Chang'e 5 returner, drawn by @王申雯&李炎/Planetary Research Institute)

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at last

The scene at the beginning of the article is staged

It took 23 days and flew 760,000 kilometers

The lunar expedition

In front of the whole world, a

The most exciting interstellar relay in China's space history

( Please watch in horizontal mode , the 11 flight phases of Chang'e 5 are shown here. Map by @王申雯&李炎/Planetary Research Institute)

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But this success was no accident.

Because from a broader perspective

This interstellar relay

It has been going on for 17 years

02

A relay that spans 17 years

Back to 2003

When the first Chinese astronaut Yang Liwei

Under the attention of the people of the country

When successfully entering space

China's lunar exploration

Still in the long argumentation of nearly 10 years

Not yet taken the first step

Until 2004

The Chang'e Project is finally launched

(The Chang'e-5 probe and the Long March-5 rocket are assembled. The Chinese lunar exploration logo in the center of the picture means "above the moon". A full moon is outlined with Chinese calligraphy strokes, and a pair of footprints are stepped on it, symbolizing the ultimate dream of the lunar exploration project. Photographer @史晓)

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But the world at that time

After a fierce space race

There are more than 100 probes heading for the moon

As early as 1969, the United States

The first manned lunar landing

(Summary of human lunar exploration situation, map by @王申雯/Planetary Research Institute)

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Looking back at China at that time

We don't have rockets powerful enough.

The farthest satellite

About 36,000 kilometers from the surface

Only 1/10 of the average distance between the Earth and the Moon

(The Long March 3A carrier rocket had successfully sent artificial satellites into geosynchronous orbit at an altitude of about 36,000 kilometers many times at that time. It was known as the "gold medal rocket", but it had never launched a lunar exploration satellite. Image source: @People's Vision)

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We do not have a complete measurement and control network

If the satellite cannot be accurately controlled

"A small mistake can lead to a big error"

(Yuanwang-3 survey ship. At that time, my country had built a space tracking and control network with Xi'an Satellite Tracking and Control Center as the hub, more than 10 fixed platforms, mobile tracking and control stations and Yuanwang survey ship as the backbone. However, it was mainly used for the tracking and control of various earth satellites and manned spaceflight. Most of them were no more than 42,000 kilometers from the ground, while the lunar satellite was up to 440,000 kilometers from the ground, which is more than 10 times the distance from the ground to the geosynchronous orbit satellite. Image source: China Satellite Maritime Tracking and Control Department)

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We haven't even

Specially designed lunar probe

China started almost from scratch

How can we fly between the earth and the moon?

What about 380,000 kilometers?

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Fly! Fly over!

No rocket powerful enough

Scientists have designed a

Unique lunar orbit

Right now

First, use a rocket to send the satellite to a lower orbit

Then find the right time to accelerate the satellite multiple times

It can be like a " slingshot "

Let the satellite escape the earth's gravity

Fly to the Moon

After being captured by the moon's gravity

Reuse the engine to slow down and descend

Until it reaches the planned track

(Sketch of Chang'e-1's orbit, courtesy of Liu Zhipeng/Institute of Planetary Research)

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No perfect measurement and control network

We introduced the

Radio telescope systems

Jointly achieve lunar tracking and control 380,000 kilometers away

(Beijing Miyun 50m radio telescope and meteor in the same frame. This telescope was newly built to complete the lunar exploration mission. It was the largest antenna system in China at that time. Photographer @孙业林)

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No dedicated lunar probe

We are based on the earth satellite Dongfanghong 3

Chang'e -1

It can not only

Ultra-low temperature and high radiation in space environment

Complete a long-haul flight

You can also use a number of scientific detection instruments

Observing the Moon

(Chang'e-1 full moon image, with a resolution of 120 meters, was the clearest and most complete full moon image published in the world at that time. Photographer: @嫦娥一号, map @陈志浩&王申雯/Planetary Research Institute)

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that's all

After more than three years of preparation

November 5, 2007

12 days after Chang'e-1 departed from Earth

Successfully reached the moon

Became China's first lunar satellite

(On October 24, 2007, the Long March 3A launched the Chang'e 1 lunar exploration satellite. Photographer: Cui Jianping)

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Since then

The Chang'e era officially begins

But this is just the first step

Next we need to implement

Lunar landing

②

Land! Land!

This is the most accurate

Full Moon Image

It is so detailed that the smallest structure is 7 meters

Still clearly visible

(Partial comparison of 7m and 120m resolution full moon images, photographer @Chang'e 1&Chang'e 2, map @Wang Shenwen&Chen Zhihao/Planetary Research Institute)

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It is composed of 746 photos of the moon.

The people who took these photos

It is our Chang'e 2

Different from Chang'e 1's "slingshot"

Thanks to the improvement of rocket capacity

and more precise track design

Chang'e 2 can be like a " javelin thrower "

Flying directly from Earth to the Moon

(Comparison of the orbits of Chang'e 2 and Chang'e 1, courtesy of Liu Zhipeng/Planetary Research Institute)

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But taking a full moon picture

But it is not its most important mission

After arriving on the moon

Chang'e 2 will continue to brake and slow down

Up to 15 kilometers above the lunar surface

So close to the moon

To do everything possible

A place called " Hongwan "

Take in the view

Because this is

Chang'e 3's planned landing area

(Sketch of the Chang'e-3 landing area, which is located in the Moon's Rainbow Bay region. On October 5, 2015, the International Astronomical Union (IAU) approved the naming of the area around the Chang'e-3 probe landing site as "Guanghan Palace", and the three nearby impact craters as "Ziwei", "Taiwei" and "Tianshi" respectively. Map by @王申雯/Planetary Research Institute)

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Chang'e 2 completed its exploration

Fly away from the moon without looking back

But the information it returns

Chang'e 3, which is actually responsible for the landing mission

Successfully embarked on the journey

Compared with the "predecessors" such as No. 1 and No. 2

It is no longer a satellite.

Instead, the lander and the lunar rover

Moon landing robot

(Structure diagram of Chang'e 3, drawn by @李炎&王申雯/Planetary Research Institute)

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Its flight trajectory is also more efficient

Only 2 brakes

You can reach the sky above Hongwan

Waiting for lunar landing

(Comparison of the orbits of Chang'e 3 and Chang'e 2, drawn by Liu Zhipeng/Planetary Research Institute)

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December 14, 2013 20:59:52

Once the landing command is given from Earth,

Chang'e 3 orbiting the moon

Then start the engine under the body

Start to decelerate and descend

3 km from the lunar surface

Flanker engine start

Quickly complete posture adjustment

2.4 km from Moon Surface

Sensors throughout the body work

Descending while judging the lunar surface

Avoid large obstacles

100 meters from the lunar surface

Engine thrust reverses gravity

Make the probe hover for 16 seconds

And in these short 16 seconds

The detector must accurately detect obstacles

Find a flat landing spot

Then continue to slow down and dodge obstacles

Until 3 meters from the lunar surface

Probe shuts down engine

Free Fall

4 retractable landing legs

Landing steadily on the lunar surface

This moment

China has become

The world's third

The country that independently achieved a soft landing on the moon

(Sketch of Chang'e 3 landing on the moon, drawn by @刘志鹏&李炎/Planetary Research Institute)

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In addition to landing

Chang'e 3 also returned the " Jade Rabbit "

Bringing back the moon

This is a lunar rover that can patrol the lunar surface.

Although it advanced more than 100 meters

Due to the complex lunar environment

Cannot move further

But it still persists

972 days on the lunar surface

3 months of service far exceeding expectations

(The lunar rover "Yutu" released by the Chang'e 3 probe, photographer @Chang'e 3 Lander, picture source @National Space Administration)

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final

On the last night of July 2016

Yutu has exceeded its mission targets

Stopped working

This "rabbit who has seen the most stars"

Saying final farewell to humanity

Then he fell into an endless sleep

(The Weibo post of "Lunar Rover Yutu" stopped forever on July 31, 2016, but even today, six years later, many netizens still leave comments on this Weibo every day. The base image comes from @POCKN, and the map is made by @王申雯/Planetary Research Institute)

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but

The exploration has not stopped

The second rabbit is about to set off

Continue to fulfill unfulfilled dreams

③

Go ahead! Go ahead!

Took over the mission

Yutu-2

As of July 5, 2022

It has traveled on the moon

1239.88m

More importantly

It and the Chang'e 4 that carried it

Not only did it make up for the regret of Yutu

It also achieved

First exploration of the far side of the moon

(Distribution of lunar probe landing sites, drawn by @陈志浩&王申雯/Planetary Research Institute)

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Why is it so difficult to explore the far side of the moon?

This is because of the effect of " tidal locking ".

The moon's rotation and revolution periods are the same

Only the "front" can face the earth

This means

People on Earth

You can never see the "far side" of the moon

It is also unable to communicate with the detector on the back

(Tidal locking is a diagram of the gravitational interaction between two celestial bodies that causes the rotation of the celestial bodies to slow down, and one celestial body always faces the same side of the other celestial body. Map by @郑伯容&王申雯/Planetary Research Institute)

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In order to overcome this problem

Chinese scientists

Between the Earth and the far side of the moon

Built an interstellar bridge

The Queqiao relay satellite debuts

It runs on a special track

Not only can it connect the far side of the moon and the earth at the same time

Very little energy is required

(Schematic diagram of the Queqiao relay satellite, drawn by Liu Zhipeng & Li Yan/Planetary Research Institute)

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With its blessing

January 3, 2019

Chang'e 4 landed successfully

Expanding the human footprint to

The distant and mysterious far side of the moon

Less than two years later

Chang'e 5's round trip was a success

This marks China's fifth success in the fifth lunar exploration mission.

“Orbiting the Moon, Landing on the Moon, and Returning”

All completed

A long relay that lasted 17 years

The curtain falls

But this

Is that the whole story?

03

The “invisible” relay

Back to July 2, 2017

On the Qishui Bay beach in Wenchang, Hainan

Gathering tourists from all over the world

Everyone is waiting

Waiting for a rocket launch after nightfall

19:23:23

Long March 5 Y2 rocket

Successfully ignited and took off

But only 346 seconds later

The rocket suddenly deviated from its course and lost control.

Then it plunged into the Pacific Ocean

Star and rocket destroyed

(On July 2, 2017, the crowd watched the launch of the Long March 5 Yao 2 rocket. Photographer: @陈肖&肖海林)

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The successful launch of the Long March 5

The second launch failed

This makes the Chang'e Project move forward

I suddenly pressed the pause button.

Chang'e 5 was originally scheduled to be launched in November of the same year.

We can only wait for the "Fat Five" to be ready again

And this wait lasted three years

(On November 24, 2020, the Long March 5 before the launch of the Chang'e 5 mission. Due to its large size, it was nicknamed "Fat Five". Photographer @陈肖&肖海林)

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But this is aerospace

It has always been a system project.

"Chang'e Flying to the Moon" is no exception

Behind this

We need not only a

Launch vehicle system

Still need

Assembling, testing, and launching rockets

Launch Site System

(The vertical transfer of the Long March 5 rocket at the Wenchang Space Launch Center in Hainan Province, photographer @宿东)

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R&D, production, and debugging

Detector platforms and scientific instruments and equipment

Lunar Probe System

Constant measurement and control of detectors

and timely process data information

Measurement and control system and ground application system

A total of five major systems take turns to relay

( Please watch in horizontal mode , the distribution of Chang'e 5's measurement and control system, drawn by @陈志浩&王申雯/Planetary Research Institute)

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Behind this system engineering

We need more

Relay from generation to generation

Looking back to 2004

When the Chang'e Project was launched

64-year-old commander-in-chief Luan Enjie

69-year-old chief scientist Ouyang Ziyuan

75-year-old chief designer Sun Jiadong

Carried together

Chang'e-1's mission

(On November 5, 2007, after Chang'e-1 successfully orbited the moon, Ouyang Ziyuan and Sun Jiadong hugged and cried. The two white-haired old men next to them were Luan Enjie and Long Lehao, then deputy chief designer of the lunar exploration project. Source: documentary "Our Journey")

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And that year

Zhang 熇[hè] graduated 10 years ago

Just started the initial research of Chang'e 3

A Guizhou girl named Zhou Chengyu

Under 10 years old

later

Chang'e 4 successfully landed on the far side of the moon

Zhang Yan, the mission execution director

I couldn't help but burst into tears

She was 49 years old this year

(On January 3, 2019, after Chang'e-4 successfully landed on the moon, 74-year-old Academician Ye Peijian, chief designer and commander of the Chang'e-1 satellite [first from left], and Zhang Hui, executive director of the Chang'e-4 probe project [second from left], two generations of "Chang'e people", held hands tightly together. Photographer: @Xinhua News Agency reporter Jin Liwang)

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Later

Chang'e 5 successfully launched

As the first female commander of the Wenchang Launch Center

Guizhou girl Zhou Chengyu

But I'm only 24 years old

(In November 2020, Zhou Chengyu participated in the Chang'e 5 launch mission. Although she is young, she is affectionately called "Big Sister" by her colleagues. Photographer @都鑫鑫)

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When Chang'e 5 returns

There is an old man waiting in the cold night

That is Luan Enjie, who is already 80 years old.

He personally sent Chang'e on her journey

After 13 years

He personally took Chang'e "home"

(In December 2020, Luan Enjie, 80-year-old academician of the Chinese Academy of Engineering and commander-in-chief of the lunar exploration project, insisted on going to Siziwang Banner, Inner Mongolia to pick up Chang'e 5 and bring it home. Photographer @万珂)

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today

When we look up at the moon

Maybe you can't see

The debris of Chang'e-1 crashing into the moon

Yutu-1's last footprints

Can't see

Yutu-2 is still working

(On November 8, 2022, people watched the total lunar eclipse in Lingang, Shanghai. The picture shows the first phase of the total lunar eclipse. Photographer @李俊杰)

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But we know

It is this great relay

Let us look up at the moon for a thousand years

Since then, there has been Guanghan Palace

Since then, there has been Chang'e Stone

It also makes us ask questions for thousands of years

From now on, there is an answer

(The "Chang'e Stone" mentioned above refers to the official announcement on the eve of the Mid-Autumn Festival in 2022 that Chinese scientists discovered a new mineral on the moon for the first time and named it "Chang'e Stone". The picture below shows the Wanchun Pavilion in Beijing and the lunar eclipse. The photographer is @张乔, and the annotation is @王申雯/Planetary Research Institute)

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And the future

This relay will continue

Our Chang'e 6, 7, 8...

I will take up this mission and go out again

Until manned lunar landing

Until the lunar research station is built

Until the moon truly becomes

Human deep space exploration and even interstellar travel

First stop

final

We will arrive little by little

Reaching the Moon

Arrival on Mars

Arrival at an asteroid

Arrival at Jupiter

Reaching the edge of the solar system

Until we reach deeper and farther

Infinitely deep, infinitely far

universe

(Chang'e Project timeline, drawn by Liu Zhipeng/Planetary Research Institute)

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This article was created by

- Planet Research Institute -

Planning: Mr. Zhen

Written by: Sketch

Editor: Wang Huber

Design: Wang Shenwen & Liu Zhipeng

Image: Grateful Heart Map: Chen Zhihao

Model: Li Yan Reviewer: Li Fengli & Zheng Yi

-National Space Administration News and Publicity Center-

Planning: Wan Ke and Wang Shuying

Editor: Li Nan and Liu Yan

Information: Zhang Wei, Wu Shan, Zhang Gaoxiang

Expert review

Wang Qiong, Research Fellow at the Lunar Exploration and Space Engineering Center of the National Space Administration

Shi Meng, Engineer at the Lunar Exploration and Space Engineering Center of the National Space Administration

[ Acknowledgment ] The pictures in this article were strongly supported by the "National Space Administration Lunar Exploration and Space Engineering Center" and "Our Space", and we would like to express our special gratitude.

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