The meteor shower is coming, do you know its history?

December 14

The annual Geminid meteor shower

At 20:44 Beijing time

Reaching the maximum value

According to the forecast of the International Meteor Organization (IMO)

Under the most ideal conditions

There can be hundreds of meteors per hour.

Enjoy

(The Geminid meteor shower on December 14, 2017, photographed at Yaha Pass, Jiagenba Township, Kangding County, Ganzi Prefecture, Sichuan Province, photographer @罗增大扬)

▼

In the approximately 4.6 billion years of Earth's history

In fact, there are stars of different sizes every day.

Falling towards the earth

They are tiny

Can decorate the night sky of the earth

(May 4, 2022, Yezhuzhang, Heyuan, Guangdong, a meteor streaked across the night sky, photographer @唐柏鸿)

▼

Huge

It could destroy life on Earth.

(Please watch in horizontal mode, dinosaur specimens on display at the Zigong Dinosaur Museum in Sichuan, photographer @张艳)

▼

But what is even more unbelievable to many people is

In the more distant past

They may also have brought water and amino acids to Earth

It is very likely that it contributed to the birth of life

Even our Earth today

It is also made up of countless stars, large and small.

Combination

It can be said

You and I are stardust

(Please watch in horizontal mode, the Geminid meteor shower in December 2020, photographed at Lugu Lake, photographer @阿五在路)

▼

To truly understand meteor showers

Uncovering the ultimate secrets of these solar system wanderers

We need to land on small celestial bodies together with human probes

But first

We need to start with a nebula

01

The Birth of the Prodigal Son

The universe started from scratch

About 4.6 billion years ago

The solar system is only

A primordial nebula of dust and gas

(On December 12, 2020, a meteor streaked across the Orion Nebula and the Horsehead Nebula, taken at Lugu Lake in Yunnan, photographer @杨晋)

▼

after

Under the influence of gravity

The nebula begins to collapse

Countless dust and gas condensed together

Gradually a huge celestial body formed in the center

The mass accounts for 99.86% of the entire galaxy

It is

sun

The rest are gathering

The eight largest

Cleared competitors on the same track

Or incorporate the competitor into your body

Or capture them as satellites

This is

Eight planets

The masses of the eight planets

And the rest of the galaxy's mass

99%

(The Sun and the eight planets, drawn by @Zheng Borong/Planetary Research Institute)

▼

The rest of the solar system

About 0.002% of mass

It's countless dust

It's fragments of different sizes

Losers in the race for planetary growth

A wanderer in the solar system

(Pluto's mass is only 1/6 of the moon's. Because it could not clear its competitors in orbit, it was kicked out of the planetary category and is called a "dwarf planet". Image source: @NASA)

▼

They are floating in the cold space

Some are scattered around Neptune's periphery

More than 30 times the average distance from the Earth to the Sun

Known as the Kuiper Belt

Others are scattered in

The End of the Solar System

In the area where the average distance between the Earth and the Sun is thousands to tens of thousands of times

Known as the Oort Cloud

The dazzling sun and eight planets

as well as

Many inconspicuous small celestial bodies

Many distant wanderers

This is our solar system.

True appearance

(Schematic diagram of the solar system structure. The names of the Kuiper Belt and Oort Cloud come from the names of their researchers. Pluto is located in the Kuiper Belt. Map by @Zheng Borong/Planetary Research Institute)

▼

but

Some special powers

But these seemingly distant wanderers

You can still meet us from time to time

Appear in our lives

Is this a

What power?

02

Stardust Road

The ancient book Huainanzi from the Han Dynasty once recorded

More than 3,000 years ago, when King Wu defeated King Zhou

A star appeared in the night sky

A broom-like star with a long tail

(Holding Comet NEOWISE in the Tengger Desert of Alxa League, Inner Mongolia, July 18, 2020, photographer @古蒂)

▼

Such stars keep appearing

So much so that in the Mawangdui Han Tomb more than 2,000 years ago

He even drew more than 20 patterns.

They are

comet

(Some comet patterns in the Mawangdui Han Tomb. The word "comet" originally meant sweep, or the tool for sweeping, broom. Photographer @鞠潇)

▼

Comets are not Earth's closest neighbors

But often comes from

The Distant Kuiper Belt and Oort Cloud

In the hundreds of millions of years since the birth of the solar system

The planet's orbit is not yet stable

Jupiter, Saturn, Uranus, Neptune

Four giant exoplanets

Under the complex gravitational force

Changing the track

(Illustration of the hypothesis of planetary migration in the early solar system. The theory is still controversial. Map by @王申雯/Planetary Research Institute)

▼

In the process

Some small celestial bodies are attracted by the gravity of the planets.

Throw it out like a slingshot

Their orbit

Therefore, it becomes an elongated oval

Most of the time in

The icy edge of the solar system

A long journey

To get close to the sun and the earth again

(Sketch of the orbit of Halley's Comet, drawn by @王申雯/Planetary Research Institute)

▼

This also causes them to appear

Every few years, hundreds of years, or even longer

It will appear briefly in the night sky

Then disappear from sight again

Shows strong periodicity

1695

British physicist Halley, who discovered this periodicity

The comet's return time was accurately predicted to be about 76 years.

The comet was named

Halley's Comet

(Photo of Halley's Comet returning in 1986, source: Visual China)

▼****

1950s

American astronomer Whipple

For the first time, the structure of a comet was accurately described

A "dirty snowball" made of ice and stone

That’s why

When they are close to the sun

Sublimated by warmth

Often emits a lot of gas and dust

Like dragging a long tail

(The general structure of a comet, usually composed of a nucleus, coma and tail. The picture shows Comet Neowise, photography by @林子轩, drawing by @王申雯/Planetary Research Institute)

▼

And when the Earth happens to enter the orbit of the dust

Many dust particles continue to emit light and heat in the Earth's atmosphere

Stars Fall Like Rain

It's for the meteor shower

(Illustration of the causes of meteor showers, drawn by @王申雯/Planetary Research Institute)

▼

When these dust particles enter the atmosphere

Often parallel and at roughly the same speed

But because of the effect of perspective distortion

In the eyes of humans

The same meteor shower seems to be emitted from the same point

The radiant point

People also

Constellation according to the location of the radiant

Naming a meteor shower

(Please watch in horizontal mode, the Geminid meteor shower on December 16, 2018, photographed in Dagze, Aba Prefecture, Sichuan. The meteors seem to be shot from the same point, photographer @蒋涛)

▼

Around August 12 every year

Fragments of Comet Swift-Tuttle

Bring us

Perseid meteor shower

(Please watch in horizontal mode, the Perseid meteor shower on August 14, 2021, photographed at Xiaochaidan Lake in Qinghai. Photographer @Qu Xiaofeng)

▼

Around November 17th every year

Fragments of Comet Tempel-Tuttle

Bring us

Leonid meteor shower

(The Leonid meteor shower on November 18, 2022, taken in Sanya, Hainan, photographer @罗璋)

▼

On the evening of November 13, 1833

It is also the Leonid meteor shower

Brought history to mankind

The biggest meteor shower possible

More than 10,000 meteors streak across the night sky every hour

(Artwork depicting the 1833 Leonid meteor shower, image source: @wikimedia commons)

▼

But from the distant cold night visiting the earth

More than just comets

1766

Some astronomers have calculated and speculated that

There should be another planet between Mars and Jupiter

But later observations confirmed

There are a lot of asteroids here.

They are made of rock and metal

The diameters range from a few meters to 1000 kilometers.

Due to the strong gravitational pull of Jupiter

Unable to condense into a larger celestial body

They can only spread out and do their own thing

The main asteroid belt

(Sketch of the main asteroid belt, drawn by @王申雯/Planetary Research Institute)

▼

also

There are about 10% of asteroids

Other regions in the solar system

Under the influence of solar pressure

Some asteroids will also approach the sun and the earth

Release dust and form meteor showers

For example, the asteroid number 3200

Its orbital perihelion is so close to the sun

So that the surface temperature will rise to 750℃

Exhibits properties similar to comets

Scattered in its tracks

Around December 14th every year

Bringing us the Geminid meteor shower

(Artistic conception of the asteroid 3200, also named Phaethon because of its proximity to the sun, the son of the sun god in Greek mythology, image source @NASA)

▼

Around January 3rd every year

Asteroid No. 196256 also brings us

Quadrantids

(Please watch in horizontal mode, the Quadrantids meteor shower in January 2019, photographed in Yan'an, Shaanxi. The nature of the asteroid is still unclear, it may be the remnant of a comet, picture source @Visual China)

▼

Quadrantids, Perseids, Geminids

Also known as the three major periodic meteor showers

There are currently named meteor showers

There are more than 1,000

(Major meteor showers in the Northern Hemisphere throughout the year, photographer @龍柏山人, map @王申雯/Planetary Research Institute)

▼

but

Those stars that burst into our night sky from distant worlds

More than just creating a starry sky feast

Their amazing energy

Enough to affect our lives

Even life and death

03

Heaven and Earth Collide

Morning of June 30, 1908

Tunguska River in Siberia, Russia

A huge fireball streaked across the sky

And an airburst

The power is equivalent to 20 million tons of TNT

Causes trees to fall or burn within a 400km radius

Is it an asteroid or a comet?

Or the extremely rare meteorite ice

It's hard to tell now

(The Tunguska region, which seems peaceful today, experienced an unprecedented explosion more than a hundred years ago. Image source: Visual China)

▼

In July 1994

Comet Shoemaker-Levy 9 hits Jupiter

This provides mankind with a once-in-a-lifetime opportunity

The first full observation of a solar system impact event

This impact on the surface of Jupiter

Leaving a series of traces

The largest of these is roughly the size of the Earth's surface.

The energy released

It is even more like a trillion tons of TNT equivalent

(The impact mark taken by the Hubble Space Telescope after the impact on July 18, 1994, image source @NASA)

▼

Ongoing scientific research in recent years

It also provides us with detailed

Records of destruction caused by various small celestial bodies hitting the Earth

In the early days of the solar system

As the planets continue to change their orbits

Countless small stars are under the influence of gravity

Flying into the inner solar system

Like a baptism

Almost reshaped the earth's landscape

And on the moon that accompanies the earth

Leaving countless impact craters

(Please watch in horizontal mode, the moon is full of impact craters. This event is called the "Late Heavy Bombardment". Photographer: @黄一骏)

▼

Fortunately

The Earth was not as vibrant as it is today.

But this won't be the last time

66 million years

An asteroid with a diameter of about 10 km

Left in today's Gulf of Mexico

The impact crater is about 180 km in diameter.

This is likely to have led to the emergence of the dominant dinosaurs at the time.

(Strictly speaking, it is a non-avian dinosaur)

One of the important reasons for being taken away by a wave

(Whether other asteroid impacts occurred during the same period is still controversial. The dinosaur population at that time was already relatively vulnerable, while the ancestors of birds survived. The picture shows the meteorite crater on the Yucatan Peninsula in Mexico. There is still controversy about the cause of the extinction of dinosaurs. Map by @Zheng Yi/Planetary Research Institute)

▼

12,900 years ago

A massive cooling that lasted more than 1,000 years swept the world

This has led to the decline or extinction of a number of large animal species.

Including the mammoths and saber-toothed tigers we are familiar with.

Some scientists believe

This could be caused by an asteroid impact.

(This event is called the Younger Dryas event. This plant, which grows in the cold zone, invaded the south in large numbers at that time. Some people also believe that this event was related to ocean currents. The following figure shows the restoration of different types of mammoths. Map by @陈志浩&汉青&王申雯/Planetary Research Institute)

▼

But the impact of things

Always two sides of the same coin

Lower temperatures and fewer large mammals

It also caused food shortages for humans

Some people were "forced" to abandon their single hunting and gathering lifestyle

Start trying to grow crops

agriculture

This marked the beginning of a new chapter in human civilization.

(Autumn scenery of Longsheng Terraces in Guangxi, photographer @王志荣)

▼

Celestial bodies visiting Earth

It has indeed brought many positive impacts

There is a theory that

In the early Earth

When countless small celestial bodies ravage the earth's surface

It also brought life to the earth

water

(The origin of water on Earth is still controversial. Autumn scenery of Sailimu Lake, photographer @蒋晨明)

▼

There are also various amino acids

Even phosphorus

They are also crucial elements for the origin of life.

(In 1969, people witnessed the landing of a meteorite in the Murchison area of ​​Australia. Non-biologically synthesized amino acids of extraterrestrial origin were found in the meteorite, proving that they were produced by non-biological factors. Image source: @Visual China)

▼

also

The earliest iron tools made by humans

Also comes from meteorite iron in meteorites

Because of its unique shape

Easier to discover and use than general iron ore

This became the starting point of human iron tools.

(The earliest ironware unearthed from the Shang Dynasty ruins in Taixi, Gaocheng - an iron-bladed bronze axe. The iron on the blade of the bronze axe is meteorite iron. Image source: Visual China)

▼

1953

Scientists also use iron meteorites

For the first time, the age of the Earth was accurately known

4.55 billion years (± 0.7 billion years)

The formation process of iron meteorites is consistent with that of the Earth's core

Their age is roughly equivalent to the age of the Earth.

The uranium isotope decays into lead

Different uranium has different half-lives.

The lead isotopes that decay into are also different

This is like the clock of time

Just measure the ratio of different lead isotopes in iron meteorites

You can know the vicissitudes of the earth

(Patterson, a professor at the California Institute of Technology who measured this data, later became a pioneer in the prevention and control of lead pollution. The picture shows the Barringer Crater. Image source: @Visual China)

▼

In the Vredefort crater in South Africa

There are also many minerals such as gold in the surrounding area.

This is also related to celestial impact

(The specific mechanism is still controversial. Topography of the Vredefort crater in South Africa. Map by @Zheng Yi/Planetary Research Institute)

▼

visible

These prodigal sons of the solar system

Impact on life and humanity on Earth

How important is it

As they entered the Earth

We also need to go out

Towards Stardust

To uncover more of their secrets

04

Towards Stardust

1986

Taking advantage of the return of Halley's Comet

A team of six probes from the United States, the Soviet Union, Japan and Europe

The "Halley Fleet" took off one after another

For the first time, humans have used a super close distance of 596 km to

Observing the true face of comets

(The nucleus of Halley's Comet photographed by the European Space Agency's Giotto, image source @ESA)

▼

2004

The American Stardust probe

Successful flyby of Comet Wilt 2

In 2006, it brought samples of comet gas and dust back to Earth.

(Stardust, image source @NASA)

▼

2019

Japan's Hayabusa 2 probe

Successfully landed on an asteroid named Ryugu

The samples will be brought back to Earth in a recovery capsule in 2020.

A variety of amino acids are found in

This is the most conclusive evidence yet of extraterrestrial amino acids

(Hayabusa 2 probe takes out samples after landing, image source @JAXA)

▼

September 27, 2022

A NASA probe weighing 600kg

Active collision with the asteroid Dimorphos

(Please watch in horizontal mode, illustration of asteroid defense mission, drawn by @王申雯/Planetary Research Institute)

▼

and changed the asteroid's orbit

Completed humanity's first asteroid redirection mission

The threat of small celestial body impacts in the future

Humans will no longer be powerless

China will also join the race

December 13, 2012

Chang'e 2 was at a minimum distance of 3.2 km.

Flyby of the asteroid Toutatis

April 24, 2022 is China Space Day

The National Space Administration announced

Asteroid defense program to be launched

2025

Tianwen-2 will head towards

Asteroid 2016 HO3 and Comet 311P

(Research shows that 2016 HO3 is a quasi-satellite of the Earth. The picture shows an artistic imagination of the asteroid. Image source: @NASA)

▼

We are getting closer

The ultimate secret of these solar system wanderers

April 2016

In the National Astronomy Olympiad for Middle School Students

At the national team trials

A question caught all the contestants off guard

(Question 4: Stars seen by Mamenchisaurus - Junior and Senior Groups)

▼

A star with an absolute magnitude of -3.5 can be barely seen by a person with normal vision living on Earth today under good observation conditions. If this star could also be barely seen by Mamenchisaurus during the dinosaur era, please use appropriate formulas and numerical values ​​to deduce what changes this star must have undergone, and explain the reasons in detail.

Mamenchisaurus was first discovered in Sichuan in 1954.

The body length can exceed 20 meters

Mamenchisaurus sinica

It is the dinosaur with the longest neck in the world

This is an open question with no standard answer.

But it reminds us

The dinosaurs, once the dominant species on Earth, also looked up at the sky.

Watching shooting stars across the sky

Until the asteroid hit

Surrender the throne

(Mamenchisaurus Hechuan exhibited in Chongqing Natural History Museum, photographer @王晓)

▼

66 million years after the extinction of the dinosaurs

Above the Orion Arm of the Milky Way

A small main sequence star next to the sun

In the tiny, tiny, dim blue dots that surround it

A kind of intelligent life called human

Still looking up at the starry sky that the dinosaurs looked up at

(On July 27, 2022, a fireball streaked across the Milky Way over the Shenzhen Observatory. Photographer @陆不喝)

▼

The difference is

From this tiny pale blue dot, mankind will

Flying to all directions of the universe

The journey is long

Not even a return trip

But you and I are stardust

(The famous photo "Pale Blue Dot" taken by Voyager 1, the light dot in the circle is the Earth, picture source @NASA)

▼

----postscript----

Although most of us

Still can't run to the starry sky

The place we came from

But our thoughts and imagination can transcend the limitations of time and space

Towards the frontier of the universe

November 24, 2022

China National Space Administration launches a

Global Collection of Important Scientific Questions for Deep Space Exploration

Whether you are a professional or just someone who likes looking up at the stars

If you have good ideas and curiosity about the universe

Give it a try

This solicitation will end on January 31, 2023

You can click on the read original text at the end of the article to view details

(We can’t wait to head towards the universe. The Geminid meteor shower on December 20, 2015 was photographed at the Xinglong Observatory of the National Astronomical Observatory in Hebei Province. Photographer: @Steed)

▼

(Make a wish towards the long meteor! Please watch in horizontal mode, an ultra-long earth-grazing meteor, taken in Ulanbutong on June 12, 2021, photographer @申然)

▼

This article was created by

Written by: Lin Xuanwen

Editor: Director

Image: Zhou Xuguang

Design: Wang Shenwen

Proofreading: Yunwukongcheng/Dou Jing

Cover Photographer: Qu Xiaofeng/Ye Renhao

Expert reviewer: haibaraemily

PS: You don't need a telescope to observe meteor showers in general. You can observe them in an open, cloudless place with little light pollution. You don't have to stare at the radiant point or a certain patch of sky.

PPS: Mamenchisaurus was first discovered at the Mamingxi Ferry in Yibin, Sichuan. Because the discoverer, the famous paleontologist Yang Zhongjian (also my fellow Shaanxi native), had a heavy accent, the staff mistakenly recorded it as Mamenxi, hence the name. Mr. Yang also wrote a poem: "Its head is small, its neck is long, its body is large, and its tail is even more terrifying. It is about 13 meters long, and its weight is incredible."

【References】You can scroll up and down to view

DeMeo, F., Carry, B. Solar System evolution from compositional mapping of the asteroid belt. Nature 505, 629–634 (2014).

Gomes, R., Levison, H., Tsiganis, K. et al. Origin of the cataclysmic Late Heavy Bombardment period of the terrestrial planets. Nature 435, 466–469 (2005).

Moore, AMT, Kennett, JP, Napier, WM et al. Evidence of Cosmic Impact at Abu Hureyra, Syria at the Younger Dryas Onset (~12.8 ka): High-temperature melting at >2200 °C. Sci Rep 10, 4185 (2020).

Morbidelli, A., Levison, H., Tsiganis, K. et al. Chaotic capture of Jupiter's Trojan asteroids in the early Solar System. Nature 435, 462–465 (2005).

PattersonC C. Age of meteorites and the earth. Geochimica et Cosmochimica Acta, 1956,10(4): 230-237.

Plane J, Feng W, Douglas KM. Phosphorus Chemistry in the Earth's Upper Atmosphere[J]. Journal of Geophysical Research: Space Physics, 2021.

Schmitz B, Farley KA, Goderis S, et al. An extraterrestrial trigger for the mid-Ordovician ice age: Dust from the breakup of the L-chondrite parent body[J]. Science Advances, 2019, 5(9): eaax4184.

Tsiganis, K., Gomes, R., Morbidelli, A. et al. Origin of the orbital architecture of the giant planets of the Solar System. Nature 435, 459–461 (2005).

Zhang, T., Xu, K. & Ding, X. China's ambitions and challenges for asteroid–comet exploration. Nat. Astron. 5, 730–731 (2021).

Eric Chaisson, Steve McMillan, Chaisson, et al. Astronomy Today: The Solar System and the Exploration of Extraterrestrial Life[M]. Machinery Industry Press, 2016.

Dai Wensai, Hu Zhongwei, Yan Lince, et al. Evolution of the Solar System. Volume 2[M]. Shanghai Science and Technology Press, 1986.

Dai Wensai. Evolution of the Solar System[M]. Shanghai Science and Technology Press, 1979.

Flammarion. Popular Astronomy[M]. Peking University Press, 2013.

Hou Kun. The origin, development and institutionalization of astrobiology since the 1950s[D]. Shanghai Jiaotong University, 2020.

Hu Zhongwei, Xiao Naiyuan. Astronomy Course - 2nd Edition[M]. Higher Education Press, 2003.

Hu Zhongwei, Zhao Haibin. Archaeological remains of the solar system - asteroids[M]. Beijing: Science Press, 2017.

Hu Zhongwei. New Edition of Solar System Evolution[M]. Shanghai Science and Technology Press, 2014.

Hu Zhongwei. Wanderers in the Starry Sky: Comets[M]. Beijing: Science Press, 2016.

Carl Sagan. Pale Blue Dot[M]. Posts and Telecommunications Press, 2014.

Liu Xiaoqin. Research on the dissemination of astronomical knowledge in Shenbao[D]. Shanghai Jiaotong University, 2019.

Liu Xuefu. Basic Astronomy[M]. Higher Education Press, 2004.

Ouyang Ziyuan. The site of an asteroid impact on the Earth 2 billion years ago: a preliminary study of the Vredeford crater in South Africa[J]. Nature Magazine, 1997(04):193-195.

Qiu Lianghui. Early Iron-bladed Bronze Axe (Weapon) in my country[J]. Journal of Beijing Iron and Steel Institute, 1980(03):2-126.

Xi Zezong. Comet images in the Mawangdui Han Tomb Silk Book[J]. Cultural Relics, 1978(02):5-9.

Xu Weibiao. Alien Visitors-Meteorites[M]. Beijing: Science Press, 2015.

Yang Chunyan. Systematic evolution of Mamenchisauridae[D]. Chengdu University of Technology, 2014.

Ye Quanzhi. Amateur astronomy in China: current situation and future[J]. Astronomical Research and Technology, 2018, 15(2):12.

Ian Ridpath. Stars and Planets[M]. China Friendship Publishing Company, 2007.

As well as the 8th issue of Astronomy Enthusiasts magazine in 2016, NASA/JAXA/ESA/IMO (International Meteor Organization) website