Scientists from IIT-Kharagpur and Archaeological Survey of India (ASI) have uncovered evidence that the Indus Valley Civilization is at least 8,000 years old, and not 5,500 years old, taking root well before the Egyptian (7000BC to 3000BC) and Mesopotamian (6500BC to 3100BC) civilizations.
What’s more, the researchers have found evidence of a pre-Harappan civilization that existed for at least 1,000 years before this. The discovery, published in the prestigious ‘Nature’ journal on May 25, may force a global rethink on the timelines of the so-called ‘cradles of civilization’.
The scientists believe they also know why the civilization ended about 3,000 years ago — climate change. “We have recovered perhaps the oldest pottery from the civilization.
We used a technique called ‘optically stimulated luminescence’ to date pottery shards of the Early Mature Harappan time to nearly 6,000 years ago and the cultural levels of pre-Harappan Hakra phase as far back as 8,000 years,” said Anindya Sarkar, head of the department of geology and geophysics at IIT-Kgp.
The team had actually set out to prove that the civilization proliferated to other Indian sites like Bhirrana and Rakhigarrhi in Haryana, apart from the known locations of Harappa and Mohenjo Daro in Pakistan and Lothal, Dholavira and Kalibangan in India.
They took their dig to an unexplored site, Bhirrana — and ended up unearthing something much bigger. The excavation also yielded large quantities of animal remains like bones, teeth, horn cores of cow, goat, deer and antelope, which were put through Carbon 14 analysis to decipher antiquity and the climatic conditions in which the civilization flourished, said Arati Deshpande Mukherjee of Deccan College, which helped analyse the finds along with Physical Research Laboratory.
The event was given a miss as the relations between the two countries are strained at present, they added. Incidents of cross-border terrorism are continuing as usual on the Western front and hence, the exchange of sweets did not take place at any location along the India-Pakistan international border from Jammu to Gujarat, the officials said.
The researchers believe that the Indus Valley Civilization spread over a vast expanse of India — stretching to the banks of the now “lost” Saraswati river or the Ghaggar-Hakra river - but this has not been studied enough because what we know so far is based on British excavations.
“At the excavation sites, we saw preservation of all cultural levels right from the pre-Indus Valley Civilization phase (9000-8000 BC) through what we have categorised as Early Harappan (8000-7000BC) to the Mature Harappan times,” said Sarkar.
While the earlier phases were represented by pastoral and early village farming communities, the mature Harappan settlements were highly urbanised with organised cities, and a much developed material and craft culture.
They also had regular trade with Arabia and Mesopotamia. The Late Harappan phase witnessed large-scale de-urbanisation, drop in population, abandonment of established settlements, lack of basic amenities, violence and even the disappearance of the Harappan script, the researchers say.
“We analysed the oxygen isotope composition in the bone and tooth phosphates of these remains to unravel the climate pattern. The oxygen isotope in mammal bones and teeth preserve the signature of ancient meteoric water and in turn the intensity of monsoon rainfall.
Our study shows that the pre-Harappan humans started inhabiting this area along the Ghaggar-Hakra rivers in a climate that was favourable for human settlement and agriculture.
The monsoon was much stronger between 9000 years and 7000 years from now and probably fed these rivers making them mightier with vast floodplains,” explained Deshpande Mukherjee.
Indus Valley evolved even as monsoon declined - They took their dig to an unexplored site, Bhirrana — and ended up unearthing something much bigger.
The excavation also yielded large quantities of animal remains like bones, teeth, horn cores of cow, goat, deer and antelope, which were put through Carbon 14 analysis to decipher antiquity and the climatic conditions in which the civilization flourished, said Arati Deshpande Mukherjee of Deccan College, which helped analyse the finds along with Physical Research Laboratory, Ahmedabad.
The researchers believe that the Indus Valley Civilization spread over a vast expanse of India — stretching to the banks of the now “lost” Saraswati river or the Ghaggar-Hakra river — but this has not been studied enough because what we know so far is based on British excavations.
“At the excavation sites, we saw preservation of all cultural levels right from the pre-Indus Valley Civilisation phase (9,000-8,000 years ago) through what we have categorised as Early Harappan (8,000-7,000 years ago) to the Mature Harappan times,” said Sarkar. At 8000 years, Indus Valley civilization is now officially the world''s oldest civilization! That now proves to the world that we Indians are actually the pioneers of civilization in human history!!
The late Harappan phase witnessed large-scale de-urbanisation, drop in population, abandonment of established settlements, violence and even the disappearance of the Harappan script, the researchers say. The study revealed that monsoon started weakening 7,000 years ago but, surprisingly, the civilization did not disappear.
The Indus Valley people were very resolute and flexible and continued to evolve even in the face of declining monsoon. The people shifted their crop patterns from large-grained cereals like wheat and barley during the early part of intensified monsoon to drought-resistant species like rice in the latter part.
As the yield diminished, the organised large storage system of the Mature Harappan period gave way to more individual household-based crop processing and storage systems that acted as a catalyst for the de-urbanisation of the civilization rather than an abrupt collapse, they say.
https://timesofindia.indiatimes.com/india/Indus-era-8000-years-old-not-5500-ended-because-of-weaker-monsoon/articleshow/52485332.cms
This is a claim I sometimes hear, and I question on what basis it is made. For I can think of another civilization, just as old if not older than China, which is BETTER preserved, especially after Mao's cultural revolution.
That is India. India is still an incredibly traditional place, where old age customs permeate everyday life. The Indus valley civilization is probably as old as Mesopotamia, and older than the Huang He.
Sanskrit and Pali derived languages are still spoken, as well as Tamil, one of the world's oldest languages. Tamil has certainly changed a lot less in 2000 years than Mandarin Chinese. India also has a lot more preserved historical monuments (the Sanchi Stupa dates from 300 BC, China's oldest temple is only from 500 AD).
One could also make the same argument for Greece, Egypt, Rome or even the Hebrews.etc. I don't think China is all that unique, although it's still a fascinating culture.
Greece I don't think is as old as China neither is Rome. Greece and Rome both date back to around the 8th century BC. Ancient Israel dates back to around 13th century BC though the Canaanites came a few centuries earlier.
Perhaps this can explain the early Jewish fixation with herding sheep as opposed to working land. Sheepherding is a vocation that involves transportable beings, not fixed and stationary land. Thus, the shepherd retains a sense of transience and impermanence that farmers do not, due to their commitment to the land they nurture. The farmer’s fate is linked to a permanent patch of earth; that’s where his energy and destiny is invested. Sheepherding for our forefathers and mothers, then, was not just a matter of practice but of principle, motivated by the fear of becoming tied to, and emotionally involved, with a land not their own. Determined not to lose sight of the essential Jewish dream of a homeland, Jews throughout the ages have similarly always maintained a transitory sense of non-arrival—unfortunately, all too often, with the unsolicited help of hostile host nations—ever-conscious of the fact that they were still on a journey. In our day and age this message is especially relevant, as we live in an unprecedented era of liberty and wealth, conditions which naturally lead to complacency and a sense of arrival. https://www.chabad.org/library/article_cdo/aid/1762017/jewish/People-of-the-Land.htm
The Shang predate all of those as they were founded sometime between 1800-1600BC Furthermore Rome is not a contiuous civilization. The same can be said for the Indus valley civilization since there is nothing really left of their civilization except ruins. We don't even know how to translate their language.
As to preserved historical monuments I think you are ignoring the 800 pound gorilla in the room which would be the Great Wall which started as walls built during the 7th century BC and was united as a project under Emperor Huangdi around 206BC.
The only real competition for China in terms of oldest civilization would probably be Egypt though it is questionable how much of Ancient Egypt's civilization and culture was intact following the Roman and Islamic conquests. The answer is almost none.
Imperial China began with the Qin dynasty around 200 BC and ended at the beginning of the 20th century. Thats well over 2000 years of one solid, identifiable culture who's outlook, technology and ideals hardly changed.
India did not maintain a cohesive empire for anywhere near as long, nor did any other place in the world. India's history is full of conflict, religious upheavals, regime changes, invasions and CHANGE. Going by the OP's rules we can call the United States an ancient empire too because people have been living here for around 11,000 years.
As I said the only culture that can really compete is ancient Egypt since Dynastic Egypt was a relatively stable identifiable culture with little change from about 3150BC to 332BC, but that is no longer continuous in any real way into the modern age where China is still hugely shaped by ideas from its imperial past.
Little except artifacts is left of the Shang, and almost nothing of the Han, in terms of buildings, while there are countless Roman remains. Even the Song has little in the ground to show for it.
Heard of the Warring states period? The Chinese Empire was unified in the Qing, younger than Rome. One could argue Rome continues today in European civilisation and the Catholic church.
First China was unified under the Qin not the Qing. They are two different dynasties in very different periods. Second, the warring states period was before the Qin and therefore before the Han and way before the Song historically it came after the Spring and Autumn period which was the end of the Zhou.
So you cannot really blame the warring states period for destroying Han buildings. As to the Song China is dotted with Song Era equipment that is still used in rural villages. Particularly water powered machinery In fact there is a whole lot left from the Han and Qin.
Furthermore the ancient cities like Luoyang, and Xi'an still exist so you cannot really say what they built is gone. There is also a bunch left from the Han culturally most notably the fact that the Chinese tend to call themselves Han Chinese which is a combination of those 2 dynasties Han for Han and Qin for China.
There is also Cofucianism which is a pretty lasting legacy of the Han Dynasty which institutionalized it. Building wise there is of course the Great Wall, and the Tomb of Shi Huangdi. All of which are marvels and then of course there is the Grand canal which is probably one of the biggest engineering feats the world has ever seen.
As to the Catholic church that is a bit of a stretch for a Roman legacy especially since they spent more time trying to surpress it then anything else. Christianity sort of showed up as a force at the end when Rome was going into severe decline.
In fact Christianity only gain large scale acceptance as the state religion less then 3 decades before Rome fell to the Alaric. Furthermore other then the city itself there are no more Romans left in the world where as there are lots of Han Chinese.
It's a really hard question to answer and largely relies upon what we are going to define as civilization. What many sources credit is that China has the longest lasting continuous civilization per the western definition of civilization.
Heck, we have Chinese writing and histories that go back 3,500 years and at that point China was already an "old" civilization.
I think the overall estimate is that China can trace a path of continuous existence back some 7,000+ years. There are equally ancient civilizations out there, but I don't think any of them have the same continuous cultural lineage that China does.
If we want to limit it to cultural "civilization" then groups like the Inuit, Australian Aborigines and several African groups easily have cultural traditions very much alive today that stretch back over tens of thousands of years. Of course, none of these meet the urban-centric definition of civilization.
Civilization is overrated, anyway. It is certainly not the paragon of a culture. Not that civilization does not have its benefits. Most scholars date the arrival of humans in Australia at 40,000 to 50,000 years ago, with a possible range of up to 125,000 years ago.
http://www.city-data.com/forum/history/1744407-china-not-worlds-oldest-continuous-civilization.html#ixzz6NTUYqknL
India is the world's largest, oldest, continuous civilization. India never invaded any country in her last 10,000 years of history. India is the world's largest democracy.
Varanasi, also known as Benares, was called "the ancient city" when Lord Buddha visited it in 500 B.C.E, and is the oldest, continuously inhabited city in the world today.
India invented the Number System. Zero was invented by Aryabhatta. The World's first university was established in Takshashila in 700BC. More than 10,500 students from all over the world studied more than 60 subjects.
The University of Nalanda built in the 4th century BC was one of the greatest achievements of ancient India in the field of education. Sanskrit is the mother of all the European languages.
Sanskrit is the most suitable language for computer software - a report in Forbes magazine, July 1987. Ayurveda is the earliest school of medicine known to humans. Charaka, the father of medicine consolidated Ayurveda 2500 years ago. Today Ayurveda is fast regaining its rightful place in our civilization.
Although modern images of India often show poverty and lack of development, India was the richest country on earth until the time of British invasion in the early 17th Century. Christopher Columbus was attracted by India's wealth.
The art of Navigation was born in the river Sindhu 6000 years ago. The very word Navigation is derived from the Sanskrit word NAVGATIH. The word navy is also derived from Sanskrit 'Nou'.
Bhaskaracharya calculated the time taken by the earth to orbit the sun hundreds of years before the astronomer Smart. Time taken by earth to orbit the sun: (5th century) 365.258756484 days.
The value of pi was first calculated by Budhayana, and he explained the concept of what is known as the Pythagorean Theorem. He discovered this in the 6th century long before the European mathematicians.
Algebra, trigonometry and calculus came from India. Quadratic equations were by Sridharacharya in the 11th century. The largest numbers the Greeks and the Romans used were 106 whereas Hindus used numbers as big as 10**53(10 to the power of 53) with specific names as early as 5000 BCE during the Vedic period. Even today, the largest used number is Tera 10**12(10 to the power of 12).
IEEE has proved what has been a century old suspicion in the world scientific community that the pioneer of wireless communication was Prof. Jagdish Bose and not Marconi. The earliest reservoir and dam for irrigation was built in Saurashtra.
According to Saka King Rudradaman I of 150 CE a beautiful lake called Sudarshana was constructed on the hills of Raivataka during Chandragupta Maurya's time. Chess (Shataranja or AshtaPada) was invented in India.
Sushruta is the father of surgery. 2600 years ago he and health scientists of his time conducted complicated surgeries like cesareans, cataract, artificial limbs, fractures, urinary stones and even plastic surgery and brain surgery.
Usage of anesthesia was well known in ancient India. Over 125 surgical equipment were used. Deep knowledge of anatomy, physiology, etiology, embryology, digestion, metabolism, genetics and immunity is also found in many texts.
When many cultures were only nomadic forest dwellers over 5000 years ago, Indians established Harappan culture in Sindhu Valley (Indus Valley Civilization). The four religions born in India, Hinduism, Buddhism, Jainism, and Sikhism, are followed by 25% of the world's population.
The place value system, the decimal system was developed in India in 100 BC. India is one of the few countries in the World, which gained independence without violence. India has the second largest pool of Scientists and Engineers in the World.
India is the largest English speaking nation in the world. India is the only country other than US and Japan, to have built a super computer indigenously. Yoga is a mental, physical and spiritual practice which has its origins in India and has existed for over 5,000 years.
The International Day of Yoga is celebrated annually on June 21st. This date was suggested by the Indian Prime Minister Narendra Modi in his UN Address as it is the longest day of the year in the Northern Hemisphere and shares special significance.
The game of Snakes & Ladders originally called 'Mokshapat' was created by the 13th century poet saint Gyandev. The ladders in the game represented virtues and the snakes indicated vices and was originally played with cowrie shells and dices.
The highest cricket ground in the world is in Chail, Himachal Pradesh. It was built in 1893 and is 2444 meters above sea level. India has the highest number of Post Offices in the world.
As of 31 March 2015 , the Indian Postal Service had154,939 post offices, of which 139,222 (89.86%) were in rural areas and 15,826 (10.14%) in urban areas.
The largest employer in India is the Indian Railways. It is the world's seventh largest commercial or utility employer, by number of employees, with over 1.376 million employees as of last published figures in 2013.
Islam is India's and the world's second largest religion after Indonesia. The first Muslims in India are thought to have been traders who came to Kerala during the lifetime of the Prophet Muhammad.
The oldest synagogue in India is in Cochin. It was built in 1568. Jews and Christians have lived continuously in India since 200 B.C. and 52 A.D. respectively.
India provides safety for refugees through large parts of its history. Zoroastrians came to the Gujarat coast to escape persecution in Persia after the conquest of the Sassanid Empire in the 16th/17th century.
More recently India has accepted refugees from Tibet, Bhutan, Afghanistan, Sri Lanka, Pakistan and Bangladesh. His Holiness, the Dalai Lama, the exiled spiritual leader of Tibetan Buddhists, runs his government in exile from Dharmashala in northern India.
According to the 1961 census, there were 1,652 languages in India. Some of these may have effectively been dialects and a few languages may have died out since then.
Six languages - Hindi, Bengali, Telugu, Marathi, Tamil and Urdu are each spoken by more than 50 million people. A total of 122 languages are each spoken by more than 10,000 people.
Albert Einstein said: We owe a lot to the Indians, who taught us how to count, without which no worthwhile scientific discovery could have been made.
Mark Twain said: India is, the cradle of the human race, the birthplace of human speech, the mother of history, the grandmother of legend, and the great grand mother of tradition. Our most valuable and most instructive materials in the history of man are treasured up in India only.
French scholar Romain Rolland said: If there is one place on the face of earth where all the dreams of living men have found a home from the very earliest days when man began the dream of existence, it is India.
Hu Shih, former Ambassador of China to USA said: India conquered and dominated China culturally for 20 centuries without ever having to send a single soldier across her border.
https://www.nriol.com/info/amazingindia.asp
An old missionary student of China once remarked that Chinese history is “remote, monotonous, obscure, and-worst of all-there is too much of it.” China has the longest continuous history of any country in the world—3,500 years of written history.
And even 3,500 years ago China’s civilization was old! This in itself is discouraging to the student, particularly if we think of history as a baffling catalogue of who begat somebody, who succeeded somebody, who slew somebody, with only an occasional concubine thrown in for human interest.
But taken in another way, Chinese history can be made to throw sharp lights and revealing shadows on the story of all mankind—from its most primitive beginnings, some of which were in Asia, to its highest point of development in philosophy and religion, literature and art.
In art and philosophy, many people think, no culture has ever surpassed that of China in its great creative periods. In material culture, though we think of the roots of our own civilization as being almost entirely European, we have also received much from Asia—paper, gunpowder, the compass, silk, tea, and porcelain.
There is nothing like a brief look at Chinese history to give one a new and wholesome respect for the Chinese people. We are likely- today to think of the Chinese as a “backward” people who are less civilized than we are, and it is true that in what we carelessly speak of as civilization—mechanization and the fruits of scientific discovery—they have, in the last hundred years, lagged behind the procession and are only beginning to catch up.
There are reasons for this temporary backwardness which we will take up later. It is wholesome to realize, however, that this attitude of superiority on the part of Western nations has existed for only about a hundred years.
Until the Opium War of 1840–42 the European merchants and voyagers who reached the distant land of China had looked upon the Chinese with a good deal of awe as a people of superior culture.
They still had much the same attitude as Marco Polo, who, in the thirteenth century, had told the people of Italy that China under the rule of the Mongols had a much more centralized and efficient system of government than European countries had.
Coming from the banking and trading city of Venice, he admired the wide use of paper money in China. To a Europe which had not yet begun to use coal he also described how the Chinese mined and burned a kind of stone which was much superior to wood as fuel.
China in fact had a civilization similar to that of Europe before the Industrial Revolution, and superior to it in many ways. The agriculture of China was more advanced and productive than that of Europe because of the great use of irrigation: and the wide network of canals that supplied water for irrigation also provided cheap transport.
The Chinese bad reached a high level of technique and art in the malting of such things as porcelain and silk, and in general the guild craftsmen of their cities were at least equal to those of the cities of pre-industrial Europe.
Moreover the Chinese had gone a good deal further than Europeans in the use of writing as a vehicle of civilization and -government, and everything which that means.
They had extensive statistics of government and finance at a time when Europe had practically none. They used written orders and regulations when Europe was still dependent on government by word of mouth.
The historical chart shows what was happening in China at the time of well-known events in the Western world. Note that some of the highest points in Chinese civilization came during the darkest days in Europe.
The central column of the chart shows a succession of Chinese dynasties. A dynasty is the reign of one ruling family, and some families remained in power for several hundred years before they were overthrown either by another Chinese family or by barbarians from the north.
The Chinese people did not come to China from somewhere else as did our own early settlers but are thought to be the direct descendants of the prehistoric cave men who lived in North China hundreds of thousands of years ago.
Chinese civilization as we know it first developed along the great bend of the Yellow River, where the earth was soft and easily worked by the crude tools of China’s Stone Age men who lived before 3000 B.C.
From the Yellow River the Chinese spread north, east, and south, sometimes absorbing aboriginal tribes, until by the time of Confucius (500 B.C.) they occupied most of the country between the Yangtze River and the Great Wall, and had developed from primitive Stone Age men to men who could domesticate animals, irrigate land, make beautiful bronze weapons and utensils, build walled cities, and produce great philosophers like Confucius.
At the time of Confucius, China consisted of many small states ruled by feudal lords. While they were loosely federated under an emperor it was not until 221 B.C., when the last of China’s feudal kingdoms fell, that China was united as a single empire. The imperial form of government lasted from 221 B.C. to 1911 A.D.
China’s first emperor, Shih Huang Ti, is known as the builder of the Great Wall, which runs from the sea westward into the deserts of Central Asia—a distance about as great as from New York City to the Rockies.
The purpose of this stupendous job of engineering was to protect the settled Chinese people from the raids of barbarian nomads who lived beyond it. Much of this great walled frontier is still standing today.
Sketch of the Great Wall of ChinaThrough the 2,000 years of China’s empire, students can trace a sort of pattern of the rise and fall of dynasties. A dynasty would come into power after a period of war and famine had reduced the population to the point where there was enough land and food to go around.
There would be prosperity, a civilized, sophisticated, and lavish court, families of great wealth and culture scattered over the country, and a flowering of art, literature, and philosophy.
Then gradually the population would increase and the farms be divided, the landlords would refuse to pay taxes, thus weakening the government, and at the same time would collect more and more rent from the peasants.
There would be savage peasant rebellions. Out of these rebellions would arise warriors and adventurers who enlisted the outlawed peasants, seized power by the sword, and overthrew the dynasty.
Once in power, the successful war lord would need to bring into his service scholars who understood administration and the keeping of records. These scholars were largely from the landlord class, the only class with leisure to acquire an education.
While they built a government service for the new dynasty they founded landed estates for themselves and their heirs. As the power of the landlords grew the state of the peasants worsened and the same things would happen all over again.
Several times dynasties were founded by nomad warriors from beyond the Great Wall. The last dynasty of the empire was founded by Manchus from Manchuria, who ruled in China from 1644 until the empire fell in 1911.
It is said that China has always absorbed her conquerors. Until the Japanese invasion her conquerors have been barbarians who looked up to the higher civilization of China and eagerly adopted it. The armored cars and tanks of a more mechanized civilization are not so readily digested.
Of What Use Today Is an Old Civilization? One may ask, “What good does it do the Chinese to have such an old civilization?” There is a very real advantage, which visitors to China often sense when they cannot explain it.
The values of culture and of being civilized have existed in China so long that they have soaked right through the whole people. Even a poor Chinese with no education is likely to have the instincts and bearing of an educated man.
He sets great store by such things as personal dignity, self-respect, and respect for others. Even if he knows the history of his country and his native region only by legend and folklore instead of reading, still he knows it—usually a surprising amount of it.
https://www.historians.org/about-aha-and-membership/aha-history-and-archives/gi-roundtable-series/pamphlets/em-42-our-chinese-ally-(1944)/the-oldest-living-civilization
When I was a kid, playing with my fellow nerdlings, we used to try to come up with the most specific address we could for ourselves—including the whole Universe.
It would go something like this: “Phil Plait, 123 Main St., Springfield, Virginia, United States of America, Earth, Solar System, Orion Spiral Arm, Milky Way Galaxy, Local Group, Virgo Supercluster, Universe.”
It looks like we can now add another locality, squeezed in between the last two: Laniakea (la-NEE-uh-KAY-uh I think is pretty close to how you pronounce it), a galactic supercluster.
The folks involved put together a video explaining it, which may help before I launch into my own discussion of it.
So, let me back up a sec. The address locations I mention above are obvious enough up to the solar system.
The Sun is located in what’s called the Orion arm in our spiral-armed Milky Way galaxy, which itself is part of a collection of a few dozen galaxies called the Local Group (we’re the biggest, along with the Andromeda galaxy).
This ragtag group is on the outskirts of much bigger cluster of galaxies, called the Virgo Cluster, which has more than 1,000 galaxies in it and is several million light years across.
That in turn is part of an even more ridiculously huge structure called the Virgo Supercluster, which contains several clusters (including, perhaps confusingly, the Virgo Cluster; these get their names from their locations in the sky).
Superclusters are among the largest scale structure in the Universe, spanning over a hundred million light years.
Mapping our local supercluster is rather difficult. First, it doesn’t really have a defined edge like a solid planet; it just kinda fades out with distance, until the next supercluster comes along.
Also, you need to get the three dimensional location of the galaxies around us, which also presents difficulties.
However, work done by a team led by astronomer Brent Tully has done just that. The team used radio telescopes to observe thousands of galaxies in the local Universe. As the Universe itself expands, it carries these galaxies away from us, and their radio waves (as well as all light they emit) loses energy—this is very similar to the more familiar Doppler shift.
Astronomers call this loss of energy “redshift,” and the farther away a galaxy is, the higher the redshift is.
But if galaxies are clumped together closely in space they’ll orbit each other, or at least their mutual gravity will affect their motion. This in turn affects the redshift for each galaxy on top of the cosmic expansion.
We know pretty well how the Universe is expanding on local scales, so if you subtract that part away, what’s left is the local motion of the galaxies.
That can be used to map how gravity of other nearby galaxies is affecting them. This let them make a map of the density and movement of galaxies in space.
That, finally, means they could map where all these galaxies are in the Universe. They found that the Virgo Supercluster, our old home, is actually part of a bigger structure they named Laniakea, which apparently is Hawaiian for “immense heaven.” No arguments here!*
Laniakea is about 500 million light years across, a staggering size, and contains the mass of 100 quadrillion Suns—100 million billion times the mass of our star. That’s a lot of mass.
The border of Laniakea isn’t well-defined, but the astronomers decided how to get a sense of it: its gravity.
Put a galaxy near Laniakea; if it falls toward the supercluster then it’s inside the border; if it falls away toward some other supercluster than it’s outside. As definitions go it’s not so bad.
It’s not the be-all-end-all; as another astronomer points out in the Nature news article, it doesn’t tell you what the eventual fate of the supercluster is (which depends on its mass and size).
Like most definitions, it depends on the question you’re trying to answer. In this case, it’s more of a guideline than a definition, and I’m OK with that.
Astronomy is both ennobling and humbling. It tells us our place in the Universe, which can make you feel small … but don’t forget that we’re a part of that Universe, and the fact that we can figure this stuff out at all makes us very big indeed.
*I’ve also seen it translated as “immeasurable heaven” which means more or less the same thing colloquially, but also has an ironic ring to it, given that measuring it is exactly what we’re doing.
https://www.theburningplatform.com/2015/02/16/my-address-is-123-main-st-richmond-virginia-united-states-of-america-earth-solar-system-orion-spiral-arm-milky-way-galaxy-local-group-virgo-supercluster-universe/
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