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Will the world of the future be filled with cyborgs, consisting half of machine implants, capable of, and with video cameras instead of eyes, as science fiction writers promise us? Will people become fuller or slimmer, will their skin or eye color change? It is difficult to look into the future, but we can try to predict where evolution will lead in a million years by looking a million years ago when the Homo sapiens species did not exist. At the dawn of mankind, the earth was inhabited by several species of people. Heidelberg man already had similarities to Homo erectus and modern man, but had a more primitive anatomy than the Neanderthal that followed him. The last 10 thousand years have been marked by the successful development of agriculture and abundant nutrition, which has led to unhealthy obesity and related diseases, to combat which humanity is developing medical science. People have become fatter and, in some countries, increased in height. If evolution made us smaller, our bodies would require less energy, which would make sense given an overpopulated planet, says Thomas Maylund, an associate professor of bioinformatics at Aarhus University in Denmark. Another problem with overcrowding is the need to adapt to multiple daily contacts with others. In the old days of gatherers and hunters, daily contact between people was kept to a minimum. Maylund suggests that evolution will develop in humans the qualities necessary for communication. For example, remembering people's names as well as their faces will be an important ability. Here scientific technologies can come to the aid of a person. “A computer implanted in the brain would improve memory,” says Thomas. “Today, the genes responsible for memory are already known. We could change the process of remembering. Yes, it looks like science fiction. But technology already makes it possible to carry out such implantations, although it is not yet known how to connect the implant to the brain so that it is functional. This is at the experimental stage. It's just a matter of technology development. Today, people use implants to repair faulty organs, such as pacemakers. Perhaps in the future implants will be used to improve human abilities. In addition to the mentioned brain implants, an artificial eye with a video camera may appear that can recognize areas of the spectrum and visual effects that are inaccessible to vision. The technology for constructing children already exists. Scientists are able to change the genes of an embryo, although it is not yet known what this might lead to. But, according to Maylund, when this technology develops enough, it will simply become unethical not to change certain genes. The child can be designed according to the wishes of the parents. “This is the same selection that we do now with dogs, in the future we will do it with people.” - Maylund said.
“Forecasting a million years into the future is an idle exercise, but predicting the nearer future can be done with a relatively small error. Using the accumulated knowledge of bioinformatics and genetics, demographic changes can be modeled,” writes Dr. Jason A. Hodgson in his article “Fundamental Problems of Ecosystems and the Environment.” Today, with an extensive bank of genetic data collected from people all over the world, geneticists have information about combinations of genes and their distribution in human populations. On this basis, bioinformatics scientists build hypotheses regarding demographic trends. Hodgson predicts that the city will become increasingly separated from the countryside. “We are observing a process of migration from rural areas to cities, therefore, genetic diversity in cities will increase, unlike in rural areas,” the scientist writes. This process will play out differently in different parts of the world, for example in the UK, where the population in rural areas is more homogeneous and has remained relatively unchanged for hundreds of years, compared to cities where there is a significant proportion of migrants. Different nations have different rates of demographic growth. Africa's population is growing at a faster rate than light-skinned populations. Therefore, according to Hodgson's predictions, the skin color of the future person will be darker. What about space? Humans appear to eventually colonize Mars. But how will this affect evolution? How will low gravity affect the structure of the body? Limb lengthening is possible. Could cold climates cause hair growth, making humans look like Neanderthals? We don't know this, but genetic diversity will certainly increase. Hodgson argues that two new mutations appear every year in the world for every 3.5 billion pairs of chromosomes in the human genome. It would be strange to expect that in a million years people will look like they do now. Lucy Jones/bbcearth.com
Will our descendants be cyborgs?
Is the past a prologue to the future? As for the Earth, the answer can be: yes and no. As in the past, the Earth continues to be a constantly changing system. The planet faces a series of warming and cooling. Ice ages will return, as will periods of extreme warming. Global tectonic processes will continue to move continents, close and open oceans. The fall of a giant asteroid or the eruption of a super-powerful volcano can again deal a cruel blow to life.
But other events will also occur, as inevitable as the formation of the first granite crust. Myriads of living beings will die out forever. Tigers, polar bears, humpback whales, pandas, and gorillas are doomed to extinction. There is a high probability that humanity is also doomed. Many details of earth's history are largely unknown, if not completely unknowable. But studying this history, as well as the laws of nature, provides insight into what may happen in the future. Let's start with a panoramic view and then gradually focus on our time.
Endgame: the next 5 billion years
The earth is almost halfway through its inevitable demise. For 4.5 billion years, the Sun shone quite steadily, gradually increasing in brightness as it burned through its colossal reserves of hydrogen. For the next five (or so) billion years, the Sun will continue to generate nuclear energy by converting hydrogen into helium. This is what almost all stars do most of the time.
Sooner or later, hydrogen supplies will run out. Smaller stars, reaching this stage, simply fade out, gradually decreasing in size and emitting less and less energy. If the Sun were such a red dwarf, the Earth would simply freeze through. If any life survived on it, it would only be in the form of especially hardy microorganisms deep under the surface, where there could still be reserves of liquid water. However, the Sun does not face such a miserable death, since it has enough mass to have a supply of nuclear fuel for another scenario. Let us remember that each star keeps two opposing forces in balance. On the one hand, gravity attracts stellar matter to the center, reducing its volume as much as possible. On the other hand, nuclear reactions, like an endless series of explosions of an internal hydrogen bomb, are directed outward and accordingly try to increase the size of the star. The current Sun is in the stage of burning hydrogen, having reached a stable
diameter of about 1,400,000 km - this size lasted 4.5 billion years and will last for about 5 billion more.
The sun is large enough that after the end of the hydrogen burnout phase, a new, powerful helium burnout phase begins. Helium, the product of the fusion of hydrogen atoms, can combine with other helium atoms to form carbon, but this stage of the Sun's evolution will have catastrophic consequences for the inner planets. Due to more active helium-based reactions, the Sun will become larger and larger, like an overheated balloon, turning into a pulsating red giant. It will swell to the orbit of Mercury and simply swallow the tiny planet. It will reach the orbit of our neighbor Venus, swallowing it at the same time. The sun will swell a hundred times its current diameter - right up to the orbit of the Earth.
The prognosis for the earthly endgame is very grim. According to some dark scenarios, the red giant Sun will simply destroy the Earth, which will evaporate in the hot solar atmosphere and cease to exist. According to other models, the Sun will eject more than a third of its current mass in the form of an unimaginable solar wind (which will endlessly torment the dead surface of the Earth). As the Sun loses some of its mass, the Earth's orbit may expand, in which case it may avoid being absorbed. But even if we are not devoured by the huge Sun, all that remains of our beautiful blue planet will turn into a barren firebrand that continues to orbit. In the depths, individual ecosystems of microorganisms may survive for another billion years, but its surface will never again be covered with lush greenery.
Desert: 2 billion years later
Slowly but surely, even in the current quiet period of hydrogen burning, the Sun is warming up more and more. At the very beginning, 4.5 billion years ago, the Sun's luminosity was 70% of what it is today. During the Great Oxygen Event, 2.4 billion years ago, the glow intensity was already 85%. In a billion years, the Sun will shine even brighter.
For some time, perhaps even many hundreds of millions of years, the Earth's feedbacks will be able to soften this impact. The more thermal energy, the more intense the evaporation, hence the increase in cloudiness, which contributes to the reflection of most of the sunlight into outer space. Increased thermal energy means faster weathering of rocks, increased absorption of carbon dioxide and reduced levels of greenhouse gases. Thus, negative feedbacks will maintain conditions for maintaining life on Earth for quite a long time.
But a turning point will inevitably come. The relatively small Mars reached this critical point billions of years ago, losing all liquid water on the surface. In a billion years, the earth's oceans will begin to evaporate at a catastrophic rate and the atmosphere will turn into an endless steam room. There will be no glaciers or snow-capped peaks left, and even the poles will turn into the tropics. For several million years, life can persist in such greenhouse conditions. But as the Sun warms up and water evaporates into the atmosphere, hydrogen will begin to evaporate into space faster and faster, causing the planet to slowly dry out. When the oceans completely evaporate (which will probably happen in 2 billion years), the Earth's surface will turn into a barren desert; life will be on the brink of destruction.
Novopangea, or Amasia: 250 million years later
Amazia
The demise of the Earth is inevitable, but it will not happen very, very soon. A look into the less distant future paints a more attractive picture of a dynamically developing and relatively safe planet for life. To imagine the world in a few hundred million years, we must look to the past for clues to the future. Global tectonic processes will continue to play an important role in changing the face of the planet. Nowadays, the continents are separated from each other. Wide oceans separate America, Eurasia, Africa, Australia and Antarctica. But these huge areas of land are in constant motion, and its speed is approximately 2-5 cm per year - 1500 km in 60 million years. We can establish fairly accurate vectors of this movement for each continent by studying the age of the basalts of the ocean floor. The basalt near mid-ocean ridges is quite young, no older than a few million years. In contrast, the age of basalt near continental margins in subduction zones can reach more than 200 million years. It is easy to take into account all these age data on the composition of the ocean floor, rewind the tape of global tectonics back in time and get an idea of the moving
geography of the earth's continents over the past 200 million years. Based on this information, it is also possible to project the movement of continental plates 100 million years into the future.
Taking into account the current trajectories of this movement across the planet, it turns out that all continents are moving towards the next collision. In a quarter of a billion years, most of the earth's land will again become one giant supercontinent, and some geologists are already predicting its name - Novopangea. However, the exact structure of the future united continent remains a subject of scientific debate. Assembling Novopangea is a tricky game. It is possible to take into account the current movements of the continents and predict their path for the next 10 or 20 million years. The Atlantic Ocean will expand by several hundred kilometers, while the Pacific Ocean will shrink by approximately the same distance. Australia will move north towards South Asia, and Antarctica will move slightly away from the South Pole towards South Asia. Africa doesn't either
stands still, slowly moving north, moving into the Mediterranean Sea.
In a few tens of millions of years, Africa will collide with southern Europe, closing the Mediterranean Sea and erecting a mountain range the size of the Himalayas at the site of the collision, in comparison with which the Alps will seem like dwarfs. Thus, the map of the world in 20 million years will seem familiar, but slightly skewed. When modeling a world map 100 million years into the future, most developers identify common geographic features, for example, agreeing that the Atlantic Ocean will overtake the Pacific Ocean in size and become the largest water basin on Earth.
However, from this point on, models of the future diverge. One theory, extroversion, is that the Atlantic Ocean will continue to open and as a result, the Americas will eventually collide with Asia, Australia and Antarctica. In the later stages of this supercontinent assembly, North America will fold eastward into the Pacific Ocean and collide with Japan, and South America will fold clockwise from the southeast, connecting with equatorial Antarctica. All these parts fit together amazingly. Novopangea will be a single continent, stretching from east to west along the equator.
The main thesis of the extraversion model is that large convection cells of the mantle located under tectonic plates will remain in their modern form. An alternative approach, called introversion, takes the opposite view, citing previous cycles of closing and opening the Atlantic Ocean. Reconstructing the position of the Atlantic over the last billion years (or a similar ocean located between the Americas in the west and Europe along with Africa in the east), experts argue that the Atlantic Ocean closed and opened three times in cycles of several hundred million years - this conclusion suggests that heat exchange processes in the mantle are variable and episodic. Judging by the analysis of rocks, as a result of the movements of Laurentia and other continents about 600 million years ago, a precursor to the Atlantic Ocean was formed, called Iapetus, or Iapetus (named after the ancient Greek titan Iapetus, the father of Atlas).
Iapetus became closed after the assembly of Pangea. When this supercontinent began to break apart 175 million years ago, the Atlantic Ocean was formed. According to proponents of introversion (perhaps we shouldn't call them introverts), the Atlantic Ocean continues to expand and will follow the same path. It will slow down, stop and retreat in about 100 million years. Then, after another 200 million years, the Americas will again join Europe and Africa. At the same time, Australia and Antarctica will merge with Southeast Asia, forming a supercontinent called Amasia. This giant continent, shaped like a horizontal L, includes the same parts as New Pangea, but in this model the Americas form its western edge.
Currently, both supercontinent models (extroversion and introversion) are not without merit and are still popular. Whatever the outcome of this debate, everyone agrees that although the Earth's geography will change significantly in 250 million years, it will still reflect the past. The temporary assembly of continents near the equator would reduce the effects of ice ages and mild sea level changes. Where continents collide, mountain ranges will rise, changes in climate and vegetation will occur, and there will be fluctuations in oxygen and carbon dioxide levels in the atmosphere. These changes will repeat throughout Earth's history.
Impact: the coming 50 million years
A recent survey on how humanity will die reflected a very low rate of asteroid impacts - something around 1 in 100,000. Statistically, this is the same as the likelihood of dying from a lightning strike or a tsunami. But there is an obvious flaw in this forecast. Typically, lightning kills about 60 people a year. In contrast, the asteroid impact may not have killed a single person in several thousand years. But one day, a modest blow could destroy everyone.
There is a good chance that we have nothing to worry about, and neither do hundreds of subsequent generations. But there is no doubt that one day there will be a major catastrophe like the one that killed the dinosaurs. In the next 50 million years, the Earth will have to endure such a blow, perhaps more than once. It's just a matter of time and circumstances. The most likely villains are near-Earth asteroids - objects with a highly elongated orbit that passes close to the Earth's nearly circular orbit. At least three hundred such potential killers are known, and in the next few decades, some of them will pass dangerously close to Earth. On February 22, 1995, an asteroid discovered at the last moment, which received the decent name 1995 CR, whistled quite close - at several Earth-Moon distances. On September 29, 2004, the asteroid Tautatis, an elongated object approximately 5.4 km in diameter, passed even closer. In 2029, the asteroid Apophis, a fragment of approximately 325-340 m in diameter, should approach even closer, entering deeply into the lunar orbit. This unpleasant proximity will inevitably change Apophis’s own orbit and, perhaps, in the future will bring it even closer to Earth.
For every currently known asteroid crossing the Earth's orbit, there are a dozen or more that have yet to be discovered. When such a flying object is eventually discovered, it may be too late to do anything. If we find ourselves targeted, we may only have a few days to avert the danger. Dispassionate statistics give us calculations of the probability of collisions. Almost every year, debris about 10 m in diameter falls to Earth. Due to the braking effect of the atmosphere, most of these shells explode and disintegrate into
small parts before contacting the surface. But objects with a diameter of 30 meters or more, encounters with which occur approximately once every thousand years, lead to significant destruction at the impact sites: in June 1908, such a body collapsed in the taiga near the Podkamennaya Tunguska River in Russia. Very dangerous, about a kilometer in diameter, rocky objects fall to Earth about once every half a million years, and asteroids five kilometers or more can fall to Earth about once every 10 million years.
The consequences of such collisions depend on the size of the asteroid and the location of the impact. A fifteen-kilometer boulder will devastate the planet wherever it lands. (For example, the asteroid that killed the dinosaurs 65 million years ago was estimated to be about 10 km in diameter.) If a 15-kilometer pebble falls into the ocean - a 70% chance, taking into account the ratio of areas of water and land - then almost all the mountains on the globe, except for the highest, will be carried away by destructive waves. Everything below 1000 m above sea level will disappear.
If an asteroid of this size hits land, the destruction will be more localized. Everything within a radius of two to three thousand kilometers will be destroyed, and devastating fires will sweep across the entire continent, which will be the unlucky target. For some time, areas remote from the impact will be able to avoid the consequences of the fall, but such an impact will throw up an immense amount of dust from the destroyed stones and soil into the air, clogging the atmosphere for years with dusty clouds that reflect sunlight. Photosynthesis will practically disappear. Vegetation will die and the food chain will be broken. Part of humanity
may survive this catastrophe, but civilization as we know it will be destroyed.
Smaller objects would be less destructive, but any asteroid over a hundred meters in diameter, whether it crashed on land or in the sea, would cause a disaster worse than any we know of. What to do? Can we ignore the threat as something distant, not so significant in a world already full of problems that require immediate solutions? Is there any way to deflect large debris?
The late Carl Sagan, perhaps the most charismatic and influential member of the scientific community over the past half century, thought a lot about asteroids. Publicly and privately, and mostly on his famous TV show Cosmos, he advocated for concerted action at the international level. He began by telling the fascinating tale of the monks of Canterbury Cathedral who, in the summer of 1178, witnessed a colossal explosion on the Moon - a very close asteroid impact less than a thousand years ago. If such an object crashed onto Earth, millions of people would die. “Earth is a tiny corner in the vast arena of space,” he said. “It’s unlikely that anyone will come to our aid.”
The simplest step that must be taken first is to pay close attention to celestial bodies dangerously approaching the Earth - you need to know the enemy by sight. We need precise telescopes equipped with digital processors to locate flying objects approaching Earth, calculate their orbits, and make calculations about their future trajectories. It doesn't cost that much, and some things are already being done. Of course, more could be done, but at least some effort is being made.
What if we discover a large object that could crash into us in a few years? Sagan, and with him a number of other scientists and military officers, believe that the most obvious way is to cause a deviation in the asteroid’s trajectory. If started in time, even a small rocket push or a few targeted nuclear explosions could significantly shift the asteroid's orbit - and thereby send the asteroid past the target, avoiding a collision. He argued that the development of such a project required an intensive and long-term space research program. In a prophetic 1993 article, Sagan wrote: “As the threat of asteroids and comets touches every inhabited planet in the galaxy, if any, intelligent beings on them will have to band together to leave their planets and move to neighboring ones. The choice is simple - fly into space or die."
Space flight or death. To survive in the distant future, we must colonize neighboring planets. First, we need to create bases on the Moon, although our luminous satellite will remain an inhospitable world for life and work for a long time. Next is Mars, where there are more substantial resources - not only large reserves of frozen groundwater, but also sunlight, minerals and a thin atmosphere. This will not be an easy or cheap undertaking, and Mars is unlikely to become a thriving colony any time soon. But if we settle there and cultivate the soil, our promising neighbor could very well become an important step in the evolution of humanity.
Two obvious obstacles may delay or even make it impossible for humans to settle on Mars. The first is money. The tens of billions of dollars it would cost to develop and implement a mission to Mars would exceed even NASA's most optimistic budget, and that's under favorable financial conditions. International cooperation would be the only way out, but so far such large international programs have not taken place.
Another problem is the survival of astronauts, since it is almost impossible to ensure a safe flight to Mars and back. Space is harsh, with its countless meteorite grains of sand-projectiles capable of piercing the thin shell of even an armored capsule, and the Sun is unpredictable - with its explosions and deadly, penetrating radiation. The Apollo astronauts, with their week-long missions to the Moon, were incredibly lucky that nothing happened during this time. But the flight to Mars will last several months; In any space flight, the principle is the same: the longer the time, the greater the risk.
Moreover, existing technologies do not allow supplying the spacecraft with a sufficient supply of fuel for the return flight. Some inventors are talking about recycling Martian water to synthesize rocket fuel and fill tanks for the return flight, but for now this is a dream, and in the very distant future. Perhaps the most logical solution so far - the one that hurts NASA's pride, but is actively supported by the press - is a one-way flight. If we had sent an expedition, providing it with provisions for many years instead of rocket fuel, reliable shelter and a greenhouse, seeds, oxygen and water, and tools for extracting vital resources on the Red Planet itself, such an expedition could take place. It would be unimaginably dangerous, but all the great pioneers were in danger - such was Magellan’s circumnavigation of the world in 1519-1521, the expedition to the West of Lewis and Clark in 1804-1806, the polar expeditions of Peary and Amundsen at the beginning of the 20th century. Humanity has not lost its gambling desire to participate in such risky enterprises. If NASA announces a volunteer registration for a one-way mission to Mars, thousands of professionals will sign up without a second thought.
In 50 million years, Earth will still be a living and habitable planet, and its blue oceans and green continents will have shifted but will remain recognizable. Much less obvious is the fate of humanity. Perhaps man will become extinct as a species. In this case, 50 million years is quite enough to erase almost all traces of our brief rule - all cities, roads, monuments will be weathered much earlier than the end date. Some alien paleontologists will have to work hard to find the smallest traces of our existence in near-surface sediments.
However, a person can survive, and even evolve, colonizing first the nearest planets, and then the nearest stars. In this case, if our descendants go out into outer space, then the Earth will be valued even higher - as a reserve, a museum, a shrine and a place of pilgrimage. Perhaps only by leaving our planet will humanity finally truly appreciate the birthplace of our species.
Remapping the Earth: The Next Million Years
In many ways, the Earth won't change that much in a million years. Of course, the continents will shift, but no more than 45-60 km from their current location. The Sun will continue to shine, rising every twenty-four hours, and the Moon will orbit the Earth in about one month. But some things will change quite fundamentally. In many parts of the world, irreversible geological processes transform the landscape. The vulnerable contours of ocean shores will change especially noticeably. Calvert County, Maryland, one of my favorite places, where Miocene rocks with their seemingly endless fossil deposits stretch for miles, will disappear from the face of the Earth as a result of rapid weathering. After all, the size of the entire county is only 8 km and decreases by almost 30 cm every year. At this rate, Calvert County will not last 50 thousand years, let alone a million.
Other states, on the contrary, will acquire valuable land plots. An active underwater volcano off the southeastern coast of the largest of the Hawaiian islands has already risen above 3000 m (although still covered with water) and is growing in size every year. In a million years, a new island will rise from the ocean waves, already named Loihi. At the same time, the extinct volcanic islands to the northwest, including Maui, Oahu and Kauai, will correspondingly shrink under the influence of wind and ocean waves.
As for waves, experts who study rocks for future changes conclude that the most active factor in changing the Earth's geography will be the advance and retreat of the ocean. The change in the rate of rift volcanism will have an effect for a very, very long time, depending on how much more or less lava solidifies on the ocean floor. Sea levels can drop significantly during periods of quiet volcanic activity, when rocks near the bottom cool and calm down: this is what scientists believe caused the sharp drop in sea levels just before the Mesozoic extinction event. The presence or absence of large inland seas like the Mediterranean, as well as the cohesion and separation of continents, are causing significant changes in the size of coastal shelves, which will also play an important role in shaping the geosphere and biosphere over the next million years.
A million years is tens of thousands of generations in the life of mankind, which is hundreds of times longer than the entire previous human history. If man survives as a species, then the Earth may also undergo changes as a result of our progressive technological activity, and in ways that are difficult to even imagine. But if humanity dies out, then the Earth will remain approximately the same as it is now. Life will continue on land and sea; the joint evolution of the geosphere and biosphere will quickly restore the pre-industrial equilibrium.
Megavolcanoes: the next 100 thousand years
A sudden, catastrophic asteroid impact pales in comparison to the sustained eruption of a megavolcano or a continuous flow of basaltic lava. Volcanism on a planetary scale accompanied almost all five mass extinctions, including the one caused by an asteroid impact. The consequences of megavolcanism should not be confused with ordinary destruction and losses during the eruptions of ordinary volcanoes. Regular eruptions are accompanied by flows of lava, familiar to the inhabitants of the Hawaiian Islands living on the slopes of Kilauea, whose homes and everything that gets in its path it destroys, but in general such eruptions are limited, predictable and easy to avoid. Somewhat more dangerous in this category are ordinary pyroclastic volcanic eruptions, when a huge amount of hot ash rushes down the mountainside at a speed of about 200 km/h, incinerating and burying everything in its path. This was the case in 1980 with the eruptions of Mount St. Helens, Washington State, and Mount Pinatubo in the Philippines in 1991; thousands of people would have died in these disasters if not for early warning and mass evacuations.
An even more formidable danger is posed by the third type of volcanic activity: the release of huge masses of fine ash and toxic gases into the upper layers of the atmosphere. The eruptions of the Icelandic volcanoes Eyjafjallajökull (April 2010) and Grímsvötn (May 2011) are relatively weak, since they were accompanied by emissions of less than 4 km^3 of ash. However, they paralyzed air traffic in Europe for several days and harmed the health of many people in nearby areas. In June 1783, the eruption of the Laki volcano - one of the largest in history - was accompanied by the release of more than 12 thousand m3 of basalt, as well as ash and gas, which was quite enough to shroud Europe in a toxic haze for a long time. At the same time, a quarter of the population of Iceland died, some of whom died from direct poisoning from acidic volcanic gases, and the majority from starvation during the winter. The consequences of the disaster reverberated over a thousand kilometers to the southeast, and tens of thousands of Europeans, mostly from the British Isles, died from the lingering effects of the eruption.
But the deadliest was the eruption of Mount Tambora in April 1815, which ejected more than 20 km3 of lava. At the same time, more than 70 thousand people died, most of them from mass starvation resulting from damage to agriculture. The Tambora eruption released huge masses of sulfur dioxide gases into the upper atmosphere, blocking the sun's rays and plunging the Northern Hemisphere into a "year without sunlight" ("volcanic winter") in 1816. These historical events still boggle the mind, and not without reason. Of course, the number of victims does not compare with the hundreds of thousands of people who died from the recent earthquakes in the Indian Ocean and Haiti. But there is an important, frightening difference between volcanic eruptions and earthquakes. The size of the most powerful earthquake possible is limited by the strength of the rock. Hard rock can withstand a certain amount of pressure before it cracks; the strength of the rock can cause a very destructive, but still local earthquake - a magnitude of nine on the Richter scale.
In contrast, volcanic eruptions are not limited in scale. In fact, geological data irrefutably testifies to eruptions hundreds of times more powerful than the volcanic disasters preserved in the historical memory of mankind. Such gigantic volcanoes could darken the sky for years and change the appearance of the earth's surface over many millions (not thousands!) of square kilometers. The giant eruption of Mount Taupo on the North Island, New Zealand, occurred 26,500 years ago; More than 830 km^3 of magmatic lava and ash were erupted.
The Toba volcano in Sumatra exploded 74,000 years ago and erupted more than 2,800 km^3 of lava. The consequences of a similar catastrophe in the modern world are difficult to imagine. Yet these supervolcanoes, which produced the greatest cataclysms in Earth's history, pale in comparison to the giant basalt flows (scientists call them "traps") that caused mass extinctions. Unlike one-time eruptions of supervolcanoes, basalt flows cover a huge time period - thousands of years of continuous volcanic activity. The most powerful of these cataclysms, usually coinciding with periods of mass extinction, spread hundreds of thousands of millions of cubic kilometers of lava. The largest catastrophe occurred in Siberia 251 million years ago during the great mass extinction and was accompanied by the spreading of basalt over an area of more than a million square kilometers. The death of the dinosaurs 65 million years ago, often attributed to a large asteroid impact, coincided with a gigantic basaltic lava spill in India, which gave rise to the largest igneous province, the Deccan Traps, with a total area of about 517,000 km2, and the volume of mountains that grew up to 500,000 km2 ^3.
These huge territories could not have formed as a result of a simple transformation of the crust and upper part of the mantle. Modern models of basalt formations reflect the idea of an ancient era of vertical tectonics, when giant bubbles of magma slowly rose from the boundaries of the hot core of the mantle, splitting the earth's crust and splashing out onto the cold surface. Such phenomena occur extremely rarely in our time. According to one theory, the time interval between basalt flows is approximately 30 million years, so it is unlikely that we will live to see the next one.
Our technological society will certainly receive timely warning of the possibility of such an event. Seismologists are able to track the flow of hot, molten magma rising to the surface. We may have hundreds of years to prepare for such a natural disaster. But if humanity falls into another surge of volcanism, there will be little we can do to counter this most severe of earthly tests.
Ice factor: next 50 thousand years
In the foreseeable future, the most significant factor determining the appearance of the earth's continents is ice. Over several hundred thousand years, ocean depth is highly dependent on the global volume of frozen water, including mountain ice caps, glaciers and continental ice sheets. The equation is simple: the greater the volume of frozen water on land, the lower the water level in the ocean. The past is the key to predicting the future, but how do we know the depth of ancient oceans? Satellite observations of ocean water levels, while incredibly accurate, are limited to the last two decades. Sea level measurements from level gauges, although less accurate and subject to local variations, have been collected over the last century and a half. Coastal geologists can map features of ancient coastlines—for example, elevated coastal terraces that can be traced back to tens of thousands of years of coastal-marine sediments—that may reflect periods of rising water levels. The relative position of fossil corals, which typically grow on sun-warmed, shallow ocean shelves, might extend our record of past events back into the centuries, but that record would be distorted as such geologic formations rise, sink, and tilt episodically.
Many experts began to pay attention to a less obvious indicator of sea level - changes in the ratios of oxygen isotopes in small shells of marine mollusks. Such relationships can tell much more than the distance between any celestial body and the Sun. Due to their ability to respond to changes in temperature, oxygen isotopes provide the key to deciphering the volume of the Earth's ice cover in the past and, accordingly, to changes in water levels in the ancient ocean. However, the relationship between the amount of ice and oxygen isotopes is tricky. The most abundant isotope of oxygen, accounting for 99.8% of the oxygen in the air we breathe, is thought to be light oxygen-16 (with eight protons and eight neutrons). One in 500 oxygen atoms is heavy oxygen-18 (eight protons and ten neutrons). This means that one out of every 500 water molecules in the ocean is heavier than normal. When the ocean is heated by the sun's rays, water containing light isotopes of oxygen-16 evaporates faster than oxygen-18, making water in low-latitude clouds lighter than in the ocean itself. As clouds rise into cooler layers of the atmosphere, the heavy oxygen-18 water condenses into raindrops faster than the lighter oxygen-16 water, and the oxygen in the cloud becomes even lighter.
As clouds inevitably move toward the poles, the oxygen in their constituent water molecules becomes much lighter than in seawater. When precipitation falls over polar glaciers and glaciers, light isotopes freeze in the ice and seawater becomes even heavier. During periods of maximum cooling of the planet, when more than 5% of the Earth's water turns into ice, sea water becomes especially saturated with heavy oxygen-18. During periods of global warming and glacier retreat, the level of oxygen-18 in seawater decreases. Thus, careful measurements of oxygen isotope ratios in coastal sediments can provide insight into changes in surface ice volume in retrospect.
This is exactly what geologist Ken Miller and his colleagues have been doing at Rutgers University for several decades, studying the thick layers of marine sediments covering the New Jersey coast. These deposits, which record the geological history of the last 100 thousand years, are rich in the shells of microscopic fossil organisms called foraminifera. Each tiny foraminifera stores oxygen isotopes in its composition in the proportion that was in the ocean at the time the organism grew. Measuring oxygen isotopes in New Jersey's coastal sediments, layer by layer, provides a simple and accurate means of estimating the volume of ice during a relevant time period.
In the recent geological past, the ice cover has waxed and waned, with corresponding large fluctuations in sea level every few thousand years. At the peak of the ice ages, more than 5% of the water on the planet turned into ice, lowering sea levels by about a hundred meters relative to today. It is believed that about 20 thousand years ago, during one of these periods of low standing water, a land isthmus formed across the Bering Strait between Asia and North America - it was along this “bridge” that people and other mammals migrated to the New World. During the same period, the English Channel did not exist, and there was a dry valley between the British Isles and France. During periods of maximum warming, when glaciers virtually disappeared and snow caps thinned on mountain tops, sea levels rose, becoming about 100 m higher than today, submerging hundreds of thousands of square kilometers of coastal areas across the planet.
Miller and his collaborators have calculated more than a hundred cycles of glacial advance and retreat over the past 9 million years, and at least a dozen of them occurred in the last million - the range of these wild fluctuations in sea level reached 180 m. Each cycle may be slightly different from the next, but the events occur with obvious periodicity and are associated with the so-called Milankovitch cycles, named after the Serbian astronomer Milutin Milankovitch, who discovered them about a century ago. He found that well-known changes in the parameters of the Earth's movement around the Sun, including the tilt of the Earth's axis, the eccentricity of the elliptical orbit and slight fluctuations in its own axis of rotation, cause periodic changes in climate with intervals of 20 thousand years to 100. These shifts affect the flow of solar energy , reaching the Earth, and thus causing significant climate fluctuations.
What awaits our planet in the next 50 thousand years? There is no doubt that sharp fluctuations in sea level will continue, and it will fall and rise more than once. Sometimes, probably over the next 20 thousand years, the snow caps on the peaks will grow, the glaciers will continue to increase, and the sea level will drop sixty meters or more - a level the sea has dropped to at least eight times in the last million years. This will have a powerful impact on the contours of continental coastlines. The East Coast of the United States will expand many kilometers eastward, according to
as the shallow continental slope becomes exposed. All major harbors on the East Coast, from Boston to Miami, will become dry inland plateaus. A new ice-covered isthmus will connect Alaska to Russia, and the British Isles could once again become part of mainland Europe. Rich fisheries along continental shelves will become part of the land.
As for sea level, if it decreases, then it must certainly rise. It is quite possible, even very likely, that within the next thousand years sea levels will rise by 30 m or more. Such a rise in sea levels, quite modest by geological standards, would redraw the map of the United States beyond recognition. Thirty meters of sea level rise will flood much of the coastal plains on the East Coast, pushing coastlines up to one hundred and fifty kilometers westward. The main coastal cities - Boston, New York, Philadelphia, Washington, Baltimore, Wilmington, Charleston, Savannah, Jacksonville, Miami and many others - will be under water. Los Angeles, San Francisco, San Diego and Seattle will disappear into the sea waves. It will flood almost all of Florida, and a shallow sea will stretch out in place of the peninsula. Most of the states of Delaware and Louisiana will be under water. In other parts of the world, the damage caused by rising sea levels will be even more devastating.
Entire countries will cease to exist - Holland, Bangladesh, the Maldives. Geological data irrefutably demonstrates that such changes will continue to occur. If warming turns out to be as rapid as many experts believe, water levels will rise quickly, by about 30 cm per decade. Normal thermal expansion of seawater during periods of global warming can increase sea level rise to an average of three meters. This will undoubtedly be a problem for humanity, but will have very little impact on the Earth. Still, this won't be the end of the world. This will be the end of our world.
Warming: the next hundred years
Most of us do not look several billion years ahead, just as we do not look several million years or even a thousand years. We have more pressing concerns: How will I pay for higher education for my child in ten years? Will I get a promotion in a year? Will the stock market go up next week? What to cook for lunch? In this context, we need not worry. Barring an unforeseen catastrophe, our planet will remain almost unchanged in a year or ten years. Any difference between what is now and what will be a year from now is almost imperceptible, even if the summer turns out to be incredibly hot, or the crops suffer from drought, or an unusually strong storm blows up.
And such changes are being observed across the globe. The shores of Chesapeake Bay report a steady increase in tide levels compared to previous decades. Year after year, the Sahara spreads further north, turning Morocco's once fertile farmland into a dusty desert. The ice of Antarctica is rapidly melting and breaking up. Average air and water temperatures are constantly rising. All this reflects a process of progressive global warming - a process that the Earth has experienced countless times in the past and will experience in the future.
Warming may be accompanied by other, sometimes paradoxical, effects. The Gulf Stream, a powerful ocean current that carries warm water from the equator to the North Atlantic, is driven by the large temperature difference between the equator and high latitudes. If global warming reduces the temperature contrast, as some climate models suggest, the Gulf Stream could weaken or stop altogether. Ironically, the immediate result of this change would be to transform the temperate climates of the British Isles and Northern Europe, which are now
heated by the Gulf Stream, in much cooler times. Similar changes will occur with other ocean currents - for example, with the current coming from the Indian Ocean into the South Atlantic past the Horn of Africa - this could cause a cooling of the mild climate of South Africa or a change in the monsoon climate that provides parts of Asia with fertile rains.
When glaciers melt, sea levels rise. According to the most conservative estimates, it will rise by half a meter to a meter in the next century, although, according to some data, in some decades the increase in sea water levels may fluctuate within a few centimeters. Such changes in sea level will affect many coastal communities around the world and pose a real headache for civil engineers and beach owners from Maine to Florida, but in principle a rise of up to one meter in densely populated coastal areas can be managed. At least the next one or two generations of residents will not have to worry about the sea encroaching on the land. However, certain species of animals and plants may suffer much more seriously.
The melting of polar ice in the north will reduce the habitat of polar bears, which is very unfavorable for preserving the population, the number of which is already declining. The rapid shift of climate zones towards the poles will negatively affect other species, especially birds, which are especially susceptible to changes in seasonal migration and feeding zones. According to some data, an average increase in global temperatures of just a couple of degrees, as most climate models suggest over the coming century, could reduce bird populations by almost 40% in Europe and by more than 70% in the fertile rainforests of north-eastern Australia. A major international report says that of the roughly 6,000 species of frogs, toads and lizards, one in three will be in danger, largely due to the spread of a fungal disease that is deadly to amphibians, fueled by a warm climate. Whatever other effects of warming may be revealed in the coming century, it appears that we are entering a period of accelerated extinction.
Some changes in the next century, whether inevitable or only probable, may be instantaneous, be it a major destructive earthquake, the eruption of a supervolcano, or the impact of an asteroid more than a kilometer in diameter. Knowing the history of the Earth, we understand that such events are common and therefore inevitable on a planetary scale. Nevertheless, we build cities on the slopes of active volcanoes and in the most geologically active zones of the Earth in the hope that we will dodge a “tectonic bullet” or a “space projectile.”
Between the very slow and rapid changes are geological processes that usually take centuries or even millennia - changes in climate, sea level and ecosystems that can remain undetected for generations. The main threat is not the changes themselves, but their degree. Because the state of the climate, the position of the sea level or the very existence of ecosystems may reach a critical level. The acceleration of positive feedback processes can hit our world unexpectedly. What would normally take a millennium to complete can
appear in a decade or two.
It's easy to be complacent if you misread the rock record. For a time, until 2010, concerns about modern events were tempered by studies looking back 56 million years ago, the time of one of the mass extinctions that dramatically affected the evolution and distribution of mammals. This terrible phenomenon, called the Late Paleocene Thermal Maximum, caused the relatively abrupt extinction of thousands of species. The study of the thermal maximum is important for our time because it is the most famous, documented sharp temperature shift in Earth's history. Volcanic activity caused a relatively rapid increase in atmospheric levels of carbon dioxide and methane, two inseparable greenhouse gases, which in turn led to a positive feedback that lasted more than a thousand years and was accompanied by moderate global warming. Some researchers see in the late Paleocene thermal maximum a clear parallel with the modern situation, of course, unfavorable - with a rise in global temperature by an average of almost 10 ° C, a rapid rise in sea level, ocean acidification and a significant shift of ecosystems towards the poles, but not so catastrophic, to threaten the survival of most animals and plants.
The shock of the recent findings by Lee Kemp, a geologist at Pennsylvania State University, and his colleagues has left us with little reason for optimism. In 2008, Kemp's team gained access to material recovered from drilling in Norway that allowed them to trace the events of the late Paleocene Thermal Maximum in detail - sedimentary rocks, layer by layer, captured the finest details of the rate of change in atmospheric carbon dioxide and climate. The bad news is that the thermal maximum, which is over a decade
considered the fastest climate shift in Earth's history, was driven by changes in the composition of the atmosphere that were ten times less intense than what is happening today. Global changes in the composition of the atmosphere and average temperature, formed over a thousand years and ultimately leading to extinction, have occurred in our time during the last hundred years, during which humanity burned enormous quantities of hydrocarbon fuels.
This is an unprecedentedly rapid change, and no one can predict how the Earth will react to it. At the Prague conference in August 2011, where three thousand geochemists gathered, there was a very sad mood among specialists, sobered by new data on the late Paleocene thermal maximum. Of course, for the general public, the forecast of these experts was formulated in rather cautious terms, but the comments that I heard on the sidelines were very pessimistic, even frightening. Greenhouse gas concentrations are increasing too quickly, and the mechanisms for absorbing this excess are unknown. Will this cause a massive release of methane with all the subsequent positive feedbacks that such a development entails? Will sea levels rise by a hundred meters, as has happened many times in the past? We are entering a zone of terra incognita, carrying out a poorly designed experiment on a global scale, the likes of which the Earth has never experienced in the past.
Judging by the rock data, no matter how resistant to shocks life may be, the biosphere is under great stress at turning points of sudden climate shifts. Biological productivity, particularly agricultural productivity, will drop to catastrophic levels for some time. In rapidly changing conditions, large animals, including humans, will pay a heavy price. The interdependence of rocks and the biosphere will continue unabated, but humanity's role in this billion-year saga remains incomprehensible.
Perhaps we have already reached a tipping point? Perhaps not in the current decade, perhaps not at all during the lifetime of our generation. But such is the nature of turning points - we recognize such a moment only when it has already arrived. The financial bubble is bursting. The population of Egypt rebels. The stock exchange is crashing. We realize what is happening only in retrospect, when it is too late to restore the status quo. And there has never been such a restoration in the history of the Earth.
Excerpt from Robert Hazen's book: "
The brevity of human life creates the illusion that nothing is changing on Earth - it seems to us that the planet has always been the way we see it now, with the same landscapes, animals and plants... But geology and paleontology provide us with indisputable evidence of the constant transformation of the Earth. After all, in fact, our planet has “shuffled” its continents dozens of times and changed the species composition of flora and fauna under the influence of new external conditions.Earth after 5 million years
Today everyone is talking about global warming, which is caused by greenhouse gases created by human activity. However, the same human activity also leads to cooling in certain parts of the planet - although in general this can be called a gross imbalance of the climate. But let's take it in order...
On April 20, 2010, an explosion occurred on the Deepwater Horizon oil production platform located in the Gulf of Mexico (and, by the way, not the first in the oil industry). Two days later, the platform sank and oil from the underwater well began flowing into the open sea. How much of it leaked out before British Petroleum engineers plugged the well is not known for certain. According to various sources, more than a trillion liters of crude oil got into the waters of the Gulf of Mexico, where the Gulf Stream is formed.
Following the “floating money,” the Americans pumped 500 million liters of Corexit and other chemicals into the water to bind oil and deposit it to the bottom. This mixture is constantly expanding in volume, spreading along the ocean floor and having a serious impact on the entire thermoregulation system of the planet by destroying the boundary layers of the warm flow of water. This may come as news to some, but according to the latest satellite data, the Gulf Stream no longer exists.
This “river” of warm water moved across the Atlantic Ocean, warming northern Europe and protecting it from the winds. Currently, the circulation system has died in a number of places and is dying in other areas. As a result of these processes, unheard-of high temperatures occurred in Moscow, droughts and floods occurred in Central Europe, temperatures increased in many Asian countries, and massive floods occurred in China, Pakistan and other Asian countries.
Climate change has already begun. All this means that it will be possible to forget about a stable climate and a quiet life: in the future there will be violent mixing of seasons, an increase in the size of droughts and floods in various places on the Earth. This will lead to frequent crop failures, an unstable economy, epidemics, changes in flora and fauna, as well as mass migration of people from areas unsuitable for human habitation. The world's population is expected to be cut in half, if not more.
But no matter what natural disasters humanity has to endure, after 5 million years the Earth will one way or another find itself in the grip of another ice age. A huge ice shell will cover the entire Northern Hemisphere up to moderate latitudes, and the Antarctic ice sheet will also expand. The harsh, dry climate will transform the landscapes of the planet: most of the land will be occupied by cold deserts and steppes, in which only the most unpretentious animals can survive.
Earth in 50-200 million years
According to the modern theory of continental drift, 200-300 million years ago, in the Mesozoic, there was a single supercontinent - Pangea. Initially, it split into two parts - northern Laurasia and southern Gondwana. From Laurasia, Eurasia and North America were subsequently formed, from Gondwana - South America, Africa, Australia, Antarctica, the Arabian Peninsula and Hindustan.
Scientists believe that Pangea was already the third or fourth supercontinent in the history of our planet. Its predecessors were Rodinia in the Proterozoic (1 billion years ago) and Nuna in the Paleoproterozoic (1.8-1.5 billion years ago). Most scientists today agree that in the distant future, the Earth will again face a merger of continents, which will completely change the appearance of the planet.
Modern continents form Amasia (from the words “America” and “Eurasia”) - a single continent in the region of the modern Arctic, surrounded by a global ocean. Most of the continent will be occupied by harsh deserts and mountain ranges. Wet coasts will be at the mercy of powerful storms. Antarctica will also move towards the equator and shed its ice shell.
Collisions of continental plates will cause increased volcanic activity, which will release large amounts of carbon dioxide into the atmosphere and significantly warm the climate. There will be almost no ice left on Earth; the oceans will swallow up vast expanses of land. A real feast of life will begin on a warm and humid planet.
Geologists from Yale University tried to understand what a new supercontinent that will unite all modern parts of the world will be like in millions of years. According to the theory of Professor David Evans, a specialist in the internal structure and history of continents, both Asia and North America could become the center of the new continent. The main thing is that this continent will be exactly on the territory of the modern Arctic Ocean. The continents will be “sewn together” by a new mountain range (the Himalayas, for example, were formed at the merger of Eurasia and the Gondwana-Hindustan section).
The calculation results were published in the journal Nature. Professor Evans sighs: “Of course, this kind of reasoning cannot be tested by simply waiting 100 million years - but we can use the trajectories of ancient supercontinents to better understand how this eternal tectonic dance of the Earth occurs.”
The question is, will there still be people living on the planet of the future? Fatalists believe that this is impossible - after all, the once dominant dinosaurs and the supposedly highly civilized Atlantean race disappeared from the face of the Earth, unable to withstand global changes and disasters. This philosophy is very convenient, isn't it? After all, it’s easier for many to know that “we’re all going to die” and nothing depends on us, so you can waste your life as you please, leaving behind only devastation and garbage. After all, these are precisely the thoughts that a person expresses when he says: after me there may be a flood.
But let's face it: a person has every chance to both correct his mistakes and adapt to the most difficult conditions of existence (yes, we are like that), and invent high technologies to protect against disasters. The main thing is not to lose hope, not to hide behind convenient excuses, to believe in US - after all, only thanks to hope and striving for the better, a person once straightened his shoulders and became who he is.
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Like all living things on Earth, you and I continue to evolve. If you don’t believe me, remember the story of wisdom teeth, which were well developed among our distant ancestors who ate rough food. In our country they were reduced as unnecessary.
We are in website wondered what a person would look like after millions of years of evolution if conditions on planet Earth roughly correspond to emerging trends and probable forecasts.
- Height. Over the past 200 years, the population of developed countries has grown by 10 cm due to improved living conditions and quality nutrition. If this continues, the height of men will reach 2 meters, but hardly higher. (Sources: Mean Body Weight, Height, and body mass index, United States 1960–2002, wikipedia)
- Leather will become darker as the races will intensively mix. And dark skin will better protect against ultraviolet radiation, which will penetrate the Earth in excess. (Source: livescience, nickolaylamm)
- Body. A person will reduce his physical costs with the help of machines and robots. Physical strength will not be in demand, the muscles will shrink. Technology will become an integral part of our body, embedded chips and gadgets will become commonplace. (Source: futurehumanevolution)
- Hands. Constant use of keyboards and touch screens will make your hands and fingers thinner and longer. (Source: the-scientist)
- Legs. The body will change to suit a sedentary lifestyle, long strong legs will not be needed. The fibula is reduced, which is typical for land animals. This bone serves to rotate the foot, which was important for our tree-climbing ancestors. But for us, sideways mobility of the ankle has become rather harmful, often leading to dislocations. (Source: futurehumanevolution, anthropogenez)
- Toes. Our ancestors also used them for climbing trees. In the line from Australopithecus to us, the fingers have noticeably shortened, obviously this is not the limit. Probably their number will also decrease. Land animals always come to a decrease in their numbers, and the horse is the record holder here. (Source: anthropogenez)
- Rib cage. If it becomes increasingly difficult to obtain oxygen from the atmosphere, the lungs will increase in size. The chest will also increase.
- Head. It is still unclear whether the person of the future will have a smaller or larger cranial volume than now. On the one hand, compared to Cro-Magnons, the human brain has become, oddly enough, smaller. It becomes more compact, which only contributes to its faster operation. On the other hand, more and more caesarean sections allow babies with large heads to survive. This will affect the increase in its average size. Therefore, there will probably not be a natural birth in the future. (Sources: anthropogenez, bbc, vox)
- Teeth. Humanity is switching to increasingly soft food. The number of teeth and their size will decrease, this will entail a reduction in the jaw and mouth. (
The earth is in a constant state of change. Whether the result of human activity or solar disturbances, the future of Earth is guaranteed to be more than interesting, but not without chaos. The following list presents the ten major events that the Earth is predicted to experience over the next billions of years.
1. New Ocean
~10 million years
One of the hottest places on Earth, the Afar Depression is located between Ethiopia and Eritrea - on average 100 meters below sea level. At this point, there is only 20 km between the surface and the boiling hot magma, and the land is slowly thinning due to tectonic movements. Comprising a killer array of volcanoes, geysers, earthquakes and toxic heated water, the depression is unlikely to become a resort; but in 10 million years, when this geological activity ceases, leaving only a dry basin, the area will eventually fill with water and a new ocean will form - an ideal place for water skiing in the summer.
2. An event with a huge impact on Earth
~100 million years
Given Earth's rich history and the relatively large amount of random debris swirling through space threatening planets, scientists predict that within the next 100 million years, Earth will be impacted by some kind of event comparable to the event that caused the Cretaceous-Paleogene extinction event 65 million years ago. This is, of course, bad news for any life on planet Earth. And while some species will undoubtedly survive, the impact will likely mark the end of the Age of Mammals—the current Cenozoic Era—and Earth will instead enter a new era of complex life. Who knows what kind of life will flourish on this newly cleansed Earth? Maybe one day we will share the universe with intelligent invertebrates or amphibians. At this point, we can only imagine what will happen.
3. Pangea Ultima
~250 million years
Over the next 50 million years, Africa, which has been migrating north for the last 40 million years, will eventually begin to collide with southern Europe. This movement will seal the Mediterranean Sea for 100 million years, and create thousands of kilometers of new mountain ranges to the delight of climbers around the world. Australia and Antarctica are also eager to be part of this new supercontinent, and will continue to move north to merge with Asia. While all this is happening, America will continue its course westward, further away from Europe and Africa, towards Asia.
What happens next is still being discussed. It is believed that while the Atlantic Ocean is rising, a subduction zone will form at the western boundary, which will stretch from the floor of the Atlantic Ocean deep into the earth. This would effectively change the direction in which America is heading, eventually bringing it to the eastern edge of the Eurasian supercontinent within about 250 million years. If this does not happen, we can expect both Americas to continue their journey westward until they merge with Asia. In any case, we can hope for the formation of a new hypercontinent: Pangea Ultima - 500 million years after the creation of the previous continent, Pangea. After this, it will likely split again and begin a new cycle of drift and merger.
4. Gamma Ray Burst
~600 million years
If an event with a huge impact on the Earth, repeating every few hundred million years, doesn't seem like the worst option, then know that the Earth constantly has to contend with rare gamma-ray bursts - streams of ultra-high energy radiation usually emitted by supernovae. Although we experience weak gamma-ray bursts every day, an explosion occurring in a nearby solar system - within 6,500 light-years of us - has enough potential to wreak havoc in its path.
With more energy than the Sun produced in its entire life cycle hitting Earth in minutes and even seconds, gamma rays would burn up much of the Earth's ozone layer, causing radical climate change and widespread environmental damage, including mass extinctions.
Some believe that this burst of gamma rays triggered the second largest mass extinction in history: the Ordovician-Silurian extinction event 450 million years ago, which wiped out 60% of all life on Earth.
Like all events in astronomy, the exact timing of the set of events that will trigger an Earth-bound gamma-ray burst is very difficult to predict, although typical estimates put the period at 0.5-2 billion years. But this time could be reduced to a million years if the threat of the Eta Carinae Nebula is realized.
5. Uninhabitable
~1.5 billion years
Because the Sun gets hotter as it grows in size, the Earth will eventually become uninhabitable due to its proximity to the hot sun. By this time, everyone, even the most stable forms of life on Earth, will die. The oceans will dry up completely, leaving only deserts of burnt earth. As time passes and temperatures rise, the Earth may follow the path of Venus and become a toxic wasteland as it heats up to the boiling point of many toxic metals. What remains of humanity will have to vacate this space in order to survive. Fortunately, by that time Mars will have entered the habitable zone and will be able to serve as a temporary shelter for the remaining people.
6. Disappearance of the magnetic field
~2.5 billion years
Some believe, based on today's understanding of the Earth's core, that within 2.5 billion years the Earth's outer core will no longer be liquid, but will begin to freeze. As the core cools, the Earth's magnetic field will slowly decay until it ceases to exist at all. In the absence of a magnetic field, there will be nothing to protect the Earth from solar winds, and the Earth's atmosphere will gradually lose its light compounds - such as ozone - and gradually turn into miserable remains of itself. Now with an atmosphere similar to Venus, the Earth will experience the full force of solar radiation, making an already inhospitable land even more treacherous.
7. Internal catastrophe of the solar system
~3.5 billion years
In about 3 billion years, there is a small but significant chance that Mercury's orbit will elongate in such a way that it will cross the path of Venus. At the moment, we cannot predict exactly what will happen or when it will happen, but in the best case scenario, Mercury will simply be absorbed by the Sun or destroyed by a collision with its older sister Venus. What about the worst case scenario? Earth could collide with any of the other non-gaseous planets, whose orbits would be radically destabilized by Mercury. If somehow the inner solar system remains intact and continues to operate uninterrupted, then within five billion years the orbit of Mars will intersect with Earth, once again creating the possibility of disaster.
8. New picture of the night sky
~4 billion years
Years will pass, and any life on Earth will be pleased to observe the steady growth of the Andromeda galaxy in the picture of our starry sky. It will be a truly magnificent sight to see a perfectly formed spiral galaxy glowing in the sky, full of majesty, but it won't last forever. Over time, it will begin to become horribly distorted and merge with the Milky Way, plunging the stable stellar arena into chaos. Although a direct collision between celestial bodies is unlikely, there is a small chance that our solar system could be scooped up and thrown into the abyss of the universe. Either way, our night sky will be, at least temporarily, decorated with trillions of new stars
9. Garbage Ring
~5 billion years
Despite the fact that the Moon is constantly receding at a distance of 4 cm per year, the Sun has entered the red giant phase and it is likely that the current trend will stop. The additional force exerted on the Moon by the huge, inflated star would be enough to crash the Moon directly onto Earth. When the Moon reaches its Roche limit, it will begin to disintegrate as the force of gravity exceeds the force holding the satellite together. After this, perhaps a ring of debris will form around the Earth, giving any life on earth a beautiful display until the debris falls to the ground after many millions of years.
If this doesn't happen, there is another way the Moon could fall back to its parent planet. If the Earth and Moon continue to exist in their current form with their unchanged orbits, then in about 50 billion years the Earth will become tidally locked with the Moon. Shortly after this event, the Moon's orbital altitude will begin to decay, while the Earth's rotation rate will rapidly increase. This process will continue until the Moon reaches the Roche limit and disintegrates, forming a ring around the Earth.
10. Destruction
Unknown
The likelihood that the Earth will collapse within the next tens of billions of years is very high. Whether in the cold grip of a treacherous planet, or from suffocation in the arms of our dying Sun, it will undoubtedly be a sad moment for all the surviving people - even if they do not remember which planet it is.
