Cosmic threat of a collision between the earth and another planet. Dangers coming from space to earth. The largest mass extinction of a living species on Earth
Threat from space. Is planet Earth safe from stone guests from other Galaxies?
Every minute, at great speed, like bullets, only several times faster, uninvited space guests crash into the surface of neighboring planets and the Earth’s satellite, the Moon. Astronomers continually warn about giant boulders whose flight path runs dangerously close to the blue planet. Will the collision be sudden or will scientists be able to prevent a disaster? What dangers does cold space pose? And can earthlings really resist attacks from comets and asteroids?
People have invented vaccines for previously incurable diseases, managed to deceive nature and, thanks to medicine, increase life expectancy. They build roads at an altitude of thousands of meters among rocks and restless volcanoes, cut underwater tunnels for high-speed trains and look with interest at Mars as a future colony of earthlings. But it turned out to be impossible to conquer space, unravel its secrets and be prepared for the invasion of stone fragments. The real threat to humanity is not on Earth, scientists are sure.
An example of human helplessness was the sudden fall of the Chelyabinsk meteorite, which turned out to be impossible to predict. And to prevent destruction - even more so. The meteorite would have shifted by a couple of degrees, the speed would have been a little higher, and a real catastrophe would have been inevitable. The way humanity got off after its fall was nothing short of luck, experts in the field of astronomy and physics assure. But how many other similar or several hundred times more threats are located very close to Earth?
Asteroids are coming back
12 years ago, the asteroid Apophis flew near the Earth, scientists carefully studied its trajectory, dimensions and calculated the likelihood of a collision. By the way, it turned out to be practically equal to zero. But such studies made it possible to find out when the stone guest will visit the solar system again. And what are its actual dimensions? It turned out that Apophis will return very soon - in 2029, scientists are sure, it will fly very close, so that it will be possible to see the asteroid through a regular telescope. Such closeness to the Earth’s orbit is dangerous because the Earth’s gravity can influence all objects approaching it; if you can’t pull a huge boulder, you can easily change its trajectory. And then, upon returning after a few years, the giant’s route may pass even closer to the planet. Ultimately, an asteroid that flew by, for example, back in the 50s of the last century, may end up in the earth’s atmosphere on its next return. True, despite this, some scientific publications are skeptical about “asteroid disasters”, accusing everyone who spreads rumors about the approach of the next “killer asteroid” of wanting to promote themselves and launch a well-rehearsed horror story among everyone. One of these publications even contacted NASA directly so that they publicly made an official statement about the presence of any real threats to the planet from asteroids in the next few years. By the way, American scientists have confirmed this fact; according to all calculations available to NASA, there will be no major collisions for at least a hundred years. Enough for our lifetime!
Black holes
If everything is more or less clear with asteroids, then with “wormholes”, or in other words - black holes, there is no clarity at all. Perhaps the main reason is that it is not possible to study them. And how forces operate and the laws of physics work in this cosmic body is known only approximately. Recently, the results of astrophysical research were published in one of the foreign journals, the text talked about a “suspicious eruption of matter from a black hole” only 105 million light years from Earth. In other words, without scientific terms, a substance resembling gas came out of the black hole, only heated to a million degrees Celsius. In other words, such powerful energy, if it does not “reach” our system, will significantly affect it. And when the effect is visible to the naked eye, again, it is difficult to calculate. Scientists even joke that there are plenty of black holes in our Galaxy and they need to be studied as efficiently as possible. They suck in planets, emit hot gas or “devour” stars - until the matter is studied, it is not possible to prevent a catastrophe or predict it.
Gamma radiation will burn the planet to the ground
Such clots of radioactive energy appear as a result of the explosion of stars, scientists explain. Even if the star is located several million light years from our system, the flashes after the explosion are clearly visible. In addition, these gamma rays are comparable in destructive power to a nuclear strike directly from space. Their power is capable of burning the atmosphere and all life on the planet. True, if they “reach out.” A barrier of several million light years is a significant argument in favor of Earth.
Hot Sun
One of the most popular versions and scenarios for disaster films is the whims of our star-nurse - the Sun. It is no wonder that without it, life on the planet would be impossible. Scientists believe that the temperature of our planet is gradually increasing, not like on a hot frying pan, but nevertheless, after some thousands of years the temperature will be higher, which means the size of the Sun will also increase. Accordingly, along with this, the Earth's climate will change - the oceans will begin to evaporate, depriving all living things of the necessary moisture. In any case, no one promised the Earth a happy existence until the end of time. According to another version, the Sun, on the contrary, is cooling down and this scenario also does not bode well. Having turned into a white dwarf, the star will not be able to provide light and heat to nearby planets. And life on Earth will also be imprisoned by permafrost.
The earth is surrounded. How many threats?
It is known that there are about 6,200 objects dangerously close to the Earth; all of them will sooner or later fly by or have already passed nearby, and any change in their trajectory promises a collision. What is the probability of such a meeting? “Dangerous proximity” is a designation of a distance when a collision is possible if the trajectory changes. Those. there are several main components here that do not guarantee a real threat - “in case” and “possibly”. The probability of a scenario where, under the influence of external factors, a large asteroid suddenly heads towards Earth is 1: 10,000,000. In fact, NASA employees monitor every space object very closely, however, lack of funding also plays a role. Taking control of every celestial body is unrealistic. But those that may pose a threat to the Earth are in a special register. Scientists ignore only those objects whose dimensions are less than one kilometer, mostly because there is no financial opportunity and sufficient human resources. Therefore, it is problematic to detect an asteroid in time, which can make noise, even if it does not destroy the planet. So far, only very small asteroids have passed close to the Earth, the fall of which does not promise any trouble. So, for example, on November 6, 2009, a baby asteroid named 2009VA, whose diameter was less than 10 meters, flew by at a distance of less than 14 thousand kilometers from Earth. And one of the last uninvited guests, 2014RC, flew at a distance of almost 40 thousand kilometers, its diameter was more than 20 meters. At least, as astronomers assure, cases such as the Chelyabinsk meteorite are ordinary, and perhaps even if they were seen in the telescope of a large observatory, no one would pay much attention to it. After all, the dimensions of the object do not fall under the critical criteria. However, space incidents once again remind humanity who is boss in the Universe. Instead of inventing new smartphones and driving more firmly into the piles of another international corporation, it would be worth thinking about the development of the space program. After all, the future of humanity lies in discoveries, and many of them are beyond the Earth’s orbit.
The Earth can be threatened by objects that approach it at a distance of at least 8 million kilometers and are large enough not to be destroyed when entering the planet’s atmosphere. They pose a danger to our planet.
Until recently, the asteroid Apophis, discovered in 2004, was called the object with the highest probability of colliding with the Earth. Such a collision was considered possible in 2036. However, after Apophis passed by our planet in January 2013 at a distance of about 14 million km. NASA specialists have reduced the likelihood of a collision to a minimum. The chances, according to Don Yeomans, head of the Near-Earth Object Laboratory, are less than one in a million.
However, experts have calculated the approximate consequences of the fall of Apophis, whose diameter is about 300 meters and weighs about 27 million tons. So the energy released when a body collides with the surface of the Earth will be 1717 megatons. The strength of the earthquake within a radius of 10 kilometers from the crash site can reach 6.5 on the Richter scale, and the wind speed will be at least 790 m/s. In this case, even fortified objects will be destroyed.
Asteroid 2007 TU24 was discovered on October 11, 2007, and already on January 29, 2008 it flew near our planet at a distance of about 550 thousand km. Thanks to its extraordinary brightness - 12th magnitude - it could be seen even in medium-power telescopes. Such a close passage of a large celestial body from Earth is a rare occurrence. The next time an asteroid of the same size will approach our planet will only be in 2027.
TU24 is a massive celestial body comparable to the size of the University building on Vorobyovy Gory. According to astronomers, the asteroid is potentially dangerous because it crosses the Earth's orbit approximately once every three years. But, at least until 2170, according to experts, it does not threaten the Earth.
Space object 2012 DA14 or Duende belongs to the near-Earth asteroids. Its dimensions are relatively modest - a diameter of about 30 meters, a weight of approximately 40,000 tons. According to scientists, it looks like a giant potato. Immediately after the discovery on February 23, 2012, it was found that science was dealing with an unusual celestial body. The fact is that the asteroid’s orbit is in a 1:1 resonance with the Earth. This means that the period of its revolution around the Sun approximately corresponds to an Earth year.
Duende may remain close to Earth for a long time, but astronomers are not yet ready to predict the behavior of the celestial body in the future. Although, according to current calculations, the probability of Duende colliding with the Earth before February 16, 2020 will not exceed one chance in 14,000.
Immediately after its discovery on December 28, 2005, asteroid YU55 was classified as potentially dangerous. The diameter of the space object reaches 400 meters. It has an elliptical orbit, which indicates the instability of its trajectory and unpredictability of behavior.
In November 2011, the asteroid already alarmed the scientific world by flying up to a dangerous distance of 325 thousand kilometers from the Earth - that is, it turned out to be closer than the Moon. Interestingly, the object is completely black and almost invisible in the night sky, for which astronomers nicknamed it “Invisible”. Scientists then seriously feared that a space alien would enter the earth's atmosphere.
An asteroid with such an intriguing name is a long-time acquaintance of earthlings. It was discovered by German astronomer Carl Witt back in 1898 and turned out to be the first near-Earth asteroid discovered. Eros also became the first asteroid to acquire an artificial satellite. We are talking about the NEAR Shoemaker spacecraft, which landed on a celestial body in 2001.
Eros is the largest asteroid in the inner Solar System. Its dimensions are amazing – 33 x 13 x 13 km. The average speed of the giant is 24.36 km/s. The shape of the asteroid is similar to a peanut, which affects the uneven distribution of gravity on it. The impact potential of Eros in the event of a collision with the Earth is simply enormous. According to scientists, the consequences of an asteroid hitting our planet will be more catastrophic than after the fall of Chicxulub, which allegedly caused the extinction of the dinosaurs. The only consolation is that the chances of this happening in the foreseeable future are negligible.
Asteroid 2001 WN5 was discovered on November 20, 2001 and later fell into the category of potentially dangerous objects. First of all, one should be wary of the fact that neither the asteroid itself nor its trajectory have been sufficiently studied. According to preliminary data, its diameter can reach 1.5 kilometers.
On June 26, 2028, the asteroid will once again approach the Earth, and the cosmic body will approach its minimum distance - 250 thousand km. According to scientists, it can be seen through binoculars. This distance is enough to cause satellites to malfunction.
This asteroid was discovered by Russian astronomer Gennady Borisov on September 16, 2013 using a homemade 20 cm telescope. The object was immediately called perhaps the most dangerous threat among celestial bodies to the Earth. The diameter of the object is about 400 meters.
The asteroid's approach to our planet is expected on August 26, 2032. According to some assumptions, the block will sweep just 4 thousand kilometers from the Earth at a speed of 15 km/s. Scientists have calculated that in the event of a collision with the Earth, the explosion energy will be 2.5 thousand megatons of TNT. For example, the power of the largest thermonuclear bomb detonated in the USSR is 50 megatons.
Today, the probability of an asteroid colliding with the Earth is estimated at approximately 1/63,000. However, with further refinement of the orbit, the figure may either increase or decrease.
The most famous example of an evolutionary shift caused by astronomical events is the extinction of the dinosaurs, which was caused by the fall of a giant meteorite 66 million years ago. This hypothesis was first proposed by Luis Alvarez, his son geologist Walter and their colleagues in 1980.
Researchers have discovered that sedimentary rocks that formed around the world during the extinction of the dinosaurs contain large amounts of the rare element iridium. Scientists have suggested that the iridium could have come from dusty debris from a meteorite that crashed into the Earth. The asteroids, which were the most likely source of the iconic meteorite, contain much more iridium than Earth.
How exactly such a fall could have killed the dinosaurs -. But there are quite a lot of possibilities.
The released energy could cause global forest fires. The researchers calculated that to deliver the required amount of iridium, the meteorite would have to be about 10 kilometers across. The impact of such a monster would release millions of times more energy than a hydrogen bomb. Moreover, dust and debris released into the air could block sunlight and set off a gradual decline in temperatures over the next few years.
In 1991, the impact hypothesis received new impetus when scientists discovered an impact crater more than 160 kilometers wide at the site of Chicxulub on the Yucatan Peninsula in Mexico. Its geological age coincided exactly with the period of extinction.
How exactly the meteorite impact influenced the demise of the dinosaurs is not fully understood; there is evidence that they were already close to it. Nevertheless, it is logical to assume that such a powerful event should have left some imprint on evolutionary history. And this discovery has raised concerns about the possibility of a destructive meteorite falling today.
Additionally, meteorite impacts are not the only explanation for the extinctions that occurred 66 million years ago.
Tokuhiro Nimura is a scientist with the Japan Spaceguard Association, which formed to observe near-Earth objects that could impact the planet. In March 2016, Nimura and colleagues suggested that the extinctions, global cooling, and iridium layer may have been caused by the solar system passing through a molecular cloud: one of the large clouds of gas and dust in space from which stars form. As dust accumulated in the atmosphere, it formed a haze that reflected sunlight and cooled the planet.
The basic idea goes back to the proposal of British astronomer William McCrea, put forward by him in 1975. He thought that if the Earth passed through an interstellar dust lane, it would trigger an ice age. At the same time, astronomers Mitchell Begelman and Martin Rees noted that such dust could affect the way solar wind particles move as they enter the atmosphere. our planet, and expose the planet to high doses of radiation, further exacerbating extinctions and climate change.
Now Nimura has resurrected McCree's idea, arguing that the Chicxulub fall was not catastrophic enough to cause all the end-Cretaceous extinctions.
However, this is mostly speculation right now.
"The idea struck me as very interesting and plausible, but it is not yet developed and has no clear supporting evidence," says astronomer Martin Beach of Campion College at the University of Regina in Saskatchewan, Canada.
This 66 million year event was just one of several known "mass extinctions" in which many species across the planet suddenly disappeared.
The largest mass extinction of a living species on Earth
The largest extinction event occurred at the end of the Permian period 252 million years ago, when at least 96% of all life on Earth became extinct. All modern life came from the surviving 4%, so it is clear that evolutionary history could have been completely different if that extinction had not happened. When species die off, those given the opportunity evolve and make the most of it, dictating a diversity of species that would not otherwise exist.
Paleontologists have long debated what caused these mass extinctions.
It is possible that, like smaller population declines, they may be an integral part of the functioning of ecosystems. Because all life is interconnected, a small shift in one population can cause a domino effect, sending shock waves through the entire system.
But it is more likely that at least some mass extinctions were caused by external influences on the living world.
One such mass extinction occurred at the end of the Triassic period. About half of all species on Earth have disappeared. This event could also be caused by an increase in volcanic activity, climate changes, but most likely by a meteorite fall.
Such catastrophic events cannot be the result of pure chance, like a random comet or asteroid hitting the Earth. Instead, cosmic circumstances may systematically bring such objects closer to our world.
The most famous of these ideas is that the Sun has a dim companion star that is so distant that it has never been observed directly. This star, the Nemesis, or Death Star, periodically attracts chunks of icy rock from the outskirts of the solar system and sends them to hang out in our neighborhood.
This idea was proposed in 1984 by two teams of astronomers: Daniel Whitmire and Albert Jackson and Mark Davis, Richard Muller and Pete Hut. They were all starting from a discovery that had happened earlier that year: mass extinctions had occurred at regular intervals of about 26 million years over the past 500 million years.
Mystery of the Solar System: Nemesis
So perhaps the gravitational pull of Nemesis, which circles the Sun in an orbit 1.5 light-years away, has been disrupted by the Oort cloud: a collection of icy objects that lies 0.8 to 3 light-years beyond Pluto's orbit, loosely bound by gravity Sun. The Oort Cloud is the source of "long-period" comets that return to the inner Solar System every two hundred years or so.
Nemesis would be a tiny star, perhaps a red or even a brown dwarf no larger than Jupiter. That's why she was never noticed. At such a distance it would be difficult to see even with our most powerful telescopes.
But this is not the only problem with the Nemesis theory.
In a study published in 2010, astrophysicist Adrian Melott of the University of Kansas and paleontologist Richard Bambach of the Smithsonian Institution in Washington, D.C., decided to take a fresh look at the fossils using the latest data. They confirmed that mass extinctions occurred every 27 million years. But this picture is too ordinary to fit into the Nemesis idea. Such a distant dwarf would inevitably be influenced by other stars nearby, producing a less constant stream of comets.
No, the scientists decided. Mass extinction waves must be caused not by a companion star, but by another planet.
Does Planet Nine exist?
In 1985, Whitmire and his colleague John Matese proposed that there might be a relatively small, rocky planet five times more massive than Earth orbiting in the solar system far beyond Neptune. This planet can attract comets, not from the Oort cloud, but from the closer Kuiper belt. This is another disk of icy rocks at the edge of the solar system, Pluto and its moon Charon are recognized as its members. Whitmire and Matese called their hypothetical object "Planet X."
It is possible that we have not yet been able to find another planet in the solar system that is larger than Earth. Before the New Horizons spacecraft reached Pluto and Charon in 2015, we had fairly poor images of these objects, and we were just beginning to look for larger bodies in the Kuiper Belt. If Planet X is dark and does not reflect light, it could very well elude our telescopes.
Moreover, in January 2016, astronomers suggested that in the solar system there may be, beyond Neptune, with a mass of 10 Earth's. The proposal grew from observations of visible Kuiper belt objects that appeared to .
If this planet exists, it is unlikely to do what Planet X claims. But history shows there is a lot we don't know about our own backyard.
Whitmire, now at the University of Arkansas, decided to take the Planet X hypothesis even further. In 2015, he showed that this idea is consistent with the 27-million-year extinction period observed by Melott and Bambach. Moreover, Whitmire says that the second such object is Planet Y? - could explain another fluctuation in the fossil record.
This picture was noticed by Richard Muller and Robert Rohde in 2005. They found that marine species diversity rises and falls every 62 million years: this fluctuation must be caused by either a change in extinction rates or speciation rates.
Comet waves caused by "hidden" planets could be an explanation for such patterns, Melott says. But he adds that other, more distant cosmic events may be behind these fluctuations.
In 2007, Melott and his colleague Mikhail Medvedev said the 62-million-year pulse could be caused by a regular feature of our solar system's journey through the Milky Way.
Our galaxy is shaped like a dish. As it rotates, the Sun rises and falls on the galactic plane, like a horse on a carousel. These changes in position can change the amount of cosmic rays that stream through the solar system and hit Earth.
Cosmic rays and their impact on life
Cosmic rays are high-energy subatomic particles, protons and electrons, flying through space. It is believed that they must be born in high-energy astronomical processes. Some are born in supernovae: stars that explode when their fuel runs out. Others are born in black holes at the centers of other galaxies.
There are different ways in which they could have influenced the Earth's environment and our evolution.
Cosmic rays themselves can be harmful. When they collide with molecules in the air, they create showers of particles that can cause mutations in DNA. This is usually bad for life. However, low mutation rates can actually increase diversity, making life more diverse.
Cosmic ray collisions can also change the chemical composition of the atmosphere. They can produce electrically charged particles that influence the formation of clouds and therefore the climate, or they can destroy the ozone layer, which protects the Earth from the harmful effects of the sun's ultraviolet rays.
Since many cosmic rays are thought to be created by supernovae within our galaxy, the up-and-down wobble of our solar system could change the flow of cosmic rays, with all the implications for life on Earth.
However, it is rather strange that these effects only appeared among marine fossils. In any case, one would expect that organisms living in the sea are better protected from showers of harmful particles than those living on land.
Even Melott now thinks that this idea cannot explain the 62 million year cycle in the fossil record. In 2011, he suggested that it may be an innate geological "pulse of the Earth", perhaps related to changes in tectonic activity.
There is a similar pattern of changes in the composition of marine sediments, Melott says. This is what would be expected from changes in the rates of mountain building and erosion caused by shifts in the movement of tectonic plates.
Death rays from space seem to be a good reason for some of the evolutionary shifts seen in the fossil record.
We are constantly exposed to low levels of cosmic rays. But one supernova could release such a deadly explosion of these particles that it would sterilize the planet if it were unlucky enough to be nearby and in the right direction.
How can the birth of supernovae lead to the extinction of all life on Earth?
Stars go supernova all the time; during this, they can temporarily glow brighter than entire galaxies. We see many supernovae every year in other galaxies, but in our own galaxy, people last saw a supernova 140 years ago. Another, which was born in 1572, was so bright that the astronomer Tycho Brahe saw it with the naked eye and successfully described it.
Supernova Tycho was safely distant: 7,500 light years away. If such an explosion happened much closer to us, it would become a serious disaster. The earth would be shaved bald by a stream of particles and x-rays and gamma rays.
Has this ever happened?
It is believed that a supernova would have to be within 30 light years to have devastating consequences for Earth. Not many stars are this close to us.
However, in 2002, research by astronomers showed that there may have been 20 supernovae within 420 light-years of Earth in the last 11 million years, from just one group of stars. Such events could well have left their mark on the fossil record.
They definitely left traces in the sedimentary rocks. Supernovae scatter the outer layers of an exploding star into space, including some atoms that are not abundant on Earth.
One such telling supernova product is iron-60, which does not occur naturally on Earth. In 1999, physicists discovered high levels of iron-60 in geological structures in the deep ocean - ferromanganese crusts formed over the past 5 million years. Iron-60 has also been found in lunar soil and appears to have come from two supernovae 320 light-years away, seven and two million years ago respectively.
The latest explosions appear to have left traces in the fossil record.
In a study published in August 2016, astrophysicist Sean Bishop of the Technical University of Munich and colleagues reported the discovery of iron-60 in fossil iron oxide crystals. These crystals were originally made by bacteria, which use magnetic oxide to align themselves with the Earth's magnetic field. Iron-60 began to appear in such fossils in marine sediments formed 2.6-2.8 million years ago.
Life could have been disturbed by these supernovae.
X-rays and gamma rays coming from such a distant source are not a problem in themselves. "They do not enter our atmosphere and therefore cannot directly lead to sterilization or mass extinctions," Bishop says.
But he also says those rays can create an indirect danger by damaging the ozone layer. “With the reduction of the ozone layer, as far as we know since the Antarctic ozone hole, ultraviolet light from the Sun will penetrate the Earth's surface and may become a problem for organisms.”
According to calculations by astronomer Narciso Benitez and his colleagues, supernovae at such distances could potentially deplete atmospheric ozone.
Moreover, in a July 2016 study, Melott and his colleagues estimated that cosmic rays from supernovae could increase the number of high-energy neutrons and muons reaching the ground, tripling the total radiation dose to terrestrial organisms. This could trigger cancer mutations and also trigger climate change, scientists say.
2.6 million years ago, a small mass extinction did occur, at the turn of the Pliocene and Pleistocene epochs. But we cannot say for sure that supernovae “had a hand in this.”
In fact, there is no direct evidence that supernovae ever interfered with the evolutionary history of life, Bishop says. "Millions of years from now this will be incredibly difficult to prove." For example, there is no way to collect and study fossilized DNA for mutations after such a long period of time, let alone compare it before and after the event.
However, there is another type of cosmic explosion, even more powerful.
Gamma radiation emissions
The skies are sometimes rent by explosions called gamma-ray bursts: extremely intense explosions that release gamma rays that last from a fraction of a second to several hours. Gamma-ray bursts are among the most energetically powerful events in the Universe. They are born when particularly powerful stars explode.
Fortunately, gamma-ray bursts have so far only been seen in very distant galaxies. But if one of these were born nearby, the supernova would be fireworks in comparison. To make matters worse, we were unlikely to be able to detect its approach in advance, no more than a couple of hours in advance. Fortunately, Melott says gamma-ray bursts within 10,000 light years in the area occur about once every 170 million years.
Although this is quite rare, the Earth has existed long enough to have been hit many times. In 2004, Melott suggested that the end-Ordovician mass extinction 440 million years ago may have been associated with a gamma-ray burst. And everything went according to plan: X-rays and gamma rays severely damaged the ozone layer and triggered global cooling due to the formation of thick smoke from nitrogen oxides in the atmosphere.
Melott argues that the end-Ordovician extinction pattern fits into this picture. For example, shallow-sea marine organisms, which were more exposed to ultraviolet radiation than deep-sea ones, suffered more severely. In addition, the climate has become noticeably colder.
Could this happen again? The Earth has about two billion years left to live, after which the Sun will expand and make the planet uninhabitable. In a 2011 analysis, Beach estimated that about 20 supernova events and one nearby gamma-ray burst could occur during that time and cause damage. But these are mildly alarming numbers.
Plus, Melott says we might be able to see supernovae in advance as we measure the ages of nearby stars. The closest one that could detonate soon - within the next million years - is Betelgeuse in the constellation Orion. She's too far away to do any damage.
Beach says it could theoretically be possible to engineer stars to avoid catastrophic explosions. “If a civilization knew that a supernova was going to explode in its vicinity, one of its options for survival would be to try some kind of super-astro-engineering project.”
For example, they could deflect the explosion by causing the star to lose mass or by mixing in some material that could slow its collapse. “I don’t know how such a project could be physically carried out, but the physics of this situation and what needs to be done to extend the life of the star are quite well understood.”
Beach suggests that stars that are at risk of going supernova could be good places to search for aliens. If such a star begins to behave strangely, this may be a sign of deliberate alteration.
Cosmic threats to life on Earth may be even more exotic.
Dark matter
In her 2015 book, Dark Matter and Dinosaurs, physicist Lisa Randall of Harvard University suggested that a mysterious cosmic substance—dark matter—could be the ultimate dinosaur killer.
Dark matter doesn't interact with light, so we can't see it directly. It affects ordinary matter only through gravity: it has mass, so it attracts matter like any ordinary substance. We don't know what dark matter is. No one has ever found a single particle of it. But most physicists and astronomers are confident of its existence. If it were not there, galaxies would not rotate so quickly and would not fall apart. Dark matter is five times larger than ordinary matter. It is believed that it surrounds each galaxy with a spherical halo.
Randall suggested that certain dark matter is different from the rest.
This "exotic dark matter" can sense another force, like gravity, similar to the electromagnetic force that allows ordinary matter to interact with light. This exotic dark matter could have formed a disk in the galactic plane, and the solar system's passage through this disk could have disrupted the comet's path through the Oort cloud, causing it to collide with Earth 66 million years ago.
Biologist Michael Rampino of New York University expanded on this idea. In a study published in 2015, he suggested that some dark matter particles could be trapped and destroyed in the Earth's core. This released energy, increased volcanic activity, and created the "pulse of the Earth" that Melott had previously linked to extinctions.
Well, maybe so. But some scientists say the ideas are too dubious and would likely not attract much attention if they were put forward by someone less famous than Randall, who is a near-superstar in the field of cosmology.
"We'll have to invent new physics to make this mechanism work," Melott says.
“This argument seems too far-fetched to me,” agrees Beach.
But he adds that while it is unclear whether there actually is a disk of dark matter in our galaxy, “we know so little about the distribution and composition of dark matter in the galactic disk and halo that any assumption within the bounds of our current uncertainty is entirely possible.” So far this is an interesting but dubious idea. Should you trust her?
All of the individual stories we have discussed are unproven, and many of them are controversial. But take a step back and you will have no doubt that in one way or another life on Earth is connected and dependent on cosmic forces. The difficulty is to figure out which cosmic phenomena played a role in a particular case. These factors stretch over such a huge time scale that there is no need to even worry about the impending threat to our survival in this vein. In the foreseeable future, our planet is not threatened by any catastrophic meteorite, although it is certainly worth watching.
But no one says that human civilization is completely protected from cosmic threats.
Melott says the biggest thing we should be wary of are solar flares: sharp flares from the Sun that bombard the planet with particles and radiation. The electromagnetic pulse they produce can paralyze telecommunications.
One such event in 1859 wreaked havoc on early telegraph networks, shocking several operators and causing fires. Today, with our gigantic communications network, the consequences will be devastating. We narrowly escaped this fate in 2012 when a solar superstorm passed us by, but there was a big one in 1989 that knocked out Canada's power grid.
If an event like this can bring a civilization to its knees, it may also leave its mark on the evolutionary record because, ironically, it will stop the latest mass extinction that is currently happening because of us.
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Artem Luchko
It is known for certain that more than 99% of the species of living beings that have ever existed on our planet have disappeared. And it is unlikely that a person will live forever. Asking questions about what threatens our existence, we draw in our heads apocalyptic pictures from sci-fi films about a giant meteorite or an invasion of alien invaders. But there are also less cinematic, but very real scenarios that few people think about. We decided to list some of them in this material.
Solar storms
The slightest malfunction in the operation of our giant thermonuclear reactor - that is, the Sun - can lead to the fact that our planet may simply become either too cold or too hot to support life and the necessary ingredients for it: namely a breathable atmosphere and water in liquid state. The Sun is a fairly constant star compared to most other stars in our Galaxy, but its radiation flux still varies over a relatively stable 11-year cycle. These changes amount to only 0.1%, but even this negligible figure has a rather serious impact on the Earth’s climate.
Moderate storms occur regularly 100-150 times a year, but a solar superstorm can destroy a significant portion of the power grid in developed countries. The most powerful storm in the history of measurements was the storm of 1859, also known as the “Carrington Event”. The coronal ejection was so powerful that the Northern Lights were observed all over the world, even over the Caribbean. A solar storm caused disruption to US telegraph lines. But in the mid-19th century there was no serious electrical infrastructure, but if such a cataclysm had occurred today, it would have disabled high-voltage transformers and left entire countries without electricity, throwing us back a hundred years.
Gamma-ray burst
The Sun is not the only star that poses a threat to our planet. Large-scale cosmic emissions of energy are observed in distant galaxies, they are called gamma-ray bursts. These most luminous electromagnetic phenomena occur during a supernova explosion, when a rapidly spinning massive star collapses into either a neutron star, a quark star, or a black hole. In this case, in a few seconds of the flare, as much energy is released as the Sun releases in 10 billion years.
The sources of these emissions are located at distances of billions of light years from Earth, and in our Galaxy a gamma-ray burst occurs approximately once every million years, but if it occurs close enough to Earth, its consequences will significantly affect all living things. A gamma-ray burst about 3,262 light-years away could destroy up to half of Earth's ozone layer, which is our main defense against ultraviolet radiation, according to a 2004 study. In this case, the rays from the explosion, combined with ordinary solar radiation passing through a weakened ozone “filter,” can cause mass extinction of humanity.
If a gamma-ray burst occurs at a distance of 10 light years (there are about 10 stars within such limits from us), this will be equivalent to the explosion of an atomic bomb on every hectare of the sky, and on half of the planet all life will be exterminated instantly, and on the second half a little later due to secondary effects.
Supervolcanoes
A serious danger lurks in the depths of our planet. It is known that eruptions of so-called supervolcanoes, of which there are about 20 on Earth, can change the climate on Earth and lead to the most dire consequences. One good thing is that on average such eruptions occur once every 100 thousand years.
One of the most dangerous underground forces is the Yellowstone Caldera, which measures about 55 km by 72 km and occupies a third of the territory of the famous national park. Scientists have found that the volcano erupted three times, the last time 640 thousand years ago. The probability of a new giant eruption is estimated by scientists at 0.00014% per year.
The eruption of the Yellowstone volcano threatens all of humanity. According to scientists, a huge cloud will be thrown into the stratosphere, which can hang for a long time, preventing the sun's rays from penetrating the Earth. Reducing the power of solar radiation by half will lead to global crop failure, and the food reserves available on earth will hardly last for a couple of months. The average annual temperature on Earth can drop by 12 degrees and return to its original position only in 2-3 years.
Other smaller volcanoes may pose dire consequences of a different nature. For example, a volcano on the island of La Palma in the Canary archipelago, if it erupts, can cause a giant ocean wave that can flood the Caribbean and vast areas of the US coast. One of the slopes of the volcano is unstable, and if it begins to erupt, a rock weighing half a trillion tons could fall into the ocean. It will cause a wave 650 meters high, which will have no difficulty quickly crossing the Atlantic.
Global pandemic
The population of our planet continues to grow, and more than 50% of people already live in cities. Overpopulation leads to an increase in mutations, and high population density leads to the rapid spread of diseases. Apparently, this trend will only continue, and in the future we should expect the emergence of new terrible epidemics that can kill entire cities.
At the same time, antibiotics are becoming increasingly useless, which is seriously worrying the World Health Organization. The rise of antibiotic resistance threatens to throw humanity back to the era before the invention of penicillin, when the most trivial infection became deadly. “In the absence of swift and concerted action from many stakeholders, our world is entering an era when antibiotics are no longer effective, and common infections and minor injuries that could have been treated for decades are now at risk of killing again,” says WHO Assistant Director-General on Health Security Dr. Keiji Fukuda.
In general, it is not difficult to imagine how a new plague epidemic will break out and doctors will have no way to stop it. Everyone knows what the Black Death is, which raged in the middle of the 14th century and destroyed almost half of the world's population, after which it took 150 years to restore the population. Another terrible pandemic occurred in 1918-1919, when approximately 50 to 100 million people died from the Spanish flu (or about 5% of the population). With the current level of urbanization and the development of transport infrastructure, things will only get worse.
In 2010, a team of epidemiologists built a computer model of the Nipah virus, and then monitored how it would spread and develop. The report on the results of the computer simulation formed the basis of the film “Contagion”. So fantasies about a deadly virus of unknown origin that is rapidly spreading throughout the world may well become a reality.
Resource depletion
No one knows for sure how much oil remains in the depths of our planet. But according to optimistic forecasts, by 2050 half of the world’s oil reserves will already be pumped out (according to released intelligence data). “The first and most pressing problem we will face by then is the end of the era of cheap fossil fuels. It is no exaggeration to say that it is the reserves of cheap oil and natural gas that underlie modern prosperous life,” writes the fatalist writer James G. Kunstler.
The oil crisis will have horrific consequences for which most of the world's population is not prepared. And this process will affect not only industrialized countries. Over time, as oil becomes an increasingly rare resource, more developed countries will have to look for it where it still remains - with their weaker neighbors. A new stage of exploitation of “poor” countries by “rich” countries will begin: more and more armed conflicts will break out in the Middle East and Africa.
A shortage of oil can provoke an acute shortage of other resources necessary for human life. Billions of people will go hungry due to widespread dependence on fossil fuels. Ultimately, this could all lead to a return to subsistence farming.
Perhaps one day humanity will get off the oil needle and replace gasoline with alcohol, which will be extracted from corn or sugar cane. However, there is no known method by which we can produce rare earth metals, and potential substitutes either do not exist in nature or have insufficient properties. And without these substances, we would have no smartphones, no computers, no electric vehicles, or any other electronics, and, accordingly, no progress.
According to calculations by scientists at Yale University in the USA, sources of rare earth metals are being depleted at tremendous speed. Currently, about 95% of all rare earth metals are mined by China, and most recently its government introduced restrictions on the export of certain elements, as well as doubling the price for them for non-Chinese producers.
Gray slime
With the development of technology, humanity should fear that these technologies will get out of control and destroy their creators. One hypothetical threat is what futurists call gray goo (Grey Goo)- self-replicating molecular nanotechnology that does not obey humans.
For the first time, the American scientist Kim Eric Drexler, who is called the “father of nanotechnology,” spoke about the possibility of creating such a substance. The scientist discussed the idea of creating nanorobots in his book “Machines of Creation.” The original idea suggested that microscopic machines could be designed in a laboratory, but could also acquire their properties by chance.
In 2010, DNA-based nanorobots were first demonstrated that can seek out and destroy cancer cells, leaving healthy tissue unharmed. Tiny capsules release the necessary doses of drugs when a target is detected and specifically destroy the “enemy”. As a result, it turned out that these nanorobots can exist for another month after the death of the “master”.
So far, of course, nanocyborgs are being developed exclusively for the benefit of people, but in theory they are quite capable of both creating and destroying. If, for some reason, nanobots get into the biosphere and begin to multiply endlessly, using everything they can get to as material to create their copies, in fact, they can begin to absorb everything around them, including the planet itself. At the same time, the hypothetical “gray goo” will be very difficult to destroy, since one surviving replicator will be enough for it to start reproducing again. If such a robot ends up in the World Ocean, it will be simply impossible to destroy it.
Nuclear holocaust
While there are 7 countries in the world that have nuclear weapons, the likelihood of a nuclear war breaking out cannot be zero, despite the fact that it could lead to the extinction of humanity or the end of modern civilization on Earth. The reasons for this threat are quite obvious: a nuclear explosion is accompanied by a destructive shock wave that erases everything around it along the way, scorching light radiation and penetrating radiation that causes irreversible changes in matter. People, even those who have not received significant injuries directly from the explosion, are likely to die from infectious diseases and chemical poisoning. There is a high probability of being burned in fires or being walled up in rubble.
A nuclear explosion causes a disturbance in the electromagnetic field, which will disable electrical and radio-electronic equipment - that is, all communication lines, transformers, semiconductor devices, which will lead to the loss of all modern technologies.
Despite all the risks to which civilization will be exposed, analysts suggest that billions of people will nevertheless be able to survive a global thermonuclear war. But after it ends, nuclear winter may begin. Widespread explosions and fires will carry gigantic amounts of smoke and soot into the stratosphere. As a result, the sun's rays will be reflected from these particles, and the temperature on the planet will drop to arctic temperatures everywhere, and the surviving population will have to adapt to the new harsh conditions.
Ignorance and stupidity
The most underestimated threat to any society is ignorance (unconscious or conscious) combined with passivity and laziness. Both types of ignorance are fed by the media - the main tools of politicians and corporations.
It is the “cult of ignorance” that is the reason that in the 21st century in the world there are religious fundamentalists, racists, people who worship power and demonize all those who do not. It is because of widespread ignorance that there are people everywhere who deny global warming and exploit others for personal profit.
During the “fed years”, ignorance increases, and the importance and necessity of education becomes less obvious. The younger generation, enjoying the benefits of the system that was built by their ancestors, gradually forgets how and why this system was built. In the end, incompetent people gain power with the support of the majority, thereby putting the foundations of the system itself at risk.
Populism and lack of competence pose a real danger to humanity. For example, researchers from the USA (a country that is currently at the peak of prosperity as a result of technological advances and effective economic policies in the 19th and 20th centuries) suggest that this peak can be interpreted as the beginning of a decline. If only because former US vice-presidential candidate Sarah Palin is not familiar with basic scientific theories.
The figure above shows a graph in which the development of education is marked in blue, and the economic development accompanying it in red from the times of Ancient Greece to the present day. Although the figure is quite speculative, such pessimistic views are quite common among futurists.
Max Tegmark, a professor of physics at the Massachusetts Institute of Technology, also believes that human stupidity is the biggest problem for all of humanity, and artificial intelligence is its biggest existential danger. People with limited intellectual functioning, ignoring the potential catastrophic consequences, may allow artificial intelligence to develop into something capable of destroying humanity.
And civilization or even the entire Universe. The threat can be either imaginary or real. For some, the expression “end of the world” evokes fear, panic and horror, while others consider it absurd. However, there is even a whole list of upcoming apocalypses. Before we talk about them, we should know the possible causes of the end of the world.
Possible causes of the apocalypse
There are many reasons for the end of the world. Some of them seem truly impossible, while others could well lead to the death of all living things.
- First of all, this is war. Biological or even nuclear.
- Secondly, possible genetic diseases that will eventually destroy the whole world, taking over it so much that attempts to cure humanity will be useless.
- Thirdly, famine, which, for example, can occur in case of overpopulation.
- Fourthly, an environmental disaster, when the cause of the death of a people is the people themselves. That is why environmentalists all over the world are calling to protect their planet. Take, for example, the destruction of the ozone layer - all this is quite dangerous.
- Another problem that is caused by man himself is nanotechnology getting out of control.
- Sixthly, a sharp change in climate. Global cooling or warming will lead to the death of almost all life on the planet.
- The causes of the apocalypse can also be the eruption of a supervolcano, the fall of a huge asteroid, or a strong solar flare.
All these and many other reasons can radically change life on Earth, and possibly even lead to its death. How dangerous are these events and should we expect an apocalypse in the near future? We'll talk about this and much more further.
The end of the world according to the Mayan calendar
First, let's remember 2012, when the whole world literally lived in fear of the end of the world according to the Mayan calendar. According to numerous sources, the apocalypse was supposed to happen in 2012. Why was everyone waiting for him on this particular day and where did such a mythical figure come from?
The thing is that the people who once lived in Central America, the so-called Mayan people, kept a calendar that ended on this date. Lovers of mysticism and various kinds of clairvoyants said that the world would supposedly end on this day. Such statements, which simply blew up the Internet, scared millions of people. What did the earthlings, filled with fear, not expect: volcanic eruptions, strong earthquakes and tsunamis, and all this in one day.
“Silence and darkness will come to the world, and humanity will be destroyed,” the Mayans said. Now this seems absurd, just as it did for geophysicists in 2012. They still said back then that it was simply impossible. An interesting fact is that people were offered to survive during a terrible apocalypse by surviving it in a secluded place with huge supplies of food. Even the statement about the possible death of humanity was used by supermarkets around the world, which was very beneficial for them. The gullible people fearfully purchased food for months in advance.
But not only supermarkets made money from such news. In many cities, even special bunkers were built that supposedly could save people from the upcoming apocalypse. Living in such a safe place cost a lot of money. But, as it turned out, the apocalypse was not destined to happen, which is not at all surprising, because we have already survived several ends of the world and still live happily. Anthropologist Dirk Van Turenhout explained the situation by saying: “This is not the end, it’s just one calendar giving way to another.”
Another loud end of the world
The apocalypse was also expected in 2000. People believed that with the transition to the new millennium the very end of the world would come, and they even came up with a reason why this would happen - a parade of planets, the appearance of a second Moon. According to some reports, an asteroid was supposed to fall.
The end of the world in this case would come when it collides with the Earth. We have entered the new millennium, but the end of the world has never happened. Then astronomers and predictors decided to postpone the expected apocalypse to 2001. What is its reason?
Apocalypse-2001
Here things get even more interesting. “On August 11, 2001, planet Earth and the entire solar system will be sucked into a black hole,” this is an interesting forecast made by American astronomers. The following prediction was also made by an American scientist. According to him, in 2003 the end of the world will occur due to the collapse of the Earth. Apparently, few people believed the latest apocalypse, otherwise how can one explain the fact that there was almost no mention of it in the media. After this prediction, humanity lived quietly for five whole years, after which it became known about the next end of the world.
End of the World - 2008
This year several apocalypse scenarios have been announced.
One of them was the fall of a huge asteroid to Earth, the diameter of which was 800 meters. Another reason could be the launch of a huge collider. This made earthlings worry much more than the forecast of an asteroid fall. Fortunately, the excitement was in vain, but the fear left us for a short time. People started saying that the end of the world would happen in 2011. As it will be?
2011
This version turned out to be much more interesting. American Harold Camping predicted that on May 21 the dead would rise from their graves. Those who deserve to burn in hell will remain on earth and survive a number of terrible natural disasters: earthquakes, floods, tsunamis, and only then go to another world. The version itself is absurd, but, nevertheless, Harold Camping received a huge number of supporters, especially in the USA.
The preacher even gave hope that there would be a small percentage of survivors, consisting of his followers. An interesting fact is that a US PR company organized the release of huge posters with a statement about doomsday. After nothing like this happened on the expected day, the prophet himself moved the date of the end of the world to October 21 of the same year, explaining that the incident happened morally, and all that now needs to be done is to wait for the real, already final end of the world .
According to his new forecasts, it was supposed to happen in exactly 5 months. Despite Harold's predictions, the end of the world never came, and thousands of people calmly exhaled and continued to live. When Camping realized that his forecast was wrong, he admitted guilt and even apologized.
And again about 2012
Well, the most anticipated on the list of the ends of the world is the apocalypse of 2012. It has already been mentioned above. Perhaps discussions of this end of the world are the loudest of all.
This date, indeed, frightened millions of people all over the world, because not only the Mayan calendar spoke about the events of that year. Predictions about terrible events were made by Nostradamus and Vanga, known throughout the world for their prophecies. What did they really mean? Natural disasters, the beginning of a new life or the death of the planet? All this remains a mystery. But Patriarch Kirill said about 2012 and the apocalypse in general that it is not worth waiting for, because Jesus Christ does not give us instructions about any dates.
Will there be some kind of rebirth? Perhaps, but no one knows when it will come. Despite everything, people continue to listen to predictions and believe in the end of the world. So what threatens the Earth in the near future?
What do they promise in the future?
The next end of the world is scheduled for 2021. This statement was made by the SaraInform news agency, which presented a new list of the ends of the world. Magnetic field reversal is the reason for the end of the world in 2021. Or maybe not even the end, because they promise that not all of humanity will perish, but only a large part of it.
Scientists assume that this end of the world will not happen, but there will be another, and it will happen in 2036. In their opinion, an asteroid called Apophis will fall on Earth, but again, this information is not objective, since the asteroid may diverge from the Earth.
Another apocalypse is supposed to happen in 2060. Newton himself predicted it back in 1740 from the holy book. And in 2240 the planetary epochs will change. This is what scientists who lived in different centuries said. And also, in their opinion, the era of the Sun should end this year.
Other possible doomsdays are dated to 2280, 2780, 2892 and 3797. By the way, the last apocalypse was predicted by Nostradamus, therefore, we are talking about the fact that he did not think about the end of the world in 2012 as the end of all life in general. In his letter to his son, he wrote that the Sun would supposedly absorb the Earth, exhausting all the hydrogen and reaching incredible volumes.
Other dates of the apocalypse are not yet taken seriously, but no one knows what will happen over time. By the way, these are not all dates, there are some others - intermediate ones, but no one pays attention to them, since the probability of incidents is almost zero.
Will the world end?
We have reviewed the list of the ends of the world; to believe or not to believe in forecasts is everyone’s personal choice. We can say with 100% certainty: no one knows and cannot know whether there will be an apocalypse and when exactly. What awaits the Earth in the near future? Who to trust: predictors or scientists? Each has their own point of view, however, it is worth noting that the information of the latter is more reasoned and objective.
Instead of guessing, it is better to think about the real harm we are doing to our planet. For example, each of us can improve the environmental situation, because the Earth is really in a dangerous state, and people themselves are to blame for all this.