The previous post assessed the danger of an asteroid threat from space. And here we will consider what will happen if (when) a meteorite of one or another size does fall to Earth.
The scenario and consequences of such an event as the fall of a cosmic body to Earth, of course, depends on many factors. Let's list the main ones:
This factor, naturally, is of primary importance. Armageddon on our planet can be caused by a meteorite 20 kilometers in size, so in this post we will consider scenarios for the fall of cosmic bodies on the planet ranging in size from a speck of dust to 15-20 km. There is no point in doing more, since in this case the scenario will be simple and obvious.
Small bodies of the Solar System can have different compositions and densities. Therefore, there is a difference whether a stone or iron meteorite falls to Earth, or a loose comet core consisting of ice and snow. Accordingly, in order to cause the same destruction, the comet nucleus must be two to three times larger than an asteroid fragment (at the same falling speed).
For reference: more than 90 percent of all meteorites are stone.
Also a very important factor when bodies collide. After all, here the transition of kinetic energy of motion into heat occurs. And the speed at which cosmic bodies enter the atmosphere can vary significantly (from approximately 12 km/s to 73 km/s, for comets - even more).
The slowest meteorites are those that catch up with the Earth or are overtaken by it. Accordingly, those flying towards us will add their speed to the orbital speed of the Earth, pass through the atmosphere much faster, and the explosion from their impact on the surface will be many times more powerful.
At sea or on land. It is difficult to say in which case the destruction will be greater, it will just be different.
A meteorite may fall on a nuclear weapons storage site or a nuclear power plant, then the environmental damage may be greater from radioactive contamination than from the meteorite impact (if it was relatively small).
Doesn't play a big role. At those enormous speeds at which a cosmic body crashes into a planet, it does not matter at what angle it will fall, since in any case the kinetic energy of movement will turn into thermal energy and be released in the form of an explosion. This energy does not depend on the angle of incidence, but only on mass and speed. Therefore, by the way, all craters (on the Moon, for example) have a circular shape, and there are no craters in the form of trenches drilled at an acute angle.
They completely burn up in the atmosphere, leaving a bright trail several tens of kilometers long (a well-known phenomenon called meteor). The largest of them reach altitudes of 40-60 km, but most of these “specks of dust” burn up at altitudes of more than 80 km.
Mass phenomenon - within just 1 hour, millions (!!) of meteors flash in the atmosphere. But, taking into account the brightness of the flashes and the observer’s viewing radius, at night in one hour you can see from several to dozens of meteors (during meteor showers - more than a hundred). Over the course of a day, the mass of dust from meteors deposited on the surface of our planet is calculated in hundreds and even thousands of tons.
Fireballs- the brightest meteors, the brightness of which exceeds the brightness of the planet Venus. The flash may be accompanied by noise effects, including the sound of an explosion. After this, a trail of smoke remains in the sky.
Fragments of cosmic bodies of this size reach the surface of our planet. It happens like this:
At the same time, stone meteoroids, and especially ice ones, are usually crushed into fragments due to explosion and heating. Metal ones can withstand pressure and fall onto the surface entirely:
Iron meteorite "Goba" measuring about 3 meters, which fell "entirely" 80 thousand years ago on the territory of modern Namibia (Africa) If the speed of entry into the atmosphere was very high (oncoming trajectory), then such meteoroids have much less chance of reaching the surface, since the force of their friction with the atmosphere will be much greater. The number of fragments into which a meteoroid is fragmented can reach hundreds of thousands; the process of their fall is called meteor Rain.
Over the course of a day, several dozen small (about 100 grams) fragments of meteorites can fall to Earth in the form of cosmic fallout. Considering that most of them fall into the ocean, and in general, they are difficult to distinguish from ordinary stones, they are found quite rarely.
The number of times a meter-sized cosmic bodies enter our atmosphere is several times a year. If you are lucky and the fall of such a body is noticed, there is a chance to find decent fragments weighing hundreds of grams, or even kilograms.
Supercar- this is what is sometimes called especially powerful meteoroid explosions, like the one that exploded in February 2013 over Chelyabinsk. The initial size of the body that then entered the atmosphere varies according to various expert estimates, on average it is estimated at 17 meters. Weight - about 10,000 tons. 
The object entered the Earth's atmosphere at a very acute angle (15-20°) at a speed of about 20 km/sec. It exploded half a minute later at an altitude of about 20 km. The power of the explosion was several hundred kilotons of TNT. This is 20 times more powerful than the Hiroshima bomb, but here the consequences were not so fatal because the explosion occurred at a high altitude and the energy was dispersed over a large area, largely away from populated areas.
Less than a tenth of the meteoroid's original mass reached Earth, that is, about a ton or less. The fragments were scattered over an area more than 100 km long and about 20 km wide. Many small fragments were found, several weighing kilograms, the largest piece weighing 650 kg was recovered from the bottom of Lake Chebarkul: 
Damage: Almost 5,000 buildings were damaged (mostly broken glass and frames), and about 1.5 thousand people were injured by glass fragments. 
A body of this size could easily reach the surface without breaking into fragments. This did not happen due to the too acute angle of entry, because before exploding, the meteoroid flew several hundred kilometers in the atmosphere. If the Chelyabinsk meteoroid had fallen vertically, then instead of an air shock wave breaking the glass, there would have been a powerful impact on the surface, resulting in a seismic shock, with the formation of a crater with a diameter of 200-300 meters. In this case, judge for yourself about the damage and number of victims; everything would depend on the location of the fall.
Concerning repetition rates similar events, then after the Tunguska meteorite of 1908, this is the largest celestial body to fall to Earth. That is, in one century we can expect one or several such guests from outer space.
The children's toys are over, let's move on to more serious things.
If you read the previous post, then you know that small bodies of the solar system up to 30 meters in size are called meteoroids, more than 30 meters - asteroids.
If an asteroid, even the smallest one, meets the Earth, then it will definitely not fall apart in the atmosphere and its speed will not slow down to the speed of free fall, as happens with meteoroids. All the enormous energy of its movement will be released in the form of an explosion - that is, it will turn into thermal energy, which will melt the asteroid itself, and mechanical, which will create a crater, scatter earthly rock and fragments of the asteroid itself, and also create a seismic wave.
To quantify the scale of such a phenomenon, we can consider, for example, the asteroid crater in Arizona: 
This crater was formed 50 thousand years ago by the impact of an iron asteroid with a diameter of 50-60 meters. The force of the explosion was 8000 Hiroshima, the diameter of the crater was 1.2 km, the depth was 200 meters, the edges rose 40 meters above the surrounding surface.
Another event of comparable scale is the Tunguska meteorite. The power of the explosion was 3000 Hiroshima, but here there was a fall of a small comet nucleus with a diameter of tens to hundreds of meters, according to various estimates. Comet nuclei are often compared to dirty snow cakes, so in this case no crater appeared, the comet exploded in the air and evaporated, felling a forest over an area of 2 thousand square kilometers. If the same comet exploded over the center of modern Moscow, it would destroy all the houses right up to the ring road.
Drop Frequency asteroids tens of meters in size - once every few centuries, hundred-meter ones - once every several thousand years.
Although, according to the latest NASA data, the probability of the Apophis asteroid hitting the Earth during its flight near our planet in 2029 and then in 2036 is practically zero, we will still consider the scenario of the consequences of its possible fall, since there are many asteroids that have not yet been discovered, and such an event can still happen, if not this time, then another time.
The power of the explosion is 15,000 Hiroshima atomic bombs. When it hits the mainland, an impact crater with a diameter of 4-5 km and a depth of 400-500 meters appears, the shock wave demolishes all brick buildings in an area with a radius of 50 km, less durable buildings, as well as trees falling at a distance of 100-150 kilometers from the place falls. A column of dust, similar to a mushroom from a nuclear explosion several kilometers high, rises into the sky, then the dust begins to spread in different directions, and within a few days it spreads evenly across the entire planet. 
But, despite the greatly exaggerated horror stories that the media usually scare people with, nuclear winter and the end of the world will not come - the caliber of Apophis is not enough for this. According to the experience of powerful volcanic eruptions that took place in the not very long history, during which huge emissions of dust and ash also occur into the atmosphere, with such an explosion power the effect of “nuclear winter” will be small - a drop in the average temperature on the planet by 1-2 degrees, after Six months or a year everything returns to its place.
That is, this is a catastrophe not on a global, but on a regional scale - if Apophis gets into a small country, he will destroy it completely.
If Apophis hits the ocean, coastal areas will be affected by the tsunami. The height of the tsunami will depend on the distance to the place of impact - the initial wave will have a height of about 500 meters, but if Apophis falls into the center of the ocean, then 10-20 meter waves will reach the shores, which is also quite a lot, and the storm will last with such mega-waves. there will be waves for several hours. If the impact in the ocean occurs not far from the coast, then surfers in coastal (and not only) cities will be able to ride such a wave: (sorry for the dark humor) 
Recurrence frequency events of similar magnitude in the history of the Earth are measured in tens of thousands of years.
Let's move on to global disasters...
The scenario is the same as during the fall of Apophis, only the scale of the consequences is many times more serious and already reaches a low-threshold global catastrophe (the consequences are felt by all of humanity, but there is no threat of the death of civilization):
The power of the explosion in Hiroshima: 50,000, the size of the resulting crater when falling onto land: 15-20 km. Radius of the destruction zone from blast and seismic waves: up to 1000 km.
When falling into the ocean, again, everything depends on the distance to the shore, since the resulting waves will be very high (1-2 km), but not long, and such waves die out quite quickly. But in any case, the area of flooded territories will be huge - millions of square kilometers.
The decrease in atmospheric transparency in this case from emissions of dust and ash (or water vapor falling into the ocean) will be noticeable for several years. If you enter a seismically dangerous zone, the consequences may be aggravated by earthquakes provoked by an explosion.
However, an asteroid of such diameter will not be able to tilt the Earth’s axis noticeably or affect the rotation period of our planet.
Despite the not-so-dramatic nature of this scenario, this is a fairly ordinary event for the Earth, since it has already happened thousands of times throughout its existence. Average repetition frequency- once every 200-300 thousand years.
But this is not quite Armageddon yet! Our planet has already experienced even such enormous catastrophes dozens or even hundreds of times. On average this happens once once every 100 million years. If this happened at the present time, the number of victims would be unprecedented, in the worst case it could be measured in billions of people, and besides, it is unknown what kind of social upheaval this would lead to. However, despite the period of acid rain and several years of some cooling due to a decrease in the transparency of the atmosphere, in 10 years the climate and biosphere would have been completely restored.
For such a significant event in human history, an asteroid the size of 15-20 kilometers in quantity 1 piece.
The next ice age will come, most of the living organisms will die, but life on the planet will remain, although it will no longer be the same as before. As always, the strongest will survive...
Such events also happened repeatedly in the world. Since the emergence of life on it, Armageddons have happened at least several, and perhaps dozens of times. It is believed that the last time this happened was 65 million years ago ( Chicxulub meteorite), when dinosaurs and almost all other species of living organisms died, only 5% of the chosen ones remained, including our ancestors. 
If a cosmic body the size of the state of Texas crashes into our planet, as it happened in the famous film with Bruce Willis, then even bacteria will not survive (although, who knows?), Life will have to arise and evolve anew. 
I wanted to write a review post about meteorites, but it turned out to be an Armageddon scenario. Therefore, I want to say that all the events described, starting from Apophis (inclusive), are considered theoretically possible, since they will definitely not happen in the next hundred years at least. Why this is so is described in detail in the previous post.
I would also like to add that all the figures given here regarding the correspondence between the size of the meteorite and the consequences of its fall to Earth are very approximate. Data in different sources differ, plus the initial factors during the fall of an asteroid of the same diameter can vary greatly. For example, it is written everywhere that the size of the Chicxulub meteorite is 10 km, but in one, as it seemed to me, authoritative source, I read that a 10-kilometer stone could not have caused such troubles, so for me the Chicxulub meteorite entered the 15-20 kilometer category .
So, if suddenly Apophis still falls in the 29th or 36th year, and the radius of the affected area will be very different from what is written here - write, I’ll correct it
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The previous post assessed the danger of an asteroid threat from space. And here we will consider what will happen if (when) a meteorite of one or another size does fall to Earth.
Meteor shower over Paris
The scenario and consequences of such an event as the fall of a cosmic body to Earth, of course, depends on many factors. Let's list the main ones:
This factor, naturally, is of primary importance. Armageddon on our planet can be caused by a meteorite 20 kilometers in size, so in this post we will consider scenarios for the fall of cosmic bodies on the planet ranging in size from a speck of dust to 15-20 km. More - there is no point, since in this case the scenario will be simple and obvious.
Small bodies of the Solar System can have different compositions and densities. Therefore, there is a difference whether a stone or iron meteorite falls to Earth, or a loose comet core consisting of ice and snow. Accordingly, in order to cause the same destruction, the comet nucleus must be two to three times larger than an asteroid fragment (at the same falling speed).
For reference: more than 90 percent of all meteorites are stone.
Also a very important factor when bodies collide. After all, here the transition of kinetic energy of motion into heat occurs. And the speed at which cosmic bodies enter the atmosphere can vary significantly (from approximately 12 km/s to 73 km/s, for comets - even more).
The slowest meteorites are those that catch up with the Earth or are overtaken by it. Accordingly, those flying towards us will add their speed to the orbital speed of the Earth, pass through the atmosphere much faster, and the explosion from their impact on the surface will be many times more powerful.
At sea or on land. It is difficult to say in which case the destruction will be greater, it will just be different.
A meteorite may fall on a nuclear weapons storage site or a nuclear power plant, then the environmental damage may be greater from radioactive contamination than from the meteorite impact (if it was relatively small).
Doesn't play a big role. At those enormous speeds at which a cosmic body crashes into a planet, it does not matter at what angle it will fall, since in any case the kinetic energy of movement will turn into thermal energy and be released in the form of an explosion. This energy does not depend on the angle of incidence, but only on mass and speed. Therefore, by the way, all craters (on the Moon, for example) have a circular shape, and there are no craters in the form of trenches drilled at an acute angle.
They completely burn up in the atmosphere, leaving a bright trail several tens of kilometers long (a well-known phenomenon called meteor). The largest of them reach altitudes of 40-60 km, but most of these “specks of dust” burn up at altitudes of more than 80 km.
Lyrid meteor shower photo 2009
Mass phenomenon - within just 1 hour, millions (!!) of meteors flash in the atmosphere. But, taking into account the brightness of the flashes and the observer’s viewing radius, at night in one hour you can see from several to dozens of meteors (during meteor showers - more than a hundred). Over the course of a day, the mass of dust from meteors deposited on the surface of our planet is calculated in hundreds and even thousands of tons.
Fireballs- the brightest meteors, the brightness of the flash exceeds the brightness of the planet Venus. The flash may be accompanied by noise effects, including the sound of an explosion. After this, a trail of smoke remains in the sky.
Fragments of cosmic bodies of this size reach the surface of our planet. It happens like this:
Bolide in the atmosphere
At the same time, stone meteoroids, and especially ice ones, are usually crushed into fragments due to explosion and heating. Metal ones can withstand pressure and fall onto the surface entirely:
Iron meteorite "Goba" measuring about 3 meters, which fell "entirely" 80 thousand years ago on the territory of modern Namibia (Africa)
If the speed of entry into the atmosphere was very high (oncoming trajectory), then such meteoroids have much less chance of reaching the surface, since the force of their friction with the atmosphere will be much greater. The number of fragments into which a meteoroid is crushed can reach hundreds of thousands; the process of their falling is called meteor shower.
Over the course of a day, several dozen small (about 100 grams) fragments of meteorites can fall to Earth in the form of cosmic fallout. Considering that most of them fall into the ocean, and in general, they are difficult to distinguish from ordinary stones, they are found quite rarely.
The number of times cosmic bodies about a meter in size enter our atmosphere is several times a year. If you are lucky and the fall of such a body is noticed, there is a chance to find decent fragments weighing hundreds of grams, or even kilograms.
Superbolide is the name sometimes given to particularly powerful meteoroid explosions, like the one that exploded in February 2013 over Chelyabinsk. The initial size of the body that then entered the atmosphere varies according to various expert estimates, on average it is estimated at 17 meters. Weight - about 10,000 tons.
Chebarkul meteorite
The object entered the Earth's atmosphere at a very acute angle (15-20°) at a speed of about 20 km/sec. It exploded half a minute later at an altitude of about 20 km. The power of the explosion was several hundred kilotons of TNT. This is 20 times more powerful than the Hiroshima bomb, but here the consequences were not so fatal because the explosion occurred at a high altitude and the energy was dispersed over a large area, largely away from populated areas.
Less than a tenth of the meteoroid's original mass reached Earth, that is, about a ton or less. The fragments were scattered over an area more than 100 km long and about 20 km wide. Many small fragments were found, several weighing kilograms, the largest piece weighing 650 kg was recovered from the bottom of Lake Chebarkul:
The largest fragment of the Chebarkul (Chelyabinsk) meteorite found, weight 650 kg
Damage: Almost 5,000 buildings were damaged (mostly broken glass and frames), and about 1.5 thousand people were injured by glass fragments.
Broken windows of houses - consequences of a meteorite fall near Chelyabinsk
A body of this size could easily reach the surface without breaking into fragments. This did not happen due to the too acute angle of entry, because before exploding, the meteoroid flew several hundred kilometers in the atmosphere. If the Chelyabinsk meteoroid had fallen vertically, then instead of an air shock wave breaking the glass, there would have been a powerful impact on the surface, resulting in a seismic shock, with the formation of a crater with a diameter of 200-300 meters. In this case, judge for yourself about the damage and number of victims; everything would depend on the location of the fall.
Concerning repetition rates similar events, then after the Tunguska meteorite of 1908, this is the largest celestial body to fall to Earth. That is, in one century we can expect one or several such guests from outer space.
The children's toys are over, let's move on to more serious things.
If you read the previous post, then you know that small bodies of the solar system up to 30 meters in size are called meteoroids, more than 30 meters - asteroids.
If an asteroid, even the smallest one, meets the Earth, then it will definitely not fall apart in the atmosphere and its speed will not slow down to the speed of free fall, as happens with meteoroids. All the enormous energy of its movement will be released in the form of an explosion - that is, it will turn into thermal energy, which will melt the asteroid itself, and mechanical energy, which will create a crater, scatter earthly rock and fragments of the asteroid itself, and also create a seismic wave.
To quantify the scale of such a phenomenon, we can consider, for example, the asteroid crater in Arizona:
This crater was formed 50 thousand years ago by the impact of an iron asteroid with a diameter of 50-60 meters. The force of the explosion was 8000 Hiroshima, the diameter of the crater was 1.2 km, the depth was 200 meters, the edges rose 40 meters above the surrounding surface.
Another comparable event in scale is the Tunguska meteorite. The power of the explosion was 3000 Hiroshima, but here there was a fall of a small comet nucleus with a diameter of tens to hundreds of meters, according to various estimates. Comet nuclei are often compared to dirty snow cakes, so in this case no crater appeared, the comet exploded in the air and evaporated, felling a forest over an area of 2 thousand square kilometers. If the same comet exploded over the center of modern Moscow, it would destroy all the houses right up to the ring road.
Drop Frequency asteroids tens of meters in size - once every few centuries, hundred-meter ones - once every several thousand years.
Although, according to the latest NASA data, the probability of the Apophis asteroid hitting the Earth during its flight near our planet in 2029 and then in 2036 is practically zero, we will still consider the scenario of the consequences of its possible fall, since there are many asteroids that have not yet been discovered, and such an event can still happen, if not this time, then another time.
The power of the explosion is 15,000 Hiroshima atomic bombs. When it hits the mainland, an impact crater with a diameter of 4-5 km and a depth of 400-500 meters appears, the shock wave demolishes all brick buildings in an area with a radius of 50 km, less durable buildings, as well as trees falling at a distance of 100-150 kilometers from the place falls. A column of dust, similar to a mushroom from a nuclear explosion several kilometers high, rises into the sky, then the dust begins to spread in different directions, and within a few days it spreads evenly across the entire planet.
Comparison of destruction zones of the Tunguska meteorite and the Apophis asteroid
But, despite the greatly exaggerated horror stories that the media usually scare people with, nuclear winter and the end of the world will not come - the caliber of “Apophis” is not enough for this. According to the experience of powerful volcanic eruptions that took place in the not very long history, during which huge emissions of dust and ash also occur into the atmosphere, with such an explosion power the effect of “nuclear winter” will be small - a drop in the average temperature on the planet by 1-2 degrees, after Six months or a year everything returns to its place.
That is, this is a catastrophe not on a global, but on a regional scale - if Apophis gets into a small country, he will destroy it completely.
If Apophis hits the ocean, coastal areas will be affected by the tsunami. The height of the tsunami will depend on the distance to the place of impact - the initial wave will have a height of about 500 meters, but if Apophis falls into the center of the ocean, then 10-20 meter waves will reach the shores, which is also quite a lot, and the storm will last with such mega-waves. there will be waves for several hours. If the impact into the ocean occurs not far from the coast, then surfers in coastal (and not only) cities will be able to ride such a wave: :) (sorry for the dark humor)
Tsunami caused by a small asteroid falling into the ocean
Recurrence frequency events of similar magnitude in the history of the Earth are measured in tens of thousands of years.
Let's move on to global disasters...
The scenario is the same as during the fall of Apophis, only the scale of the consequences is many times more serious and already reaches a low-threshold global catastrophe (the consequences are felt by all of humanity, but there is no threat of the death of civilization):
The power of the explosion in Hiroshima: 50,000, the size of the resulting crater when falling onto land: 15-20 km. Radius of the destruction zone from blast and seismic waves: up to 1000 km.
When falling into the ocean, again, everything depends on the distance to the shore, since the resulting waves will be very high (1-2 km), but not long, and such waves die out quite quickly. But in any case, the area of flooded territories will be huge - millions of square kilometers.
The decrease in atmospheric transparency in this case from emissions of dust and ash (or water vapor falling into the ocean) will be noticeable for several years. If you enter a seismically dangerous zone, the consequences may be aggravated by earthquakes provoked by an explosion.
However, an asteroid of such diameter will not be able to tilt the Earth’s axis noticeably or affect the rotation period of our planet.
Despite the not-so-dramatic nature of this scenario, this is a fairly ordinary event for the Earth, since it has already happened thousands of times throughout its existence. Average repetition frequency- once every 200-300 thousand years.
But this is not quite Armageddon yet! Our planet has already experienced even such enormous catastrophes dozens or even hundreds of times. On average this happens once once every 100 million years. If this happened at the present time, the number of victims would be unprecedented, in the worst case it could be measured in billions of people, and besides, it is unknown what kind of social upheaval this would lead to. However, despite the period of acid rain and several years of some cooling due to a decrease in the transparency of the atmosphere, in 10 years the climate and biosphere would have been completely restored.
For such a significant event in the history of mankind, an asteroid 15-20 kilometers in size is required in the amount of 1 piece.
The next ice age will come, most of the living organisms will die, but life on the planet will remain, although it will no longer be the same as before. As always, the strongest will survive...
Such events have also happened many times in the history of the Earth. Since the emergence of life on it, Armageddons have occurred at least several, and perhaps dozens of times. It is believed that the last time this happened was 65 million years ago ( Chicxulub meteorite), when dinosaurs and almost all other species of living organisms died, only 5% of the chosen ones remained, including our ancestors.
Death of dinosaurs from an asteroid impact
If a cosmic body the size of the state of Texas crashes into our planet, as it happened in the famous film with Bruce Willis, then even bacteria will not survive (although, who knows?), Life will have to arise and evolve anew.
Death of the Earth
I wanted to write a review post about meteorites, but it turned out to be an Armageddon scenario. Therefore, I want to say that all the events described, starting from Apophis (inclusive), are considered theoretically possible, since they will definitely not happen in the next hundred years at least. Why this is so is described in detail in the previous post.
I would also like to add that all the figures given here regarding the correspondence between the size of the meteorite and the consequences of its fall to Earth are very approximate. Data in different sources differ, plus the initial factors during the fall of an asteroid of the same diameter can vary greatly. For example, it is written everywhere that the size of the Chicxulub meteorite is 10 km, but in one, as it seemed to me, authoritative source, I read that a 10-kilometer stone could not have caused such troubles, so for me the Chicxulub meteorite entered the 15-20 kilometer category .
So, if suddenly Apophis still falls in the 29th or 36th year, and the radius of the affected area will be very different from what is written here - write, I will correct it.
Consider 10 largest meteorites that fell to Earth: rating of meteorites with photos, descriptions and history of discovery, research, impact force, origin.
From time to time, cosmic bodies fall to Earth... more and less, made of stone or metal. Some of them are no larger than a grain of sand, others weigh several hundred kilograms or even tons. Scientists at the Astrophysical Institute of Ottawa (Canada) claim that several hundred solid alien bodies with a total mass of more than 21 tons visit our planet every year. The weight of most meteorites does not exceed a few grams, but there are also those that weigh several hundred kilograms or even tons.
The places where meteorites fall are either fenced off or, on the contrary, opened for public viewing so that everyone can touch the extraterrestrial “guest”.
Some people confuse comets and meteorites due to the fact that both of these celestial bodies have a fiery shell. In ancient times, people considered comets and meteorites to be a bad omen. People tried to avoid the places where meteorites fell, considering them a cursed zone. Fortunately, in our time, such cases are no longer observed, but on the contrary - the places where meteorites fall are of great interest to the inhabitants of the planet.
In this article we will recall the 10 largest meteorites that fell on our planet.
The meteorite fell on our planet on April 22, 2012, the speed of the fireball was 29 km/sec. Flying over the states of California and Nevada, the meteorite scattered its burning fragments over tens of kilometers and exploded in the sky over the US capital. The power of the explosion is relatively small - 4 kilotons (in TNT equivalent). For comparison, the explosion of the famous Chelyabinsk meteorite had a power of 300 kilotons of TNT.
According to scientists, the Sutter Mill meteorite was formed at the birth of our solar system, a cosmic body more than 4566.57 million years ago.
On February 11, 2012, hundreds of tiny meteorite stones flew over the territory of the People's Republic of China and fell over an area of over 100 km in the southern regions of China. The largest of them weighed about 12.6 kg. According to scientists, the meteorites came from the asteroid belt between Jupiter and Mars.
On September 15, 2007, a meteorite fell near Lake Titicaca (Peru) near the Bolivian border. According to eyewitnesses, the event was preceded by loud noise. Then they saw a body engulfed in fire falling. The meteorite left a bright trail in the sky and a stream of smoke, which was visible several hours after the fireball fell.
A huge crater, 30 meters in diameter and 6 meters deep, formed at the crash site. The meteorite contained toxic substances, as people living nearby began to have headaches.
Stone meteorites (92% of the total) consisting of silicates most often fall to Earth. The Chelyabinsk meteorite is an exception; it was iron.
The meteorite fell on June 20, 1998 near the Turkmen city of Kunya-Urgench, hence its name. Before the fall, local residents saw a bright flash. The largest part of the car weighs 820 kg; this piece fell into a field and formed a 5-meter crater.
According to geologists, the age of this celestial body is about 4 billion years. The Kunya-Urgench meteorite is certified by the International Meteorite Society and is considered the largest of all fireballs that fell in the CIS and third world countries.
The Sterlitamak iron fireball, whose weight was more than 300 kg, fell on May 17, 1990 on a state farm field west of the city of Sterlitamak. When the celestial body fell, a crater of 10 meters was formed.
Initially, small metal fragments were discovered, but a year later scientists managed to extract the largest fragment of the meteorite weighing 315 kg. Currently, the meteorite is in the Museum of Ethnography and Archeology of the Ufa Scientific Center.
This event took place in March 1976 in Jilin province in eastern China. The largest meteor shower lasted more than half an hour. Cosmic bodies fell at a speed of 12 km per second.
Only a few months later, about a hundred meteorites were found, the largest - Jilin (Girin), weighed 1.7 tons.
This meteorite fell on February 12, 1947 in the Far East in the city of Sikhote-Alin. The bolide was crushed in the atmosphere into small iron pieces, which scattered over an area of 15 sq. km.
Several dozen craters with a depth of 1-6 meters and a diameter of 7 to 30 meters were formed. Geologists have collected several tens of tons of meteorite matter.
Goba meteorite (1920)
Meet Goba - one of the largest meteorites found! It fell to Earth 80 thousand years ago, but was found in 1920. A real giant made of iron weighed about 66 tons and had a volume of 9 cubic meters. Who knows what myths the people living at that time associated the fall of this meteorite with.
Composition of the meteorite. This celestial body is 80% iron and is considered the heaviest of all meteorites that have ever fallen on our planet. Scientists took samples, but did not transport the entire meteorite. Today it is located at the crash site. This is one of the largest pieces of iron on Earth of extraterrestrial origin. The meteorite is constantly decreasing: erosion, vandalism and scientific research have taken their toll: the meteorite has decreased by 10%.
A special fence was created around it and now Goba is known throughout the planet, many tourists come to it.
The most famous Russian meteorite. In the summer of 1908, a huge fireball flew over the territory of the Yenisei. The meteorite exploded at an altitude of 10 km above the taiga. The blast wave circled the Earth twice and was recorded by all observatories.
The power of the explosion is simply monstrous and is estimated at 50 megatons. The flight of the space giant is hundreds of kilometers per second. Weight, according to various estimates, varies - from 100 thousand to one million tons!
Fortunately, no one was hurt. A meteorite exploded over the taiga. In nearby settlements, a window was broken by the blast wave.
Trees fell as a result of the explosion. Forest territory of 2,000 sq. turned into rubble. The blast wave killed animals within a radius of more than 40 km. For several days, artifacts were observed over the territory of central Siberia - luminous clouds and a glow in the sky. According to scientists, this was caused by noble gases that were released when the meteorite entered the Earth's atmosphere.
What was it? The meteorite would have left a huge crater at the crash site, at least 500 meters deep. Not a single expedition has been able to find anything like this...
The Tunguska meteor, on the one hand, is a well-studied phenomenon, on the other, one of the biggest mysteries. The celestial body exploded in the air, the pieces burned up in the atmosphere, and there were no remains left on Earth.
The working name “Tunguska meteorite” appeared because this is the simplest and most understandable explanation of the flying burning ball that caused the explosion effect. The Tunguska meteorite has been called a crashed alien ship, a natural anomaly, and a gas explosion. What it was in reality, one can only guess and build hypotheses.
Meteorites have fallen to the ground many times: one fell quite recently - we are talking, of course, about the famous Chelyabinsk meteorite. There are others, no less famous and much larger, the consequences of whose fall were sometimes devastating.
On June 17, 1908, at seven o'clock local time, an air explosion with a power of about 50 megatons occurred in the area of the Podkamennaya Tunguska River - this power corresponds to the explosion of a hydrogen bomb. The explosion and the subsequent blast wave were recorded by observatories all over the world, huge trees on an area of 2000 km² from the supposed epicenter were uprooted, and not a single intact glass was left in the houses of residents. After this, for several more days the sky and clouds in this area glowed, including at night.
Local residents said that shortly before the explosion they saw a huge fireball flying across the sky. Unfortunately, given the year of the incident, not a single photograph of the ball was taken.
None of the numerous research expeditions discovered any celestial body that could serve as a basis for the ball. Moreover, the first expedition arrived in the Tunguska region 19 years after the event described - in 1927.
The event is attributed to the fall of a large meteorite to Earth, which later became known as the Tunguska meteorite, but scientists were unable to detect fragments of the celestial body or at least the matter remaining from its fall. However, in this place an accumulation of microscopic silicate and magnetite balls was recorded, which could not have arisen in this area for natural reasons, so they are attributed to cosmic origin.
It is still unknown exactly what caused the explosion: there is no official hypothesis, but the meteorite nature of the phenomenon still seems most likely.
In December 1922, residents of the Astrakhan province were able to observe a stone falling from the sky: eyewitnesses said that the fireball was enormous in size and made a deafening noise in flight. Afterwards there was an explosion, and from the sky (again according to eyewitnesses) a rain of stones began to fall - the next day, farmers living in that area found fragments of stones of a strange shape and appearance in their fields.
The rumor about the incident quickly spread throughout Russia: expeditions arrived in the Astrakhan province, but for some reason they did not find any traces of the meteorite fall. They were found only 50 years later when plowing the fields of the Leninsky state farm - a total of 82 chondritic meteorites were found, and the fragments were scattered over an area of 25 km2. The largest fragment weighs 284 kg (now it can be seen in the Moscow Fersman Museum), the smallest is only 50 grams, and the composition of the samples clearly indicates their extraterrestrial origin.
The total weight of the found debris is estimated at 1225 kg, while the fall of such a large celestial body did not cause significant damage.
The largest intact meteorite in the world is the Goba meteorite: it is located in Namibia and is a block weighing about 60 tons and a volume of 9 m³, consisting of 84% iron and 16% nickel with a small admixture of cobalt. The surface of the meteorite is iron without any impurities: there is no other single piece of natural iron of such size on Earth.
Only dinosaurs could have observed Goba's fall to Earth: it fell on our planet in prehistoric times and was buried underground for a long time, until in 1920 it was discovered by a local farmer while plowing a field. Now the site has been given the status of a national monument, and anyone can see it for a small fee.
It is believed that when it fell, the meteorite weighed 90 tons, but over the millennia of its stay on the planet, erosion, vandalism and scientific research caused its mass to decrease to 60 tons. Unfortunately, the unique object continues to “lose weight” - many tourists consider it their duty to steal a piece as a souvenir .
On February 12, 1947, a huge block fell in the Ussuri taiga - the event could be observed by residents of the village of Beitsukhe in the Primorsky Territory: as always happens in the case of a meteorite fall, witnesses spoke of a huge fireball, the appearance and explosion of which was followed by a rain of iron fragments, fell over an area of 35 km². The meteorite did not cause significant damage, but it made a number of craters in the ground, one of which was six meters deep.
It is assumed that the mass of the meteorite at the time of entry into the Earth's atmosphere ranged from 60 to 100 tons: the largest of the fragments found weighs 23 tons and is considered one of the ten largest meteorites in the world. There are also several other large blocks formed as a result of the explosion - now the fragments are stored in the Meteorite Collection of the Russian Academy of Sciences and the Khabarovsk Regional Museum named after N. I. Grodekov.
Allende fell to Earth on February 8, 1969 in the Mexican state of Chihuahua - it is considered the largest carbonaceous meteorite on the planet, and at the time of its fall its mass was about five tons.
Today, Allende is the most studied meteorite in the world: its fragments are stored in many museums around the world, and it is notable primarily for the fact that it is the oldest discovered body in the Solar System, the age of which has been accurately determined - it is about 4.567 billion years old.
In addition, a previously unknown mineral, called pangite, was found in its composition for the first time: scientists suggest that such a mineral is part of many space objects, in particular asteroids.
Surprises from space
At 9:20 a.m. on February 15, 2013, residents of the Urals and Kazakhstan witnessed an incredible space show: a bright fireball flashed over their heads and exploded over Chelyabinsk 13 seconds after entering the atmosphere. In the evening of the same day, the “big brother” of the Chelyabinsk meteorite, asteroid 2012 DA14 the size of a 15-story building, flew very close to the Earth. It flew at a distance of 26 thousand kilometers from our planet, so the second show did not happen.
The visit of the space guest did not result in casualties, but about one and a half thousand residents of the city and region suffered from broken windows and panic. Economic damage, according to regional officials, amounted to over a billion rubles.
Shot from DVR/youtube
The Chelyabinsk meteorite was the first whose fall was comprehensively studied and documented. The falling car was filmed on thousands of Chelyabinsk residents' car recorders, and a whole team of geologists led by Viktor Grokhovsky, who caught the Chelyabinsk from the bottom of Lake Chebarkul in October 2013, hunted for its remains.
The fall of Chelyabinsk, the largest object to collide with the Earth since the Tunguska meteorite, shook the public, politicians and the scientific community. Network users began to watch disaster films about asteroids and comets, and politicians were surprised to discover that the Earth is not in empty space, but surrounded by thousands of huge objects that threaten to destroy a large part of the planet.
The site of the fall of the Tunguska meteorite. Traces of a forest fire and forest fall
A direct result of the Chelyabinsk meteorite fall was a tripling of NASA's budget for monitoring and combating near-Earth objects. Russian officials have announced their readiness to create a system that would shoot down visitors from space using thermonuclear warheads, and promised to develop an early warning program under the auspices of the Ministry of Emergency Situations by 2020.
On both sides of the ocean, people had the same questions: why was the Chelyabinsk not discovered before it fell? How is it possible and is it possible in principle to combat such a cosmic threat? What do the falling celestial stones threaten us with and how much does it cost to protect ourselves from them?
Space Population Census
The answer to the question why the meteorite was not discovered in time is quite simple: small celestial bodies with a diameter of about 20 meters, like Chelyabinsk, are not considered by asteroid hazard experts to be capable of causing serious harm to the Earth and therefore do not closely monitor them.
Although scientists still keep an eye on such celestial stones with the help of robotic telescopes as part of the Catalina Sky Survey, Pan-STARRS and many other public and private initiatives. But the main “responsible” for the search for potential killers of humanity is the orbital infrared telescope WISE, which finds even asteroids invisible from Earth, which almost do not reflect light.
WISE telescope, photo: NASA
Based on the results of the work of the telescope, NASA in 2010 and 2011 published a catalog of near-Earth objects - about 18.5 thousand in total, and also used the danger criteria developed at the Massachusetts Institute of Technology (Turin scale), according to which all asteroids in the NEOWISE catalog were colored according to the probability of their collision with the Earth from white (no danger) to red (collision imminent).
Good news: as of today, all objects in this catalog are white. This means that so far scientists have not been able to find a single near-Earth asteroid whose probability of falling to Earth in the next 200 years exceeds 1%, or three on the Turin scale. Periodically, objects with non-zero danger scores appeared in the catalog, but as their orbits were refined, they quickly dropped first to one, and then to zero.
Two asteroids - Apophis and Bennu - were assigned very high hazard index values when they were discovered. Opened in 2004, the 350-meter Apophis (by the way, it was named not in honor of the ancient Egyptian god Apep, but in honor of the villain from the TV series Stargate: SG-1) first received a record two at that time, and then a four on the Turin scale. The collision with Earth was supposed to occur in 2036.
A photograph of the Itokawa asteroid taken during the Japanese Hayabusa mission in 2005. Presumably, the asteroid is identical in composition and size to Apophis. Photo: ISAS/JAXA
Two years later, when astronomers refined the asteroid’s orbit, it was lowered first to one and then to zero. The probability that Apophis will meet Earth is estimated at 0.00089%, or one chance in 112 thousand. Today, the most dangerous near-Earth object is considered to be the 500-meter Apollo asteroid 2009 FD, which may fall to Earth in 2185 with a probability of 0.29%.
Orbit of Apophis
As for objects the size of Chelyabinsk, scientists cannot estimate how often they can fall to Earth and whether the real threat is great. In 2011, at the first presentation of the NEOWISE catalog, NASA reported that today we know only about five thousand asteroids about one hundred meters in size, while their total number is estimated at several tens of thousands. The number of smaller objects within the main asteroid belt may reach a million.
Made from something
It is impossible to accurately assess the damage due to the fact that we know very little about the composition of asteroids, and this is critical information, without which it is impossible to assess the consequences of the fall of a hypothetical “Apophis” to Earth.
The idea of studying asteroids “in situ” has been in the minds of astronomers for quite some time. The pioneer in this matter was the Japanese Hayabusa probe, which went to the Itokawa asteroid in 2008 in order to collect soil samples. Due to numerous breakdowns and fantastic bad luck, the Hayabusa managed to collect only one and a half thousand dust particles, which it nevertheless delivered to Earth in 2010.
Hayabusa-2. Image: JAXA
In the winter of 2014, the successor of the unsuccessful probe, the Hayabusa-2 apparatus, set off for the asteroid 1999 JU3, which will arrive at the target in 2018. In parallel, NASA is developing its own mission, OSIRIS-REx, which will fly to Bennu in 2016 with the same mission as Hayabusa.
The lack of specific data on the composition of asteroids does not prevent engineers from dreaming of defense systems against celestial guests. One of the many projects is the DE-STAR system, which should properly heat a dangerous asteroid and knock it off its path. According to the calculations of the authors of the idea, a platform 100 meters in size will be enough to push Apophis out of its orbit, and a ten-kilometer laser will be enough to completely evaporate it.
In addition, there are projects like the NEOShield or ISIS probes, a potential “companion” of OSIRIS-REx, which involve diverting asteroids from their intended course with a “right hook” - a collision with a heavy metal blank. As an option, engineers propose attaching a heavy satellite to the stone, which will change the orbit of the celestial body. Russian scientists from the Institute of Space Research are planning to shoot down asteroids with the help of other asteroids.
Artist's rendering of OSIRIS-REx. Image: University of Arizona/Goddard/NASA
Until Hayabusa2 and OSIRIS-REx reach their targets, scientists can only guess at the exact mineral and chemical composition of the asteroids. The composition of celestial bodies can be determined from their spectra, but due to collisions with other bodies, the surface of asteroids can radically change color, so the spectrum will deceive astronomers. Without knowing the composition, one can only approximately estimate the consequences of the fall of space rocks, based on what disasters the Earth has already experienced in the past.
Well forgotten old
The most famous and studied trace of such falls is the Chicxulub crater on the Yucatan Peninsula in southern Mexico. The fall of a 10-kilometer cosmic “boulder” 65.5 million years ago left a crater with a diameter of 180 kilometers and led to catastrophic consequences: it is believed that it was because of the fall of the meteorite that dinosaurs and a fair part of the Mesozoic fauna became extinct.
And this is not the worst option: the diameter of the Vredefort crater in South Africa, apparently left by a meteorite, is 300 kilometers. The “pebble” fell to Earth about two billion years ago, when microbes dominated the planet. Just recently, scientists discovered in Australia an as yet unnamed crater with a diameter of 400 kilometers, which arose about 300-420 million years ago.
Another thing is that not many traces of encounters with small asteroids - up to several hundred meters - are known, so the consequences of the fall of such stones on cities and densely populated countries cannot be determined.
One of the few examples of such events is the so-called “Clovis Comet” - an object supposedly the size of the Tunguska meteorite (scientists do not agree whether it was an asteroid or a comet), which fell into the New World approximately 13 thousand years ago. Its fall caused large-scale fires, a sharp cooling due to clouds of ash and aerosol particles, the extinction of the remains of megafauna and the disappearance of the Clovis culture, the first tribes of the American Indians.
Only in 2013 did geologists manage to localize the crash site of this object: it crashed in the province of Quebec in Canada, but the crater itself has not yet been found. So it may very well be that the Clovis Comet was relatively small.
What to do?
This question is regularly asked to the head of NASA and Russian space officials. As the current head of the American Space Agency put it, so far humanity has only one option - “pray”, since the problem has been ignored for decades and there are no effective means for destruction and 100% detection of asteroids.
Moreover, until the results of the Hayabusa and Osiris studies are received, as well as complete catalogs of near-Earth asteroids, governments are unlikely to allocate money for anything other than prayer. Politicians remember celestial surprises only when the next Chelyabinsk falls, and their ardor quickly cools when they see calculations of the amounts that need to be invested in protecting the Earth. So today humanity can only hope for commercial projects for the “development” of asteroids - perhaps the data they collect on small celestial bodies and comets will convince officials to seriously think about the future of the planet.
Alexander Telishev
