The speed of a meteorite in space. The consequences of meteorites of various diameters falling to the ground. Our time and new facts about fallen meteorites

We have been prophesied many times about the End of the World according to the scenario that would hit Earth a meteorite will fall, an asteroid and will blow everything to smithereens. But it did not fall, although small meteorites fell.

Could a meteorite still fall on Earth and destroy all life? What asteroids have already fallen on Earth and what consequences did this entail? Today we’ll talk about this.

By the way, the next End of the World is predicted for us in October 2017!!

Let's first understand what a meteorite, meteoroid, asteroid, comet is, at what speed they can hit the Earth, for what reason the trajectory of their fall is directed to the surface of the Earth, what destructive power meteorites carry, taking into account the speed of the object and mass.

Meteroid

“A meteoroid is a celestial body intermediate in size between cosmic dust and an asteroid.

A meteoroid flying into the Earth's atmosphere at great speed (11-72 km/s) becomes very hot due to friction and burns, turning into a luminous meteor (which can be seen as a “shooting star”) or a fireball. The visible trace of a meteoroid entering the Earth's atmosphere is called a meteor, and a meteoroid falling on the Earth's surface is called a meteorite."

Cosmic dust- small celestial bodies that burn in the atmosphere and are initially small in size.

Asteroid

“Asteroid (a synonym common until 2006 - minor planet) is a relatively small celestial body solar system, moving in orbit around the Sun. Asteroids are significantly smaller in mass and size than planets and have Not correct form and do not have an atmosphere, although they may also have satellites.”

Comet

“Comets are like asteroids, but they are not lumps, but frozen floating swamps. They mostly live at the edge of the solar system, forming the so-called Oort cloud, but some fly to the Sun. As they approach the Sun, they begin to melt and evaporate, forming behind them a beautiful tail glowing in the sun's rays. Among superstitious people they are considered harbingers of misfortune.”

Bolide- a bright meteor.

Meteor — “(Ancient Greek μετέωρος, “heavenly”), “shooting star” is a phenomenon that occurs when small meteoroids (for example, fragments of comets or asteroids) burn up in the Earth’s atmosphere.”

And finally, the meteorite:"Meteor - body cosmic origin, fallen onto the surface of a large celestial object.

Most meteorites found have a mass from a few grams to several kilograms (the largest meteorite found is Goba, which was estimated to weigh about 60 tons). It is believed that 5-6 tons of meteorites fall to the Earth per day, or 2 thousand tons per year.”

All relatively large celestial bodies that enter the Earth's atmosphere burn up before reaching the surface, and those that reach the surface are called meteorites.

Now think about the numbers: “5-6 tons of meteorites fall on the Earth per day, or 2 thousand tons per year”!!! Imagine, 5-6 tons, but we rarely hear reports that someone was killed by a meteorite, why?

Firstly, small meteorites fall, such that we don’t even notice, many fall on uninhabited lands, and secondly: cases of death from a meteorite strike are not excluded, type in a search engine, in addition, meteorites have repeatedly fallen near people, on dwellings (Tunguska bolide, Chelyabinsk meteorite, meteorite falling on people in India).

Every day over 4 billion cosmic bodies fall to Earth, that's what they call everything that's bigger cosmic dust and smaller than an asteroid, say sources of information about the life of the Cosmos. Basically, these are small stones that burn up in the layers of the atmosphere before reaching the earth's surface; a few pass this line; they are called meteorites, whose total weight per day is several tons. Meteoroids that do reach Earth are called meteorites.

A meteorite falls to Earth at a speed of 11 to 72 km per second; during the process of enormous speed, the celestial body heats up and glows, which causes part of the meteorite to “blow”, reducing its mass, sometimes dissolving, especially at a speed of about 25 km per second or more . When approaching the surface of the planet, the surviving celestial bodies slow down their trajectory, falling vertically, and as a rule they cool down, which is why there are no hot asteroids. If a meteorite breaks apart along the “road,” a so-called meteor shower can occur, when many small particles fall to the ground.

At a low speed of the meteorite, for example a few hundred meters per second, the meteorite is able to retain the same mass. Meteorites are stony (chondrites (carbonaceous chondrites, ordinary chondrites, enstatite chondrites)

achondrites), iron (siderites) and iron-stone (pallasites, mesosiderites).

“The most common meteorites are stony meteorites (92.8% of falls).

The vast majority of stony meteorites (92.3% stony, 85.7% total number falls) - chondrites. They are called chondrites because they contain chondrules - spherical or elliptical formations of predominantly silicate composition.”

Chondrites in the photo

Mostly meteorites are about 1 mm, maybe a little more... In general, smaller than a bullet... Perhaps there are a lot of them under our feet, perhaps they fell right before our eyes once, but we did not notice it.

So, what happens if a large meteorite falls to the Earth, does not crumble into a rain of stones, and does not dissolve in the layers of the atmosphere?

How often does this happen and what are the consequences?

Fallen meteorites were discovered by finds or by falls.

For example, according to official statistics, the following number of meteorite falls was recorded:

in 1950-59 - 61, on average 6.1 meteorite falls per year,

in 1960-69 - 66, on average 6.6 per year,

in 1970-79 - 61, average per year 6.1,

in 1980-89 - 57, average per year 5.7,

in 1990-99 - 60, on average 6.0 per year,

in 2000-09 - 72, average per year 7.2,

in 2010-16 - 48, on average 6.8 per year.

As we can see even according to official data, the number of meteorite falls is increasing recent years, decades. But, naturally, we don’t mean 1mm-thick celestial bodies...

Meteorites weighing from several grams to several kilograms fell to Earth in countless quantities. But there were not so many meteorites weighing more than a ton:

The Sikhote-Alin meteorite weighing 23 tons fell to the ground on February 12, 1947 in Russia, in the Primorsky Territory (classification - Zhelezny, IIAB),

Girin - a meteorite weighing 4 tons fell to the ground on March 8, 1976 in China, in the province of Girin (classification - H5 No. 59, chondrite),

Allende - a meteorite weighing 2 tons fell to the ground on February 8, 1969 in Mexico, Chihuahua (classification CV3, chondrite),

Kunya-Urgench - a meteorite weighing 1.1 tons fell to the ground on June 20, 1998 in Turkmenistan, in the city in the North-East of Turkmenistan - Tashauz (classification - chondrite, H5 No. 83),

Norton County - a meteorite weighing 1.1 tons fell to the ground on February 18, 1948 in the USA, Kansas (Aubrit classification),

Chelyabinsk - a meteorite weighing 1 ton fell to the ground on February 15, 2013 in Russia, in the Chelyabinsk region (chondrite classification, LL5 No. 102†).

Of course, the closest and most understandable meteorite to us is the Chelyabinsk meteorite. What happened when the meteorite fell? A series of shock waves during the destruction of a meteorite above Chelyabinsk region and Kazakhstan, the largest of the fragments, weighing about 654 kg, was recovered from the bottom of Lake Chebarkul in October 2016.

On February 15, 2013, at approximately 9:20 a.m., fragments of a small asteroid collided with the earth’s surface, which collapsed as a result of braking in the Earth’s atmosphere; the largest fragment weighed 654 kg; it fell into Lake Chebarkul. The superbolide collapsed in the vicinity of Chelyabinsk at an altitude of 15-25 km, the bright glow from the burning of the asteroid in the atmosphere was noticed by many residents of the city, someone even decided that the plane had crashed or a bomb had fallen, this was the main version of the media in the first hours. The largest meteorite known after the Tunguska meteorite. The amount of released energy, according to experts, ranged from 100 to 44 kilotons of TNT equivalent.

According to official data, 1,613 people were injured, mainly from broken glass from houses damaged by the explosion, about 100 people were hospitalized, two ended up in intensive care, the total amount of damage caused to buildings was about 1 billion rubles.

The Chelyabinsk meteoroid, according to NASA's preliminary estimates, was 15 meters in size and weighed 7,000 tons - these are its data before entering the Earth's atmosphere.

Important factors for assessing the potential danger of meteorites to the earth are the speed with which they approach the earth, their mass, and composition. On the one hand, the speed can destroy the asteroid into small fragments even before the earth’s atmosphere, on the other hand, it can give a powerful blow if the meteorite still reaches the ground. If an asteroid flies with less force, the probability of its mass being preserved is greater, but the force of its impact will not be so terrible. It is the combination of factors that is dangerous: the conservation of mass at the highest speed of the meteorite.

For example, a meteorite weighing more than a hundred tons hitting the ground at the speed of light can cause irreparable destruction.

Information from the documentary.

If you launch a round diamond ball with a diameter of 30 meters towards the Earth at a speed of 3 thousand km per second, then the air will begin to participate in nuclear fusion and, under the heating of the plasma, this process can destroy the diamond sphere even before it reaches the surface of the Earth: information from scientific films, according to scientists' projects. However, the chances that the diamond ball, even if broken, will reach the Earth are great; during the impact, it will release a thousand times more energy than from the most powerful nuclear weapons, and after that the area in the area of ​​the fall will be empty, the crater will be large, but the Earth has seen more. This is at 0.01 from speed of light.

What will happen if you accelerate the sphere to 0.99% of the speed of light? Superatomic energy will begin to operate, the diamond ball will become just a collection of carbon atoms, the sphere will flatten into a pancake, each atom in the ball will carry 70 billion volts of energy, it passes through the air, air molecules pierce through the center of the ball, then get stuck inside, it expands and reaches the Earth with a greater content of matter than at the beginning of the journey, when it crashes into the surface, it will pierce the Earth crooked and wide, creating a cone-shaped road through the root rock. The energy of the collision will tear a hole in the Earth's crust and explode into a crater so large that the molten mantle can be seen through it, an impact comparable to the 50 impacts of the Chicxulub asteroid, which killed the dinosaurs in the era BC. It is quite possible the end of all life on Earth, or at least the extinction of all people.

What will happen if we add more speed to our diamond sphere? Up to 0.9999999% of the speed of light? Now each carbon molecule carries 25 trillion wills of energy (!!!), which is comparable to the particles inside the large hadron collider, all of this will hit our planet with approximately the kinetic energy of the Moon moving in orbit, this is enough to punch a huge hole in the mantle and shake earth's surface planet so that it simply melts, this with a 99.99% probability will put an end to all life on Earth.

Let's add more speed to the diamond ball up to 0.99999999999999999999951% of the speed of light, This is the highest speed of an object with mass ever recorded by man. Particle “Oh my God!”

The Oh-My-God particle is a cosmic shower caused by ultra-high energy cosmic rays, discovered on the evening of October 15, 1991 at the Dugway Proving Grounds in Utah using a detector cosmic rays"Eye of the Fly" (English) owned by the University of Utah. The energy of the particle that caused the shower was estimated to be 3 × 1020 eV (3 × 108 TeV), about 20 million times greater than the energy of particles emitted by extragalactic objects, in other words, the atomic nucleus had a kinetic energy equivalent to 48 joules.

This is the energy of a 142-gram baseball moving at a speed of 93.6 kilometers per hour.

The Oh-My-God particle had such high kinetic energy that it moved through space at approximately 99.99999999999999999999951% of the speed of light."

This proton from Space, which “lit up” the atmosphere over Utah in 1991 and moved almost at the speed of light, the cascade of particles that were formed from its movement could not be reproduced even by the LHC (collider), such phenomena are detected several times a year and no one doesn't understand what it is. It seems to be coming from a galaxy-wide explosion, but what happened to cause these particles to come to Earth in such a hurry and why they did not slow down remains a mystery.

And if the diamond ball moves at the speed of the “Oh, my God!” particle, then nothing will help and no computer technology will simulate the development of events in advance; this plot is a godsend for dreamers and blockbuster creators.

But the picture will look something like this: a diamond ball rushes through the atmosphere, not noticing it and disappearing into the earth's crust, a cloud of expanding plasma with radiation diverges from the entry point, while energy pulsates outward through the body of the planet, as a result the planet becomes heated, begins to glow, the Earth will be knocked out into another orbit Naturally, all living things will die.

Taking into account the picture of the fall of the Chelyabinsk meteorite, which we recently observed, the scenarios of the fall of meteorites (diamond balls) from the film presented in the article, the plots of science fiction films - we can assume that:

- the fall of a meteorite, despite all the assurances of scientists that it is realistic to predict the fall of a large celestial body to Earth in decades, taking into account the achievements in the field of astronautics, cosmonautics, astronomy - in some cases it is impossible to predict!! And the proof of this Chelyabinsk meteorite, which no one predicted. And the proof of this is the particle “Oh, my God!” with their protons over Utah in '91... As they say, we don’t know what hour or day the end will come. However, humanity has been living and living for several thousand years now...

- first of all, we should expect small meteorites, and the destruction will be similar to that of the Chelyabinsk meteorite: glass will burst, buildings will be destroyed, perhaps part of the area will be scorched...

One should hardly expect terrible consequences as with the supposed death of dinosaurs, but cannot exclude them either.

- it is impossible to protect yourself from the forces of Space, unfortunately, meteorites make it clear to us that we are only small people on a small planet in a vast Universe, therefore it is impossible to predict the outcome, the time of contact of an asteroid with the earth, piercing the atmosphere more and more actively every year, Space seems to be claiming to our territory. Get ready or don’t get ready, but if the forces of heaven send an asteroid to our Earth, there’s no corner you can hide in…. So meteorites are also sources of deep philosophy and rethinking of life.

And here's another news!! We have just recently been prophesied about another End of the World!!! October 12, 2017, that is, we have very little time left. Presumably. A huge asteroid is rushing towards Earth!! This information is all over the news, but we are so used to such cries that we don’t react... what if...

According to scientists, the Earth already has holes and cracks, it is burning at the seams... If an asteroid reaches it, and a huge one, as predicted, it simply will not survive. You can only be saved by being in a bunker.

We'll wait and see.

There are opinions of psychologists that such intimidation is an attempt by any means to instill fear in humanity and control it in this way. The asteroid is indeed planning to pass by the Earth soon, but it will pass very far, there is a one in a million chance that it will hit the Earth.

However, in space everything is different, some phenomena are simply inexplicable and cannot be subject to any laws in principle. For example, a satellite launched several years ago, or other objects will rotate in their orbit and will never fall. Why is this happening? At what speed does a rocket fly into space?? Physicists suggest that there is a centrifugal force that neutralizes the effect of gravity.

Having done a small experiment, we can understand and feel this ourselves, without leaving home. To do this, you need to take a thread and tie a small weight to one end, then unwind the thread in a circle. We will feel that the higher the speed, the clearer the trajectory of the load, and the more tension the thread will have; if we weaken the force, the speed of rotation of the object will decrease and the risk that the load will fall increases several times. With this little experience we will begin to develop our topic - speed in space.

It becomes clear that high speed allows any object to overcome the force of gravity. As for space objects, they each have their own speed, it is different. There are four main types of such speed and the smallest of them is the first. It is at this speed that the ship flies into Earth orbit.

In order to fly beyond its limits you need a second speed in space. At the third speed, gravity is completely overcome and you can fly out of the solar system. Fourth rocket speed in space will allow you to leave the galaxy itself, this is approximately 550 km/s. We have always been interested rocket speed in space km h, when entering orbit it is equal to 8 km/s, beyond it - 11 km/s, that is, developing its capabilities to 33,000 km/h. The rocket gradually increases speed, full acceleration begins from an altitude of 35 km. Speedspacewalk is 40,000 km/h.

Speed ​​in space: record

Maximum speed in space- the record, set 46 years ago, still stands, it was achieved by astronauts who took part in the Apollo 10 mission. Having flown around the Moon, they returned back when speed spaceship in space was 39,897 km/h. In the near future, it is planned to send the Orion spacecraft into zero-gravity space, which will launch astronauts into low Earth orbit. Perhaps then it will be possible to break the 46-year-old record. Speed ​​of light in space- 1 billion km/h. I wonder if we can cover such a distance with our maximum available speed of 40,000 km/h. Here what is the speed in space develops in the light, but we don’t feel it here.

Theoretically, a person can move at a speed slightly less than the speed of light. However, this will entail colossal harm, especially for an unprepared organism. After all, first you need to develop such a speed, make an effort to safely reduce it. Because rapid acceleration and deceleration can be fatal to a person.

In ancient times, it was believed that the Earth was motionless; no one was interested in the question of the speed of its rotation in orbit, because such concepts did not exist in principle. But even now it is difficult to give an unambiguous answer to the question, because the value is not the same in different geographical locations. Closer to the equator, the speed will be higher; in the region of southern Europe it is 1200 km/h, this is the average Earth's speed in space.

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:

Size of cosmic body

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.

Compound

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, to cause the same destruction, the comet's 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.

Speed

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 orbital speed The Earth will pass through the atmosphere much faster, and the explosion from their impact on the surface will be many times more powerful.

Where will it fall

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, causing harm to environment may be more from radioactive contamination than from a meteorite impact (if it was relatively small).

Angle of incidence

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.

How do bodies of different diameters behave when falling to Earth?

Up to several centimeters

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.

From centimeters to several meters

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 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 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.

17 meters - Chelyabinsk bolide

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.

Regarding 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.

Tens of meters - small asteroids

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 a small comet nucleus with a diameter of tens to hundreds of meters fell different 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.

300 meters - asteroid Apophis (the most dangerous known at the moment)

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.

So... the asteroid Apophis, contrary to all forecasts, falls to Earth...

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 mushroom-like column of dust rises into the sky from nuclear explosion several kilometers high, 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 of a global, but of a regional scale - if Apophis falls into 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)

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...

1 kilometer

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 not all the drama 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.

An asteroid with a diameter of 10 kilometers is a global catastrophe on a planetary scale

• Hiroshima explosion power: 50 million
• The size of the resulting crater when it falls on land: 70-100 km, depth - 5-6 km.
• Crack depth earth's crust will be tens of kilometers, that is, right up to the mantle (the thickness of the earth's crust under the plains is on average 35 km). Magma will begin to emerge to the surface.
• The area of ​​the destruction zone can be several percent of the Earth's area.
• During the explosion, a cloud of dust and molten rock will rise to a height of tens of kilometers, possibly up to hundreds. The volume of ejected materials is several thousand cubic kilometers - this is enough for a light “asteroid autumn”, but not enough for an “asteroid winter” and the beginning of an ice age.
• Secondary craters and tsunamis from fragments and large pieces of ejected rock.
• A small, but by geological standards, decent tilt of the earth’s axis from the impact - up to 1/10 of a degree.
• When it hits the ocean, it results in a tsunami with kilometer-long (!!) waves that go far into the continents.
• In the event of intense eruptions of volcanic gases, acid rain is subsequently possible.

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 atmospheric transparency, in 10 years the climate and biosphere would have been completely restored.

Armageddon

For such a significant event in human history, an asteroid the size of 15-20 kilometers in quantity 1 piece.

Another one will come ice age, most 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 last time this happened 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.

Full Armageddon

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.

Conclusion

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

The most well studied among the small bodies of the Solar System are asteroids - small planets. The history of their study goes back almost two centuries. Back in 1766, an empirical law was formulated that determined the average distance of a planet from the Sun depending on the serial number of this planet. In honor of the astronomers who formulated this law, it was named: “Titius-Bode law”. a = 0.3*2k + 0.4 where the number k = -* for Mercury, k = 0 for Venus, then k = n - 2 for Earth and Mars, k = n - 1 for Jupiter, Saturn and Uranus (n is the serial number of the planet from the Sun).

At first, astronomers, preserving the traditions of the ancients, assigned small planets the names of gods, both Greco-Roman and others. By the beginning of the twentieth century, the names of almost all gods known to mankind appeared in the sky - Greco-Roman, Slavic, Chinese, Scandinavian and even the gods of the Mayan people. Discoveries continued, there were not enough gods, and then the names of countries, cities, rivers and seas, the names and surnames of real living or living people began to appear in the sky. The question of streamlining the procedure for this astronomical canonization of names became inevitable. This question is all the more serious because, unlike the perpetuation of memory on Earth (names of streets, cities, etc.), the name of an asteroid cannot be changed. The International Astronomical Union (IAU) has been doing this since its creation (July 25, 1919).

The semimajor axes of the orbits of the main part of the asteroids range from 2.06 to 4.09 AU. e., and the average value is 2.77 a. e. The average eccentricity of the orbits of minor planets is 0.14, the average inclination of the asteroid’s orbital plane to the Earth’s orbital plane is 9.5 degrees. The speed of movement of asteroids around the Sun is about 20 km/s, the period of revolution (asteroid year) is from 3 to 9 years. The period of asteroids' own rotation (i.e., the length of a day on an asteroid) averages 7 hours.

Generally speaking, no main belt asteroid passes close to the Earth's orbit. However, in 1932, the first asteroid was discovered whose orbit had a perihelion distance less than the radius of the Earth's orbit. In principle, its orbit allowed for the possibility of the asteroid approaching the Earth. This asteroid was soon "lost" and rediscovered in 1973. It was numbered 1862 and named Apollo. In 1936, the asteroid Adonis flew at a distance of 2 million km from the Earth, and in 1937, the asteroid Hermes flew at a distance of 750 thousand km from the Earth. Hermes has a diameter of almost 1.5 km, and was discovered only 3 months before its closest approach to the Earth. After Hermes' flyby, astronomers began to recognize a scientific problem asteroid danger. To date, about 2,000 asteroids are known whose orbits allow them to approach Earth. Such asteroids are called near-Earth asteroids.

According to their physical characteristics, asteroids are divided into several groups, within which the objects have similar reflective surface properties. Such groups are called taxonomic (taxometric) classes or types. The table shows the 8 main main taxonomic types: C, S, M, E, R, Q, V and A. Each class of asteroids corresponds to meteorites that have similar optical properties. Therefore, each taxometric class can be characterized by analogy with the mineralogical composition of the corresponding meteorites.

The shape and size of these asteroids are determined using radar as they pass near the Earth. Some of them are similar to main belt asteroids, but most of them have a less regular shape. For example, the asteroid Toutatis consists of two, and maybe more, bodies in contact with each other.

Based on regular observations and calculations of asteroid orbits, the following conclusion can be drawn: there are so far no known asteroids that can be said to come close to Earth in the next hundred years. The closest will be the passage of the asteroid Hathor in 2086 at a distance of 883 thousand km.

To date, a number of asteroids have passed at distances significantly smaller than those given above. They were discovered during their closest passages. Thus, for now, the main danger is from yet undiscovered asteroids.

The speed of a meteorite body that falls to Earth, flying from the distant depths of space, exceeds the second cosmic speed, whose value is eleven point two kilometers per second. This meteorite speed equal to the one that needs to be given spacecraft to break out of gravitational field, that is, this speed is acquired by the body due to the gravity of the planet. However, this is not the limit. Our planet moves in orbit at a speed of thirty kilometers per second. When a moving object of the Solar System crosses it, it can have a speed of up to forty-two kilometers per second, and if a celestial wanderer moves along an oncoming trajectory, that is, head-on, then it can collide with the Earth at a speed of up to seventy-two kilometers per second . When a meteorite body enters the upper layers of the atmosphere, it interacts with rarefied air, which does not greatly interfere with the flight, creating almost no resistance. In this place, the distance between the gas molecules is greater than the size of the meteorite itself and they do not interfere with the flight speed, even if the body is quite massive. In the same case, if the mass of a flying body is even slightly greater than the mass of a molecule, then it slows down already in the uppermost layers of the atmosphere and begins to settle under the influence of gravity. This is how about a hundred tons of cosmic matter settle on Earth in the form of dust, and only one percent of large bodies still reach the surface.

So, at an altitude of one hundred kilometers, a freely flying object begins to slow down under the influence of friction arising in the dense layers of the atmosphere. A flying object encounters strong air resistance. The Mach number (M) characterizes the movement solid V gas environment and is measured by the ratio of the speed of the body to the speed of sound in the gas. This M number for a meteorite constantly changes with altitude, but most often does not exceed fifty. A rapidly flying body forms an air cushion in front of it, and the compressed air leads to the appearance of a shock wave. Compressed and heated gas in the atmosphere heats up to very high temperature and the surface of the meteorite begins to boil and splash, carrying away the molten and remaining solid material, that is, the process of abelation occurs. These particles glow brightly, and the phenomenon of a fireball occurs, leaving a bright trail behind it. The compression area that appears in front of a meteorite rushing at enormous speed diverges to the sides and at the same time a head wave is formed, similar to that which occurs from a ship walking on the lead. The resulting cone-shaped space forms a wave of vortex and rarefaction. All this leads to a loss of energy and causes increased deceleration of the body in the lower layers of the atmosphere.

It may happen that the speed of a is from eleven to twenty-two kilometers per second, its mass is not large, and it is mechanically strong enough, then it can slow down in the atmosphere. This ensures that such a body is not subject to abelation; it can reach the surface of the Earth almost unchanged.

As you descend further, the air slows down more and more. meteorite speed and at an altitude of ten to twenty kilometers from the surface it completely loses cosmic speed. The body seems to hang in the air, and this part of the long journey is called the delay region. The object gradually begins to cool down and stops glowing. Then everything that remains from the difficult flight falls vertically to the surface of the Earth under the force of gravity at a speed of fifty to one hundred and fifty meters per second. In this case, the force of gravity is compared with air resistance, and the heavenly messenger falls like an ordinary thrown stone. It is this meteorite speed that characterizes all objects that have fallen to Earth. At the impact site, as a rule, depressions of different sizes and shapes are formed, which depends on the weight of the meteorite and the speed with which it approached the soil surface. Therefore, by studying the crash site, we can say exactly what the approximate meteorite speed at the moment of collision with the Earth. A monstrous aerodynamic load gives the celestial bodies that come to us characteristic features, by which they can be easily distinguished from ordinary stones. They form a melting crust, the shape is most often cone-shaped or melted-clastic, and the surface, as a result of high-temperature atmospheric erosion, receives a unique rhemgalyptian relief.