What does apothesis look like? Asteroid 'Apophis' - Consequences of a possible fall. Possible consequences of the failed collision of Apophis

Friday, April 13, 2029 This day threatens to be fatal for the entire planet Earth. At 4:36 GMT, the asteroid Apophis 99942 with a mass of 50 million tons and a diameter of 320 m will cross the orbit of the Moon and rush towards the Earth at a speed of 45,000 km/h. A huge, pockmarked block will contain the energy of 65,000 Hiroshima bombs - this is more than enough to wipe out a small country from the face of the Earth or shake a tsunami a couple of hundred meters high.
The name of this asteroid speaks for itself - that was the name of the ancient Egyptian god of darkness and destruction, but there is still a chance that he will not be able to fulfill his fateful destiny. Scientists are 99.7% sure that a boulder will fly past the Earth at a distance of 30-33 thousand kilometers. In astronomical terms, this is something like a flea jump, no more than a flight from New York to Melbourne and back, and much smaller than the diameters of the orbits of many geostationary communications satellites. After dusk, the population of Europe, Africa and Western Asia will be able to observe a celestial object similar to a medium-sized star for a couple of hours, crossing the region of the sky where the constellation Cancer is located. Apophis will be the first asteroid in the history of mankind that we will be able to clearly see with the naked eye. And then it will disappear - it will simply melt into the black expanses of space.

Daily on earth's surface brings about 100 tons of interplanetary matter from space, but only occasionally do we receive such objects that would leave a noticeable mark on Earth. asteroids- rather large space bodies, consisting of rock or metal. They come from relatively warm regions of the interior. solar system somewhere between the orbits of Mars and Jupiter. Comets consist mainly of ice and rocks. They form in the cold regions of the outer solar system, far beyond the orbits of all the planets. There is a hypothesis that billions of years ago they brought the first organic compounds. meteoroids(meteorite bodies) - either fragments of asteroids colliding in outer space, or fragments remaining during the evaporation of comets. If meteoroids reach earth's atmosphere, they are called meteors, and if they fall on the earth's surface, they are called meteorites. Now, 160 craters have been identified on the surface of the Earth, which arose from a collision with cosmic bodies. Here we talk about six of the most notable.

50 thousand years ago, Berringer crater (Arizona, USA), circumference 1230 m

50 thousand years ago, Berringer crater (Arizona, USA), circumference 1230 m - from the fall of a meteorite with a diameter of 50 km. This is the very first meteorite impact crater discovered on Earth. It was called "meteorite" (see photo). In addition, it has been preserved better than others. In the 1960s, astronauts trained here, honing their techniques for collecting soil samples for the Apollo program.

35 million years ago, Chesapeake Bay crater (Maryland, USA), circumference 85 km

35 million years ago, Chesapeake Bay crater (Maryland, USA), circumference 85 km - from the fall of a meteorite 2–3 km in diameter. The largest crater in the United States from a collision with a celestial body. The catastrophe that created it shattered the rock base 2 km deep, creating a reservoir of salt water, which to this day affects the distribution of groundwater flows.

37.5 million years ago, Popigai crater (Siberia, Russia), circumference 100 km

37.5 million years ago, Popigay crater (Siberia, Russia), circumference 100 km - from the fall of an asteroid 5 km in diameter. The crater is strewn with industrial diamonds, which arose as a result of exposure to monstrous pressures on graphite at the time of impact. According to new theory, the asteroid that created this crater, and the Chesapeake meteorite are fragments of the same larger asteroid.

65 million years ago, Chicxulub Basin (Yucatan, Mexico), circumference 175 km

65 million years ago, Chicxulub basin (Yucatan, Mexico), circumference 175 km - from the fall of an asteroid with a diameter of 10 km. The explosion of this asteroid caused tremendous tsunamis and earthquakes of magnitude 10. Scientists believe that it was because of him that dinosaurs died out, as well as 75% of all other animal species that inhabited the Earth. Thus effectively ended the Cretaceous period.

1.85 billion years ago, Sudbury crater (Ontario, Canada), circumference 248 km

1.85 billion years ago, Sudbury crater (Ontario, Canada), circumference 248 km - from the fall of a comet with a diameter of 10 km. At the bottom of the crater, thanks to the heat released during the explosion and the water reserves contained in the comet, a system of hot springs arose, in which life could very likely be supported. Along the perimeter of the crater, the world's largest deposits of nickel and copper ore were found.

2 billion years ago, Vredefort dome (South Africa), circumference 378 km

2 billion years ago, Vredefort dome (South Africa), circumference 378 km - from the fall of a meteorite with a diameter of 10 km. The oldest and (at the time of the disaster) the largest of these craters on Earth. It arose as a result of the most massive release of energy in the entire history of our planet. Perhaps this event changed the course of evolution of unicellular organisms.

Memorable meetings with space bodies - the best historical dates!

Maybe it will pass. But scientists have calculated: if Apophis is exactly 30,404.5 km from our planet, he should fall into the gravitational "keyhole". A strip of space about 1 km wide, a hole comparable in size to the diameter of the asteroid itself, is a trap where the Earth's gravity can turn the flight of Apophis in a dangerous direction, so that our planet will literally be in the crosshairs of the sight at the time of the next visit of this asteroid, which will take place exactly in 7 years - April 13, 2036.
The results of radar and optical tracking of Apophis, when it once again flew past our planet last summer, made it possible to calculate the probability of it falling into the "keyhole". In numerical terms, this chance is 1:45,000! "It's not an easy task to realistically assess a hazard with a very low probability of an event," says Michael de Kay of the Clearinghouse and Hazard Assessment Center at Carnegie Mellon University. “Some believe that since the danger is unlikely, then it’s not worth thinking about it, while others, bearing in mind the seriousness of a possible catastrophe, believe that even the smallest probability of such an event is unacceptable.”
Former astronaut Rusty Schweikart has a lot to say about objects flying in outer space - once, having climbed out of his ship during the Apollo 9 flight in 1969, he himself was such an object. In 2001, Schweikart co-founded the B612 Foundation and is now using it to put pressure on NASA to do something about Apophis as soon as possible. “If we miss our chance,” he says, “it would be criminal negligence.”
Let's say that in 2029 the situation will not be the best. Then, if we do not want the asteroid to crash into the Earth in 2036, we must deal with it on approach and try to move it to the side by tens of thousands of kilometers. Forget about the great technological advances we see in Hollywood movies - in fact, this task far exceeds the current capabilities of mankind. Take at least the ingenious method proposed in the famous "Armageddon", which was released in 1998 - to drill a hole a quarter of a kilometer deep in an asteroid and detonate a nuclear charge right inside. So - technically, this is no easier to implement than time travel. In a real situation, when April 13, 2029 approaches, we will only have to calculate the place where the meteorite fell and begin the evacuation of the population from the doomed region.
According to preliminary estimates, the place of the fall of Apophis falls on a 50 km wide strip that runs through Russia, Pacific Ocean, Central America and goes further into the Atlantic. The cities of Managua (Nicaragua), San José (Costa Rica) and Caracas (Venezuela) are located exactly on this strip, so they are in danger of a direct hit and total destruction. However, the most likely place of impact is a point in the ocean several thousand kilometers from the western coast of America. If Apophis falls into the ocean, a funnel 2.7 km deep and about 8 km in diameter will form in this place, from which tsunami waves will run in all directions. As a result, say, the coast of Florida will be hit by twenty-meter waves, which will bombard the mainland for an hour.
However, it is still too early to think about evacuation. After 2029, we will no longer be able to avoid a collision, but long before fateful minute we can throw Apophis off course just enough to keep it out of the keyhole. According to NASA calculations, a simple “blank” weighing one ton, the so-called kinetic impactor, which should hit the asteroid at a speed of 8000 km / h, will fit for this. A similar mission has already been performed by NASA's Deep Impact space probe (by the way, its name is associated with another 1998 Hollywood blockbuster). In 2005, at the behest of its creators, this device crashed into the nucleus of the comet Tempel 1, and thus information was obtained about the structure of the surface of this cosmic body. Another solution is also possible, when a spacecraft with an ion propulsor, playing the role of a "gravitational tractor", will hover over Apophis, and its - albeit negligible - force of gravity will slightly shift the asteroid from the fatal course.
In 2005, Schweickart urged NASA officials to plan a rescue mission to install a radio transmitter on Apophis. The data regularly obtained from this instrument would confirm the forecasts of the development of the situation. With a favorable forecast (if the asteroid flies past the “keyhole” in 2029), earthly inhabitants could breathe a sigh of relief. In the event of a disappointing forecast, we would have had enough time to prepare and send an expedition into space that would be able to ward off the danger that threatens the Earth. According to Schweikart, it could take about 12 years to complete such a project, but it is desirable to complete all rescue work by 2026 - only then can we hope that the remaining three years will be enough to show positive results from the impact of our rescue ship.

However, NASA still prefers waiting tactics. According to the calculations of Stephen Chesley, who works in Pasadena (California) at the Jet Propulsion Laboratory (JPL) on the topic "Near Earth Object" (Near Earth Project), until 2013 we have every right to not worry about anything. By that time, Apophis will fall into the field of view of the 300-meter radio telescope located in Arecibo (Puerto Rico). Based on these data, it will already be possible to make a reliable forecast - will the asteroid fall into the “keyhole” in 2029 or will it pass by. If our worst fears are confirmed, we will have enough time for an expedition with the installation of a transceiver, and for emergency measures to push the asteroid off a dangerous trajectory. “It’s too early to fuss now,” says Chesley, “but if by 2014 the situation does not resolve itself, then we will start preparing serious expeditions.”
In 1998, the US Congress instructed NASA to search for, record and track all asteroids with a diameter of at least 1 km in near-Earth space. The resulting "Space Security Report" contains a description of 75% of the 1100 alleged objects in existence. (In the course of these searches, Apophis, which did not reach the required size of 750 m, caught the eye of the researchers simply by a lucky chance.) None of the giants included in the "report", fortunately, poses a danger to the Earth. “But in the remaining couple of hundred that we haven’t been able to detect yet, anyone could be on approach to our planet,” says former astronaut Tom Jones, a NASA asteroid search consultant. In light of the current situation, the aerospace agency intends to expand the search criterion to a diameter of 140 m, that is, to capture in its network and celestial bodies half the size of Apophis, capable of cause significant damage to our planet. More than 4,000 such asteroids have already been identified, and according to preliminary NASA estimates, there should be at least 100,000 of them.
As the procedure for calculating the 323-day orbit of Apophis showed, predicting the paths along which asteroids move is troublesome. Our asteroid was discovered in June 2004 by astronomers at the Kitt Peak Arizona National Observatory. A lot of useful information was obtained by amateur astronomers, and after six months, repeated professional observations and more accurate sighting of the object led to such results that JPL sounded the alarm. JPL's holy of holies, the Sentry asteroid tracking system (a super-powerful computer that calculates the orbits of near-Earth asteroids based on astronomical observations) made predictions that looked more and more ominous day by day. Already on December 27, 2004, the estimated chances of an expected collision in 2029 reached 2.7% - such numbers caused a stir in the narrow world of asteroid hunters. Apophis took an unprecedented 4th step on the Turin scale.
However, the panic quickly subsided. The results of those observations that had previously eluded the attention of researchers were entered into the computer, and the system announced a reassuring message: in 2029, Apophis will fly past the Earth, but will miss by the slightest. Everything would be fine, but one unpleasant trifle remained - that very “keyhole”. The tiny size of this gravitational "trap" (only 600 m in diameter) is both a plus and a minus. On the one hand, it will not be so difficult to push Apophis away from such an insignificant goal. If we believe the calculations, then by changing the speed of the asteroid by only 16 cm per hour, that is, by 3.8 m per day, in three years we will shift its orbit by several kilometers. It seems to be nonsense, but quite enough to bypass the keyhole. Such influences are quite within the power of the already described "gravitational tractor" or "kinetic blank". On the other hand, when we are dealing with such a tiny target, it is impossible to accurately predict in which direction Apophis will deviate from the keyhole. Today, predictions of what the orbit will be like by 2029 have an accuracy scale (in space ballistics it is called the "ellipse of errors") of about 3000 km. As new data accumulates, this ellipse should gradually decrease. In order to say with any certainty that Apophis is flying past, it is necessary to reduce the "ellipse" to a size of about 1 km. Lacking the necessary information, the rescue expedition may take the asteroid to the side, or may unintentionally drive it into the well itself.
But is it realistic to achieve the required forecasting accuracy? This task involves not only the installation of a transceiver on the asteroid, but also a mathematical model that is incomparably more complex than the one currently used. The new orbit calculation algorithm should also include such seemingly insignificant factors as solar radiation, terms added to account for relativistic effects, and gravitational influence from other nearby asteroids. In the current model, all these corrections have not yet been taken into account.
And finally, when calculating this orbit, another surprise awaits us - the Yarkovsky effect. It's extra small but steady acting force- its manifestation is observed in those cases when an asteroid radiates more heat from one side than from the other. As the asteroid turns away from the Sun, it begins to radiate the heat accumulated in the surface layers into the surrounding space. There is a weak, but still noticeable reactive force acting in the opposite direction to the heat flow. For example, twice as large an asteroid called 6489 Golevka under the influence of this force over the past 15 years has moved away from the calculated orbit by 16 km. No one knows how this effect will affect the trajectory of Apophis over the next 23 years. At the moment, we have no idea either about the speed of its rotation, or about the direction of the axis around which it could rotate. We do not even know its outlines - and this information is absolutely necessary in order to calculate the Yarkovsky effect.

Fortunately, in order for Apophis not to fall into the gravitational “keyhole” hiding in space on the outskirts of the Earth and ready to send it directly to our planet on the next turn, it will be enough to move it just a kilometer or two. If we were immediately threatened with a direct collision, the asteroid would need to be “shifted” by 8-10 thousand kilometers and this would require 10,000 times more energy. And so the task seems to be within our power - even with the use of current technology. Several methods are proposed to solve it.

Strong frontal impact

A spacecraft with a head part, which is a simple blank weighing 1 ton (“kinetic striker”), will simply crash into Apophis at a speed of 8000 km / h and, according to calculations, will change the speed of an asteroid weighing 50 million tons by only 16 cm per hour. Over the course of three years, the effect of this seemingly negligible change in speed will accumulate and result in a displacement of several kilometers. Advantages. We already know how to do it: last summer, the Deep Impact probe was launched in a similar way to collide with the nucleus of a comet. Reverse side. As a result of the collision, fragments can break off from the asteroid. In addition, if the impact does not hit exactly at the center of mass, we will achieve not the displacement of the celestial body, but its rotation.

Orbit change by pusher

Plasma or ion rocket engine powered by nuclear reactor or from solar panels, can be fixed directly on the surface of the asteroid. If it works for at least a few weeks, creating a thrust of one or two newtons, this will already be enough for the asteroid's speed to change by the required tens of centimeters per hour. Advantages. The design of the ion engine has already been tested during the Deep Space 1 expedition in 1998, the design of plasma engines - during numerous launches of commercial telecommunications satellites and the Smart-1 lunar probe. Reverse side. The spacecraft needs a "soft landing" and a hard anchorage on a surface with unknown properties. Since the asteroid rotates, in order for the thrust to act in only one direction, the device will need a complex system management.

Tractor impact

A 1-ton "gravity tractor" using a solar-powered ion (or plasma) drive or hydrazine thrusters will hover a quarter of a kilometer above the asteroid's surface. The force of gravity of the spacecraft will gradually drag the asteroid away from its trajectory - in fact, the thrust of the engines (that is, several grams of force) will be partially transferred to the celestial body within a month. Advantages. If necessary, all these movements can be controlled. For a gravity tractor (as opposed to a rigidly fixed pusher), the problems associated with the rotation of the asteroid do not matter. Reverse side. Soaring above the surface is a very unstable position.

Undermining a nuclear charge

If a thermonuclear bomb is planted in the bowels of Apophis, it will turn it into a swarm of small asteroids. Advantages. A feeling of deep satisfaction from the mere thought that the enemy has been smashed to smithereens. Reverse side. deep drilling in open space we've never done it before. Besides, wouldn't a bunch of small radioactive asteroids be even worse than one big one?

Nuke frying

It is better to arrange a nuclear explosion directly above the asteroid. Evaporation of matter from the surface of a celestial body will push it in the opposite direction. Advantages. In such a situation, the rotation of the asteroid will not play a role. Reverse side. At present, the international ban on the use of nuclear weapons in space remains in force, and the accumulation of nuclear warheads to protect against asteroids could harm the overall process of nuclear disarmament.

How to get rid of a pesky asteroid

If the apophys is really aiming straight for the gravitational "keyhole", ground-based observations will not be able to confirm this until at least 2021. It may be too late to take any action by then. Let's see what is at stake (Chesley believes that the fall of such an asteroid should entail losses of $ 400 billion only due to damage to the economic infrastructure), and it will immediately become clear that some steps must be taken to protect against an impending catastrophe now, without waiting for confirmation that they will eventually be needed. When will we start? Or, if you look from the other side, at what point can you rely on luck and say that the trouble has passed? When are the chances of a successful outcome ten to one? Thousand to one?
When NASA discovers a potentially hazardous asteroid like Apophis, it is not empowered to make decisions about how to proceed. “Rescue planning is not our business,” Chesley says. The first and very timid step of the space agency in this direction was a kind of working meeting, at which in June 2006 possible measures for protection against asteroids were discussed.
If these NASA efforts deserve attention, approval, and, most importantly, funding from the US Congress, then the next step will immediately be sending a reconnaissance expedition to Apophis. Schweikart notes that even if the planned "gravity tractor" equipped with a control transceiver is "covered in gold from nose to tail", its launch is unlikely to cost more than a quarter of a billion. By the way, the release of space fantasy "Armageddon" and "Collision with the abyss" cost the same amount. If, in the name of protecting our planet, Hollywood was not stingy to lay out such money, then is it really not possible for the US Congress to find it? (Author: David Noland)

Asteroid Apophis in the theory of the apocalypse represents big event when it comes to impacting the Earth. In particular, if we assume a collision of a large asteroid with the Earth, this will be a terrible destruction of the planet. Apophis is really a large celestial body so much so that scientists compare the collision with an explosion nuclear bomb.

Can a huge asteroid collide with Earth? This has already happened in planetary history and, of course, the catastrophe can happen again. Fortunately, today there is no threat of an asteroid attack. At least space observers convince us of this.

Apophis was discovered by two researchers from the Kitt Peak National Observatory in Arizona, USA. They noticed showing off in June of the year two thousand and four.

At first, Apophis was designated 2004 MN4. Then received the nomenclature 99942 after an accurate study of its orbit was made and a calculation was made.

After some time, he was called by his own name Apophis (Apophis). Presumably because the scientists who discovered it were fanatics of a TV series related to the space where this name was mentioned.

Apophis - today it is an asteroid, the collision of which with the Earth can arrange a planetary catastrophe. The event, of course, will not erase the human race from the list of the Universe, but the consequences for the life of the planet will be terrible.

Astronomers are sure that the asteroid Apophis is one of the most powerful threats to the life of mankind on planet Earth.

The huge space rock keeps its orbit very close to our planet. The trajectory of an asteroid in its journey crosses the orbit of our planet twice each time it completes its journey around the Sun.

How dangerous is Apophis for the Earth?

Since its discovery, it was believed that there was a strong threat to the Earth. Because the giant stone is making its way towards our planet. At first, there was even an assumption that he was going to enter into a gravitational confrontation with the Earth. This could change the orbit of Apophis so much that the asteroid would collide with the planet.

The composition of this asteroid in megatons is so exorbitant that it can be compared to twice the energy, Krakatoa. But the volcano that raged then led to a global change in the Earth's climate for almost 5 years in the 19th century.

From the latest observations made by the European Space Agency (ESA) and NASA reports of a possible collision of Apophis with the Earth, the event is excluded. However, it is estimated that it can generate an energy release of 900 megatons!

It could be a catastrophe that looks worse than the most powerful nuclear bomb ever created by man. April 13, 2029, the closest date when Apophis will be as close as possible to Earth, fortunately, there is no danger to the planet in this.

The exact time of a possible Apocalypse is already known to the second. Friday, April 13, 2029 at 4.36 am GMT. Concealing the energy of 65 thousand atomic bombs Apophis asteroid with a mass of 50 million tons and a diameter of 320 meters will cross the orbit of the Moon and rush towards the Earth at a speed of 45 thousand kilometers per hour.

Russian astronomers have calculated the date of a possible collision of the asteroid Apophis with the Earth, but they consider the probability of this to be negligible ( but it is there, and who canceled the silence of the truth so that there was no panic ), said Leonid Sokolov, professor at the Department of Celestial Mechanics at St. Petersburg State University, speaking at the Royal Academic Readings on astronautics.

"April 13 ( and it's Friday ) 2029 Apophis will approach the Earth at a distance of 37-38 thousand kilometers. Its possible impact with the Earth may occur on April 13, 2036," Sokolov said. According to him, other scientists, in particular employees of the Institute of Applied Astronomy of the Russian Academy of Sciences, believe that the probability of Apophis impacting the Earth in 2036 is negligible.

According to the calculations of the American space agency NASA, which Sokolov cited in the report, 11 collisions with the Earth are possible in the 21st century, 4 of which should occur before 2050 ( and this applies to us ).

"After the close approach of Apophis to the Earth in 2036, it can move to various resonant orbits, including rendezvous orbits (with the Earth), but it does not mean that the asteroid will collide with the Earth in 2036, it can disperse into particles, and their collision with the Earth can happen in the coming years," Sokolov noted.

"Our task is to consider various alternatives, develop scenarios and appropriate actions depending on the results of future observations of Apophis," Sokolov added.

Apophis - one of the most dangerous asteroids, was discovered by scientists in June 2004. The diameter of the asteroid is 270 meters. If it even falls into the ocean, the funnel will be 8 km in diameter and 2-3 km deep. A wave 20 meters high will hit America.
With the help of updated information, NASA scientists have recalculated the orbit of motion for the asteroid Apophis. The newly calculated trajectory significantly reduces the likelihood of a dangerous collision with the Earth in 2036. The new data points to the probability of a meeting of the Earth on April 13, 2036 with the asteroid Apophis, but the probability of a collision has decreased from 1:45,000 to approximately 1:4,000,000.

Initially, the chances of Apophis approaching and colliding with the Earth were estimated at 2.7% in 2029. However, the record distance at which the asteroid Apophis will approach the Earth on Friday, April 13, 2029 is expected to be about 25,000 km.

According to preliminary estimates, after the impact of the asteroid Apophis on the Earth's surface, a 200-megaton explosion will occur, which can give rise to a global tsunami with waves of almost 12 meters in height, which will sweep away everything in its path at a distance of up to 50 kilometers inland.

The name of this asteroid speaks for itself - that was the name of the ancient Egyptian god of darkness and destruction, but there is still a chance that he will not be able to fulfill his fateful destiny. Scientists are 99.7% sure that a boulder will fly past the Earth at a distance of 30-33 thousand kilometers. In astronomical terms, this is something like a flea jump, no more than a flight from New York to Melbourne and back, and much smaller than the diameters of the orbits of many geostationary communications satellites. After dusk, the population of Europe, Africa and Western Asia will be able to observe a celestial object similar to a medium-sized star for a couple of hours, crossing the region of the sky where the constellation Cancer is located. Apophis will be the first asteroid in the history of mankind that we will be able to clearly see with the naked eye. And then it will disappear - it will simply melt into the black expanses of space.

The results of radar and optical tracking of Apophis, when it once again flew past our planet last summer, made it possible to calculate the probability of it falling into the "keyhole". In numerical terms, this chance is 1:45,000! "It's not an easy task to realistically assess a hazard with a very low probability of an event," says Michael de Kay of the Clearinghouse and Hazard Assessment Center at Carnegie Mellon University. “Some believe that since the danger is unlikely, then it’s not worth even thinking about it, while others, bearing in mind the seriousness of a possible catastrophe, believe that even the smallest probability of such an event is unacceptable.”
Former astronaut Rusty Schweikart has a lot to say about objects flying in outer space - once, having climbed out of his ship during the Apollo 9 flight in 1969, he himself was such an object. In 2001, Schweikart co-founded the B612 Foundation and is now using it to put pressure on NASA to do something about Apophis as soon as possible. “If we miss the opportunity that has been given to us,” he says, “it will be criminal negligence.”

Let's say that in 2029 the situation will not be the best. Then, if we do not want the asteroid to crash into the Earth in 2036, we must deal with it on approach and try to move it to the side by tens of thousands of kilometers. Forget about the great technological advances we see in Hollywood movies - in fact, this task far exceeds the current capabilities of mankind. Take, for example, the ingenious method proposed in the famous "Armageddon", which was released on screens in 1998 - to drill a hole a quarter of a kilometer deep in an asteroid and detonate a nuclear charge right inside. So - technically, this is no easier to implement than time travel. In a real situation, when April 13, 2029 approaches, we will only have to calculate the place where the meteorite fell and begin the evacuation of the population from the doomed region.

According to preliminary estimates, the site of the fall of Apophis falls on a 50 km wide strip that runs through Russia, the Pacific Ocean, Central America and goes further into the Atlantic. The cities of Managua (Nicaragua), San José (Costa Rica) and Caracas (Venezuela) are located exactly on this strip, so they are in danger of a direct hit and total destruction. However, the most likely place of impact is a point in the ocean several thousand kilometers from the western coast of America. If Apophis falls into the ocean, a funnel 2.7 km deep and about 8 km in diameter will form in this place, from which tsunami waves will run in all directions. As a result, say, the coast of Florida will be hit by twenty-meter waves, which will bombard the mainland for an hour.

However, it is still too early to think about evacuation. After 2029, we will no longer be able to avoid a collision, but long before the fateful moment we can slightly knock Apophis off course - just enough so that he does not fall into the "keyhole". According to NASA calculations, a simple “blank” weighing one ton, the so-called kinetic impactor, which should hit the asteroid at a speed of 8000 km / h, will fit for this. A similar mission has already been performed by NASA's Deep Impact space probe (by the way, its name is associated with another 1998 Hollywood blockbuster). In 2005, at the behest of its creators, this apparatus crashed into the nucleus of the Tempel 1 comet, and thus information was obtained about the structure of the surface of this cosmic body. Another solution is also possible, when a spacecraft with an ion propulsor, playing the role of a "gravitational tractor", will hover over Apophis, and its - albeit negligible - force of gravity will slightly shift the asteroid from the fatal course.

In 2005, Schweickart urged NASA officials to plan a rescue mission to install a radio transmitter on Apophis. The data regularly obtained from this instrument would confirm the forecasts of the development of the situation. With a favorable forecast (if the asteroid flies past the “keyhole” in 2029), earthly inhabitants could breathe a sigh of relief. In the event of a disappointing forecast, we would have had enough time to prepare and send an expedition into space that would be able to ward off the danger that threatens the Earth. According to Schweikart, such a project could take about 12 years to complete, but it is desirable to complete all rescue work by 2026 - only then can we hope that the remaining three years will be enough to show positive results from the impact of our planet, barely noticeable on a cosmic scale. rescue ship.

In 1998, the US Congress instructed NASA to search for, record and track all asteroids with a diameter of at least 1 km in near-Earth space. The resulting "Space Security Report" contains a description of 75% of the 1100 alleged objects in existence. (In the course of these searches, Apophis, which did not reach the required size of 750 m, caught the eye of the researchers simply by a lucky chance.) None of the giants included in the "report", fortunately, poses a danger to the Earth. "But in the remaining couple of hundred that we haven't been able to detect yet, anyone could be on approach to our planet," says former astronaut Tom Jones, a NASA asteroid search consultant. In light of the current situation, the aerospace agency intends to expand the search criterion to a diameter of 140 m, that is, to capture into its network and celestial bodies half the size of Apophis, which can nevertheless cause significant damage to our planet. More than 4,000 such asteroids have already been identified, and according to preliminary NASA estimates, there should be at least 100,000 of them.

As the procedure for calculating the 323-day orbit of Apophis showed, predicting the paths along which asteroids move is a troublesome business. Our asteroid was discovered in June 2004 by astronomers at the Kitt Peak Arizona National Observatory. A lot of useful information was obtained by amateur astronomers, and after six months, repeated professional observations and more accurate sighting of the object led to such results that JPL sounded the alarm. JPL's holy of holies, the Sentry asteroid tracking system (a super-powerful computer that calculates the orbits of near-Earth asteroids based on astronomical observations) made predictions that looked more and more ominous day by day. Already on December 27, 2004, the calculated chances of an expected collision in 2029 reached the level of 2.7% - such figures caused a stir in the narrow world of asteroid hunters. Apophis took an unprecedented 4th step on the Turin scale.

However, the panic quickly subsided. The results of those observations that had previously eluded the attention of researchers were entered into the computer, and the system announced a reassuring message: in 2029, Apophis will fly past the Earth, but will miss by the slightest. Everything would be fine, but one unpleasant little thing remained - that very “keyhole”. The tiny size of this gravitational "trap" (only 600 m in diameter) is both a plus and a minus. On the one hand, it will not be so difficult to push Apophis away from such an insignificant goal. If we believe the calculations, then by changing the speed of the asteroid by only 16 cm per hour, that is, by 3.8 m per day, in three years we will shift its orbit by several kilometers. It seems to be nonsense, but quite enough to bypass the keyhole. Such influences are quite within the power of the already described "gravitational tractor" or "kinetic blank". On the other hand, when we are dealing with such a tiny target, it is impossible to accurately predict in which direction Apophis will deviate from the keyhole. Today, predictions of what the orbit will be like by 2029 have an accuracy scale (in space ballistics it is called the "ellipse of errors") of about 3000 km. As new data accumulates, this ellipse should gradually decrease. In order to say with any certainty that Apophis is flying past, it is necessary to reduce the "ellipse" to a size of about 1 km. Lacking the necessary information, the rescue expedition may take the asteroid to the side, or may unintentionally drive it into the well itself.

But is it realistic to achieve the required forecasting accuracy? This task involves not only the installation of a transceiver on the asteroid, but also a mathematical model that is incomparably more complex than the one currently used. The new orbit calculation algorithm should also include such seemingly insignificant factors as solar radiation, terms added to account for relativistic effects, and gravitational influence from other nearby asteroids. In the current model, all these corrections have not yet been taken into account.

And finally, when calculating this orbit, another surprise awaits us - the Yarkovsky effect. This is an additional small but steadily acting force - its manifestation is observed in those cases when an asteroid radiates more heat from one side than from the other. As the asteroid turns away from the Sun, it begins to radiate the heat accumulated in the surface layers into the surrounding space. There is a weak, but still noticeable reactive force acting in the opposite direction to the heat flow. For example, twice as large an asteroid called 6489 Golevka under the influence of this force over the past 15 years has moved away from the calculated orbit by 16 km. No one knows how this effect will affect the trajectory of Apophis over the next 23 years. At the moment, we have no idea either about the speed of its rotation, or about the direction of the axis around which it could rotate. We do not even know its outlines - and yet this information is absolutely necessary in order to calculate the Yarkovsky effect.

When NASA discovers a potentially hazardous asteroid like Apophis, it is not empowered to make decisions about how to proceed. "Rescue planning is not our business," says Chesley. The space agency's first and very timid step in this direction was a kind of working meeting at which possible measures for protection against asteroids were discussed in June 2006.

If these NASA efforts deserve attention, approval, and, most importantly, funding from the US Congress, then the next step will immediately be sending a reconnaissance expedition to Apophis. Schweikart notes that even if the planned "gravity tractor" equipped with a control transceiver is "covered in gold from nose to tail", its launch is unlikely to cost more than a quarter of a billion. By the way, the release of space fantasy "Armageddon" and "Collision with the abyss" cost the same amount. If, in the name of protecting our planet, Hollywood was not stingy to lay out such money, then is it really not possible for the US Congress to find it? (Author: David Noland)

In general, somewhere in China, giant ships are definitely already being built and tickets are already on sale

How dangerous is Apophis for the Earth?

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