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Asteroid danger

An asteroid is a relatively small celestial body solar system, moving in orbit around the Sun. Asteroids are significantly inferior in mass and size to planets and have irregular shape and have no atmosphere.

Currently, hundreds of thousands of asteroids have been discovered in the Solar System. As of 2015, there were 670,474 objects in the database, of which 422,636 had precisely determined orbits and assigned an official number, more than 19,000 of them had officially approved names. It is estimated that there may be from 1.1 to 1.9 million objects in the Solar System that are larger than 1 km. Most known on at the moment asteroids are concentrated within the asteroid belt, located between the orbits of Marsai and Jupiter.

Ceres, measuring approximately 975 x 909 km, was considered the largest asteroid in the Solar System, but since August 24, 2006, it received the status of a dwarf planet. The other two largest asteroids, Pallas and Vesta, have a diameter of ~500 km. Vesta is the only object in the asteroid belt that can be observed with the naked eye. Asteroids moving in other orbits can also be observed during their passage near the Earth.

The total mass of all main belt asteroids is estimated at 3.0-3.6·1021 kg, which is only about 4% of the mass of the Moon. The mass of Ceres is 9.5 1020 kg, that is, about 32% of the total, and together with the three largest asteroids Vesta (9%), Pallas (7%), Hygeia (3%) - 51%, that is, the vast majority of asteroids have an insignificant mass by astronomical standards.

However, asteroids are dangerous for planet Earth, since a collision with a body larger than 3 km can lead to the destruction of civilization, despite the fact that the Earth is much larger than all known asteroids.

Almost 20 years ago, in July 1981, NASA (USA) held the first Workshop “Collisions of Asteroids and Comets with the Earth: Physical Consequences and Humanity,” at which the problem of the asteroid-comet hazard received “official status.” From then to the present, at least 15 international conferences and meetings devoted to this problem have been held in the USA, Russia, and Italy. Realizing that priority Its solution is the detection and cataloging of asteroids in the vicinity of the Earth's orbit, astronomers in the USA, Europe, Australia and Japan began to make vigorous efforts to set up and implement appropriate observational programs.

Along with special scientific and technical conferences, these issues were considered by the UN (1995), the UK House of Lords (2001), the US Congress (2002) and the Organization for Economic Cooperation and Development (2003). As a result of this, a number of decrees and resolutions were adopted on this problem, the most important of which is Resolution 1080 “On the detection of asteroids and comets potentially dangerous to humanity,” adopted in 1996 by the Parliamentary Assembly of the Council of Europe.

It is obvious that you need to be prepared in advance for a situation where you need to make quick and error-free decisions to save millions and even billions of people. Otherwise, given the lack of time, state disunity and other factors, we will not be able to accept adequate and effective measures protection and salvation. In this regard, it would be unforgivably careless not to take effective measures to prevent such events. Moreover, Russia and others, technologically developed countries the world has all the basic technologies to create a Planetary Defense System (PPS) against asteroids and comets.

However, the global and complex nature of the problem makes it impossible for any single country to create and maintain such a protection system in constant readiness. It is obvious that since this problem is universal, it must be solved by the joint efforts and means of the entire world community.

It should be noted that in a number of countries certain funds have already been allocated and work has begun in this direction. At the University of Arizona (USA), under the leadership of T. Gehrels, a technique for monitoring NEAs has been developed and since the late 80s, observations have been carried out using a 0.9-m telescope with a CCD matrix (2048x 2048) at the Kitt Peak National Observatory. The system has proven its effectiveness in practice - about one and a half hundred new NEAs, with sizes up to several meters, have already been discovered. To date, work has been completed to transfer the equipment to the 1.8-m telescope of the same observatory, which will significantly increase the rate of detection of new NEAs. Monitoring of NEAs has begun under two more programs in the United States: at the Lovell Observatory (Flagstaff, Arizona) and in the Hawaiian Islands (a joint NASA-US Air Force program using the 1-m ground-based Air Force telescope). In the south of France, at the Côte d'Azur Observatory (Nice), the European NEA Monitoring Program has been launched, in which France, Germany and Sweden are involved. Similar programs are also being staged in Japan.

When a large celestial body falls onto the Earth's surface, craters are formed. Such events are called astroproblems, “star wounds”. On Earth they are not very numerous (compared to the Moon) and are quickly smoothed out under the influence of erosion and other processes. A total of 120 craters have been found on the surface of the planet. 33 craters have a diameter of more than 5 km and are about 150 million years old.

The first crater was discovered in the 1920s in Devil's Canyon in the North American state of Arizona. Fig. 15 The diameter of the crater is 1.2 km, depth is 175 m, approximate age is 49 thousand years. According to scientists' calculations, such a crater could have formed when the Earth collided with a body of forty meters in diameter.

Geochemical and paleontological data indicate that approximately 65 million years ago at the turn of the Mesozoic period of the Cretaceous era and Tertiary period During the Cenozoic era, a celestial body approximately 170-300 km in size collided with the Earth in the northern part of the Yucatan Peninsula (coast of Mexico). The trace of this collision is a crater called Chicxulub. The power of the explosion is estimated at 100 million megatons! This created a crater with a diameter of 180 km. The crater was formed by the fall of a body with a diameter of 10-15 km. At the same time, a gigantic cloud of dust weighing a total of one million tons was thrown into the atmosphere. The six-month night has arrived on Earth. More than half of the existing plant and animal species died. Perhaps then, as a result of global cooling, dinosaurs became extinct.

According to modern science In just the last 250 million years, there have been nine extinctions of living organisms with an average interval of 30 million years. These disasters can be associated with the fall of large asteroids or comets to Earth. Let us note that it is not only the Earth that suffers from uninvited guests. Spacecraft photographed the surfaces of the Moon, Mars, and Mercury. The craters are clearly visible on them, and they are much better preserved due to the peculiarities of the local climate.

On the territory of Russia, several astroproblems stand out: in the north of Siberia - Popigaiskaya - with a crater diameter of 100 km and an age of 36-37 million years, Puchezh-Katunskaya - with a crater of 80 km, whose age is estimated at 180 million years, and Karskaya - with a diameter of 65 km and age - 70 million years. celestial asteroid Tunguska

Tunguska phenomenon

Two large celestial bodies fell to Russian Earth in the 20th century. Firstly, the Tunguska object, which caused an explosion with a power of 20 megatons at an altitude of 5-8 km above the Earth's surface. To determine the power of an explosion, it is equated by its destructive effect on environment explosion of a hydrogen bomb with TNT equivalent, in this case 20 megatons of TNT, which exceeds the energy nuclear explosion in Hiroshima 100 times. By modern estimates the mass of this body could reach from 1 to 5 million tons. An unknown body invaded the earth's atmosphere on June 30, 1908 in the Podkamennaya Tunguska River basin in Siberia.

Since 1927, eight expeditions of Russian scientists successively worked at the site of the fall of the Tunguska phenomenon. It was determined that within a radius of 30 km from the explosion site, all the trees were knocked down by the shock wave. Radiation burn caused a huge forest fire. The explosion was accompanied strong sound. Over a vast territory, according to the testimony of residents of the surrounding (very rare in the taiga) villages, unusually light nights were observed. But none of the expeditions found a single piece of the meteorite.

Many people are more accustomed to hearing the phrase “Tunguska meteorite,” but until the nature of this phenomenon is reliably known, scientists prefer to use the term “Tunguska phenomenon.” Opinions about the nature of the Tunguska phenomenon are the most controversial. Some consider it to be a stone asteroid with a diameter of approximately 60-70 meters, which collapsed when falling into pieces of approximately 10 meters in diameter, which then evaporated in the atmosphere. Others, and most of them, say that this is a fragment of Comet Encke. Many associate this meteorite with the Beta Taurid meteor shower, the ancestor of which is also Comet Encke. Proof of this can be the fall of two other large meteors to Earth in the same month of the year - June, which were not previously considered on a par with Tunguska. We are talking about the Krasnoturansky bolide of 1978 and the Chinese meteorite of 1876.

A realistic estimate of the energy of the Tunguska phenomenon is approximately 6 megatons. The energy of the Tunguska phenomenon is equivalent to an earthquake with a magnitude of 7.7 (the energy of the strongest earthquake is 12).

The second large object found on Russian territory was the Sikhote-Alin iron meteorite, which fell in the Ussuri taiga on February 12, 1947. It was significantly smaller than its predecessor, and its mass was tens of tons. It also exploded in the air before reaching the surface of the planet. However, over an area of 2 square kilometers, more than 100 craters with a diameter of just over a meter were discovered. The largest crater found was 26.5 meters in diameter and 6 meters deep. Over the past fifty years, over 300 large fragments have been found. The largest fragment weighs 1,745 kg, and the total weight of the collected fragments exceeded 30 tons of meteoric material. Not all the fragments were found. The energy of the Sikhote-Alinin meteorite is estimated at about 20 kilotons.

Russia was lucky: both meteorites fell in a deserted area. If the Tunguska meteorite fell on big city, then nothing remained of the city and its inhabitants.

Of the large meteorites of the 20th century, the Brazilian Tunguska deserves attention. He fell on the morning of September 3, 1930 in a deserted area of the Amazon. The power of the explosion of the Brazilian meteorite corresponded to one megaton.

All of the above concerns collisions of the Earth with a specific solid body. But what can happen in a collision with a comet of huge radius filled with meteorites? The fate of the planet Jupiter helps answer this question. In July 1996, Comet Shoemaker-Levy collided with Jupiter. Two years earlier, during the passage of this comet at a distance of 15 thousand kilometers from Jupiter, its core split into 17 fragments of approximately 0.5 km in diameter, stretching along the comet’s orbit. In 1996, they one by one penetrated into the thickness of the planet. The collision energy of each piece, according to scientists, reached approximately 100 million megatons. In photographs from the space telescope. Hubble (USA) shows that as a result of the catastrophe, giant dark spots formed on the surface of Jupiter - emissions of gas and dust into the atmosphere in places where fragments burned. The spots corresponded to the size of our Earth!

Of course, comets also collided with the Earth in the distant past. It is collisions with comets, and not with asteroids or meteorites, that are credited with the role of gigantic catastrophes of the past, with climate change, the extinction of many species of animals and plants, and the death of developed civilizations of earthlings. There is no guarantee that the same changes in nature will not occur after an asteroid falls on Earth.

Due to the fact that there is a possibility of asteroids falling to the ground, it is necessary to create a protective installation, which should consist of two automated devices:

A tracking device for asteroids approaching the Earth;

A coordination center on earth that will control missiles to fragment the asteroid into smaller parts that cannot harm nature or humanity. The first should be a satellite (ideally several satellites) located in the orbit of our planet and constantly monitoring celestial bodies flying by. When a dangerous asteroid approaches, the satellite must transmit a signal to a coordination center located on Earth.

The center will automatically determine the flight path and launch a rocket that will break a large asteroid into smaller ones, thereby preventing global catastrophe in a collision.

That is, it is necessary for scientists to develop specific automated mechanisms that will control the movement of celestial bodies, and in particular those approaching our planet, and prevent global catastrophes.

The problem of asteroid danger is international in nature. The most active countries in solving this problem are the USA, Italy and Russia. A positive fact is that cooperation on this issue is being established between nuclear specialists and the military of the United States and Russia. Military departments largest countries is really able to unite its efforts to solve this problem of humanity - the asteroid danger and, as part of the conversion, begin to create a global system for protecting the Earth. This cooperative cooperation would contribute to the growth of trust and detente in international relations, the development of new technologies, the further technical progress society.

It is noteworthy that the awareness of the reality of the threat of cosmic collisions coincided with a time when the level of development of science and technology already makes it possible to put on the agenda and solve the problem of protecting the Earth from asteroid danger. This means that there is no hopelessness for earthly civilization in the face of a threat from outer space or, in other words, we have a chance to protect ourselves from collisions with dangerous space objects. Asteroid danger is among the most important global problems, which humanity will inevitably have to solve through the combined efforts of various countries.

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No matter how skeptical people are about the Hollywood story about a giant asteroid falling to Earth, space can still pose a serious danger to our planet. The most real threat, by and large, comes precisely from the depths of the vast Universe.

Scientists have found that in the history of the planet, collisions with asteroids have repeatedly occurred, and with quite serious consequences. This explains the attention of scientists to dangerous asteroids. Such asteroids include those whose hypothetical collision with our planet could lead to the death of humanity. Thus, NASA scientists have identified over 150 celestial bodies that pose a potential threat to human civilization.

The topic of “asteroid attacks” has relatively recently begun to occupy scientists. Thus, meteorite falls until the second half of the 18th century were taken as an optical illusion. Back in the 1960s, experts tried to explain the appearance of craters by “earthly” reasons. Now their cosmic origin is beyond any doubt.

Thus, the death of dinosaurs is recorded on the “conscience” of an asteroid whose diameter was about 15 kilometers. 65 million years ago, a collision with this asteroid, along with dinosaurs, sent about 85% of plant and animal species to the next world. As a result of the fall of this giant asteroid, a crater was formed, the diameter of which was 200 kilometers. Billions of tons of water vapor and dust, as well as ash and soot from the monstrous fire rose into the atmosphere. All this obscured the sunlight for many months. This could lead to a catastrophic drop in temperature on Earth.

There are many predictions and facts that point to the end of the world in 2012. But no one knows exactly how this will happen. The Earth is just a crumb in the Universe, which appeared as a result of the interaction of cosmic bodies, and it is possible that it will also disappear. The fall of an asteroid, most likely, will not destroy the planet itself, but will rid it of people, animals and plants, i.e. from life. Will the Earth break into a lot of fragments? Or maybe it will turn into Mars? For now, we can only speculate on this matter, based on the data that NASA shares with the general public.

Asteroids and comets often fly in quite dangerous proximity to the Earth, and even the most minor violation their trajectories can lead to unpredictable consequences. So, if a comet falls on glaciers, it will cause them to melt, global warming, and floods. Some scientists claim that in the entire history of planet Earth it has collided with an asteroid about 6 times. This is evidenced by craters, the origin of which can only be explained by the fall of an asteroid to Earth.

The consequences of an asteroid fall can be very different. It all depends on the size of the asteroid, where it hits, and how fast it moves. So, for example, an asteroid with a diameter of about 500 km will lead to the death of all life on Earth, and within 24 hours. The impact force will cause a firestorm that will destroy all living things in its path. In less than 24 hours, a wave of death will circle the planet and destroy all life on it. It is likely that the simplest organisms will survive and begin the process of evolution on Earth again.

An asteroid with a smaller diameter, if it falls into the ocean, can cause a giant tsunami up to 100 meters high. Such a wave can wash away kilometers of the coastal zone from the face of the planet. Such a tsunami, among other things, can cause a number of man-made disasters. If an asteroid falls on any continent, it will immediately destroy a gigantic part of the land. All life on the planet will die as a result.

Should we expect such an end of the world? Amy Mainzer, one of the employees of NASA's Jet Propulsion Laboratory, claims that hundreds of asteroids are currently revolving around the Earth, capable of destroying all life on the planet. The chances of a planet colliding with an asteroid, according to calculations, are now low. However, one cannot be completely sure of this, since space is absolutely unpredictable. Perhaps a dangerous asteroid is flying towards Earth at this very moment. Technologies are now developing quite quickly, however, despite this, there is still no system that could provide accurate information regarding the movement of all cosmic bodies. But to imagine the full power of the potential danger, it is enough to look at the location of the asteroid belt relative to our planet.

Mars is closest to the belt. At the moment, there is a lot of evidence that there was once life on this planet, but for unknown reasons it died. The most likely version of death is the fall of an asteroid. The powerful wave formed upon impact destroyed all living things. The next victim could well be the Earth, since it is quite close to the asteroid belt.

Scientists such as Morrison and Chapman claim that once every 500 thousand years the planet experiences global catastrophe due to asteroid impacts. According to statistics, asteroids larger than 10 kilometers fall every 100 million years. They leave almost no chance for humanity and the animal world to survive. Scientists believe that if such a collision occurs in our time, all of humanity will perish. According to experts, the biggest threat comes from celestial bodies with average value. According to experts, over 500 thousand years, more than a billion people died as a result of the falls of such bodies. The Earth was constantly bombarded by space.

Currently, according to scientists, the most dangerous asteroids for our planet are asteroids such as asteroid YU 55, Eros, Vesta and Apophis. The fact that there is a real threat from space began to be discussed only when the asteroid Apophis was discovered. Its diameter is approximately 270 meters and its weight is about 27 million tons. The collision of this asteroid with the Earth, according to the latest data, is possible in 2036. Even if it does not fall to Earth, it can cause significant damage to space technology. It will approach the Earth at a distance of 30-35 thousand kilometers, and it is at this altitude that most spacecraft operate. Apophis is currently considered the first among potentially dangerous celestial bodies. In 2013, it will fly relatively close to our planet and scientists will be able to see the true nature of the threat and determine whether it is possible to somehow prevent a catastrophe.

Russian scientists did not wait until 2013 and created a group to decide what to do if it turns out that Apophis will collide with the Earth after all. The approach of the asteroid to the Earth in 2029 will change its orbit, for this reason forecasts about the subsequent direction of movement are very uncertain without more data. After the asteroid hits the Earth's surface, according to preliminary estimates, a powerful explosion of 200 megatons will occur.

Also, the asteroid 2005 YU 55 is constantly approaching the Earth with a certain periodicity. In November 2011, it flew past our planet at a dangerous close range. And since then it has been considered one of the most dangerous asteroids. The largest asteroid in the belt is Vesta, which is visible to the naked eye from Earth. This is explained by its ability to approach the planet at a distance of only 170 million kilometers. And there are very, very many such potentially dangerous asteroids.

But, despite this, astronomers currently do not see any serious danger to the Earth from asteroids. But, as mentioned earlier, space is unpredictable, so potentially dangerous objects are constantly monitored. For these purposes, especially powerful space telescopes with especially sensitive optics are being developed. Without them, asteroids are quite difficult to see, since they reflect light rather than emit it.

To date, about 1,500 potentially dangerous astronomical objects have been discovered. NASA calls all asteroids and comets that are larger than 100-150 meters in diameter and can approach Earth closer than 7.5 million kilometers. Four of them are assigned a fairly high level of danger on the Palermo scale.

Using the Palermo scale, astronomers calculate how dangerous a particular asteroid approaching our planet is. The indicator is calculated using a special formula: if the result is -2 or less, then the probability of a body colliding with the Earth is practically absent, from -2 to 0 - the situation requires careful observation, from 0 and above - the object is most likely to collide with the planet. There is also the Turin scale, but it is subjective.

During the entire existence of the Palermo scale, only two objects received a value above zero: 89959 2002 NT7 (0.06 points) and 99942 Apophis (1.11 points). After their discovery, astronomers began to closely study the orbits of asteroids. As a result, the possibility of both bodies colliding with the Earth was completely excluded. Additional research almost always leads to a lower hazard rating, as it allows a more detailed study of the object’s trajectory.

Currently, only four asteroids have a hazard rating higher than -2: 2010 GZ60 (-0.81), 29075 1950 DA (-1.42), 101955 Bennu 1999 RQ36 (-1.71) and 410777 2009 FD (-1.78 ). Of course, there are still plenty of objects less than 100 meters in diameter that, in theory, could collide with the Earth, but NASA monitors them less closely - this is an expensive and technically complex undertaking.

Asteroid 2010 GZ60 (diameter – 2000 meters) will approach the Earth 480 times between 2017 and 2116. Some encounters will be quite close - just a few radii of our planet. 29075 1950 DA is slightly smaller (about 1300 meters), but a collision with it will cause catastrophic consequences for humanity - global changes will occur in the biosphere and climate. True, this can only happen in 2880, and even then the probability is very low - approximately 0.33 percent.

101955 Bennu 1999 RQ36 is 490 meters in diameter and will approach Earth 78 times from 2175 to 2199. In the event of a collision with a planet, the force of the explosion will be 1150 megatons of TNT. For comparison: the force of the most powerful explosive device, AN602, was 58 megatons. 410777 2009 FD is considered potentially dangerous until 2198; it will fly closest to Earth in 2185. The diameter of the asteroid is 160 meters.

Municipal educational institution.

Secondary school 109.

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· Find out whether there were cases of asteroids falling on Earth in the past, what consequences this led to;

Working methods: text interpretation, analysis and synthesis, technical modeling.

Introduction.

IN last days The topic of the end of the world in 2012 has become very relevant. One of the television programs talked about asteroids and their possible collision with the Earth. We were interested in the question: do asteroids really pose a real threat to our planet?

We assumed that meteorites had repeatedly fallen on Earth over billions of years, but nothing terrible happened. This means that this threat is fictitious.

But if this is not the case and the threat really exists, then it is necessary to look for ways to protect our planet.

The purpose of our work: suggest ways to prevent asteroids from falling to Earth.

We set it before ourselves tasks:

· Learn what asteroids are;

· Determine by what criteria asteroids are classified;

· Find out which organizations monitor the position of asteroids in the Solar System;

· Find out whether there were cases of meteorites falling on Earth in the past, what consequences this led to;

· Find out whether there is a threat of asteroid impacts;

· Design a device for destruction in the event of the threat of asteroids falling to Earth.

To solve this problem we did the following types works:

· read literary sources that talk about asteroids;

· watched a documentary video about asteroids and celestial bodies of the solar system;

· put forward a hypothesis about the threat of asteroids falling to Earth;

· designed a model of an installation for destroying asteroids in the event of a real threat.

Hypothesis:

The main achievement of our work was a working model, assembled on the basis of a Lego set, designed to destroy celestial bodies that pose a threat to the Earth.

Main part

We carried out our work on the project in several stages.

1. Study the concept of asteroids.

At this stage we have collected large number information about asteroids. We learned what asteroids are. How are they different from meteorites? And what are bolides and other celestial phenomena. (Appendix 1).

2. Classification of asteroids.

At this stage, we have determined that asteroids have different degrees of classification:

By position relative to the orbits of the planets of the solar system;

According to the spectrum of reflected sunlight (Appendix 2).

3. Organizations monitoring the position of asteroids in the Solar System.

At the third stage of the experiment, we found out that the problem of asteroid danger is not new. We found out what exist international organizations who are monitoring asteroids and what measures are being taken to prevent danger. (Appendix 3).

4. Study of cases of asteroids falling to Earth.

At this stage of the work, we learned that there were cases of meteorites falling on planet Earth (Appendix 4). The most famous manifestation of such a threat was the meteorite that fell to Earth about 65 million years ago, which led to a radical change in all life on the planet, putting an end to the era of dinosaurs.

5. Determination: is there a threat of asteroids falling to earth?

We made the assumption that there is a real threat of meteorites falling on planet Earth. We analyzed information about nearby asteroids and the possibility of their collision with the Earth. (Appendix 5).

6. Design a device for destruction in the event of the threat of asteroids falling to Earth.

On final stage In our work, using Lego parts and a globe, we constructed a model of an installation that, in the event of a threat of a collision between planet Earth and other celestial bodies, will be able to prevent a catastrophe (Appendix 6).

Conclusions

At the beginning of our work we put forward the following hypothesis:

Over billions of years, meteorites have repeatedly fallen on Earth, but nothing terrible happened. This means that this threat is fictitious. But if this is not the case and the threat really exists, then it is necessary to look for ways to protect our planet.

Having done work to study the concept of asteroids, meteorites and other celestial bodies and phenomena, we came to the conclusion that there is a real threat of their collision with planet Earth.

But unlike others natural disasters(earthquakes, volcanic eruptions, floods, etc.) fall large bodies to Earth can be pre-calculated and therefore undertaken necessary measures. At the current stage of development of civilization, humanity can already protect itself from the threat of collisions with comets and asteroids. We have designed a similar operating model of an automatic protective installation

However, the technical part of the asteroid-comet hazard problem—preventing a possible collision—seems much more complex and expensive. The global system for protecting the Earth should include means for detecting NEOs, determining the orbits of NEOs and tracking them, a decision-making system for organizing countermeasures in the event of a real threat of collision, as well as means of influencing NEOs and the corresponding rocket and space systems for their prompt delivery. The current level of development of science and technology makes it possible to develop a system for protecting the Earth from collisions with asteroids and comets, although to actually create it, new research and testing is needed, including experiments in space.

References

1. Messengers of the Universe L. Kuznetsov 94-95s. 1980

3. I experience the world I. Gontaruk 294-300s. 1995

4. Erudite astonomy Publishing House World of Books 110-121p. 2007

5. Internet resources

Application. Asteroids. What is it?

Our planet Earth is located in the solar system. The solar system is nature's greatest creation. Life arose in it, intelligence arose, and civilization developed. It consists of eight major planets - Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune and more than 60 of their satellites, among which the most famous is the Earth's satellite - the Moon.

Small planets, of which more than 200 thousand are currently known, rotate within the solar system. Unlike the major planets of the Solar System, most of which have been known since ancient times, the first minor planet Ceres was discovered in the constellation Taurus by the Sicilian astronomer, director of the Palermo Observatory Giuseppe Piazzi on the night of December 31, 1800 to January 1, 1801. Size of this planet was 970x930 km. Between 1802 and 1807 Three more minor planets were discovered - Pallas, Vesta and Juno, whose orbits, like Ceres, lay between Mars and Jupiter. It became clear that they all represented a new class of planets, which, at the suggestion of the English royal astronomer William Herschel, began to be called astroid, since the disks characteristic of large planets could not be distinguished through telescopes.

Asteroid - a small planet-like (star-like) body of the Solar System (minor planet). The largest of them is Ceres. Asteroids vary greatly in size, the smallest of which are no different from dust particles.

Several thousand asteroids are known by their own names. It is believed that there are up to half a million asteroids with a diameter of more than one and a half kilometers. However, the total mass of all asteroids is less than one thousandth the mass of the Earth. Most asteroid orbits are concentrated in the asteroid belt between the orbits of Mars and Jupiter at distances from 2.0 to 3.3 AU. e. from the Sun.

Meteor - this is a short-term phenomenon that occurs in the middle atmosphere of the Earth when small solid cosmic particles enter.

There are two main types of meteors: sporadic, that is, single, and streams. Among the single ones there are fragments of asteroids and comets of the Solar system, “fugitives” from the Moon and Mars, as well as mysterious interstellar hyperbolic small bodies, which came to us from the depths of the Galaxy.

The sources of meteor showers are only asteroids and comets, of which 72% are products of the destruction of asteroids of the Apollo-Anton-Amur group, 19% are the remnants of short-period comet nuclei and 6% are long-period comets. 3% of meteors came from the main asteroid belt, located between the orbits of Mars and Jupiter, which is constantly updated.

Meteors that are brighter than the brightest planets are often called fireballs. Sometimes fireballs are observed brighter than the full moon and extremely rarely those that flare brighter than the sun. Fireballs arise from the largest meteoroids. Among them are many fragments of asteroids, which are denser and stronger than fragments of cometary nuclei. But still, most asteroid meteoroids are destroyed in dense layers of the atmosphere. Some of them fall to the surface as meteorites. Due to the high brightness of the flares, fireballs appear much closer than they really are. Therefore, it is necessary to compare observations of fireballs from different places before organizing a search for meteorites. Astronomers estimate that every day around the Earth, about 12 fireballs end in the fall of meteorites of more than a kilogram.

Application. Classification of asteroids.

Asteroid classification:

By position relative to the orbits of the planets of the solar system.

So in 1898, the first small planet was discovered - Eros, revolving around the Sun at a distance less than Mars. It could approach the Earth's orbit at a distance of about 0.14 AU. e. (au = 149.6 million kilometers - the average distance from the Earth to the Sun), closer than all small planets known at that time.

Such bodies are called near-Earth asteroids (NEAs).

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The Apollo group makes up 66% of NEAs, and its asteroids are the most dangerous to Earth. The largest asteroids in this group are Ganymede - 41 km, Eros - 20 km, Betulia, Ivar and Sisyphus - 8 km.

In addition, there are also those more distant from the Sun, such as the Centaurs.

The Trojans are in orbit around Jupiter.

Asteroids can be classified by the spectrum of reflected sunlight:

Type C asteroids are very dark, carbonaceous. 75% of all asteroids belong to group C.

Grayish siliceous S-type asteroids make up 15% of all asteroids.

M-type (metallic) asteroids and a number of other rare types make up the remaining 10% of all asteroids.

Asteroid classes are associated with known types meteorites. There is much evidence that asteroids and meteorites have similar composition, so asteroids may be the bodies from which meteorites are formed. The darkest asteroids reflect 3 - 4% of the sunlight falling on them, and the brightest reflect up to 40%.

Application. Asteroid observation.

Almost 20 years ago, in July 1981, NASA (USA) held the first Workshop “Collisions of Asteroids and Comets with the Earth: Physical Consequences and Humanity,” at which the problem of the asteroid-comet hazard received “official status.” From then to the present, at least 15 international conferences and meetings devoted to this problem have been held in the USA, Russia, and Italy. Realizing that the primary task of solving this problem is the detection and cataloging of asteroids in the vicinity of the Earth's orbit, astronomers in the United States, Europe, Australia and Japan began to make vigorous efforts to set up and implement appropriate observational programs.

It is obvious that you need to be prepared in advance for a situation where you need to make quick and error-free decisions to save millions and even billions of people. Otherwise, under time pressure, state disunity and other factors, we will not be able to take adequate and effective measures of protection and rescue. In this regard, it would be unforgivably careless not to take effective measures to prevent such events. Moreover, Russia and other technologically developed countries of the world have all the basic technologies to create a Planetary Defense System (PPS) from asteroids and comets.

It should be noted that in a number of countries certain funds have already been allocated and work has begun in this direction. At the University of Arizona (USA), under the leadership of T. Gehrels, a technique for monitoring NEAs has been developed and since the late 80s, observations have been carried out using a 0.9-m telescope with a CCD matrix (2048x2048) at the Kitt Peak National Observatory. The system has proven its effectiveness in practice - about one and a half hundred new NEAs, with sizes up to several meters, have already been discovered. To date, work has been completed to transfer the equipment to the 1.8-m telescope of the same observatory, which will significantly increase the rate of detection of new NEAs. Monitoring of NEAs has begun under two more programs in the United States: at the Lovell Observatory (Flagstaff, Arizona) and in the Hawaiian Islands (a joint NASA-US Air Force program using the 1st Air Force ground-based telescope). In the south of France, at the Côte d'Azur Observatory (Nice), the European NEA Monitoring Program has been launched, in which France, Germany and Sweden are involved. Similar programs are also being staged in Japan.

In this regard, in order to unite the intellectual, technical, financial and other resources available in our country, and then beyond its borders, a number of leading organizations in various industries in Russia and Ukraine (NPO im., Research Center named after, OKB MPEI, NPO "Molniya" ", Research Institute of Mechanics of Moscow State University, MAC "Vympel", State Design Bureau "Yuzhnoye" and a number of others) established Non-profit partnership"Planetary Defense Center" As a program document of the Center, a “Proposal for the creation of the Citadel Planetary Defense System”, developed on the basis of the conceptual design of the Citadel SPZ, was prepared and approved by the members of the Center’s Coordination Council. The project is based on technologies, many of which were developed for military purposes.

Application. The fall of asteroids to the earth and the consequences of collisions.

Geochemical and paleontological data indicate that approximately 65 million years ago, at the turn of the Mesozoic period of the Cretaceous era and the Tertiary period of the Cenozoic era, a celestial body approximately 170-300 km in size collided with the Earth in the northern part of the Yucatan Peninsula (the coast of Mexico). The trace of this collision is a crater called Chicxulub. The power of the explosion is estimated at 100 million megatons! This created a crater with a diameter of 180 km. The crater was formed by the fall of a body with a diameter of 10-15 km. At the same time, a gigantic cloud of dust weighing a total of one million tons was thrown into the atmosphere. The six-month night has arrived on Earth. More than half of the existing plant and animal species died. Perhaps then, as a result of global cooling, dinosaurs became extinct.

According to modern science, in just the last 250 million years there have been nine extinctions of living organisms with an average interval of 30 million years. These disasters can be associated with the fall of large asteroids or comets to Earth. Let us note that it is not only the Earth that suffers from uninvited guests. Spacecraft photographed the surfaces of the Moon, Mars, and Mercury. The craters are clearly visible on them, and they are much better preserved due to the peculiarities of the local climate.

Tunguska phenomenon

In the 20th century, 2 large celestial bodies fell to Russian Earth. Firstly, the Tunguska object, which caused an explosion with a power of 20 megatons at an altitude of 5-8 km above the Earth's surface. To determine the power of the explosion, it is equated in its destructive effect on the environment to the explosion of a hydrogen bomb with a TNT equivalent, in this case 20 megatons of TNT, which is 100 times greater than the energy of the nuclear explosion in Hiroshima. According to modern estimates, the mass of this body could reach from 1 to 5 million tons. An unknown body invaded the earth's atmosphere on June 30, 1908 in the Podkamennaya Tunguska River basin in Siberia.

Since 1927, eight expeditions of Russian scientists successively worked at the site of the fall of the Tunguska phenomenon. It was determined that within a radius of 30 km from the explosion site, all the trees were knocked down by the shock wave. The radiation burn caused a huge forest fire. The explosion was accompanied by a strong sound. Over a vast territory, according to the testimony of residents of the surrounding (very rare in the taiga) villages, unusually light nights were observed. But none of the expeditions found a single piece of the meteorite.

Many scientific and science fiction books have been written on the topic of the Tunguska meteorite. What kind of objects were not attributed to the role of the Tunguska phenomenon: flying saucers and ball lightning and even the famous Halley's comet - as far as the imagination of the authors was enough! But there is no final opinion about the nature of this phenomenon. This mystery of nature is still unsolved.

Russia was lucky: both meteorites fell in a deserted area. If the Tunguska meteorite fell on a large city, then there would be nothing left of the city and its inhabitants.

Of course, comets also collided with the Earth in the distant past. It is collisions with comets, and not asteroids or meteorites, that are credited with the role of gigantic catastrophes of the past, with climate change, the extinction of many species of animals and plants, and the death of developed civilizations of earthlings. Perhaps, 14 thousand years ago our planet met with a smaller comet, but this was quite enough for the legendary Atlantis to disappear from the face of the Earth?

Appendix 5. Possibility of asteroid collisions with the Earth.

In recent years, reports about asteroids approaching the Earth have increasingly appeared on radio, television and in newspapers. This does not mean that there are significantly more of them than before. Modern observational technology allows us to see kilometer-long objects at a considerable distance.

In March 2001, the asteroid "1950 DA", discovered back in 1950, flew at a distance of 7.8 million kilometers from Earth. Its diameter was measured to be 1.2 kilometers. Having calculated the parameters of its orbit, 14 reputable American astronomers published the data in the press. According to them, on Saturday March 16, 2880, this asteroid may collide with the Earth. There will be an explosion with a power of 10 thousand megatons. The probability of a disaster is estimated at 0.33%. But scientists are well aware that it is extremely difficult to accurately calculate the orbit of an asteroid due to unforeseen influences on it from other celestial bodies.

In early 2002, a small asteroid "2001 YB5" with a diameter of 300 meters flew at a distance twice the distance from the Earth to the Moon.

On March 8, 2002, the small planet “2002 EM7,” 50 meters in diameter, approached the Earth at a distance of 460 thousand kilometers. She came to us from the direction of the Sun, and therefore was invisible. It was noticed only a few days after it flew past the Earth.

Reports about new asteroids passing relatively close to the Earth will continue to appear in the press, but this is not the “end of the world,” but ordinary life in our solar system.

Every day, rocks fall to Earth from space. Large stones naturally fall less often than small ones. The smallest specks of dust penetrate tens of kilograms into the Earth every day. Larger pebbles fly through the atmosphere like bright meteors. Rocks and pieces of ice the size of a baseball or smaller, flying through the atmosphere, evaporate completely. As for large rock fragments, up to 100 m in diameter, they pose a significant threat to us, colliding with the Earth approximately once every 1000 years. If dropped into the ocean, an object of this size could cause a tidal wave that would be destructive over long distances. A collision with a massive asteroid more than 1 km across is a much rarer event, occurring once every few million years, but its consequences can be truly catastrophic. Many asteroids go undetected until will approach the Earth. One of these asteroids was discovered in 1998 while studying an image taken by the Hubble Space Telescope (blue dash in the image). Last week, the small 100-meter asteroid 2002 MN was discovered after it passed the Earth, passing inside the orbit of the Moon. The passage of asteroid 2002 MN near Earth is the closest we have seen in the last eight years since the passage of asteroid 1994 XM1. A collision with a large asteroid would not change the Earth's orbit very much. In this case, however, such an amount of dust would arise that the earth's climate would change. This would entail the widespread extinction of so many forms of life that the current extinction of species would seem insignificant.

Currently, about 10 asteroids are known to be approaching our planet. Their diameter is more than 5 km. According to scientists, such celestial bodies can collide with the Earth no more than once every 20 million years.

For the largest representative of the population of asteroids approaching the Earth's orbit, the 40-kilometer Ganymede, the probability of colliding with the Earth in the next 20 million years does not exceed 0.00005 percent. The probability of a collision with the Earth by the 20-kilometer asteroid Eros is estimated for the same period at approximately 2.5%.

The number of asteroids with a diameter of more than 1 km crossing the Earth’s orbit is approaching 500. A fall of such an asteroid onto the Earth can occur on average no more than once every 100 thousand years. The fall of a body 1-2 km in size can already lead to a planetary catastrophe.

In addition, according to available data, the Earth’s orbit is crossed by about 40 active and 800 extinct “small” comets with a nucleus diameter of up to 1 km and 140-270 comets reminiscent of Halley’s comet. These large comets left their imprints on the Earth - 20% of the Earth's large craters owe their existence to them. In general, more than half of all craters on Earth are of cometary origin. And now 20 minicomet cores, each weighing 100 tons, fly into our atmosphere every minute.

Scientists have calculated that the impact energy corresponding to a collision with an asteroid with a diameter of 8 km should lead to a catastrophe on a global scale with shifts earth's crust. In this case, the size of the crater formed on the Earth's surface will be approximately 100 km, and the depth of the crater will be only half the thickness of the earth's crust.

If cosmic body is not an asteroid or meteorite, but is the nucleus of a comet, then the consequences of a collision with the Earth can be even more catastrophic for the biosphere due to the strong dispersion of cometary matter.

The Earth has significantly more opportunities to encounter small celestial objects. Among the asteroids, the orbits of which, as a result of the long-term action of giant planets, can cross the Earth’s orbit, there are at least 200 thousand objects with diameters of about 100 m. Our planet collides with similar bodies at least once every 5 thousand years. Therefore, approximately 20 craters with a diameter of more than 1 km are formed on Earth every 100 thousand years. Small asteroid fragments (meter-sized blocks, stones and dust particles, including those of cometary origin) continuously fall to the Earth.

Application. Creation of a model of a protective installation.

Since there is a possibility of asteroids falling to the earth, we decided to create a model of a protective installation. We have been studying in a robotics club for six months, and we decided to create a model based on the LEGO First Robot RCX construction set.

Thinking about what our installation would consist of, we came to the conclusion that it should consist of two automated devices:

· tracking device for approaching asteroids in the earth;

· a coordination center on the ground that will control the missiles.

The first should be a satellite (ideally several satellites) located in the orbit of our planet and constantly monitoring celestial bodies flying by. When a dangerous asteroid approaches, the satellite must transmit a signal to a coordination center located on the ground.

The center will automatically determine the flight path and launch a rocket with explosives, which will break a large asteroid into smaller ones, thereby preventing a global catastrophe in the event of a collision.

When creating these installations, we used parts of two Lego construction sets: Lego “First Robot” construction sets No. 000, 9796 and LEGO Mindstorms NXT 2.0 construction kit. :

The following main blocks and sensors were also used:

	Microprocessor RCX. Controls the operation of the gun.
	NXT microprocessor. Controls the operation of distance sensors and communicates with the RCX.

	Touch sensor. Used to communicate between RCX and NXT microprocessors.
	Electric motor for pressing the touch sensor.
	Ultrasonic distance sensor (3 pieces) for determining the distance of an asteroid.

Initially, we only used the RCX microprocessor, but it was not possible to connect an ultrasonic distance sensor to it. And without it, determining the distance to an object is very difficult. That's why we also used the NXT microprocessor. Then we realized that one sensor did not allow us to determine from which direction the asteroid was approaching. To eliminate this problem, we decided to use three sensors on three different sides.

After that we had to solve another problem. How to connect these two blocks with each other? And we decided to use a touch sensor. It simplified our work on programming our models, since by the number of touches we were able to determine the firing trajectory and the angle of rotation of the gun.

Another difficulty we faced was the difficulty of creating a satellite. Our constructor does not allow you to create aircraft, and therefore, for clarity, we decided to use a globe to which we attached parts and a motor, thereby simulating a model of a satellite.

Gun model Satellite model

Description of the model's operation.

When the model is turned on, the satellite endlessly rotates three ultrasonic sensor distances. When an object approaches the sensor closer than 20 cm, it triggers and presses the touch sensor one, two or three times, depending on which side the sensor triggered from. After the sensor is triggered, the gun turns in a certain direction, rises to an angle and fires.

The programs used by the devices are as follows:

Satellite program:

Gun operating program:

Of course, our setup is imperfect. We have insufficient quantity knowledge to make more accurate calculations. It was very difficult to program, so Olga Gennadievna helped us.

The Earth can be threatened by objects that approach it at a distance of at least 8 million kilometers and are large enough not to be destroyed when entering the planet’s atmosphere. They pose a danger to our planet.

Until recently, the asteroid Apophis, discovered in 2004, was called the object with the most high probability collisions with the Earth. Such a collision was considered possible in 2036. However, after Apophis passed by our planet in January 2013 at a distance of about 14 million km. NASA specialists have reduced the likelihood of a collision to a minimum. The chances, according to Don Yeomans, head of the Near-Earth Object Laboratory, are less than one in a million.
However, experts have calculated the approximate consequences of the fall of Apophis, whose diameter is about 300 meters and weighs about 27 million tons. So the energy released when a body collides with the Earth’s surface will be 1717 megatons. The strength of the earthquake within a radius of 10 kilometers from the crash site can reach 6.5 on the Richter scale, and the wind speed will be at least 790 m/s. In this case, even fortified objects will be destroyed.

Asteroid 2007 TU24 was discovered on October 11, 2007, and already on January 29, 2008 it flew near our planet at a distance of about 550 thousand km. Thanks to its extraordinary brightness - 12th magnitude - it could be seen even in medium-power telescopes. Such a close passage of a large celestial body from Earth is a rare occurrence. The next time an asteroid of the same size will approach our planet will only be in 2027.
TU24 is a massive celestial body comparable to the size of the University building on Vorobyovy Gory. According to astronomers, the asteroid is potentially dangerous because it crosses the Earth's orbit approximately once every three years. But, at least until 2170, according to experts, it does not threaten the Earth.

Space object 2012 DA14 or Duende belongs to the near-Earth asteroids. Its dimensions are relatively modest - a diameter of about 30 meters, a weight of approximately 40,000 tons. According to scientists, it looks like a giant potato. Immediately after the discovery on February 23, 2012, it was found that science was dealing with an unusual celestial body. The fact is that the asteroid’s orbit is in a 1:1 resonance with the Earth. This means that the period of its revolution around the Sun approximately corresponds to an Earth year.
Duende may remain close to Earth for a long time, but astronomers are not yet ready to predict the behavior of the celestial body in the future. Although, according to current calculations, the probability of Duende colliding with the Earth before February 16, 2020 will not exceed one chance in 14,000.

Immediately after its discovery on December 28, 2005, asteroid YU55 was classified as potentially dangerous. The diameter of the space object reaches 400 meters. It has an elliptical orbit, which indicates the instability of its trajectory and unpredictability of behavior.
In November 2011, the asteroid already alarmed scientific world, flying up to a dangerous distance of 325 thousand kilometers from the Earth - that is, it turned out to be closer than the Moon. Interestingly, the object is completely black and almost invisible in the night sky, for which astronomers nicknamed it “Invisible”. Scientists then seriously feared that a space alien would enter the earth's atmosphere.

An asteroid with such an intriguing name is a long-time acquaintance of earthlings. It was discovered by German astronomer Carl Witt back in 1898 and turned out to be the first near-Earth asteroid discovered. Eros also became the first asteroid to acquire an artificial satellite. We are talking about the NEAR Shoemaker spacecraft, which landed on a celestial body in 2001.
Eros is the largest asteroid in the inner Solar System. Its dimensions are amazing – 33 x 13 x 13 km. The average speed of the giant is 24.36 km/s. The shape of the asteroid is similar to a peanut, which affects the uneven distribution of gravity on it. The impact potential of Eros in the event of a collision with the Earth is simply enormous. According to scientists, the consequences of an asteroid hitting our planet will be more catastrophic than after the fall of Chicxulub, which allegedly caused the extinction of the dinosaurs. The only consolation is that the chances of this happening in the foreseeable future are negligible.

Asteroid 2001 WN5 was discovered on November 20, 2001 and later fell into the category of potentially dangerous objects. First of all, one should be wary of the fact that neither the asteroid itself nor its trajectory have been sufficiently studied. According to preliminary data, its diameter can reach 1.5 kilometers.
On June 26, 2028, the asteroid will once again approach the Earth, and the cosmic body will approach its minimum distance - 250 thousand km. According to scientists, it can be seen through binoculars. This distance is enough to cause satellites to malfunction.

This asteroid was discovered by Russian astronomer Gennady Borisov on September 16, 2013 using a homemade 20 cm telescope. The object was immediately named almost the most dangerous threat among celestial bodies for the Earth. The diameter of the object is about 400 meters.
The asteroid's approach to our planet is expected on August 26, 2032. According to some assumptions, the block will sweep just 4 thousand kilometers from the Earth at a speed of 15 km/s. Scientists have calculated that in the event of a collision with the Earth, the explosion energy will be 2.5 thousand megatons of TNT. For example, the power of the largest thermonuclear bomb detonated in the USSR is 50 megatons.
Today, the probability of an asteroid colliding with the Earth is estimated at approximately 1/63,000. However, with further refinement of the orbit, the figure may either increase or decrease.