Asteroid danger: causes, methods of protection. The most dangerous asteroids - a collision with Earth can destroy the planet

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. Experts back in the 1960s 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 dangerously close to the Earth, and even the slightest disruption to their trajectory 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 rapidly, 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 argue that once every 500 thousand years the planet experiences a 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 of average size. 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 asteroid's approach to Earth in 2029 will change its orbit, making predictions about its subsequent trajectory 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. It flew past our planet in November 2011 at a dangerously close distance. And since then it has been considered one of the most dangerous asteroids. The largest asteroid in the belt is Vesta, which is visible from Earth with the naked eye. 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 threat 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.

Sometimes asteroids (or other space objects) crash into the Earth, leaving craters on continents, fall into the ocean, or explode in the atmosphere.

Scientists call this event a collision with Earth. Most asteroids are usually small and do not cause any problems. But from time to time catastrophic falls occur.

When will the next big clash be?

First of all, we must be clear about what we mean by “big impact.” Typical definition: large enough to cause a regional or planetary catastrophe unprecedented in human history in the form of a series of earthquakes, a “nuclear” winter, or a devastating tsunami.

If we knew exactly the position, speed, shape and size of every moderately large object in the solar system, we could use physics and mathematics and predict simply and effectively where and when things might happen! Unfortunately, humanity has not yet cataloged all moderately large (or similar) objects, since they are not all yet discovered and new asteroids and comets continue to be discovered.

Today, for all the large asteroids that we know about, the best we can do is determine the probability of impact with Earth and estimate the amount of possible damage to the planet from this impact. To assess the danger of an object, the so-called Turin Scale or Torino scale was invented - a table showing the degree of danger emanating from a certain celestial object (for example, an asteroid). The Turin Scale uses values from 0 to 10. 0 (zero) means that the probability of an object colliding with the Earth is so small that it falls into observational error. 10 means that a collision is inevitable, and it will lead to global consequences. The magnitude of the danger according to the Turin Scale is determined based on the mathematical probability of a collision and the kinetic energy of the collision.

So, what large asteroids do we know are most likely to crash into Earth in the near future?

Current leaders in the list of the most dangerous asteroids

There is a table where you can see this - Sentry Risk Table, led by NASA. Look in the Torino column (Turin Scale) for objects of danger level 1 or higher. At the time of this writing, only two of these asteroids exist, each with a level 1 Torino scale:

Asteroid 2007 VK184

Asteroid 2013 TV135

1st hazard class according to the Turin Scale

1st class is the lowest on the Turin Scale. This means that there is virtually no risk of the Earth colliding with the most dangerous asteroids. But it is still non-zero. However, further observations may virtually eliminate the risk of collision altogether. Thus, in January 2013, NASA completely ruled out the possibility of a collision with the Earth by the asteroid Apophis, which for a long time was the leader of the asteroid danger and had (initially) level 4 on the Turin scale.

Asteroid 2007 VK184

Asteroid 2007 VK184 was discovered by the Catalina Sky Survey in 2007 and has a 1:3000 chance of impacting Earth. This is the highest probability of a collision with Earth for all asteroids known today. If a collision with it occurs, the asteroid (most likely) will break up in the atmosphere into several separate parts. However, these individual pieces will still be quite large and could cause widespread destruction and lead to numerous casualties if an asteroid falls in densely populated areas. For comparison, the fall of the Tunguska asteroid (or comet) in 1908 was caused by an object with dimensions of 30-50 meters. This size was enough to produce an air explosion of 40-50 megatons. The power of the explosion of the Chelyabinsk meteorite ranged from 0.4 to 1.5 megatons with an object size of 17 meters and a mass of 10 thousand tons.

Asteroid 2013 TV135

Asteroid 2013 TV135. Photo: The Virtual Telescope Project 2.0

The 440-meter asteroid 2013 TV135 was discovered in the current year 2013 and as a result of observations, the probability of its collision with the Earth in 2032 increased from 1:63000 to 1:9009. The impact probability is less than that of Asteroid 2007 VK184, but this probability is still quite high, given the fact that the consequences of Asteroid 2013 TV135 hitting Earth could cause destruction in a radius of 260,000 square kilometers and cause significant changes in the planet's climate in the future.

Predicting collisions by analyzing Earth's history

Vredefort Crater is the largest and oldest known meteorite crater, located in South Africa.

There is another way to calculate the probability of a large object colliding with the Earth - this is to study everything we know about past events:

Objects with sizes ranging from 5-10 meters in width.
Impact Earth about once a year and release more energy than the atomic bomb dropped on Hiroshima. They usually go undetected because most of the Earth's surface is uninhabited and the energy is most often released high in the planet's atmosphere.

Objects measuring 50 meters wide.
They collide with the Earth approximately once every 1000 years (the Tunguska meteorite is just such a case).

Objects measuring 1000 meters wide.
Collide with Earth approximately once every 500,000 years.

Objects measuring 5000 meters wide.
Collide with Earth approximately once every 10 million years.

Even larger objects also crashed into the Earth.
The object that hit Earth 65 million years ago, blamed (at least in part) for the extinction of the dinosaurs, was about 10,000 meters wide and caused an explosion with a yield of 100,000 gigatons. After the fall of this giant asteroid (or comet), 16% of existing families of marine animals and 18% of families of land vertebrates disappeared. There is an assumption that the tsunami caused by this catastrophic explosion reached 100 meters in height. And the dust cloud from the explosion blocked the sun for several years. The sediments caused by the explosion at the end of the Cretaceous period formed a layer of sediment with high levels of iridium and osmium (elements of extraterrestrial origin), which, according to scientists, could not have occurred naturally on Earth.

Instead of a conclusion

Another place where you can look at data on the most dangerous asteroids for Earth is the list NEODyS "Risk list", which is led by a European consortium.

Both the list and the NASA table and the European “Risk list” demonstrate that, at least in the near future, nothing threatens humanity, since astronomers do not know of sufficiently large space objects with a high probability of colliding with the Earth. In addition, based on historical facts, it can be predicted that in this and the next century the probability of a planet colliding with a truly large object is negligibly small.

However, it should be noted that both the American and European lists of dangerous objects do not include objects with large, highly elliptical orbits (such as many comets). They also do not include objects with hyperbolic orbits—objects that fly through the solar system and disappear into space forever, never to return.

In addition, the lists cover only objects known in near-Earth space and, naturally, do not include yet unknown (undetected) objects. According to astronomers, there are at least 500,000 of them. For comparison: at the moment, data has been collected on only 10 thousand asteroids. So danger can come at any moment - from where they were not expected, and a hitherto unknown celestial object can forever change life on our Earth.

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 collapse when entering the planet’s atmosphere. They pose a danger to our planet.

1. Apophis

Until recently, the asteroid Apophis, discovered in 2004, was called the object with the highest probability of colliding with the Earth. Such a collision was considered possible in 2036. However, after Apophis passed by our planet in January 2013 at a distance of about 14 million km. NASA specialists have reduced the likelihood of a collision to a minimum. The chances, according to Don Yeomans, head of the Near-Earth Object Laboratory, are less than one in a million.

However, experts have calculated the approximate consequences of the fall of Apophis, whose diameter is about 300 meters and weighs about 27 million tons. So the energy released when a body collides with the 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 the scientific world by flying up to a dangerous distance of 325 thousand kilometers from the Earth - that is, it turned out to be closer than the Moon. Interestingly, the object is completely black and almost invisible in the night sky, for which astronomers nicknamed it “Invisible”. Scientists then seriously feared that a space alien would enter the earth's atmosphere.

An asteroid with such an intriguing name is a long-time acquaintance of earthlings. It was discovered by German astronomer Carl Witt back in 1898 and turned out to be the first near-Earth asteroid discovered. Eros also became the first asteroid to acquire an artificial satellite. We are talking about the NEAR Shoemaker spacecraft, which landed on a celestial body in 2001.

Eros is the largest asteroid in the inner Solar System. Its dimensions are amazing – 33 x 13 x 13 km. The average speed of the giant is 24.36 km/s. The shape of the asteroid is similar to a peanut, which affects the uneven distribution of gravity on it. The impact potential of Eros in the event of a collision with the Earth is simply enormous. According to scientists, the consequences of an asteroid hitting our planet will be more catastrophic than after the fall of Chicxulub, which allegedly caused the extinction of the dinosaurs. The only consolation is that the chances of this happening in the foreseeable future are negligible.

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

This asteroid was discovered by Russian astronomer Gennady Borisov on September 16, 2013 using a homemade 20 cm telescope. The object was immediately called perhaps the most dangerous threat among celestial bodies to the Earth. The diameter of the object is about 400 meters.
The asteroid's approach to our planet is expected on August 26, 2032.

According to some assumptions, the block will sweep just 4 thousand kilometers from the Earth at a speed of 15 km/s. Scientists have calculated that in the event of a collision with the Earth, the explosion energy will be 2.5 thousand megatons of TNT. For example, the power of the largest thermonuclear bomb detonated in the USSR is 50 megatons.
Today, the probability of an asteroid colliding with the Earth is estimated at approximately 1/63,000. However, with further refinement of the orbit, the figure may either increase or decrease.