Russian geophysicists have modeled the collision of Earth with an asteroid
If earlier to the possibility of cosmic catastrophe were defined as “academic”, now modern techniques allow us to consider the threat from the practical side. Geophysicists have built a model of the possible events that will happen on Earth if it drops an asteroid the size of one kilometer in diameter.
Geophysics and astronomers from the Institute of dynamics of geospheres Russian Academy of Sciences and the Moscow physical-technical Institute built a model of the possible events that will happen on Earth if it drops an asteroid with a diameter up to one kilometer.
If earlier to the possibility of cosmic catastrophe were defined as “academic”, but now modern methods of computational Geophysics allow us to consider the collision of an asteroid with the Earth as a complex scientific problem and the practical point of view. We will remind that quite recently, experts have compiled a list of the most dangerous effects of the fall of the asteroid.
In the new work by Russian scientists conducted a numerical simulation of the flight through the atmosphere and hitting the surface of the Earth stone cosmic body with a diameter of 300 meters c kinetic energy of 1000 megatons, which corresponds to the parameters of the Apophis, the probability of collision with the Ground exists.
As explained by the authors, the asteroid could enter the atmosphere at different angles: 90° (vertical impact), 45° and 30°.
Modeling of the processes accompanying the fall of cosmic bodies on the Earth, was carried out in several stages by solving three-dimensional equations of hydrodynamics and equations of radiative transfer. As threat factors were considered by the air shock wave, the emission from the crater thermal radiation and ionospheric perturbations”Olga Populatlon research group
Calculations of overpressure and wind velocity at the Earth’s surface showed that the diameter of the zone of destruction of the weakest designs can reach 700-1000 kilometers, with a decrease of the angle of inclination of the trajectory to the surface will lead to a significant increase in the area impacted by the shock wave. The size of a zone with excess pressure of more than 20-35 kPa will be almost 400 kilometers.
Meanwhile brick wall with a thickness of 24-36 cm begin to collapse at a pressure of 20 kPa, and the walls of concrete blocks with a thickness of 24-36 cm are completely destroyed at a gauge pressure of 35 kPa.
Also simulations have shown that perturbations of the ionosphere will be global in nature and will last for several hours. As a result of electromagnetic disturbances disrupted the operation of the means of communication around the world will start to make mistakes satellite navigation.
At distances of several thousand kilometers at altitudes of over 100 kilometers perturbations the density of air will amount to tens of percent. Created the wind, the speed of which will reach several hundred meters per second.
Just 10 minutes after the collision of an asteroid with the Earth the area of the drop will cover a dust cloud with a radius of up to 800 kilometers.
In clear weather the size of the region where under the influence of thermal heating can ignite trees, reaching 200 kilometers, and the area of individual fires, light up where flammable materials may be twice. In the Central region of a very strong thermal lesions with a size of about 100 kilometers will light designs, a roof, clothing. Dangerous region increases with decreasing the inclination angle of the trajectory, and the heating effect may be felt by people at distances up to 250-400 km from the crater.
First of all, such models are built to tackle the important task of creating an effective system to prevent the consequences of such catastrophes, the authors note. For clarity, they modeled the fall of an asteroid in the center of Moscow.
In the case of such a catastrophe, which forms a crater, inside of which would be the whole historical part of the capital bounded by the Garden ring.
Almost all areas inside the Ring road all living things will be killed by the shock wave. The whole territory of the Moscow region will be engulfed in massive fires.
The destruction caused by such falling of the Chelyabinsk meteorite, will be observed throughout the Central district of Russia. Strong ionospheric disturbances, apparently, can cause serious violations of telecommunications, will be visible throughout Europe. And finally, the abnormal weather phenomena may be observed worldwide for several years after the fall of the asteroid.
In the study, together with the Institute of astronomy and research Institute on problems of civil defense and emergency situations of EMERCOM of Russia specialists have already prepared a strategy to counter the effects of the disaster. The same theme, we will remind, not so long ago, were discussed at the meeting of the American geophysical Union.
Theoretically, to prevent the fall of an asteroid on our planet possible by changing the trajectory of its flight. Space mission, in which scientists try to change the orbit of a celestial body, starts in 2020.