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Where did the Chelyabinsk meteorite fall on the map. Where did the meteorite fall in Chelyabinsk? Photos and details from the meteorite impact site. Life after the meteorite fall |
Keywords HEAVENLY BODY / ASTEROID / METEORITE / HELIOCENTRIC ORBIT / TRAJECTORY OF MOVEMENT/ EARTH'S ATMOSPHERE / CELESTIAL BODY / ASTEROID / METEORITE / HELIOCENTRIC ORBIT / TRAJECTORY OF MOTION / AIR BLAST / BLAST WAVE / IMPACT AREAannotation scientific article on Earth sciences and related ecological sciences, author of scientific work - Bondarenko Yury Sergeevich, Medvedev Yury DmitrievichA technique has been developed to determine trajectory celestial body in the Earth's atmosphere, parameters heliocentric orbit body before it enters the atmosphere, as well as assess the main factors of damage by a shock wave. The technique provides for the study of several scenarios for the development of events due to the passage of an object in the Earth's atmosphere. If the object passed through the atmosphere without colliding with the Earth, the moments of entry and exit of the body from the Earth's atmosphere are determined. An object can collide with the Earth without being destroyed. In this case, the differential equations are integrated until the celestial body reaches the Earth's surface. It was believed that an object burns up in the atmosphere if its radius becomes less than 1 cm. Separately, the case was considered when the object is destroyed during the movement, and only fragments reach the Earth's surface. The developed technique was implemented in a software-computer complex. One of the advantages of the complex is the ability to save calculation results in a .kml file, which allows displaying three-dimensional geospatial data in the Google Earth program, as well as on two-dimensional Google maps. In our case, this is the flight path and its projection on the Earth's surface, the places of destruction, explosion and fall of the meteorite, the area of fragments falling and shock wave damage, as well as other useful information. The efficiency of the software and computing system was tested on the motion of the asteroid 2008 TC3 and the Chelyabinsk meteorite. It was shown that the orbits of the 2008 TC3 and Chelyabinsk meteorites before entering the atmosphere turned out to be close to the orbits obtained by other authors, and the parameters air bursts coincide with the original data within their accuracy. The resulting areas of fall of fragments of these meteorites are only a few kilometers from the discovered fragments. The zones of destruction as a result of the action of an air shock wave in the case of the Chelyabinsk meteorite coincide with real data. Related Topics scientific papers on Earth sciences and related ecological sciences, author of scientific work - Bondarenko Yury Sergeevich, Medvedev Yury Dmitrievich
Determination of the trajectory of motion of celestial bodies in the Earth""s atmosphereThe authors have developed and realized the method, allowing to determine the trajectory of motion of celestial bodies in the Earth's atmosphere, to determine the parameters of heliocentric orbit of celestial bodies prior to its entry into the atmosphere, as well as to estimate major factors of damage due to the blast wave . The method researches several scenarios due to the passage of the object in the Earth's atmosphere. In case the object passed through the atmosphere, without colliding with the Earth, the moments of an entrance and exit of a body from the Earth’s atmosphere are determined. The object can collide with the Earth without breakup. In this case, the differential equations are integrated until the celestial body reaches the Earth's surface. It was assumed that the object burns in the atmosphere, if its radius becomes less than 1 cm. The case when object breaks up during the motion and only the fragments reach the Earth's surface was considered separately. The developed method has been implemented in the software package. One of the advantages of the package is the ability to save the results of calculations in the.kml format, allowing to display threedimensional geospatial data in the “Google Earth” as well as two-dimensional data in “Google” maps. In our case these data are the flight trajectory and its projection to the Earth’s surface, the places of meteorite break up and air burst, the impact areas of the fragments, the overpressure areas due the blast wave , as well as other useful information. Using this method the motion of Chelyabinsk and 2008 TC3 meteorites were simulated. It was shown that heliocentric orbital elements of the Chelyabinsk and 2008 TC3 meteorites before entering the Earth 's atmosphere calculated using the developed software are close to the parameters obtained by other authors, the trajectory parameters are in good agreement with the initial data within their accuracy . Estimated impact areas of meteorites fragments are only in a few kilometers from the recovered one. The overpressure areas due to the blast wave in case of “Chelyabinsk” meteorite coincide with the real data. The text of the scientific work on the topic "Determination of the trajectory of the movement of celestial bodies in the Earth's atmosphere"UDC 521.35; 523.628.4 Bulletin of SibGAU 2014. No. 4(56). pp. 16-24 DETERMINATION OF THE TRAJECTORY OF MOVEMENT OF CELESTIAL BODIES IN THE EARTH'S ATMOSPHERE Yu. S. Bondarenko, Yu. D. Medvedev Institute of Applied Astronomy of the Russian Academy of Sciences Russian Federation, 191187, St. Petersburg, nab. Kutuzova, 10 [email protected] A technique has been developed that makes it possible to determine the trajectory of a celestial body in the Earth's atmosphere, the parameters of the body's heliocentric orbit prior to its entry into the atmosphere, and also to evaluate the main factors of damage by a shock wave. The technique provides for the study of several options for the development of events due to the passage of an object in the Earth's atmosphere. If the object passed through the atmosphere without colliding with the Earth, the moments of entry and exit of the body from the Earth's atmosphere are determined. An object can collide with the Earth without being destroyed. In this case, the differential equations are integrated until the celestial body reaches the Earth's surface. It was believed that an object burns up in the atmosphere if its radius becomes less than 1 cm. The case was considered separately when the object is destroyed during the movement, and only fragments reach the Earth's surface. The developed technique was implemented in a software-computer complex. One of the advantages of the complex is the ability to save calculation results in a .kml file, which allows displaying three-dimensional geospatial data in the Google Earth program, as well as on two-dimensional Google maps. In our case, this is the flight path and its projection on the Earth's surface, the places of destruction, explosion and fall of the meteorite, the area of fragments falling and shock wave damage, as well as other useful information. The efficiency of the software and computing system was tested on the motion of the asteroid 2008 TC3 and the Chelyabinsk meteorite. It was shown that the orbits of the 2008 TC3 and Chelyabinsk meteorites before entering the atmosphere turned out to be close to the orbits obtained by other authors, and the parameters of air explosions coincide with the original data within their accuracy. The resulting areas of fall of fragments of these meteorites are only a few kilometers from the discovered fragments. The zones of destruction as a result of the action of an air shock wave in the case of the Chelyabinsk meteorite coincide with real data. Key words: celestial body, asteroid, meteorite, heliocentric orbit, motion trajectory, Earth's atmosphere, air burst, shock wave, impact area. Vestnik SibGAU 2014, no. 4(56), P. 16-24 DETERMINATION OF THE TRAJECTORY OF MOTION OF CELESTIAL BODIES IN THE EARTH'S ATMOSPHERE Yu. S. Bondarenko, Yu. D. Medvedev Institute of Applied Astronomy of Russian Academy of Sciences 10, Kutuzova nab., St. Petersburg, 191187, Russian Federation [email protected] The authors have developed and realized the method, allowing to determine the trajectory of motion of celestial bodies in the Earth's atmosphere, to determine the parameters of heliocentric orbit of celestial bodies prior to its entry into the atmosphere, as well as to estimate major factors of damage due to the blast wave. The method researches several scenarios due to the passage of the object in the Earth's atmosphere. In case the object passed through the atmosphere, without colliding with the Earth, the moments of an entrance and exit of a body from the Earth's atmosphere are determined. The object can collide with the Earth without breakup. In this case, the differential equations are integrated until the celestial body reaches the Earth's surface. It was assumed that the object burns in the atmosphere, if its radius becomes less than 1 cm. The case when object breaks up during the motion and only the fragments reach the Earth's surface was considered separately. The developed method has been implemented in the software package. One of the advantages of the package is the ability to save the results of calculations in the .kml format, allowing to display three-dimensional geospatial data in the "Google Earth" as well as two-dimensional data in "Google" maps. In our case these data are the flight trajectory and its projection to the Earth"s surface, the places of meteorite break up and air burst, the impact areas of the fragments, the overpressure areas due the blast wave, as well as other useful information. Using this method the motion of Chelyabinsk and 2008 TC3 meteorites were simulated. It was shown that heliocentric orbital elements of the Chelyabinsk and 2008 TC3 meteorites before entering the Earth's atmosphere calculated using the developed software are close to the parameters obtained by other authors, the trajectory parameters are in good agreement with the initial data within their accuracy The overpressure areas due to the blast wave in case of "Chelyabinsk" meteorite coincide with the real data. Keywords: celestial body, asteroid, meteorite, heliocentric orbit, trajectory of motion, Earth's atmosphere, air blast, blast wave, impact area. Introduction. The main disturbing factors in the motion of small bodies in the solar system are the attraction of large planets, which in most cases are considered as material points. However, in the case of a close approach or collision of the object under study with the Earth, it is necessary to take into account such factors as the influence of non-sphericity, the perturbation exerted by the Earth's atmosphere, the mass, composition and shape of the body itself, which presents a certain difficulty for researchers. In this regard, there is a need to develop a technique that allows one to make a fairly accurate estimate of the trajectory of a body when it moves both near and in the Earth's atmosphere. dynamic model. In the developed dynamic model, if the object under study moves outside the earth's atmosphere, the equations of motion are given in a rectangular heliocentric coordinate system and have the form where " - gravitational acceleration from the Sun; W2" - perturbing accelerations determined by the attraction of the object under study by the planets; W," - relativistic corrections. If the body entered the Earth's atmosphere, then there is a transition to the geocentric coordinate system, and the equations of motion change. They add terms that take into account the compression of the Earth and the resistance of the atmosphere. A differential equation is also added that describes the change in the size of an object due to its deceleration in the atmosphere: 7 = W + W2 + W3; I = VI where W - gravitational acceleration from the Earth, taking into account compression; G2 - gravitational perturbations from the Sun and planets of the Solar system; W, - atmospheric resistance; V is the rate at which the object's size changes. The perturbing acceleration W, which takes into account the resistance of the atmosphere, is given in the form W = -1 Cd рУ ( speed; the ratio of the midsection to the mass of the object m characterizes the windage. For convenience, the letter P denotes the pressure exerted by air on the body, and the letter A denotes air resistance. Assuming that part of the energy arising from atmospheric resistance goes to heating and evaporation of matter from the surface of the body, and the object itself has and retains a spherical shape as a result of evaporation, the rate of change in the body radius will be determined by the following expression: where y is the amount of energy spent on the sublimation of matter; I is the radius of the object; K is the heat required to vaporize 1 kg of a substance. Possible development of events. The technique provides for the study of several options for the development of events due to the passage of an object in the Earth's atmosphere. If the object passed through the atmosphere without colliding with the Earth, the moments of entry and exit of the body from the Earth's atmosphere are determined. An object can collide with the Earth without being destroyed. In this case, the differential equations are integrated until the celestial body reaches the Earth's surface. It was believed that an object burns up in the atmosphere if its radius R becomes less than 1 cm. The case was considered separately when the object is destroyed during its movement, and only fragments reach the Earth's surface. The destruction of the body occurs when the air pressure on the body P reaches the critical value Рmax. The values of critical pressure for various materials of the object under study are presented in Table. one . Depending on the given density, the critical pressure values are determined from Table. 1 by interpolation. Table 1 Critical pressure values for various materials Material Density, kg/m3 Pmax; Pa Porous rock 1500 105 Hard Rock 3600 10" Iron 8000 108 where Sp is the coefficient of air resistance; pa - air density; u is the object's velocity vector relative to the Earth's atmosphere; and - vector modulus Having reached the critical pressure, the body is destroyed, however, for some time the fragments of the body move as a single whole, moving away from each other at a speed bodies at the moment of destruction; p is the density of the body. After destruction, the rate of resizing object V in the system is taken equal to V. Due to the difference in pressures on the front and rear surfaces, the fragmented body, as it were, expands perpendicular to the motion trajectory until the ratio of the current radius to the radius of the body at the moment of destruction R(t)/R reaches the specified limit. Estimates of this value by different authors vary from 2 to 10. In the developed dynamic model, it is considered that an air explosion occurs at the moment when the value of R(t) = 5R, provided that the body has not reached the Earth's surface by this moment. From this moment, it is considered that the fragments begin to move along independent trajectories, and the consequence of their rapid deceleration is a shock wave. The parameter of the shock wave, which determines its effect on various objects, is the maximum overpressure at the front Apm. On the basis of experimental data for a spherical shock wave, an empirical dependence 1 2 Apm = 0.084 - + 0.27 U- + 0.7 E Fm l l2 l3 where E is the energy of the explosion, measured in kg of TNT equivalent; l - distance from the explosion center, m; excess pressure at the front of the shock wave Apm is measured in MPa. This formula is valid for high power explosions: E > 100 kg TNT in the range 0.01< Apm < 1 МПа. The direct impact of excess pressure at the front of the shock wave leads to partial or complete destruction of buildings, structures and other objects. Depending on the magnitude of the excess pressure, various destruction zones are distinguished, the values of which are presented in Table. 2. The lesion on flat terrain is conditionally limited to a radius with an overpressure of 10 kPa (0.1 kgf/cm). The energy of an air explosion is determined by the amount of energy released during deceleration of a collapsing body, according to the formula E = l-tiT, 2 where m is the mass of the body at the moment of destruction; n is the fraction of energy released almost instantaneously during deceleration of small fragments. Thus, knowing the energy and height of the explosion, the dimensions of the destruction zones are found. table 2 Destruction under the influence of a shock wave Destruction zones Apm, kPa Glass strength threshold 1 10% glass broken 2 Minor damage to buildings 5 Partial destruction 10 Medium destruction 20 Strong Destruction 30 Complete destruction 50 destruction of the object into fragments. To estimate the area of impact, the developed method integrates together the movement of 4 fragments, which fly apart in opposite directions in a plane perpendicular to the velocity vector of the body at the moment of destruction um with velocities V = -\[p~1rot. These directions are shown in fig. 1. In this case, the velocity vectors of each of the four fragments u, uE, and are given by the formulas Tl Yu - - Tl Yu X°T uW = uT + V-; uN \u003d uT + V--g Suppose that during the movement of the body in the Earth's atmosphere at some point in time T, uE = uT - VuW ; uS = uT - VuN, where rä = uT x ¥T ; ¥T - body position vector at the moment of destruction. The fragment radius is taken equal to Rf = RT/n , where n is the number of fragments; RT - radius object at the time of destruction. The coordinates of the fall fragments indicated in fig. 1 points W, E, N and S are calculated taking into account the parameters of precession and nutation of the Earth's axis, and the area of incidence is approximated by an ellipse passing through these points. The developed technique was implemented in a software-computer complex. One of the advantages of the complex is the ability to save the calculation results in a .kml file, which allows you to display three-dimensional geospatial data in the Google Earth program And also on two-dimensional Google maps. In our case, this is the flight path and its projection on the Earth's surface, the places of destruction, explosion and fall of the meteorite, the area of fragments falling and shock wave damage, as well as other useful information. The efficiency of the software and computing complex was tested on the motion of the asteroid 2008 TC3 and the Chelyabinsk meteorite. Asteroid 2008 TC3. Asteroid 2008 TC3 was discovered on the morning of October 6, 2008 at Mount Lemmon Observatory. Operational calculations of the preliminary orbit showed that this asteroid should collide with the Earth in the next 24 hours. It was the first celestial body discovered before entering the Earth's atmosphere. Its diameter was estimated in the range from 2 to 5 m. On October 7, the meteorite was destroyed when it fell in the atmosphere over the desert territory of Sudan at an altitude of 37 km with coordinates of 20.8 ° N. sh. and 32.2° E. d. More than 600 asteroid fragments with a total mass of 10.7 kg were later found. At the first stage, using the method of determining orbits based on the enumeration of orbital planes , the elements of the heliocentric orbit were obtained (Table 3), which represent 589 positional observations of the asteroid 2008 TC3 with a root-mean-square error c = 2.0"" for epoch 2454746.5 JD (7 October 2008). These elements define the so-called nominal orbit, i.e., satisfying the conditions of the least squares method. For comparison in table. Figure 3 also shows orbital elements obtained by the Jet Propulsion Laboratory (JPL). Further, using the obtained elements of the orbit, the motion of the asteroid 2008 TC3 was simulated until the moment of its collision with the Earth. In the adopted model, the equations of motion take into account gravitational perturbations from all the major planets, the Moon and Pluto. The coordinates of the perturbing planets were calculated from the numerical ephemeris EPM. Numerical integration of the equations of motion was performed by the 4th order Runge-Kutta method with automatic step selection according to the velocity value. The air density was calculated from the US 1976 Standard Atmosphere Tables, in which the atmosphere is divided into seven consecutive layers with a linear dependence of temperature on height. The Earth's surface was approximated by an ellipsoid of revolution. Assuming that the object was spherical, the drag coefficient air Cn was taken equal to 2 . The amount of energy spent on the sublimation of matter y was taken equal to 10-3 for the main body, and 10-2 for fragments. It was also believed that 600 cal/g is needed to evaporate 1 kg of the substance of the asteroid 2008 TC3. The results of simulation of the motion of the asteroid 2008 TC3 in the Earth's atmosphere are shown in Figs. 2, which shows a satellite image of the area, on which the black line shows the trajectory of the meteorite, obtained from the elements of the nominal orbit, and the white line shows its projection onto the Earth's surface. The places of the beginning of the destruction and explosion of the meteorite are designated by the letters A and B, respectively, and their parameters in comparison with satellite data are given in Table. 4. The numbers mark the places of the discovered fragments of the meteorite, and their masses and coordinates are given in Table. 5. Rice. 1. Determining the area of falling fragments IPA 330.7502 234.4474 194.1011 2.5416 0.311995 0.658783 CXR 330.7541 234.4490 194.1011 2.5422 0.312065 0.658707 Table 4 Parameters of the places where the destruction and explosion of the asteroid 2008 TSZ began IPA parameter Satellite data (KABA/KHR, 2008) Destruction Explosion Altitude, km 36.9 35.2 37 Time, IT 02:45:51 02:45:51 02:45:45 Latitude, ° with. sh. 20.72 20.71 20.8 Longitude, ° in. 32.15 32.19 32.2 Table 5 Parameters of found fragments of asteroid 2008 TZ Parameter 1 2 3 4 5 6 7 Weight, g 4.412 78.201 65.733 141.842 378.710 259.860 303.690 Latitude, ° with. sh. 20.77 20.74 20.74 20.70 20.68 20.70 20.70 Longitude, ° in. 32.29 32.33 32.36 32.49 32.50 32.50 32.52 Rice. 2. Simulation results of the motion of the 2008 TC3 meteorite in the Earth's atmosphere From Table. Figure 5 shows that the masses of the detected fragments do not exceed a kilogram, therefore, after the explosion of the meteorite, the motion of fragments with masses in the range from 100 to 700 g was simulated. to files. The figure shows the probable regions of impact of fragments of various masses, obtained from the nominal orbit and its two variations. The letters A and B denote the regions where the fragments with the smallest and largest masses fell out, respectively. On fig. 2 shows a good agreement between the results of the assessment of the impact areas with the found fragments, and small deviations can be explained, for example, by the effect of wind. Table data. 4 also indicate a good agreement between the simulation results and satellite data. Meteorite "Chelyabinsk". On the morning of February 15, 2013, a bright flash was observed in the sky over Chelyabinsk, which was caused by a relatively small asteroid approximately 17-20 m in diameter, which entered the Earth's atmosphere at high speed and at a small angle. At that moment, a huge amount of energy was released, and the body itself collapsed into many parts of different sizes, which fell to the ground. Since this event took place over a populous city, it differs from similar events in the number of eyewitness accounts. It was recorded by a large number of video recorders and video cameras. In addition, meteorological satellites MyeoBa! 9 and MeleoBa1 10 were able to photograph the condensation trail from the passage of a meteorite in the Earth's atmosphere, and from the bottom of Lake Chebarkul a fragment of a meteorite about a meter in size and weighing approximately 600 kg was raised. To model the movement of the meteorite, the most accurate data to date were used as the initial parameters, which were obtained by equipment installed on geostationary satellites operating in the interests of the US Department of Defense and the US Department of Energy. This equipment makes it possible to track nuclear air explosions, as well as to measure the luminosity curves of fireballs burning up in the atmosphere. According to these data, the moment of maximum brightness occurred on February 15, 2013 at 03:20:33 GMT at an altitude of 23.3 km with coordinates of 54.8° N. sh. and 61.1° E. e. The speed of the object at the moment of maximum brightness was 18.6 km / s, and the released energy was 440 Kg in TNT equivalent. The trajectory azimuth and inclination, obtained by Colombian astronomers from numerous records from video recorders and surveillance cameras, were taken to be 285 ± 2° and 15.8 ± 0.3°, respectively. The found remains of a meteorite indicate that it was an ordinary chondrite with a density of approximately 3.6 g / cm3. The diameter of the object before entering the atmosphere was taken to be 18 m. These parameters were used to calculate the elements of the object's heliocentric orbit prior to its entry into the atmosphere at epoch 2456336.5 AR (February 13, 2013). These elements, in comparison with the results of other authors, are presented in Table. 6 in the first line. Table 6 Comparison of the parameters of the resulting heliocentric orbit IPA 0.70 0.56 100.90 326.46 4.27 1.60 7u1^a 0.71 0.48 97.98 326.47 4.31 1.37 1Аu 3423 0.77 0.5 109.7 326.41 3.6 1.55 INASAN 0.74 0.58 108.3 326.44 4.93 1.76 KhNU 0.65 0.65 97.2 326.42 12.06 1.83 Rice. 3. Heliocentric orbit of the Chelyabinsk meteorite Rice. 4. Simulation results of the motion of the Chelyabinsk meteorite in the Earth's atmosphere Rice. 5. Areas of falling fragments of the meteorite "Chelyabinsk" On fig. 3 shows the heliocentric orbit of the Chelyabinsk meteorite in the plane of the ecliptic according to the calculated elements, obtained using the NLBU software complex. As can be seen from fig. 3, the asteroid's orbit reaches the orbit of Venus at perihelion and the asteroid belt at aphelion. A numerical calculation of evolution shows that the asteroid could move along this orbit for thousands of years, repeatedly crossing the Earth's orbit. It is likely that this asteroid was formed as a result of collisional processes in the main belt. Being at the perihelion of its orbit approximately two and a half months before the collision, it approached the Earth from the side of the Sun, which prevented its early detection by observatories that constantly monitor the small bodies of the solar system. Table 7 Parameters of the beginning of the destruction and explosion of the meteorite "Chelyabinsk" Parameter Destruction Explosion Height, km 27.7 24.5 Time, IT 03:20:32 03:20:33 Latitude, ° with. sh. 54.78 54.81 Longitude, ° in. d. 61.20 61.04 The black line in Fig. 4 shows the trajectory of the fall, white is the projection of the trajectory, the places of destruction and explosion at points L and B, respectively, the area where the fragments fell, as well as the nearest settlements superimposed on a satellite image of the area. According to calculations, 474 kt of TNT energy was released at the moment of the explosion. In this case, the radius of the destruction zone with an excess pressure at the front of a shock wave of 1 kPa turns out to be equal to 127 km and 51 km for 2 kPa. Such pressure values correspond to the glass strength threshold (see Table 2). The destruction zones are shown in fig. 4 white circles. After the explosion of the meteorite, the motion of 20 groups of fragments with sizes ranging from 1.8 to 0.4 m was simulated. 5 asterisk marks the place where the largest fragment of a meteorite fell, about a meter in size and weighing 654 kg, found in Lake Chebarkul. Numbers 1, 2, and 3 designate the obtained probable areas of fall of the fragments, located in the immediate vicinity of the found fragment, and their parameters are presented in Table. eight. Table 8 Fragment Drop Area Parameters Parameter 1 2 3 Fragment size, m 0.7 0.6 0.6 Fragment weight, kg 646 517 420 Latitude of the center of the region, ° N sh. 54.94 54.93 54.93 Longitude of the center of the region, ° E 60.31 60.33 60.35 Area size, m 1270x354 1216x346 1166x336 Conclusion. The results obtained in the work show that the developed method allows calculating the trajectory of a celestial body in the Earth's atmosphere, the parameters of the body's heliocentric orbit before it enters the atmosphere, to evaluate the region where fragments fall and the main factors of damage. It was shown that the orbits of the 2008 TC3 and Chelyabinsk meteorites before entering the atmosphere turned out to be close to the orbits obtained by other authors, and the parameters of air explosions coincide with the initial data within their accuracy. The resulting areas of fall of fragments of these meteorites are only a few kilometers from the discovered fragments. The zones of destruction as a result of the action of an air shock wave in the case of the Chelyabinsk meteorite coincide with real data, according to which about 7320 buildings were damaged. In some buildings, windows were broken, in others the frames were completely knocked out of the windows. In the Etkulsky district, which became the epicenter of the explosion, 865 windows in residential buildings and 1.1 thousand windows in other buildings were damaged. 1. E. P. Aksenov, Theory of Movement of Artificial Satellites of the Earth. M. : Nauka, 1977. 360 p. 2. Svetsov V. V., Nemtchinov I. V. Disintegration of Large Meteoroids in Earth's Atmosphere: Theoretical Models // Icarus. 1995. Vol. 116. P. 131-153. 3. Passey Q. R., Melosh H. J. Effects of atmospheric breakup on crater field formation // Icarus. 1989. 42. P. 211-233. 4. Ivanov B. A., Deniem D., Neukum G. Implementation of dynamic strength models into 2D hydrocodes: Applications for atmospheric breakup and impact cratering // International Journal of Impact Engineering. 1997. P. 411-430. 5. Chyba C. F., Thomas P. J., Zahnle K. J. The 1908 Tunguska explosion: Atmospheric disruption of a stony asteroid // Nature. 1993. P. 40-44. 6. Physics of explosion / S. G. Andreev [and others]; ed. L. P. Orlenko. In 2 vols. T. 1. 3rd ed., revised. M. : FIZMATLIT, 2002. 832 p. 7. Atamanyuk V. G., Shirshev L. G., Akimov N. I. Civil defense: a textbook for universities / ed. D. I. Mikhailika. M. : Vyssh. school, 1986. 207 p. 8. Google [Electronic resource]. URL: http://www. google.com/earth/ (date of access: 07/15/2014). 9. NASA/JPL [Electronic resource]. URL: http://neo. jpl.nasa.gov/news/2008tc3.html/ (Accessed 7/15/2014). 10. The recovery of asteroid 2008 TC3 / M. H. Shaddad // Meteoritics & Planetary Science. 2010. P. 1-33. 11. Bondarenko Yu. S., Vavilov D. E., Medvedev Yu. D. Method for determining the orbits of small bodies of the solar system based on enumeration of orbital planes. 2014. V. 48, No. 3. S. 229-233. 12. JPL Solar System Dynamics, 2014, SPK-ID: 3430291 [Electronic resource]. URL: http://ssd.jpl.nasa.gov/ (date of access: 07/15/2014). 13. Pit'eva E. V. Fundamental national ephemerides of the planets and the Moon (EPM) of the Institute of Applied Astronomy RAS: dynamic model, parameters, accuracy // Proceedings of the IAA RAS. SPb. : Nauka, 2012. Issue. 23. S. 364-367. 14. U.S. Standard Atmosphere / U.S. Government Printing Office. Washington, D.C., 1976. 15. Groten E. Report of the IAG. Special Commission SC3, Fundamental Constants. XXII. 1999. IAG General Assembly. 16. NOAA [Electronic resource]. URL: http://www.nnvl. noaa. gov/MediaDetail2 .php?MediaID=1290&MediaTypeID=1/ (Accessed 07/15/2014). 17. NASA/JPL [Electronic resource]. URL: http://neo.jpl.nasa. gov/news/fireball_130301. html/ (date of access: 07/15/2014). 18. Zuluaga J. I., Ferrin I., Geens S. The orbit of the Chelyabinsk event impactor as reconstructed from amateur and public footage. 2013.arXiv:1303.1796. 19. Mineralogy, reflectance spectra, and physical properties of the Chelyabinsk LL5 chondrite - Insight into shock induced changes in asteroid regoliths / T. Kohout // Icarus. 2014. V. 228. P. 78-85. 20. Central Bureau for Astronomical Telegrams, IAU. Electronic Telegram No. 3423: Trajectory and Orbit of the Chelyabinsk Superbolide, 2013 [Electronic resource]. URL: http://www.icq.eps.harvard.edu/CBET3423.html/ (accessed 07/15/2014). 21. Astronomical and physical aspects of the Chelyabinsk event of February 15, 2013 / V. V. Emelyanenko [et al.] // Astr. Vestn., 2013. V. 47, No. 4. C. 262277. 22. A. V. Golubev, “Main characteristics of meteoroid motion during the Chelyabinsk meteor shower on February 15, 2013,” Asteroids and Comets. The Chelyabinsk event and the study of the fall of a meteorite into Lake Chebarkul: Proceedings of the Conf. 2013. C. 70. 23. Bondarenko Yu. S. Halley - electronic ephemeris // Proceedings of the Main Astronomical Observatory in Pulkovo. Pulkovo-2012: Tr. Vseros. astrometric conference. 2013. No. 220 S.169-172. 24. URA.RU, The Chelyabinsk meteorite was delivered to the local history museum [Electronic resource]. URL: http://ura.ru/content/chel/17-10-2013/news/1052167381.html (date of access: 07/15/2014). 25. Gazeta.Ru, Non-emergency meteorite [Electronic resource]. URL: http://www.gazeta.ru/social/2013/03/05/50003 89.shtml/ (date of access: 07/15/2014). 1. Aksenov E. P. Teorija dvizhenija iskusstvennykh sputnikov Zemli. . Moscow, Nauka Publ., 1977, 360 p. 2. Svetsov V. V., Nemtchinov I. V., Disintegration of Large Meteoroids in Earth's Atmosphere: Theoretical Models. Icarus, 1995, vol. 116, p. 131-153. 3. Passey Q. R., Melosh H. J. Effects of atmospheric breakup on crater field formation. Icarus 1989, vol. 42, p. 211-233. BecmnuK Cu6FAy. 2014. No. 4(56) 4. Ivanov B. A., Deniem D., Neukum G. Implementation of dynamic strength models into 2D hydrocodes: Applications for atmospheric breakup and impact cratering. International Journal of Impact Engineering, 1997, p. 411-430. 5. Chyba C. F., Thomas P. J., Zahnle K. J. The 1908 Tunguska explosion: Atmospheric disruption of a stony asteroid. Nature, 1993, p. 40-44. 6. Andreev S.G., Babkin A.V. Fizika vzryva. . Vol. 1. Moscow, FIZMATLIT Publ., 2002, 832 p. 7. Atamanjuk V. G., Shirshev L. G., Akimov N. I. Grazhdanskaja oborona: Uchebnik dlja vuzov. . Moscow, Vysshaya shkola Publ., 1986, 207 p. 8. Google. Available at: http://www.google.com/earth/ (accessed: 07/15/2014). 9 NASA/JPL. Available at: http://neo.jpl.nasa.gov/news/2008tc3.html/ (accessed: 07/15/2014). 10. Muawia H. Shaddad, Peter Jenniskens et. al. The recovery of asteroid 2008 TC3. Meteoritics & Planetary Science, 2010, p. 1-33. 11. Bondarenko Yu. S., Vavilov D. E., Medvedev Yu. D. . Astronomicheskij Vestnik. 2014, vol. 48, no 3, p. 229-233. (In Russ.) 12. JPL Solar System Dynamics, 2014, SPK-ID: 3430291. Available at: http://ssd.jpl.nasa.gov/ (accessed: 07/15/2014). 13. Pit "eva EV Fundamental" nye natsional "nye jefemeridy planet i Luny (EPM) Instituta prikladnoj astronomii RAN: dinamicheskaja model", parametry, tochnost" St. Petersburg, Nauka Publ., Proc. of IAA RAS., 2012, vol 23, pp. 364-367 (In Russ.). 14. U.S. Standard Atmosphere, 1976, U.S. Government Printing Office, Washington, D.C., 1976. 15. Groten, E. Report of the IAG. Special Commission SC3, Fundamental Constants, XXII, 1999, IAG General Assembly. 16 NOAA. Available at: http://www.nnvl.noaa.gov/ MediaDetail2.php?MediaID=1290&MediaTypeID=1/ (accessed: 07/15/2014). 17 NASA/JPL. Available at: http://neo.jpl.nasa.gov/news/fireball_130301. html/ (accessed: 07/15/2014). 18. Zuluaga J. I., Ferrin I., Geens S., The orbit of the Chelyabinsk event impactor as reconstructed from amateur and public footage, 2013, arXiv:1303, 1796. 19. Kohout T. et al. Mineralogy, reflectance spectra, and physical properties of the Chelyabinsk LL5 chondrite -Insight into shock induced changes in asteroid regoliths. Icarus, 2014, vol. 228, p. 78-85. 20. Central Bureau for Astronomical Telegrams, IAU. Electronic Telegram No. 3423: Trajectory and Orbit of the Chelyabinsk Superbolide, 2013 Available at: http://www.icq.eps.harvard.edu/CBET3423.html/ (accessed: 07/15/2014). 21. Emel "janenko V. V., Popova O. P., Chugaj N. N. i dr. Astronomicheskij Vestnik. 2013, vol. 47, no 4, p. 262-277 (In Russ.). 22. Golubev A. V. Materialy konferentsii "Asteroidy i komety. Cheljabinskoe sobytie i izuchenie padenija meteorita v ozero Chebarkul" 2013, p. 70 (In Russ.). 23. Bondarenko J. S. Izvestija Glavnoj astronomicheskoj observatorii v Pulkove. Trudy vserossijskoj astrometricheskoj konferencii "Pulkovo-2012". . St. Petersburg, 2013, vol. 220, p. 169-172 (In Russ.). On February 15, 2013, the inhabitants of the Southern Urals witnessed a small asteroid collide with the Earth. In the sky over Chelyabinsk, a celestial body collapsed with an explosion that knocked out windows and damaged several buildings in the city, led to numerous injuries to people from glass fragments ... Numerous surveillance cameras and car DVRs recorded the flight of the car and the consequences of the shock wave - perhaps this is the first in history a case when so many people and so many video cameras watched the fall of a meteorite. Thanks to the results of these video recordings, it is possible to very accurately restore the trajectory of its flight, determine the area where fragments fell, and evaluate the characteristics of the meteorite. Let's try and conduct such a study. Video recordings from car recorders are probably the most impressive, but it is difficult to use them for our purposes, since the wide-angle lenses of the recorders greatly distort the image and, without knowing the parameters of a particular device, one can hardly count on any results. In addition, on many records it is difficult to identify the location of the shooting. So I chose for analysis two recordings of stationary surveillance cameras installed on the streets of Chelyabinsk - on Revolution Square and near the railway station on Razin Street. Revolution Square, 2.4Mb Razin Street, 42Mb True, the meteorite itself is not visible on these records, but the shadow cast by buildings and pillars is perfectly visible. Below are satellite images from the Google Earth program, we will use this program for measurements. Chelyabinsk. Revolution squareChelyabinsk. Razin street Let's try to determine where the meteorite explosion occurred. Since the trajectory of its flight passed almost horizontally, in the first approximation it can be considered that its section closest to the observer is located at the maximum height. Therefore, consider the frame with the shortest shadows. Having restored the position of the column shadow on the satellite image, it is possible to measure its length, the height of the column can be approximately determined from the photographs of the area relative to the height of the cars - it is 12 meters. Now you can determine the maximum height of the meteorite trajectory: φ=arctan(h/L shadow)=arctan(12/16)=37°, where h - column height; Shadow L - the length of the column shadow. Similar calculations can be repeated for the second video, the building in the lower left corner of the frame is the Ostrov shopping center, its height is about 15 meters. The distance to the nearest point of the trajectory can be estimated from the shock wave delay time. It was to the nearest point, since the meteorite was moving at a speed much higher than the speed of sound. The above videos were recorded without sound, but the moment of arrival of the shock wave can be literally seen by the alarms of parked cars. On the video from Razin Street, we will determine the moment of the shortest shadow from the shopping center and the moment the car alarms are triggered: T 1 =0 min 48 s; T 2 =3 min 11 s; ΔT=T 2 -T 1 =143 s; d=ΔT*v sound =143*331=47.3 km, where v sound - speed of sound in air = 331 m/s; d is the slant range to the trajectory. Knowing the maximum angular height of the trajectory and the slant range, we can determine the distance to the nearest point over which the trajectory passed and its height above the ground: D=d*cos(φ)=37.8 km; H=d*sin(φ)=28.5 km. Here it is necessary to make several remarks. This calculation is correct assuming the meteorite's trajectory was horizontal, but it is not. Unfortunately, it is impossible to determine the complete spatial position of the flight path from observation from one point, but we can at least estimate it qualitatively. Since the meteorite was descending and approaching the city (this can be seen from the greater speed of the shadows at the end of the flight), the nearest point of the trajectory must necessarily lie further in the direction of flight than the highest point, that is, to the west, which means that the meteorite did not move exactly from east to west, and from southeast to northwest. Consequently, the height of this point may be somewhat lower than we have determined, and the distance to the projection of the trajectory on the earth's surface is greater. Let's build a circle on the map with a radius D=38.8 km (yellow arrow) - the trajectory should be tangent to it (More precisely, as mentioned above, the radius of the circle should be slightly larger, but not exceed the slant range d=47 km). In addition, we note approximately the directions to the meteorite at the moments of the beginning and end of the flare (at least 45 ° in each direction from the direction to the south) - this angle not only determines the length of the flare segment, but also sets the limiting directions of the trajectory, which must necessarily cross the sides of this angle. Therefore, the direction of flight lies in the sector from 270° to 315° (counting clockwise from the north direction). Below on the map the real path of the meteorite flight is also marked (red arrow) - as we see, it practically coincides with our estimates, taking into account corrections for a decrease in the flight trajectory. It remains to estimate the speed of the meteorite. To improve accuracy, this should be done for the closest part of the trajectory, and therefore, in the sector of the fastest shadow movement in the video. Looking again at the video from the Revolution Square, we see that the entire flash lasted about 5.5-6s, and the time of flight of the meteorite for the second half of the trajectory - from the south until the end of the flash is no more than one and a half seconds. During this time, the meteorite flew at least 20 kilometers, that is, its speed in the final section of the outbreak was at least 12-13 km / s, and it entered the atmosphere at an even higher speed. On the map - the approximate trajectory of the fall of the meteorite Chelyabinsk meteorite- a stone meteoroid that fell on February 15, 2013 near Lake Chebarkul in the Chelyabinsk region. The meteorite fell at 9:20 local time 80 km west of Chelyabinsk. As a result of the fall of the meteorite, 1491 people were injured. According to experts, the mass of the meteorite was up to 10,000 tons, and the diameter was about 15-17 m. The flight of the meteorite body from the moment it entered the atmosphere lasted 32.5 seconds. During the flight in the atmosphere, the meteorite collapsed into many pieces, and therefore fell to the ground in the form of a meteor shower. At a height of 15-25 meters, the meteorite broke up into several parts as a result of a series of explosions. The fall speed of the car was from 20 to 70 km/s. During the fall, the space object left a bright trace, which was visible even in Kazakhstan and the Samara region. When the meteorite was destroyed into several parts, shock waves were formed. According to experts, the total amount of energy released during the destruction of the cosmic body amounted to 500 kilotons in TNT equivalent. Chronicle of the fall of the Chelyabinsk meteoriteAt 9:15 local time, the movement of the cosmic body was seen by residents of the Kostanay and Aktobe regions of Kazakhstan. At 9:21 am, a meteor trail was seen in the Orenburg region. The witnesses of the fall of the meteorite were residents of the Sverdlovsk, Tyumen, Kurgan, Samara and Chelyabinsk regions, as well as the Republic of Bashkortostan. At 9:20 local time, the meteorite fell into Chebarkul Lake, located 1 km from the city of Chebarkul. The fall of parts of the meteorite was observed by fishermen who were fishing near the lake. According to eyewitnesses, about 7 fragments of a cosmic body flew over the lake, one of which fell into the lake, raising a column of water 3-4 meters high. On the satellite map you can see Chebarkul Lake, where the meteorite fell. As a result of the fall of the meteorite, a blast wave was formed, which, in terms of released energy, exceeded the energy of the atomic bombs dropped on Hiroshima and Nagasaki. Due to the gentle trajectory of the entry of the body into the atmosphere, only part of the released energy reached the settlements. The consequences of the fall of the Chelyabinsk meteoriteAs most of the energy dissipated, the blast mostly shattered windows in buildings in nearby communities. A total of 1,491 people were injured in the meteorite impact, but most of the injuries were cuts and bruises from broken windows. Nevertheless, the number of victims of the Chelyabinsk meteorite has no equal in the world. The greatest damage from the disaster was suffered by 6 settlements of the Chelyabinsk region: the cities of Yemanzhelinsk, Chelyabinsk, Korkino, Kopeysk, Yuzhnouralsk and the village of Etkul. The shock wave damaged many buildings: the damage from it was estimated from 400 million to 1 billion rubles. Chelyabinsk zinc plant, the roof of which collapsed from the blast wave of a meteorite Research and study of the Chelyabinsk meteoriteOn February 15, 2013, it was found that fragments of a meteorite fell in the Chebarkul and Zlatoust districts of the Chelyabinsk region. Scientists from URFU have collected meteorite fragments for further study. Later, the researchers told the press that the meteorite was an ordinary chondrite, which is composed of sulfites, iron, olivine and melting crust. Early February morning in 2013 unexpectedly became tragic for 1613 residents of Chelyabinsk and its environs. There has never been such a large number of people affected by a fallen meteorite in the history of the Earth's population. During the impact, windows were broken in many buildings, trees were broken and people were injured to varying degrees of severity, as a result of which about 1,613 people were recognized as victims, of which, according to various sources, from 50 to 100 people ended up in hospitals. People who watched the fall of the meteorite that morning were simply shocked by the events taking place. The first versions of what was happening sounded like: a plane crash, a rocket crash and even an alien attack ... At the moment, the picture of the events of that tragic morning has been fully restored and it is reliably known when and where the meteorite fell in Chelyabinsk. At about 9 am on February 15, this “unexpected guest” appeared high in the sky over Chelyabinsk, as a result of which a state of emergency was declared in Chelyabinsk and its surroundings. Previously, the same meteorite was observed by residents of other regions of the Russian Federation, but they were much more fortunate than the residents of Chelyabinsk, because it simply flew past them without causing absolutely no harm. For example, at 7.15 Moscow time or at 9.15 local time, residents of the Aktobe and Kostanay regions of Kazakhstan saw it, and residents of Orenburg observed this amazing phenomenon at 7.21 Moscow time. This meteorite was also clearly visible in Sverdlovsk, Kurgan, Tyumen and their environs, and even 750 km from the place of impact in the village of Prosvet, Volzhsky district, Samara region. Bright flashAccording to the US National Aeronautics and Space Administration (NASA), a meteorite weighing about 10 tons and a diameter of about 17 meters, with a speed of 17 km / s, entered the Earth's atmosphere and after 32 seconds split into many pieces. The destruction of the meteorite was accompanied by a series of explosions, the first of three explosions was the strongest and caused the destruction. It was a bright flash, it lasted about five seconds, and a minute later it came to Earth in the form of a destructive wave. According to scientists, the destruction of the meteorite led to the release of energy, which was approximately equal to 100 to 500 kilotons of TNT. The center of the explosion was not the city of Chelyabinsk itself, but its area, which is located a little to the south and is called Yemanzhelinsk - Yuzhnouralsk. Locations of the fall of fragmentsAs a result of research conducted by a specially created group, four places were discovered where fragments of the meteorite are supposed to be located. The first two places are in the Chebarkulsky district of the Chelyabinsk region, the third in the Zlatoustovsky district, and the fourth in the Chebarkul lake area. The information that the meteorite is located in the lake was confirmed by the fishermen who were at the crash site. From their stories, members of the search group learned that at the moment the meteorite fell into the lake, a column of water and ice about 3-4 meters high rose from it. Second largest after TunguskaAs a result of the work carried out in the area of Emanzhelinsk and the village of Travniki, about a hundred fragments were found, and about 3 kg of fragments were collected in the lake area. All of them are currently being studied by scientists, according to whom, the meteorite that fell in Chelyabinsk is the second largest after the Tunguska meteorite that fell on the territory of Russia on June 30, 1908.
Based on the foregoing, desperate The May Day boys were in the distance 340×(25+8)= 11220 meters= 11.22 km (340 is the speed of sound in air) from the epicenter of the explosion. The plume break was at an angle of 45-60° from the observer with respect to the horizon (see photo above). Sin50° = 0.766, hence the height at which the explosion occurred, equals 11.22 × 0.766 = 8.58 km, and not 20-30, and even more so not 50 km, as it was stated in the media. This is also evidenced by the shape of the cloud formed by the plume, it is rather cumulus than cirrus. The distance from the observer to a point on the earth's surface under the epicenter will be 11.22 × Cos50° = 11.22 × 0.64 = 7.1 km. We mark this point on the Google Earth map, 7 km from the village of Pervomaisky in the direction opposite to the village of Chebarkul, it will be useful for us to plot the flight path of the “celestial body”. “According to the chairman of the regional branch of the Russian Geographical Society, candidate of geographical sciences Sergey Zakharov, the body flew from the southeast to the northwest, the flight path was in azimuth about 290 degrees along the Yemanzhelinsk-Miass line. In the picture from Kustanai, the car flies from right to left. And in the picture from Kurgan from left to right. Therefore, the flight path passed between these cities.
Of course, we doubted the declared power of the explosion, as well as the likelihood of a meteorite explosion in general. Can a stone meteorite explode, forming such a bright and powerful flash, and burn out, disappearing without a trace? Let's try to answer this question. Moreover, it is quite simple, you still remember the school physics course. Who does not remember, can look into the reference book from which we extracted the following formula: P.S. |
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