Optical and radar meteoroids
The optical and radar researches of the physical properties of the meteoroids of various mass
Tech Area / Field
- SAT-AST/Astronomy/Space, Aircraft and Surface Transportation
- SAT-EXP/Extraterrestrial Exploration/Space, Aircraft and Surface Transportation
- SAT-SAF/Space Safety/Space, Aircraft and Surface Transportation
8 Project completed
Senior Project Manager
Algiyev S K
Institute of Astrophysics, Tajikistan, Dushanbe
- Astronomical Observatory of the A. M. University, Poland, Posnan\nInstitut d'Estudis Catalans, Spain, Barcelona
Project summaryThe need to improve the methods for studies of optical and small radio meteors remains relevant. In the second half of the last century special facilities with radar equipment were set up at Harvard (USA), Adelaide (Australia), Kharkov (Ukraine), Kazan and Obninsk (Russia), Mogadishu (Somalia) and Hissar Astronomical Observatory (Tajikistan). Impulse-diffraction method can typically process about 15-20% meteor detected, which leads to loss of valuable information. Spatio-temporal method used in Hissar Astronomical Observatory exceeds impulse-diffraction method in both sensitivity and precision of measurement. In addition, the materials received at Harvard, Kharkov, Kazan and Obninsk contain information about the meteors smaller than 5th magnitude, and in Mogadishu meteors were observed only at night. The only catalog of meteors brighter than magnitude +5, compiled by radio observations in Australia, contained information only about the meteor radiants located in the southern celestial hemisphere. Therefore radiants, velocities and orbital elements of radio meteors brighter than magnitude +5 located in the northern celestial hemisphere have not been studied.
The observational material obtained by spatio-temporal method at Hissar Astronomical Observatory is free of the above-mentioned shortcomings and provides data on radiants, velocities and orbital elements of radio meteors brighter than magnitude +5 observed in the northern celestial hemisphere. Moreover, the simultaneously conducted TV and radar observations of meteors have produced light curves and ionization curves that make it possible to study the ablation and determine the physical properties of small meteoroids.
Among the many factors that cause a lot of death and destruction in the world, especially dangerous are such phenomena as destructive earthquakes and infiltration of the Earth's atmosphere by meter-sized or decameter-sized meteoroids that survive and can land with devastating consequences. Both events are especially dangerous for the regions with nuclear power plants, chemical plants, hydroelectric dams, and densely populated residential areas because they can lead to regional disasters and human casualties, as evidenced by the Chelyabinsk meteorite on 15 February 2013 in Russia. The energy released by the explosion of large meteoroids in the atmosphere is comparable with the energy of nuclear explosions and can reach the equivalent of tens or hundreds kilotons of TNT.
The project will study the possibility of the presence of large meteorite-dropping meteoroids in the asteroid sources of origin and in the annual meteor steams crossing the Earth's orbit. In addition to the practical value of this issue, it is also important for learning how our solar system developed and what it looked like before the formation of the planets. This information can be obtained in space missions to comets and asteroids or by chemical analysis of meteorite composition. Double or multi-station optical observations of fireballs allow us to determine from where meteorites come to Earth, calculate meteorite orbits and fall positions. Even now meteorites with known orbits are extremely rare (less than 10). The data on meteorite orbit, its velocity, and radiant make it possible to link it with its parent body—an asteroid or comet—and thus have an incredibly cheap way to get information about its source, an asteroid or comet, compared to a costly space mission.
Analysis of meteor interaction with the Earth's atmosphere and ionosphere can also solve some of the problems that are important to people's lives. Evidently, active influence of a meteor on the upper atmosphere causes primary accumulation of M+ ions. Study of the ionospheric E-region is a pressing issue in applied and fundamental research. In applied research, finding reliable precursors of strong earthquakes and their characteristics allows to construct the morphological image of ionosphere at the time preceding an earthquake. Based on empirical evidence, it has been established that several phenomena occur at different altitudes and thus in different regions of ionosphere in the few days or few hours before relatively strong earthquakes. Every year the world experiences more than 100 earthquakes, which causes many casualties and destruction. The search for the means to predict earthquakes has been going on for many years. The problem of long-term prediction has mostly been solved. However, short-term prediction of big earthquakes, at tens of hours before the earthquakes, remains one of the most critical unsolved problems in modern geophysics. Earthquake prediction is a difficult matter. This project can be a valuable step to understanding how to read the signals to predict when and where a strong, over 5 in magnitude earthquake will take place. This project is vital for further development of reliable methods for short-term prediction of strong earthquakes and consequently saving thousands of lives.
The goal of the project is the next:
· The calculation of atmospheric trajectory and orbits on the base of both of photo and radar records of meteors observed in Tajikistan.
· The radar meteor observational data at Hissar astronomical Observatory (HisAO) will be applied to estimate the mass and the bulk density of meteoroid and to study the meteoroid’s ablation. Study the dependence of the ionization coefficient β on the meteoroid atmospheric velocity.
· The theoretical description of the light curve of optical (photo and TV) and radar meteors on the base of quasi-continual fragmentation model. The analysis of the simultaneous observations which do provide a useful check to both radar (limiting magnitude approximately +5) and optical techniques.
· The search of a possible parent body among the Near Earth Asteroids from the current Bowell database and among the meteor showers from the IAU MDC database 2005 for meteorite-dropping bolides. The examination of meteor database to search for possible groups of related objects that include at least one object for which a meteorite survived the atmospheric encounter.
· The research of the influence of metallic ions of the meteoric origin in ionospheric E-region on the formation of the anomalous seismo-ionospheric effects in the period of earthquake preparation to offer the reliable methods of short term earthquake prediction.
Within the framework of the project will be obtained the next results:
On the base of optical and radar observations will be determined the atmospheric trajectory, radiant, velocity and orbit of the meteoroids of various mass observed in Tajikistan. A study of the dependence of the ionization coefficient β on the meteoroid atmospheric velocity will be conducted. The mass and bulk density, strength data and the mechanism of fragmentation of the studied large and small meteoroids will be obtained. This conclusion is very important in the treating meteorite hazard. The results of the search for a possible parent body to be associated with the studied meteorite-dropping bolides will be obtained. The influence of metallic ions of the meteoric origin on the structure of ionospheric E-region will be studied and anomalous seismo-ionospheric effects will be recognized. We could use them as predictors of when and where big earthquakes will occur.
Conformity of the project to purposes ISTC proves to be true involving of scientists of Tajikistan in world scientific community by representation of the results of work under the project at the international conferences and publications papers in foreign scientific journals. Conformity of the project to purposes ISTC consists also in support fundamental and applied researches in the field of the protection of an environment and a life of people against destroying influence of large meteorites with radiated energy of some hundreds TNT equivalent and destructive earthquakes.
The next works will be made within the framework of the project:
· On the base of both of photo and radar records of meteors observed in Tajikistan the calculation of atmospheric trajectory and orbits will be made.
· The radar meteor observational data at Hissar astronomical Observatory (HisAO) will be applied to observed range distributions of meteors to estimate the mass and bulk density of meteoroid, and to study ablation and link small meteoroids to their parent bodies. Will be analyzed the dependence of the ionization coefficient β on the meteoroid atmospheric velocity.
· The light curve of optical (photo and TV) and radar meteors will be described theoretically on the base of quasi-continual fragmentation model. Will be analyzed the simultaneous observations which do provide a useful check to both radar (limiting magnitude approximately +5) and optical techniques.
· The search for a possible parent body will be made among the Near Earth Asteroids from the current Bowell database and among the meteor showers from the IAU MDC database 2005 for meteorite-dropping bolides. The examination of meteor database will be made to search for possible groups of related objects that include at least one object for which a meteorite survived the atmospheric encounter.
· The research of the influence of metallic ions of the meteoric origin in ionospheric E-region on the formation of the anomalous seismo-ionospheric effects in the period of earthquake preparation will be made to offer the reliable methods of short term prediction for a destructive earthquake with magnitude >5.0.
· The catalog of orbital elements and physical-kinematic characteristics about 9 thousand faint radar meteors will be prepared and published.
· Presentation the results obtained within the framework of the project at the international conferences and publications papers in prestigious scientific journals.
The role of Foreign Collaborators: comments to annual and final reports; joint discussion of project results, the publication of common papers in prestigious scientific journals; consultations on methodical questions and the software, direct visits.
Novelty of methodical approach consists in the next:
· The determination of the physical properties of optical and radar meteoroids are based on the modern theory of meteoroids ablation in the Earth’s atmosphere.
· The observational material obtained at Hissar Astronomical Observatory by more sensitive and exact spatio-temporal method.
· The new reliable method for short-term prediction of strong earthquakes is based on the several anomalous seismo-ionospheric effects which occur at E-region of ionosphere.