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1.
流星光学监测网是定位陨石和观测火流星的基础科研设施. 流星光学监测系统利用光学相机高速采集天空图像, 使用嵌入式系统实时处理数据, 能够快速识别流星并获取流星位置和陨石落点信息, 是构成流星监测网的关键仪器. 为提高流星光学监测系统获取信息的实时性及准确性, 提出了一种基于嵌入式人工智能设备的流星光学监测系统. 该系统由软件及硬件部分组成: 硬件部分包括观测设备(商用高空抛物摄像头)以及数据处理设备(嵌入式人工智能设备); 软件部分运行于数据处理设备内, 主要包括控制界面模块、流星监测模块、数据管理模块. 实际工作时, 摄像头采集天空视频信息, 流星监测模块从视频流中实时监测流星并存储包含流星视频的数据, 数据管理模块将流星位置信息实时传回数据中心用于预警. 观测结束后, 将原始观测数据同步至数据中心用于后续科学研究. 在整个系统中, 流星监测模块决定了整个监测系统的实时性及准确性. 该系统采用嵌入式人工智能设备与人工智能算法结合的方法构建流星监测模块. 通过使用实测数据对搭载监测模块性能进行测试, 结果表明: 流星监测模块能够达到0.28%的低误检率以及100%的召回率, 且数据处理速度达到了Mobilenetv2的8倍. 进一步将包含监测模块的整个流星光学监测系统部署于太原理工大学-张壁古堡远程天文台, 通过实测表明流星光学监测系统实用中能达到100%的召回率和较低的误检率.  相似文献   

2.
The meteor radar response function is an important tool for analyzing meteor backscatter observed by radar systems. We extend previous work on the development of the response function to include a non-uniform meteor ionization profile, provided by meteor ablation theory, in contrast to what has been assumed in the past. This has the advantage that the height distribution of meteors expected to be observed by a radar meteor system may be accurately modeled. Such modeling leads to meteor height distributions that have implications for the composition of those meteoroids ablating at high altitudes which may be observed by “non-traditional” meteor radars operating at MF/HF. The response function is then employed to investigate meteor backscatter observed by narrow beam MST radars which in recent years have been used increasingly to observe meteors.  相似文献   

3.
An ever increasing variety of electronic instrumentation is being brought to bear in meteor studies and analysis, with unique meteor detection challenges arising from the attempt to do automated and near real-time processing of the imagery. Recent algorithm developments in the literature have been applied and implemented in software to provide reliable meteor detection in all-sky imagers, wide-field intensified video, and narrow field-of-view telescopic systems. The algorithms that have been employed for meteor streak detection include Hough transforms with phase coded disk, localized Hough transforms with matched filtering, and fast moving cluster detection. They have found application in identifying meteor tracks in the Spanish Fireball Network all-sky images, detailed analysis of video recordings during the recent Leonid meteor storms, and development of a detection/cueing technology system for rapid slew and tracking of meteors.  相似文献   

4.
Under the title ‘Meteors, Meteoroids and Interplanetary Dust’, meteor research is included in the program of the International Heliophysical Year 2007/9.We list issues for coordinated meteor research within the framework of this global international program.  相似文献   

5.
This paper describes the progress on the Virtual Meteor Observatory (VMO), a database which is being developed at ESA/RSSD to store video meteor observations and their derived orbits. The VMO was triggered by a discussion which took place at the first Meteor Orbit Determination (MOD) workshop in Roden, The Netherlands, in September 2006. Representatives of 15 groups working on the determination of meteor orbits and working with the resulting orbits discussed the design and implementation of a database which would combine different meteor orbit datasets. From this the concept of the VMO was born, which will, in the long run, allow accessing meteor observations via the internet. In the beginning, it will focus on meteor orbit data obtained with video systems. This paper presents the architectural design of the database as it has been defined in the meantime.  相似文献   

6.
7.
The 33.2 MHz interferometric meteor radars located at Davis Station, Antarctica and Darwin, Australia typically detect around 15 000 specular underdense meteor echoes every day. While the angle of arrival of the scattered radio wave can be inferred using phase differences between receive antennae, the direction of individual meteors is not known beyond a plane of ambiguity perpendicular to the angle of arrival. Using the great circle mapping technique with a Jones & Jones type weighting function, 37 meteor shower systems were detected in data collected at both locations over 2006–2007, including nine undocumented showers. The orbital elements of the parent debris streams were then calculated for the 31 showers where sufficiently precise measurements were available.  相似文献   

8.
Both amateur and professional meteor groups are more frequently using Low-Light level TV (LLTV) systems to record meteors. Double-station observations can yield orbit data. However, data analysis normally is still done by hand and thus time consuming. This paper addresses the question of whether available automated tools can be used to determine reasonably accurate orbits with minimum human intervention. The European Space Agency performed several observing campaigns to observe the Leonid meteor stream. In November 1999, the ESA meteor group was stationed at two locations in Southern Spain, in November 2001 at two stations close to Broome in North-Western Australia. Double-station observations with LLTV systems were conducted. The data was recorded on S-VHS video tapes. The tapes were processed using automatic detection software from which meteor heights, velocities and radiants were computed. This paper shows the results for the two maximum nights. The radiants determined in 1999 show a very large scatter due to unfortunate observing geometry and inaccurate position determination since one of the cameras was moving because of the wind. The 2001 data is excellent and the radiant was determined to be at RA = 153.96°±0.3° and Dec = 21.09°±0.2°. The error bars for individual meteor radiants are about 0.2° to 0.4°. This demonstrates that is indeed possible to determine good radiant positions using totally automated tools. Orbits, on the other hand, are not well defined due to the fact that the velocity of individual meteors shows large errors. Reasons for this are described.  相似文献   

9.
The asteroid 3200 Phaethon is suggested as a candidate for direct impact research. The object is considered to be an extinct comet and the parent of the Geminid meteor shower. One could say that this provides a possible argument for a space mission. Based on such a mission, this paper proposes to investigate the nature of the extinct comet and the additional interesting possibility of artificially generated meteor showers.
Dust trail theory can calculate the distribution of a bundle of trails and be used to show in which years artificial meteors would be expected. Results indicate that meteor showers will be seen on Earth about 200 yr after the event, on 2022 April 12.  相似文献   

10.
吴光节 《天文学进展》2001,19(4):457-469
对近20年来狮子座流星雨的预报工作,进行了系统的阐述和分析。1998年Tempel-Tuttle彗星的回归,再度带来了狮子座流星雨的观测热,也大大促进了对狮子座流星雨预报工作的研究与验证。有的研究在时间预报准确度方面已显示出其模型的优越性,有的在流星雨的强度方面显示出一定的准确度。指出了两大类不同的方法实际上是在三维空间强调了不同的方面。将不同方法的优势结合起来,可能会使流星雨的预报更加成熟。  相似文献   

11.
Abstract— In this paper, we study the extremely high beginning parts of atmospheric trajectories of seven Leonid meteors recorded by sensitive TV systems equipped with image intensifiers up to apparent magnitude +6.5. For all seven cases, we observed comet‐like diffuse structures with sizes on the order of kilometers that developed quickly during the meteoroids' descent through the atmosphere. For the brightest event with a maximum absolute magnitude of ?12.5, we observed an arc similar to a solar protuberance and producing a jet detectable several kilometers sideways from the brightest parts of the meteor head, and moving with a velocity over 100 km/s. These jets are common features for the seven studied meteors. Precise position in trajectory, velocity, and brightness at each point is available for all seven meteors, because of double‐station records on 85 km base‐line. When these meteoroids reached 130 km height, their diffuse structures of the radiation quickly transformed to the usual meteor appearance resembling moving droplets, and meteor trains started to develop. These meteor phenomena above 130 km were not recognized before our observations, and they cannot be explained by standard ablation theory.  相似文献   

12.
We discuss a new method for measuring the coordinates of meteor shower radiants from meteor radar data. The method uses a high accuracy of radar goniometer measurements of one of the angular coordinates for meteor radiants and collective properties of incident meteor showers. It is based on a computer technology of searching for the coordinates of radiants using the intersections of meteor position lines on the celestial sphere and filtering nonrandom combinations of these intersections. The method allows the following: to detect meteor showers with a rate of more than 5 per day of observations and to separate meteor groups from different meteor showers with different radiants and velocities. The method makes it possible to increase the angular resolution from 10° × 10° achieved with a quasi-tomographic technique to 2° × 2°, with a prospect of a further increase in the accuracy through the individual reduction of separated meteor groups. We use the reduction of one-day-long observations during maximum activity of the Geminids meteor shower in 1993 to illustrate the potentialities of the method. We show an example of detecting a weak meteor shower that was active during December 1993.  相似文献   

13.
A review of TV and telescopic methods of meteor observations and of the problems of meteor astronomy addressed using these methods is presented. A meteor patrol developed at the Astronomical Observatory of Odessa National University and based on a Schmidt telescope and a TV detector is described. The meteor patrol allows meteor events to be recorded with a time resolution of 0.04 s. The investigated characteristics of the patrol are reported, and some aspects of the methods of observations and reduction employed are considered. The results of observations made during the period 2003–2004 are reported. A total of 368 meteors were recorded on 1093 individual frames during a total patrol time of 679 hours within a 36′ × 48′ field of view. The statistical data for meteor observations are reported, and classification of meteor images is presented. The specific features of some recorded meteor events are analyzed.  相似文献   

14.
During the Leonid meteor shower of November 1999 a very bright meteor train, subsequently called the Y2K meteor, was observed. Analysis of the trajectory of the meteor suggests that it was composed of two distinct materials. The bulk of the meteor was composed of a comet-like material, while a much smaller fraction was of a denser carbonaceous material. A simple model is used to analytically determine the mass of the meteor fragments. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

15.
Radio meteor observations by Ham-band beacon or FM radio broadcasts using “Ham-band Radio meteor Observation Fast Fourier Transform” (HROFFT) an automatic operating software have been performed widely in recent days. Previously, counting of meteor echoes on the spectrograms of radio meteor observation was performed manually by observers. In the present paper, we introduce an automatic meteor echo counting software application. Although output images of the HROFFT contain both the features of meteor echoes and those of various types of noises, a newly developed image processing technique has been applied, resulting in software that enables a useful auto-counting tool. There exists a slight error in the processing on spectrograms when the observation site is affected by many disturbing noises. Nevertheless, comparison between software and manual counting revealed an agreement of almost 90%. Therefore, we can easily obtain a dataset of detection time, duration time, signal strength, and Doppler shift of each meteor echo from the HROFFT spectrograms. Using this software, statistical analyses of meteor activities is based on the results obtained at many Ham-band Radio meteor Observation (HRO) sites throughout the world, resulting in a very useful “standard” for monitoring meteor stream activities in real time.  相似文献   

16.
We propose a technique for reducing the number of meteors observed at a single ground-based station to estimate the influx rate of meteoric material to the Earth (MAI—meteor activity index). We derive a formula that allows the meteor activity to be objectively estimated from the results of meteor detection by assuming that each meteor belongs to a stream with a uniform spatial particle distribution. As an example, we give meteor activity estimates obtained from the results of meteor detection by a patrol TV camera located at a single station.  相似文献   

17.
《New Astronomy》2007,12(1):52-59
In the present age, several techniques for the application to the observation of meteors and meteor showers have been developed in modern meteor astronomy. The initial definition for a meteor storm based on the visual observation with a Zenithal Hourly Rate of above 1000 seems insufficient now, since it only means a storm or burst of meteors in numbers and means that an eyewitness could have a chance to see a spectacular meteor show. Up to now, peoples have also recorded the meteoric flashes on the Moon during the Leonid meteor showers. Especially, the increasing activities of mankind in space for scientific, commercial and military purposes, have led to an increase in the problems concerning the safety of the satellites, space stations and astronauts. How the intense activity of a meteor storm is defined and forecast, some new points of view are needed. In this paper, several aspects about the intensity of the meteor storm are analyzed, including the number, mass, impulse, energy, electric charge, different purposes and different physical meanings. Finally, a synthetical index denoting the activity and potential threat of an intense meteor shower is suggested.  相似文献   

18.
We present a low cost meteor observation system based on the radio forward scattering and interferometry technique at Kochi University of Technology (KUT). The system can be a suitable model for low budget educational institutes that target practical learning of astronomical objects and upper atmospheric characteristics. The system methodology for the automatic counting of meteor echoes, filtering noise and detecting meteor echo directions is described. Detection of the meteor echo directions, which is the basic element for determining the meteor trajectories and the orbital parameters of parent comets, is based on a software system developed for analysis of phase differences detected by interferometry. Randomly selected observation samples measured by the radio interferometer are compared to simultaneous optical observations by video cameras to verify the system accuracy. Preliminary error analysis revealed that the system accuracy is directly related to the duration of observed meteor echoes. Eighty percent of meteor echo samples with durations longer than 3 s showed agreement in azimuth and elevation angles measurements to within a 10° error range, while meteor echo samples with shorter durations showed lower agreement levels probably due to the low system sampling resolution of 0.1 s. The reasonable agreement level of meteor echoes with duration longer than 3 s demonstrated the applicability of the system methodology. Accurate observation of shorter duration meteor echoes could possibly be achieved by improving the system resolution.  相似文献   

19.
Probably the majority of meteor showers has a cometary origin. Investigation of Near-Earth asteroids' orbital evolution to determine whether they have related meteor showers are necessary to determine which asteroids evolved from comets. The results of calculations show that asteroid Orthos' orbit is an octuple Earth-crosser. Therefore, if Orthos has an old meteoroid stream it may produce eight meteor showers observable on the Earth. The existence of four Orthos' Northern meteor showers is confirmed by our search in the published catalogues of meteor radiants and orbits or in the archives of the IAU Meteor Data Center (Lund, Sweden).  相似文献   

20.
Probably most meteor showers have a cometary origin. Investigation of Near-Earth asteroids' orbital evolution to determine whether they have related meteor showers is necessary to determine which asteroids evolved from comets. The results of calculations show that asteroid Orthos' orbit is an octuple Earth-crosser. Therefore, if Orthos has an old meteoroid stream it may produce eight meteor showers observable on the Earth. The existence of four Orthos' Northern meteor showers is confirmed by our search in the published catalogues of meteor radiants and orbits or in the archives of the IAU Meteor Data Center (Lund, Sweden).  相似文献   

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