共查询到20条相似文献，搜索用时 31 毫秒
1.
N. S. Bakhtigaraev P. A. Levkina L. V. Rykhlova V. V. Chazov A. V. Sergeev N. V. Karpov 《Kinematics and Physics of Celestial Bodies》2016,32(5):233-236
The Zeiss-2000 telescope of the International Center for Astronomic and Medico-Ecological Research, National Academy of Sciences of Ukraine (Terskol observatory), with a 2-meter aperture is the largest optical instrument in Europe that is regularly used for investigating space debris in the vicinity of the geostationary orbit. One of the main objectives is to detect and characterize small fragments of space debris that are difficult to approach for other telescopes. During each photometric night, we usually detect four to five unknown fragments of 17th to 20th magnitude. This article provides orbital parameters and physical characteristics of several small-sized fragments of space debris that were detected during observations at Terskol observatory in 2014–2015. 相似文献
2.
The observations on ground-based facilities miss multitudes of small fragments of space debris. However, the intrusion of
fine particles into the atmosphere and their subsequent burning can be observed along with the usual meteor phenomena. Since
the solar system meteoric body velocities at the entry into the atmosphere are over 11.2 km/s, and the velocity of the space
debris objects does not exceed 11.2 km/s, the selection of meteors by velocity is a reliable criterion for separating these
bodies. The paper describes a method of selecting the space debris fragments using a technique of television meteor monitoring.
The technique was adapted on the material of real television observations on the FAVOR wide-field monitoring camera with high
temporal resolution, conducted in 2006 in the Arkhyz station of the Institute for Precision Instrumentation (North Caucasus). 相似文献
3.
This paper describes the numerical models designed by the authors to investigate the formation, orbital evolution, and spatial
distribution of fragments of space debris emerging in orbits as a result of space-craft fragmentation. It cites the results
of the testing of the models and the data of their use. 相似文献
4.
I. V. Barmin D. W. Dunham V. P. Kulagin V. P. Savinykh V. Ya. Tsvetkov 《Solar System Research》2014,48(7):593-600
The formation of space debris as an accumulation of small heavenly bodies in near-Earth space is considered. How debris can arise in near-Earth space is described. The accumulation of debris is shown to have a ring structure. The formation and spatial distribution of debris are statistically analyzed. A hypothesis for the formation of debris rings in near-Earth space is proposed. 相似文献
5.
Thomas Schildknecht 《Astronomy and Astrophysics Review》2007,14(1):41-111
Space debris—man-made non-functional objects of all sizes in near-Earth space—has been recognized as an increasing threat
for current and future space operations. The debris population in near-Earth space has therefore been extensively studied
during the last decade. Information on objects at altitudes higher than about 2,000 km is, however, still comparatively sparse.
Debris in this region is best detected by surveys utilizing optical telescopes. Moreover, the instruments and the applied
observation techniques, as well as the processing methods, have many similarities with those used in optical surveys for ‘astronomical’
objects like near-Earth objects (NEOs).
The present article gives a general introduction to the problem of space debris, presents the used observation and processing
techniques emphasizing the similarities and differences compared to optical surveys for NEOs, and reviews the results from
optical surveys for space debris in high-altitude Earth orbits. Predictions on the influence of space debris on the future
of space research and space astronomy in particular are reported as well. 相似文献
6.
The scatter of the fragments of a dissociated meteoroid, which is caused by their deviation from the original flight-path due to distinctive features of their aerodynamic shape, is investigated. For fragments of the simplest geometric shape, it is shown by numerical simulations that this mechanism contributes to expanding the debris cloud no less than the interaction between the fragments immediately following breakup, while they are surrounded by a common shock wave. An approximate formula is proposed for assessing the debris scatter of the disrupted body, and this formula may be used to evaluate the parameters of crater fields. 相似文献
7.
Walter Flury 《Earth, Moon, and Planets》1995,70(1-3):79-91
37 years of space activities have led to a large number of anthropogenic objects orbiting the Earth. Ground-based observations with radar and optical facilities reveal the existence of about 7500 objects in space, which do not represent an immediate excessive danger. However, adequate actions are required to keep the long-term debris hazard for manned and unmanned missions within acceptable tolerances. In this paper the space debris environment of the Earth and its future evolution are described. New developments which could have a major impact on the space environment, are the the planned multi-satellite constellations for communications purposes or solar power stations in Earth orbit. Finally, methods for debris reduction are outlined. Space debris is a global problem which can only be effectively solved by international cooperation. 相似文献
8.
《New Astronomy》2020
In March 2019 the first dedicated of optical observation of space debris and artificial satellites (Optical Satellites Tracking Station (OSTS)) in Egypt has been performed by National Research Institute of Astronomy and Geophysics (NRIAG) at Kottamia Observatory. The 0.28 m Telescope is used for tracking and surveying debris and operational satellites at Low Earth Orbit (LEO), High ellipse orbit (HEO) and the Geosynchronous Earth Orbit (GEO). OSTS has also collaborated with International Scientific Optical Network (ISON) for optical observation. The necessary programs to control the telescope, camera and monitoring process are configured. Coordinate corrected metric data is provided with the time information. The system has validated and calibrated processing. The first results of the observations with image processing using Apex-2 software are presented. The optical observations using OSTS are being used to help characterize the debris environment in LEO, HEO and GEO to assist in the modeling projections for space debris database, real population and distribution, detection and orbital determination, and conjunction analysis between operational satellites and/or dangers debris. 相似文献
9.
空间碎片天基光电光学可见条件与预报 总被引：1，自引：0，他引：1
随着航天活动的增加，产生的空间碎片也越来越多，空间环境日趋恶化，已经对人类的空间活动构成了威胁。监视测量这些空间碎片，天基光电比地基光电更为有利，而天基光电的光学可见条件与地基光电相比，有相似的，也有不同的，针对天基光电，给出了空间碎片的光学可见条件，即日光条件、地影条件、地光条件、地球背景条件、月光条件。在天基光电轨道特征、光学可见条件及天基光电坐标系已知的情况下，建立起天基光电预报方法。既可用于空间碎片预报，也可以用于空间碎片的轨道识别。 相似文献
10.
The processes of space debris formation are described; the urgency of the problem of its removal from near-Earth space is noted. A method to prevent the clogging of space by equipping a spacecraft to be launched into orbit with additional devices, simple in design and mode of operation, is presented. The results of the estimation of aerothermodynamics, bulk–mass characteristics and trajectories of low-orbit spacecraft equipped with a space debris disposal system are presented. 相似文献
11.
12.
Yang Kejun 《时间频率学报》1995,(1)
本文分析了利用中国科学院陕西天文台的流星雷达进行人为空间碎片监测的可能性．详细计算了到达接收机的回波的信噪比Ｓ／Ｎ依赖于目标散射横截面。和高度距离Ｒ的关系。理论计算表明，利用陕西天文台的流星雷达完全有可能监测在２００ｋｍ至１２００ｋｍ的高度范围内，半径大于０．５ｍ的人为空间碎片． 相似文献
13.
《天文和天体物理学研究(英文版)》2014,(8)
In order to implement an observing strategy,image degradation that occurs during optical observation of space debris is ineluctable and has distinct characteristics. Image restoration is presented as a way to remove the influence of degradation in CCD images of space debris,based on assumed PSF models with the same FWHM as images of the object. In the process of image restoration,the maximum entropy method is adopted. The results of reduction using observed raw CCD images indicate that the precision in estimating positions of objects is improved and the effects of degradation are reduced. Improving the astrometry of space debris using image restoration is effective and feasible. 相似文献
14.
Comprehensive analysis of space debris rotational dynamics is vital for active debris removal missions that require physical capture or detumbling of a target. We study the attitude motion of large space debris objects that admittedly pose an immediate danger to space operations in low Earth orbits. Particularly, we focus on Sun-synchronous orbits (SSO) with altitude range 600–800 km, where the density of space debris is maximal. Our mathematical model takes into account the gravity-gradient torque and the torque due to eddy currents induced by the interaction of conductive materials with the geomagnetic field. Using perturbation techniques and numerical methods, we examine the deceleration of the initial fast rotation and the subsequent transition to a relative equilibrium with respect to the local vertical. A better understanding of the latter phase is achieved owing to a more accurate model of the eddy-current torque than in most prior research. We show that SSO precession is also a crucial factor influencing the motion properties. One of its effects is manifested at the deceleration stage as oscillations of the angular momentum vector about the direction to the south celestial pole. 相似文献
15.
The space debris detectin will become greater and greater in the near future with the space debris enhancing. We introduce a theoretical approach of this problem assuming the using of a new generation large coronograph. We get some interesting — and alarming — results about the great probability to be able to observe space debris with this new ground-based large coronograph. 相似文献
16.
17.
Study of a Bistatic Radar System Using VLBI Technologies for Detecting Space Debris and the Experimental Verification of its Validity 总被引：1，自引：0，他引：1
Masanobu Yajima Kazutomo Tsuchikawa Toshiyuki Murakami Kazuyoshi Katsumoto Tadashi Takano 《Earth, Moon, and Planets》2007,100(1-2):57-76
Space debris are increasing around the Earth. The observation of space debris is a key issue for the investigation and monitoring
of space environment. But the observation opportunities and the detection ability are limited in existing monostatic radar
systems. This paper proposes a bistatic radar which is composed of a transmitting station and a receiving-only station. A
carrier wave modulated by PN-PSK signals is used in combination with a VLBI (Very Long Baseline Interferometry) recorder for
range measurement between space debris and stations. The receiving radio wave is processed on the basis of VLBI techniques.
Accordingly, the system is shown to have significant advantages over a monostatic radar. We actually formed a bistatic radar
system, and observed a satellite in order to experimentally verify the validity. The configuration of the system, data analysis
and the experimental results are described. 相似文献
18.
《天文和天体物理学研究(英文版)》2017,(3)
The increasing number of space debris has created an orbital debris environment that poses increasing impact risks to existing space systems and human space flights. For the safety of in-orbit spacecrafts, we should optimally schedule surveillance tasks for the existing facilities to allocate resources in a manner that most significantly improves the ability to predict and detect events involving affected spacecrafts. This paper analyzes two criteria that mainly affect the performance of a scheduling scheme and introduces an artificial intelligence algorithm into the scheduling of tasks of the space debris surveillance network. A new scheduling algorithm based on the particle swarm optimization algorithm is proposed, which can be implemented in two different ways: individual optimization and joint optimization. Numerical experiments with multiple facilities and objects are conducted based on the proposed algorithm, and simulation results have demonstrated the effectiveness of the proposed algorithm. 相似文献
19.
Daniel D Durda William F Bottke Jr. William J Merline Derek C Richardson 《Icarus》2004,167(2):382-396
We present results of 161 numerical simulations of impacts into 100-km diameter asteroids, examining debris trajectories to search for the formation of bound satellite systems. Our simulations utilize a 3-dimensional smooth-particle hydrodynamics (SPH) code to model the impact between the colliding asteroids. The outcomes of the SPH models are handed off as the initial conditions for N-body simulations, which follow the trajectories of the ejecta fragments to search for the formation of satellite systems. Our results show that catastrophic and large-scale cratering collisions create numerous fragments whose trajectories can be changed by particle-particle interactions and by the reaccretion of material onto the remaining target body. Some impact debris can enter into orbit around the remaining target body, which is a gravitationally reaccreted rubble pile, to form a SMAshed Target Satellite (SMATS). Numerous smaller fragments escaping the largest remnant may have similar trajectories such that many become bound to one another, forming Escaping Ejecta Binaries (EEBs). Our simulations so far seem to be able to produce satellite systems qualitatively similar to observed systems in the main asteroid belt. We find that impacts of 34-km diameter projectiles striking at 3 km s−1 at impact angles of ∼30° appear to be particularly efficient at producing relatively large satellites around the largest remnant as well as large numbers of modest-size binaries among their escaping ejecta. 相似文献
20.
Daniel D. Durda William F. Bottke Jr. William J. Merline Derek C. Richardson 《Icarus》2004,170(1):243-257
We present results of 161 numerical simulations of impacts into 100-km diameter asteroids, examining debris trajectories to search for the formation of bound satellite systems. Our simulations utilize a 3-dimensional smooth-particle hydrodynamics (SPH) code to model the impact between the colliding asteroids. The outcomes of the SPH models are handed off as the initial conditions for N-body simulations, which follow the trajectories of the ejecta fragments to search for the formation of satellite systems. Our results show that catastrophic and large-scale cratering collisions create numerous fragments whose trajectories can be changed by particle-particle interactions and by the reaccretion of material onto the remaining target body. Some impact debris can enter into orbit around the remaining target body, which is a gravitationally reaccreted rubble pile, to form a SMAshed Target Satellite (SMATS). Numerous smaller fragments escaping the largest remnant may have similar trajectories such that many become bound to one another, forming Escaping Ejecta Binaries (EEBs). Our simulations so far seem to be able to produce satellite systems qualitatively similar to observed systems in the main asteroid belt. We find that impacts of 34-km diameter projectiles striking at 3 km s−1 at impact angles of ∼30° appear to be particularly efficient at producing relatively large satellites around the largest remnant as well as large numbers of modest-size binaries among their escaping ejecta. 相似文献