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The following is the executive summary of Volume 1 of Euroconsult's four volume study, Space Industries and Markets in Russia and Other Countries of the Former Soviet Union. The material reproduced covers space policy and industry in CIS countries, providing a transversal view of CIS space activities and organizations. Generic problems across all fields of applications are analysed; the final focus is on trade with foreign countries. The other volumes cover prospects for satellite communications in the CIS to 2000; prospects for Earth observation satellite systems in Russia and Ukraine to 2000; and prospects for space transportation systems in the CIS to 2000. Information on the whole — some 650 pages — may be obtained from Pauline Byrne at Euroconsult, 71 Boulevard Richard Lenoir, 75011 Paris, France.  相似文献   

3.
Many eminent space lawyers gathered in Singapore to attend the first space law conference to be held in South East Asia. Topics for discussion—which included commercialization of space activities and its effect on the needs of developing countries, and the legal issues of expanding communications and navigation satellite services—were of particular interest to the region. This report summarizes the presentations in each session and presents the conclusions and recommendations—such as the need for a legal instrument to regulate remote sensing—produced.  相似文献   

4.
Multipole Models of the Earth's Magnetic Field   总被引:2,自引:0,他引:2  
Tikhonov  A. A.  Petrov  K. G. 《Cosmic Research》2002,40(3):203-212
To develop a mathematical model of rotational motion of an artificial satellite about its center of mass under the action of various forces (magnetic, Lorentz, etc.) caused by the geomagnetic field, it is necessary to know the induction of the Earth's magnetic field (EMF) as a function of the radius vector of a given point in the near-Earth space. Because the EMF possesses a complex structure and the above-mentioned functional dependence is unavailable in explicit analytic form, a set of approximate models of the EMF should be used. The simplest such model—a right dipole (aligned with the axis of rotation)—does not enable one to reveal in detail the influence of diurnal EMF rotation on the rotational motion of a satellite. The next EMF approximation—an inclined magnetic dipole—does not suffer from the above-mentioned drawback. However, it is shown that not all corrections to the magnetic induction of the EMF of the same order of magnitude are taken into account in the course of transformation from the model of aligned dipole to the model of inclined dipole. So, to develop the EMF model accurately accounting for the absence of axial symmetry of the EMF with respect to the axis of diurnal rotation of the Earth, in general, the effect of the quadrupole component of the geomagnetic potential on the EMF induction (and, probably, even the components of higher orders) must be taken into consideration. By using the International Geomagnetic Reference Field IGRF-2000, the multipole models of the EMF, corresponding to quadrupole, octupole, and higher-order approximations, were constructed and studied in this work. The EMF potential is expressed in terms of its multipole tensors. As a result, projections of the induction and induction gradient of EMF in the center of mass of the satellite onto the axes of the orbital coordinate system can be written in convenient and concise form. The expressions for the first four multipole tensors through the known geomagnetic constants are found. A method for estimating the reliability of these models is put forward, and the regions of applicability of the quadrupole and octupole models are drawn on the plane of orbital parameters.  相似文献   

5.
The issues of freedom of information and protection of national sovereignty have been brought to the fore by the global spread of satellite broadcasting. This article discusses the issues and the international legal strategies that have been adopted to deal with them. It is suggested that the European model—in which states have no right to interfere with reception but broadcasters are obliged to fill 50% of their content with European programs—presents a blueprint that others could follow.  相似文献   

6.
A method for monitoring of sporadic formations in the lower ionosphere by use of the amplitude and phase variations of decimeter radio waves in the occultation trans-ionospheric link GPS satellite — LEO CHAMP satellite is described. Typical variations of the amplitude and phase of the occultation signal, caused by layered formations in the lower ionosphere, are considered. Parameters of sporadic structures measured during period of especially strong solar flashes from October 25 till November 9, 2003, are described. Results of statistical analysis of the occurrence frequency of sporadic layers, their altitude distribution, and thickness are presented. The electron density distribution in the lower ionosphere in the equatorial zone is estimated.  相似文献   

7.
The great improvement in civil observation satellite capabilities over the past two decades—such that the image quality of civil and military satellites is now converging—is demonstrated with the aid of illustrations. The advantages of such progress, eg. new tools for treaty verification, are discussed. Potential problems, including censorship and denial of access to images of one's own country, which may conflict with the UN Remote Sensing Principles, are also highlighted. It is suggested that work on an ASAT treaty should be made a priority for the future.  相似文献   

8.
Structure and thermal control of panel extension satellite (PETSAT)   总被引:1,自引:0,他引:1  
Panel ExTension SATellite (PETSAT) [S. Nakasuka, Y. Nakamura, Panel extension satellite (PETSAT)—a novel satellite concept consisting of modular, functional and plug-in panels, in: 24th International Symposium on Space Technology and Science, invited talk, 2004-o-2, 2004 [1]] is a satellite which is made of several “functional panels”. Each panel has a special dedicated function and various combinations of different kinds of functional panels enable PETSAT to deal with various mission requirement. Development of PETSAT requires four interface requirements. These are mechanical interface, thermal interface, electrical interface and information interface. In this paper, mechanical interface and thermal interface of PETSAT are especially focused on and introduced. In the development of PETSAT issues about mechanical interface corresponds to panel structure and deployment mechanism. The structure of PETSAT is designed so as to have light weigh, enough space for devices and high stiffness. And deployment system has simple mechanism to avoid vacuum metalizing and improve reliability. On the other hand, approaches for thermal interface [K. Higashi, S. Nakasuka, Y. Sugawara, H. Sahara, K. Koyama, C. Kobayashi, T. Okada, Thermal control of panel extension satellite (PETSAT), in: 25th International Symposium on Space Technology and Science, 2006-j-02, 2006 [2]] are homogenization of temperature within panel and between panels. Homogenization of temperature within panels can be realized by heat lane plate, and that between panels is realized by magnetic fluid loop with magnetic heat pump. These approaches for mechanical and thermal interface are demonstrated in SOHLA-2 [Y. Sugawara, S. Nakasuka, T. Eishima, H. Sahara, Y. Nakamura, K. Koyama, C. Kobayashi, T. Okada, Elemental technologies for realization of panel extension satellite (PETSAT), in: 25th International Symposium on Space Technology and Science, 2006-J-01, 2006 [3]] that is satellite of technology demonstration for PETSAT.  相似文献   

9.
Scientists have expended much energy researching SPS but their theories have never yet been realistically tested. It is time for this to change and SPS 2000 — a Japanese-sponsored project to construct and operate a pilot plant to supply electricity to residents of equatorial zones — could provide the means. The project and its benefits are described and the political—economic imperatives for undertaking it presented. The author argues that there are cogent — and practical — reasons for funding a pilot plant, especially given the vast sums spent on other space activities, and on nuclear power, although the latter has never lived up to expectations.  相似文献   

10.
This paper proposes a complete model for assessing the economics of telecommunications satellite systems, accounting for spacecraft development and manufacturing, launch and operations in orbit. This allows to account for such parameters as the mass and lifetime of the satellites, the number and type of payloads, the number of satellites procured and launched, the spare policy, the launch vehicle, the insurances, the satellite average MTTF and the management of the space segment efforts.

The model is divided into four parts: the spacecraft mass model, the spacecraft procurement cost model, the MTTF model and the space segment cost-effectiveness model. It provides for the rapid solution of a number of problems within a wide range of parameters such as assessing the influence on space segment economics of —certain satellite technologies, —satellite and payload mass, —number of payloads per spacecraft, —satellite lifetime, or —spare policy.  相似文献   


11.
The technical development trend of future launch vehicle systems is towards fully reusable systems, in order to reduce space transportation cost. However, different types of launch vehicles are feasible, as there are
• —winged two-stage systems (WTS)
• —ballistic single-stage vehicles (BSS)
• —ballistic two-stage vehicles (BTS)
The performance of those systems is compared according to the present state of the art as well as the development cost, based on the “TRANSCOST-Model”. The development costs are shown versus launch mass (GLOW) and pay-load for the three types of reusable systems mentioned above.It is shown that performance optimization and cost minimization lead to different results. It is more economic to increase the vehicle size for achieving higher performance, instead of increasing technical complexity.Finally it is described that due to the essentially lower launch cost of reusable vehicles it will be feasible to recover the development cost by an amortization charge on the launch cost. This possibility, however, would allow commercial funding of future launch vehicle developments.  相似文献   

12.
This article examines the current legal status of commercial activities in space and describes the legislation — both national and international — existing for their regulation. The question of who is responsible for the action of non-governmental entities is thoroughly discussed, as is the notion of freedom of enterprise. Finally the author looks at the most commercialized areas of space activities — telecommunications and Earth observations — before drawing some conclusions on likely future trends in the privitization and regulation of space activities.  相似文献   

13.
This paper describes outline of the piggy-back satellite “INDEX” for demonstration of advanced satellite technologies as well as for observation of fine structure of aurora. Aurora observation will be carried out by three cameras(MAC) with a monochromatic UV filter. Electron and ion spectrum analyzer (ESA/ISA) will measure the particle phenomena together with the aurora imaging. INDEX satellite will be launched in 2002 by Japanese H2-A. The satellite is mainly controlled by the high-speed, fault-tolerant on-board RICS processor (three-voting system of SH-3). The attitude control is a compact system of three-axis stabilization. Although the size of INDEX is small (50Kg class), several newly-developed technologies are applied to the satellite system, including silicon-on-insulator devices, variable emittance radiator, solar-concentrated paddles, lithium-ion battery, and GPS receiver with all-sky antenna-coverage.  相似文献   

14.
Present operational space telecommunication systems are based on simultaneous availability of more than one satellite on orbit, mainly a spare satellite in addition to the operational one.Considering the costs associated to the delivery of extra flight models and to extra launchers, the question is asked whether it would not be advantageous to launch a very limited number of “overredundant” spacecraft instead of several standard satellites.The paper gives main conditions of reliability, size and redundancy concept under which an “overredundant” spacecraft could be a competitive approach to future operational systems.  相似文献   

15.
The second objective of GARP—climate research—comes more and more into the focus of the scientific community, and the use of satellites and spacelabs to acquire the necessary data is discussed widely. From an inspection of the results of current climate model computations it is attempted in this paper to deduce the criticality of atmospheric parameters with respect to climate and to deduce the required measuring accuracy to get useful data for further climate studies. It emerges that some quantities as the solar flux and albedo have to be determined to better than 1%, and that much improved global information about particles, clouds and gas distribution is necessary. The impact of these requirements on future satellite systems is discussed. One result is the need for comparative and calibrating spacelab missions as well as for adequate ground truth or in situ operations.  相似文献   

16.
Technology advances in sensor, digital technology and a standardised modular satellite bus are enabling a new generation of 80 kg micro-satellites with a better than 6.5 m GSD multi-spectral performance, to be specified, built and deployed with a dedicated launch within 12 months. The result of the standardised modular bus is lower cost, higher reliability and fast deployment. Operational remote sensing with a micro-satellite is thus within reach of individual organisations for dedicated missions. Sumbandilasat (pioneer in the Venda language) is a second generation satellite technology building on the expertise obtained in the Sunsat small satellite programme. The components used to build Sumbandilasat are the result of a technology development program of more than 3 years. Sumbandilasat is an operational technology demonstrator with more than 90% newly developed or improved subsystems and a compact refractive imager as a precursor to the MSMISat satellite with the same multi-spectral band set. The scalable, standardised modular satellite bus architecture enables satellites with a mass of 80–450 kg to be adapted to the specific mission requirements with minimum new engineering effort.  相似文献   

17.
This is a slightly abridged and edited version of the welcoming speech made by European Commission Vice-President Günter Verheugen at the ‘Winning through co-operation: sharing the benefits of space’ conference held in Brussels on 17–18 February 2005 as part of European Space Week. The importance of space for Europe across many areas—now explicitly acknowledged by the European Commission—is highlighted. Future initiatives are discussed and the Union's approach to international cooperation is outlined. It was hoped that the conference would provide an opportunity for participants to identify the best opportunities for partnership in space.  相似文献   

18.
The results of measurements of fluxes and spectra carried out using the RELEC (relativistic electrons) equipment onboard the VERNOV satellite in the second half of 2014 are presented. The VERNOV satellite was launched on July 8, 2014 in a sun-synchronous orbit with an altitude from 640 to 830 km and an inclination of 98.4°. Scientific information from the satellite was first received on July 20, 2014. The comparative analysis of electron fluxes using data from RELEC and using experimental data on the electron detection by satellites Elektro-L (positioned at a geostationary orbit) and Meteor-M no. 2 (positioned at a circular polar orbit at an altitude of about 800 km as the VERNOV satellite) will make it possible to study the spatial distribution pattern of energetic electrons in near-Earth space in more detail.  相似文献   

19.
One of the forms of astroengineering activity that a very advanced civilization could possibly carry on is the constructions of huge “buildings” in space around the central star. Historically such constructions are called Dyson Spheres. We would like to introduce a new name — Astroengineering Constructions (AC) — to mean a more general type of construction not necessarily related to any specific star. AC absorb energy from different types of activity and re-emit it as infrared radiation, i.e. radiation lying in the submillimeter and millimeter range. Further, AC are expect to have spectra similar to the black-body spectra because they re-emit all the energy that they absorb, although in the infrared range, as already mentioned. Thus, the effective temperature of these Planckian distributions is expected to lie between 3–300 K with the spectrum peaking between 10 μm and 10 mm. We have analyzed the IRAS database and extracted a catalog of sources whose spectra are similar to the black-body emission. The catalog of these sources and their preliminary parameters are discussed. The distribution of the color temperatures of IRAS sources and the sky distribution of sources are also considered. The possibility of the distinction of AC from thick circumstellar dust shells around red giant stars is discussed.  相似文献   

20.
Science return and high bandwidth communications are one of the key issues to support the foreseen endeavours on next generation missions [J.L. Gerner, Telemetry, tracking and command of satellites—a perspective, TT&C 2004 Workshop, 7–9 September 2004]. Interplanetary telecommunication systems are required that support the foreseen endeavours. Given the same constraints in terms of mass, power and volume a laser communications terminal can offer an increase in telemetry bandwidth over classical RF technology allowing for a variety of new options, specifically to missions that require large distances, such as to the Moon, to liberation points L1 and L2, ultimately aiming at deep space missions. An increase in telemetry data rate allows the mission to consider the processing of raw scientific data to take place on ground, making use of latest technology further developed during the cruise phase of the probe, rather than applying data pre-processing on-board the satellite. Enhanced sensing techniques that generate more science data return could be used and access to data during flight could be faster. Results of on-going activities will be presented, comprising PPM laser communications and advanced tracking concepts. An overview will be given of the system concept for an integrated RF-optical TT&C transponder. Results will be shown from hardware tests on communications performance in inter-island test campaigns.  相似文献   

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