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1.
Henry R. Hertzfeld   《Space Policy》2007,23(4):210-220
Economic and commercial spacepower is about market dominance and control. The USA is still the largest investor in space in the world and the technological and commercial leader in many areas but its leadership is being challenged. When other nations have similar capabilities, control becomes a problem, assuming, as is the case with space, that control is also a critical issue in security. Moreover, exerting spacepower may be inconsistent with expanded commercial developments in space, raising investment risks and creating incentives for foreign competitors. To the extent that global market opportunity is denied by restrictive commercial policies, spacepower from a purely international economic competitive perspective is diminished. Though it is encouraging that the US commercial space policies have been in Presidential Documents over the past 20 years, they have been unintentionally undermined to a large extent by other policies, with security almost always trumping commerce. This paper examines the way globalization and commercial space developments have changed the nature of spacepower and suggests that the USA's reactions to these changes have not thus far served it well.  相似文献   

2.
随着全球低轨星座系统的快速部署及应用,非静止轨道卫星对静止轨道卫星系统的同频干扰问题日益凸显。为保护静止轨道卫星系统不受有害干扰,国际电联现行无线电规则中规定了非静止轨道卫星系统应满足的等效功率通量密度限值或干扰噪声比限值,但所适用频段及限值标准仍在不断修订完善中。为了精确定量评估低轨星座对静止轨道卫星的同频干扰,通过对等效功率通量密度限值和干扰噪声比限值的确定方法及演进历程进行研究,分析了上述限值与静止轨道卫星实际被干扰的对应关系,并以典型倾斜轨道星座和极地轨道星座为例,分析了不同干扰指标对卫星系统间干扰判定结果的影响,当静止轨道卫星系统的实际被干扰门限低于国际电联制定等效功率通量密度限值选用的参考门限时,建议低轨星座选择干扰噪声比限值作为开展频率干扰分析与判定的依据。  相似文献   

3.
For several years there has been substantial growth in the ‘nationalist’ nature of space programmes around the world, traditionally focused on unaligned useful space applications. It seems that China, India, in the future South Korea, Malaysia and others will set themselves objectives of a more political colouring symbolising national pride in their programmes. At the same time, some countries, like Iran, make no attempt to hide their plans to have their own space defence capabilities. The absolute pre-eminence of the USA, Russia and Europe is starting to fade. For emerging countries space resources are becoming an integral component of their strategic position or an asymmetrical capability aimed at weakening the credibility of advantages held by potential rivals. This article examines the new context and the role that various countries are playing in it. It is how space policies should be determined in order to understand their politico-strategic determinants and to highlight their characteristics. Nevertheless, the competitive spirit is not the only possible way. Permanent space infrastructures could also be organised globally, as ‘global public goods’, to contribute to answering questions related to major issues facing humanity.  相似文献   

4.
Dramatic changes in the world political situation have encouraged collaboration between the main spacefaring, and other nations, in furthering progress in space endeavours. General strategic concepts must balance scientific/ technology/cost rationales while still preserving political and ambitious issues. This paper advocates optimizing the information from low-cost robotic missions to outer and inner planets when discussing ambitious robotic and manned flights to Mars. The author also articulates three additional points: first, the necessity of establishing the degree to which a human rather than a robotic presence is an absolute requirement for the most effective study of a planet; second, is the time ripe for a manned mission to Mars considering existing political/economic/technological constraints?; and third, that such a costly project is justified only if nations pool their resources and combine interests through effective international cooperation.  相似文献   

5.
As humanity prepares to extend its reach beyond low-Earth-orbit for the first time since the 1970s, a new symbol of international cooperation is needed to further promote the message of peace and collaboration such exploration entails. The space race that occurred between the USSR and the USA is an ill-suited model for long-term sustained space exploration because it is too costly and too resource-intensive for a single nation to bear. While competition is healthy for technology development, the success of a sustained space exploration strategy lies beyond technological capabilities. It lies in international cooperation, space policy, and public support. Without these, no program can realistically achieve a sustained presence in space beyond low-Earth orbit. To this effect, this paper proposes a cost-effective first step in the form of a universal symbol which, when placed alongside national flags displayed on hardware and astronaut/cosmonaut/taikonaut flight-suits, would send a strong message to the world that space exploration is done for the benefit of humanity as a whole, not just for spacefaring nations. The “Blue Marble”, the first complete picture of Earth taken from space by humans in 1972, fits this universally appealing symbol. This symbol requires no political collaboration between countries, yet is an image that anyone, anywhere in the world, can relate to regardless of nationality, ethnic origin or religious beliefs. Placed on the shoulder pads of human ’nauts – ambassadors of planet Earth – or prominently displayed on spacebound hardware, this symbol would send a universal message to present and future generations that, in space, our planet is working together for the benefit of everyone.  相似文献   

6.
Since the completion of its original prehistoric migration some 10 000 years ago, humankind has had nowhere else on Earth to go. The Space Age has produced the wherewithal for a new off-Earth human migration to restart, with the Moon as the clear initial destination. As insurance against cataclysmic and human-induced natural disasters, as a means of creating new commercial industrial–financial opportunities at a time of fundamental change in the global economy, and as a way for the USA to regain some international political influence, it should pursue Moon settlement vigorously and soon. However, the developing US space exploration program being designed by NASA for such an undertaking is too narrowly confined to the pursuit of natural-science objectives. There must be fundamental involvement of the private sector and of a much wider range of professionals and federal departments therein.  相似文献   

7.
Far-reaching social and political issues are implicit in any discussion of large-scale space development. This Viewpoint argues that the evolution of appropriate political institutions to deal with these issues is likely to be at least as important as the development of new technology. If large-scale space development is to take place, global international cooperation will be essential and such cooperation will have to be underpinned by enhanced institutional and legal structures. In the shorter term, an appropriate institutional response may be the creation of a World Space Agency. However, in the longer term, we should probably view a world space programme as falling within that class of global concerns that would be most appropriately managed by a federal world government.  相似文献   

8.
Hydrogen will assume a key role in Europe's effort to adopt its energy dependent society to satisfy its needs without releasing vast amounts of greenhouse gases. The paradigm shift is so paramount that one speaks of the “Hydrogen Economy”, as the energy in this new and ecological type of economy is to be distributed by hydrogen. However, H2 is not a primary energy source but rather an energy carrier, a means of storing, transporting and distributing energy, which has to be generated by other means.Various H2 storage methods are possible; however industries' favourite is the storage of gaseous hydrogen in high pressure tanks. The biggest promoter of this storage methodology is the automotive industry, which is currently preparing for the generation change from the fossil fuel internal combustion engines to hydrogen based fuel cells. The current roadmaps foresee a market roll-out by 2015, when the hydrogen supply infrastructure is expected to have reached a critical mass. The hydrogen economy is about to take off as being demonstrated by various national mobility strategies, which foresee several millions of electric cars driving on the road in 2020.Fuel cell cars are only one type of “electric car”, battery electric as well as hybrid cars – all featuring electric drive trains – are the others. Which type of technology is chosen for a specific application depends primarily on the involved energy storage and power requirements. These considerations are very similar to the ones in the aerospace sector, which had introduced the fuel cell already in the 1960s. The automotive sector followed only recently, but has succeeded in moving forward the technology to a level, where the aerospace sector is starting considering to spin-in terrestrial hydrogen technologies into its technology portfolio. Target areas are again high power/high energy applications like aviation, manned spaceflight and exploration missions, as well as future generation high power telecommunication satellites. Similar trends can be expected in the future for RADAR Earth Observation satellites and space infrastructure concepts of great scale.This paper examines current activities along the hydrogen value chain, both in the terrestrial and the aerospace sector. A general assessment of the synergy potential is complemented by a thorough analysis of specific applications serving as role models like a lunar manned base or pressurised rover, an aircraft APU or a high power telecommunications satellite. Potential performance improvements and cost savings serve as key performance indicators in these comparisons and trade-offs.  相似文献   

9.
While the world market for space goods and services has grown enormously and continues to do so, Russia's meagre share of it is out of all proportion to its technological and intellectual base. This was initially the fault of its rigid political system, which has made it hard for companies to adapt to a market economy. This viewpoint argues that Russia's banks, which have played a major role in the country's economic reforms, should be encouraged to invest in its space industry. In particular they could finance the ‘space education’ of the business community and fund surveys and feasibility studies. In the long term this could generate large profits and would improve their standing in the world. Ultimately they might join specialist international bank associations set up to finance cooperative ventures.  相似文献   

10.
About 100 countries now pursue their ‘public diplomacy’ interests by broadcasting audio programmes via shortwave to 400 000 000 radio listeners. However signals broadcast by surface-based shortwave transmitters are limited in coverage, reliability and quality, and shortwave broadcasting suffers from increasingly difficult operating and political problems. Space technology could now begin to be employed to create common-carrier, common-user (Intelsat- and Inmarsat-like) space-based systems which could provide a truly excellent, low-cost, direct-broadcast audio service throughout the world. The world's governments could thereby use space in a new way to promote ‘Glasnost-Openness’ for ‘the benefit of all mankind’.  相似文献   

11.
The scientific community has long embraced the concept of globalized collaboration, recognizing that scientific inquiry knows no borders and that scientific theory transcends nationality. With respect to translating scientific and technological innovation into practical application, however, national, political, and ideological barriers suddenly arise. At a time when the worlds of economics and finance are rapidly globalizing, the world of applied science lags behind — despite increasingly urgent need for global energy solutions. In the context of considering space solar power (SSP) systems, the author contends that these solutions require new ways of determining costs and benefits; that scientific experts should seek active engagement in the policy arena; and that SSP's scientific community has a critical role to play in advocating for consideration of space-based energy solutions.  相似文献   

12.
Kazuto Suzuki   《Space Policy》2007,23(2):73-80
Since its beginning the objective of Japanese space policy has been to ‘catch up’ with advanced spacefaring countries. However, this catching-up strategy is now facing several difficulties, because of the downturn in the economy and changing political and technological circumstances. In such circumstances the Japanese space community has realized the need to change its national space strategy. In 2005 a group of powerful Japanese politicians issued a report on constructing a national space strategy, which recommended that the government establish a new decision-making structure by creating a new Basic Law of Space Activities. These efforts underline the need for Japanese space to shift the focus of its policy from technological development to applications.  相似文献   

13.
China has seen a dramatic acceleration in the scope and capabilities of its space program in the past decade. This has been coupled with significantly increased global economic presence and influence as well as a steady improvement of its military capabilities. China's emergence as a major world actor has encouraged the emergence of a ‘China threat’ school of thought which interprets all Chinese policy, including its space program, as an evidence of a threatening challenge to US dominance in which the pursuit of a range of military space capabilities plays a central role. This article challenges that interpretation, arguing that China's space program is the product of a range of factors including powerful domestic political and developmental rationales and that the program is overwhelmingly driven by domestic rather than international considerations, particularly in terms of the use of the program for the purposes of enhancing prestige.  相似文献   

14.
Without doubt, humans’ most urgent need at the start of the new millennium is the continuation of economic growth, which is the only means by which the great majority of the world population can lift themselves out of the poverty in which they live. A sine qua non for continuing economic growth is for the rich countries to continue to develop new industries—as they did throughout the 20th century, thereby creating high-productivity employment for hundreds of millions of people around the world. Arguably the most significant of these thus far is the development of passenger air travel from zero in 1900 to 1.5 billion passengers per year by 2000. It is becoming clear that passenger space travel could grow to reach a similar economic scale—and that no other space activity has comparable potential. The paper describes the potential contribution to world economic growth of passenger space travel; the failure of government space agencies either to aid its development or to make a contribution to economic growth commensurate to their cost; and the value for economic policy of prioritising the realisation of passenger space travel. The faster passenger space travel services grow, the more the space industry will contribute to “Meeting the Needs of the New Millennium”.  相似文献   

15.
Dubois K 《Acta Astronautica》1991,25(8-9):605-613
"Moderne dance" (as opposed to a more academic or classical dance form) uses techniques from kinesiology, anatomy and improvization which are adapted to a cultural, technological and political environment. The function of a choreographic system is to take and give a measure of the world. This includes, with the present tendency of the evolution of culture, a new "naturalism" which seeks the secrets of the body. Dance movements express in terms of space the dimension fo the infinite. It gives somehow the measure of a world within which everything is relative. Except for the speed of light, time and space are bound together by the same principle. The qualities of body awareness and specific motricity in dancers imply--besides a strict discipline--balance, coordination, muscular performance and perfect orientation, problems that astronauts also encounter in microgravity. Could chosen exercises used in modern dance technique be applied to the training of astronauts? Dancer-choreographer Kitsou Dubois has been working in this direction since 1988. She was granted a "Villa Medicis Hors Les Murs" by the French Ministry of Foreign Affairs, to carry on with her research at NASA, Houston, Tex. in April 1989. It allowed her to investigate the reality of this analogy. She intends to evaluate the dancers' subjective vertical refering to Mittelstaedt's observations on the proportional relationship between "space sickness" and some astronauts poor evaluation of the subjective vertical. This study should create a relationship between a choreographer's empirical intuition and a scientific reality.  相似文献   

16.
Both political and scientific motives are involved in the possible re-establishment of the US-Soviet Intergovernmental Agreement on Space Cooperation. This article outlines the policy concerns which would have to be addressed in considering a new agreement, from issues of technology transfer and actual scientific benefits, to US political influence on Soviet policies. Some guidelines are offered for future cooperation, on the basis of past experience, and possible long-range cooperative projects are suggested.  相似文献   

17.
The context within which the major government space programmes of the world are planned and obtain political approval has changed dramatically with the end of the Cold War. International economic competition has become a central issue in international affairs. Economic and political constraints require that space agencies adapt the ambitious plans they put forward in the 1980s to the realities of this decade and beyond. This paper argues that in this changed context, enhanced international space cooperation can make important contributions to advancing the core interests of nations and firms, and that in some situations, increased and more intimate cooperation may be the only way to achieve ambitious space goals. The paper contains a series of policy-oriented findings and recommendations that together comprise a ‘new cooperative strategy’ for space.  相似文献   

18.
Small satellites, weighting between 100 and 200 kg, have witnessed increasing use for a variety of space applications including remote sensing constellations and technology demonstrations. The energy storage/stored power demands of most spacecraft, including small satellites, are currently accommodated by rechargeable batteries—typically nickel–cadmium cells (specific energy of 50 Wh kg−1), or more recently lithium-ion cells (150 Wh kg−1). High energy density is a primary concern for spacecraft energy storage design, and these batteries have been sufficient for most applications. However, constraints on the allowable on-board battery size have limited peak power performance such that the maximum power supply capability of small satellites currently ranges between only 70 and 200 W. This relatively low maximum power limits the capabilities of small satellites in terms of payload design and selection. In order to enhance these satellites' power performance, the research reported in this paper focused on the implementation of super-capacitors as practical rechargeable energy storage medium, and as an alternative to chemical batteries. Compared to batteries, some super-capacitors are able to supply high power at high energy-efficiency, but unfortunately they still have a very low energy density (5–30 Wh kg−1). However, the provision of this high power capability would considerably widen the range of small satellite applications.  相似文献   

19.
Satellite services benefit civil society by helping tackle challenges such as climate change, the digital divide, etc. They have the potential to deliver concrete benefits to European society through innovative services supporting economic, societal and environmental policies. Such benefits can trigger increased public support for space in Europe. However, this potential has yet to be achieved. This paper argues that technological bias, the diversity of interests and initiatives among stakeholders and their individual actions do not always serve their collective objective to ensure wide diffusion of satellite services. It draws on theories of diffusion of innovation and on its authors' participatory work with the space and the user communities and at their interface in an effort to help diffuse satellite services within civil society. One of the major causes of insufficient service diffusion is the weakness of the interface between the space and user communities; some of factors that currently contribute to this state of affairs are the space community's over-reliance on publicly financed, technical demonstration projects as solutions to service diffusion; insufficient coordination by public authorities of innovation policies and programmes with other public policies and objectives; and an insufficient integration of satellite services within users' culture, traditional tools and services. The discussion allows for conclusions to be drawn on how the system of stakeholders could function better in order for satellite services to be successfully diffused in Europe.  相似文献   

20.
《Space Policy》2014,30(4):226-230
We are witnessing a fundamental change in the perception of space-related issues. Once a symbol of technological competition between opposing political systems, space activities have become a part of everyday life and an indispensable means for states to achieve economic, scientific, political and social goals. This Report addresses the space activities of Turkey, a latecomer to space challenge but a country rapidly progressing in this field. In this context, major space-related policies and projects are first discussed. The current status of the Turkish space industry is then defined through SWOT analysis (strengths, weaknesses, opportunities, threats). The analysis is informed by a May 2012 workshop was held in Turkey at the Defense Sciences Institute, which brought together a range of interested actors to discuss Turkey's space policy. The workshop was followed up six months later with a survey of a larger group of participants. This Report lays out the findings of these two events, articulating the strengths and weaknesses for Turkey's space aspirations, and also a proposal for the country's future space ambitions. Strategies and policies that will be supportive in achieving the proposed space vision are also introduced.  相似文献   

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