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1.
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   

2.
Space at Surrey has developed over 25 years from very modest beginnings in 1974 to an international space centre by 1998. It has pioneered small satellites and succeeded in launching 14 low cost but sophisticated microsatellites over the course of two decades. In the 1990s, small satellites have become fashionable—but this was not always so! This paper describes the 25 years history of “Space at Surrey”.  相似文献   

3.
If a detection of ETI takes place, this will in all probability be the result of either: (a) detecting and recognising a signal or other emission of ETI; or (b) the finding of an alien artifact (for instance on the Moon or other Celestial Body of our Solar System); or (c) the highly improbable event of an actual encounter. First and foremost, legal consequences regarding any of these contingencies will result from immediate consultations between nations on Earth. Understandings, memoranda and even agreements might be proposed and/or concluded. Such results within the field of terrestrial law will surely be a new branch of International Law, and particularly of International Space Law. At the same time, terrestrial nations will have to realize that any ETI will be self-determined intelligent individualities or organizations who might have their own understanding of “rules of behaviour” and thus, be legal subjects. Whether one calls such rules “law” or not: if two intelligent races—both of which have specific rules of behaviour—come into contact with each other, the basic understanding of such mutual rules will lead to a kind of “code of conduct”. This might be the starting point for a kind of Law—Metalaw—between different races in the Universe.  相似文献   

4.
John C. Mankins   《Acta Astronautica》2009,65(9-10):1190-1195
The current emphasis in the US and internationally on lunar robotic missions is generally viewed as a precursor to possible future human missions to the Moon. As initially framed, the implementation of high level policies such as the US Vision for Space Exploration (VSE) might have been limited to either human lunar sortie missions, or to the testing at the Moon of concepts-of-operations and systems for eventual human missions to Mars [White House, Vision for Space Exploration, Washington, DC, 14 January, 2004. [1]]. However, recently announced (December 2006) US goals go much further: these plans now place at the center of future US—and perhaps international—human spaceflight activities a long-term commitment to an outpost on the Moon.Based on available documents, a human lunar outpost could be emplaced as early as the 2020–2025 timeframe, and would involve numerous novel systems, new technologies and unique operations requirements. As such, substantial investments in research and development (R&D) will be necessary prior to, during, and following the deployment of such an outpost. It seems possible that such an outpost will be an international endeavor, not just the undertaking of a single country—and the US has actively courted partners in the VSE. However, critical questions remain concerning an international lunar outpost. What might such an outpost accomplish? To what extent will “sustainability” be built into the outpost? And, most importantly, what will be the outpost's life cycle cost (LCC)?This paper will explore these issues with a view toward informing key policy and program decisions that must be made during the next several years. The paper will (1) describe a high-level analytical model of a modest lunar outpost, (2) examine (using this model) the parametric characteristics of the outpost in terms of the three critical questions indicated above, and (3) present rough estimates of the relationships of outpost goals and “sustainability” to LCC. The paper will also consider possible outpost requirements for near-term investments in enabling research in light of experiences in past advanced technology programs.  相似文献   

5.
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   

6.
When US President George W. Bush on 14 January 2004 announced a new US “Vision for Space Exploration”, he called for international participation in “a journey, not a race”, a call received with skepticism and concern elsewhere. But, after a slow start in implementing this directive, during 2006 NASA has increased the forward momentum of action on the program and of discussions on international cooperation in exploring “the Moon, Mars, and beyond”. There are nevertheless a number of significant top-level issues that must be addressed if a cooperative approach to human space exploration is to be pursued. These include the relationship between utilization of the ISS and the lunar exploration plans, integration of potential partners’ current and future capabilities into the exploration plans, and the evolving space-related intentions of other countries.  相似文献   

7.
Joseph N. Pelton   《Space Policy》2005,21(3):221-225
The 2003 Columbia accident demonstrated that spaceflight remains a risky and dangerous human endeavor, yet there have been few ‘unofficial’ investigations into astronaut safety. This report summarizes the findings of one such study by George Washington University's Space & Advanced Communications Research Institute—e.g. that simplicity of design may be better than complexity, that cargo missions would be better carried out robotically and that all new space transportation systems should be developed to common international standards—before examining ways that international cooperation can advance the cause of space safety. In establishing future space safety standards input from a wider range of participants (industry, universities and private research institutes, as well as space agencies, etc.) will need to be sought.  相似文献   

8.
9.
K. Anflo  R. Mllerberg 《Acta Astronautica》2009,65(9-10):1238-1249
The concept of a storable liquid monopropellant blend for space applications based on ammonium dinitramide (ADN) was invented in 1997, within a co-operation between the Swedish Space Corporation (SSC) and the Swedish Defense Research Agency (FOI). The objective was to develop a propellant which has higher performance and is safer than hydrazine. The work has been performed under contract from the Swedish National Space Board and ESA. The progress of the development has been presented in several papers since 2000.ECAPS, a subsidiary of the Swedish Space Corporation was established in 2000 with the aim to develop and market the novel “high performance green propellant” (HPGP) technology for space applications. The new technology is based on several innovations and patents w.r.t. propellant formulation and thruster design, including a high temperature resistant catalyst and thrust chamber.The first flight demonstration of the HPGP propulsion system will be performed on PRISMA. PRISMA is an international technology demonstration program with Swedish Space Corporation as the Prime Contractor.This paper describes the performance, characteristics, design and verification of the HPGP propulsion system for PRISMA. Compatibility issues related to using a new propellant with COTS components is also discussed. The PRISMA mission includes two satellites in LEO orbit were the focus is on rendezvous and formation flying. One of the satellites will act as a “target” and the main spacecraft performs rendezvous and formation flying maneuvers, where the ECAPS HPGP propulsion system will provide delta-V capability.The PRISMA CDR was held in January 2007. Integration of the flight propulsion system is about to be finalized.The flight opportunity on PRISMA represents a unique opportunity to demonstrate the HPGP propulsion system in space, and thus take a significant step towards its use in future space applications. The launch of PRISMA scheduled to 2009.  相似文献   

10.
One hundred European university students, with different interests and backgrounds, were asked to complete a questionnaire aimed at understanding their general knowledge and personal rapport with space issues and activities. Although the overall interest in space seemed to be relatively satisfactory, the data resulting from the survey—used for statistical purposes only—showed a poor awareness concerning the past, present and future of space programmes and achievements, and more generally of the economic, political and social implications of space. Stimulated and moved by the survey questions, the students interviewed showed their worries about the already developing process of division, control and commercialisation of space, underlining how the concept of education is differentiated from that of information when dealing with these issues. However, at the same time, all their statements seemed to be based on simple assumptions, preconceptions and presumptions. On the basis of the survey results, the final section of the paper reviews and discusses the present situation of space education in Europe, analysing its deficiencies and suggesting modifications, adjustments and a “step forward” that should be taken into consideration.  相似文献   

11.
The Indian Earth Observations Program, over the past three decades, has been mainly driven by the national need for natural resources management, environment monitoring and disaster support. With an array of seven Indian Earth Observation Satellites, national development support has been provided through a well-knit institutional framework of a National Natural Resources Management System (NNRMS). A wide variety of applications have been developed as an inter-agency effort over the past 15 years. Now, the capacity of the programme has extended into the global arena and is providing operational data services to the global user community. Positioning of relevant policy guidelines for the EO program to contribute to national endeavor and its transitioning for global outreaching and development of a commercial enterprise — both at national and global levels has been an area of constant attention within ISRO.Issues related to defining the space and data acquisition as a national “public ground”, costing of data products and services and evolving a commercial Earth Observation policy have been addressed for providing the overall thrust of the Indian Earth Observations program. The paper discusses the evolution of the policy in the early stages and its transition today to support a two-pronged strategy of supporting national development support and at the same time, developing a commercial program. The paper also illustrates the success of these policy endeavors through specific cases of applications and development of value added services. The paper also brings out the potential policy adjustments that will be called for in the coming years.  相似文献   

12.
The speedily expanding Internet is in the process of transforming the technological, economic, and policy bases for nation-state regulation of telecommunications, including space-based satellite networks. Deployment of the packet-switched Internet has accelerated the liberalization of telecommunications markets and has led to far-reaching regulatory restructuring and policy shifts regarding state ownership and control of networks and information flows. As space-based GMPCS networks become integral parts of the globalizing Internet infrastructure, the state-centric legal paradigm requiring state “authorization and continuing supervision” of space activities by “non-governmental entities” stipulated under Article VI of the OST and associated treaties forming the outer space legal regime will be called increasingly into question. This paper examines the technological, economic/trade, and security issues that question whether the existing state-centric paradigm for regulating Internel-based GMPCS satellite systems will remain in legal phase with emerging liberalized regulatory regimes for terrestrial Internet-based infractructures.  相似文献   

13.
John C. Mankins   《Acta Astronautica》2009,65(9-10):1208-1215
Systems that depend upon the application of new technologies inevitably face three major challenges during development: performance, schedule and budget. Technology research and development (R&D) programs are typically advocated based on argument that these investments will substantially reduce the uncertainty in all three of these dimensions of project management. However, if early R&D is implemented poorly, then the new system developments that plan to employ the resulting advanced technologies will suffer from cost overruns, schedule delays and the steady erosion of initial performance objectives. It is often critical for senior management to be able to determine which of these two paths is more likely—and to respond accordingly. The challenge for system and technology managers is to be able to make clear, well-documented assessments of technology readiness and risks, and to do so at key points in the life cycle of the program.Several approaches have been used to evaluate technology maturity and risk in order to better anticipate later system development risks. The “technology readiness levels” (TRLs), developed by NASA, are one discipline-independent, programmatic figure of merit (FOM) that allows more effective assessment of, and communication regarding the maturity of new technologies. Another broadly used management tool is of the “risk matrix”, which depends upon a graphical representation of uncertainty and consequences. However, for the most part these various methodologies have had no explicit interrelationship.This paper will examine past uses of current methods to improve R&D outcomes and will highlight some of the limitations that can arise. In this context, a new concept for the integration of the TRL methodology, and the concept of the “risk matrix” will be described. The paper will conclude with observations concerning prospective future directions for the important new concept of integrated “technology readiness and risk assessments”.  相似文献   

14.
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   

15.
Nicolas Peter   《Space Policy》2007,23(2):97-107
Science and technology (S&T) have always been at the heart of the European political construction. This started in the Cold War through a series of pan-European collaborative schemes in a panoply of different scientific fields like molecular biology and nuclear research. However, while most of these early collaborative patterns focused on intra-European cooperation, in the post-Cold War era international S&T relations have evolved to encompass a broader international dimension. The European Union is now building a diverse and robust network of cooperation with non-EU partners to become a centre of gravity in international S&T affairs. This increasing linkage between S&T and foreign policy is particularly explicit in space activities. Even though it is the newest space actor in Europe, the EU is pushing the continent to extend the scope of its partnerships with Russia and China, while at the same time modifying its relations with the traditional European partner, the USA, illustrating therefore the emergence of a distinct “EU space diplomacy”.  相似文献   

16.
Why we need a space elevator   总被引:2,自引:1,他引:1  
The goals of and vision for development of a space elevator have been discussed repeatedly. However, why we should develop one has been glossed over. This paper will focus upon the major issue—why build a space elevator infrastructure? It considers why we need a space elevator, what missions it would enable and how far it would reduce costs. There is no doubt that some major missions would be enhanced or significantly enabled by a space elevator infrastructure. Global communications, energy, monitoring of the Earth, global/national security, planetary defense, and exploration beyond low-Earth orbit are a few examples. In the end, if we are serious about extending space development and avoiding limitations on the human spirit, the reason we should build a space elevator is because we must!  相似文献   

17.
Through a techno-nationalist lens, this paper will assess the growing China–European Union (EU) space partnership, and its implications for international space cooperation and competition. Techno-nationalism (jishu minzuzhuyi), the idea that technological strength is an effective determinant of national power in a harshly competitive world,3 informs both Chinese and US perceptions of China's space development. Using this lens elevates all space activities—manned, unmanned, military and scientific—to the strategic level. It is our contention that because of the increasing China–EU space partnership, the USA must re-evaluate its approach to China—away from the containment approach, which has thus far predominated, toward an approach which would offer the USA the opportunity to influence and, thereby, decrease the importance of the emerging partnership.  相似文献   

18.
In announcing a new Vision for the US space program, President George Bush committed the USA to “a long-term human and robotic program to explore the solar system”, via a return to the Moon, leading to exploration of Mars and other destinations. He also stated that other nations would be invited to join the vision. Many other nations have, or are developing, ‘exploration visions’ of their own. The potential for international cooperation therefore exists, both at the vision and program/project levels. This paper, based on Working Group discussions as part of an AIAA space cooperation workshop,1 presents an approach for maximizing the return on all global investments in space exploration. It proposes an international coordination mechanism through which all these various national activities could be integrated into an inherently global enterprise for space exploration, a ‘virtual program of programs’. Within the context of the coordination, individual activities would utilize the full range of cooperative mechanisms for implementation. A significant benefit of this mode of conducting cooperation is that it would not require the negotiation of complex overarching international agreements as a precondition for initiating international activity.  相似文献   

19.
The special theory of relativity rests on the assumption that in no case can the speed of light be exceeded. Rather surprisingly, however, recent advances in the general theory of relativity show that Faster-Than-Light (FTL) travel is allowed by Einstein’s gravitational theory. An explanation of this apparent contrast between special and general relativity lies in the fact that general relativity uses non-linear differential equations and non-Euclidean spacetime geometry that special relativity does not. Therefore, this larger mathematical armoury makes room for a whole new class of very subtle and unexpected relativistic phenomena to come to light. One of these is the Theory of Wormholes, more politely termed Tunnels into Space–Time. In 1988, Kip S. Thorne and Michael S. Morris published a path-breaking paper about Wormholes showing how spaceflight between two stars might be possible in a time of hours if a “tunnel” dug into space–time exists between them. However, they also showed that keeping the tunnel open for the spaceship to travel through would require a kind of matter, called “exotic” by them, that does not appear to exist in nature, because its tensional strength would have to exceed the energy density of its matter. This request is a severe constraint to the natural existence of Morris–Thorne Wormholes, or even to their artificial construction by an advanced civilization. In 1995, however, the present author sought to replace the exotic matter in a Morris–Thorne Wormhole by a very intense magnetic field. Such “Magnetic Wormholes” could indeed exist because very intense magnetic fields are already known to exist on the surface of neutron stars and pulsars. This paper discusses the consequences on SETI of the possible existence of Magnetic Wormholes. Phenomena of divergent gravitational lensing might possibly occur in the proximity of pulsars and neutron stars. These effects could help us detect signals from very far civilisations by virtue of ordinary SETI techniques already in use.  相似文献   

20.
Technology readiness assessments: A retrospective   总被引:1,自引:0,他引:1  
John C. Mankins   《Acta Astronautica》2009,65(9-10):1216-1223
The development of new system capabilities typically depends upon the prior success of advanced technology research and development efforts. These systems developments inevitably face the three major challenges of any project: performance, schedule and budget. Done well, advanced technology programs can substantially reduce the uncertainty in all three of these dimensions of project management. Done poorly, or not at all, and new system developments suffer from cost overruns, schedule delays and the steady erosion of initial performance objectives. It is often critical for senior management to be able to determine which of these two paths is more likely—and to respond accordingly. The challenge for system and technology managers is to be able to make clear, well-documented assessments of technology readiness and risks, and to do so at key points in the life cycle of the program.In the mid 1970s, the National Aeronautics and Space Administration (NASA) introduced the concept of “technology readiness levels” (TRLs) as a discipline-independent, programmatic figure of merit (FOM) to allow more effective assessment of, and communication regarding the maturity of new technologies. In 1995, the TRL scale was further strengthened by the articulation of the first definitions of each level, along with examples (J. Mankins, Technology readiness levels, A White Paper, NASA, Washington, DC, 1995. [1]). Since then, TRLs have been embraced by the U.S. Congress’ General Accountability Office (GAO), adopted by the U.S. Department of Defense (DOD), and are being considered for use by numerous other organizations. Overall, the TRLs have proved to be highly effective in communicating the status of new technologies among sometimes diverse organizations.This paper will review the concept of “technology readiness assessments”, and provide a retrospective on the history of “TRLs” during the past 30 years. The paper will conclude with observations concerning prospective future directions for the important discipline of technology readiness assessments.  相似文献   

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