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1.
Since 1958, the UN Committee on the Peaceful Uses of Outer Space (COPUOS) has been an international forum working to build a body of space law by universal consensus, a method of working which has been essential to ensuring the enforce-ability of its decisions. This consensus has degenerated in recent years, slowing the progress of space law — which has now fallen dangerously behind the development of space technology. Some important recent decisions have had to be taken by majority voting rather than consensus, to overcome the paralysis of COPUOS. This, however, can only be a temporary solution. The author makes an urgent plea for a return to COPOUS and its methods.  相似文献   

2.
首先对"十五"期间中国在空间碎片研究领域取得的主要进展进行了综述,涉及空间碎片监测预警、航天器防护和空间碎片减缓三个方面;然后对"十一五"期间中国空间碎片研究的主要内容进行了介绍。  相似文献   

3.
European space activities began in the 1960's. The development of what was initially scientific research and which later spread to the enthusiastic involvement of Europe's most advanced industry is by now familiar history. The organization of ELDO and ESRO, which eventually gave way to today's ESA, occured in a span of less than a decade. Many major European countries also commenced their national space programmes during this period. This report examines the space initiatives taken by Italian industry.  相似文献   

4.
At its 1996/1997 session, the UN General Assembly adopted by consensus Resolution 51/122, containing a Declaration on international cooperation in space. This Declaration finalizes the agenda item which has become known as ‘Space Benefits’ in the UNCOPUOS Legal Subcommittee. It provides an authoritative interpretation of the cooperation principle in Article I of the Outer Space Treaty and should thereby put an end to North-South confrontation over the question of shaping the international order for space activities. This article traces the history of the run-up to adoption of the Resolution, analyses how it came to be accepted by all sides and examines its likely impact.  相似文献   

5.
Human space exploration since Apollo appears to lack an overall context. There has been an overall context for the world's space efforts. But it is an unofficial one and it is outmoded, because it was based on a false assumption. This is the space exploration plan articulated by Von Braun in the 1950s and restated as the Integrated Space Program - 1970–1990, whose principal aim is to send humans to explore Mars. The critical underlying assumption of this plan was that Mars is a planet much like Earth, with an active biosphere. This Program has persisted nearly two decades after this underlying assumption has been shown to be false. There is a competing context re-emerging for human space exploration and development which is better fitted to the needs of human society in the post-Cold War era than the Mars program embraced by NASA and, to a large extent, the USSR during the period of US-Russian competition. The original space program uses the resources of free space and provides an economic rationale for human space activity.  相似文献   

6.
In long term space flight, the mechanical forces applied to the skeleton are substantially reduced and are altered in character. This reduced skeletal loading results in a reduction in bone mass. Exercise techniques currently used in space can maintain muscle mass but the mechanical stimulus provided by this exercise does not prevent bone loss. By applying an external impulsive load for a short period each day, which is intended to mimic the heel strike transient, to the lower limb of an astronaut during a long term space flight (5 months), this study tests the hypothesis that the bone cells can be activated by an appropriate external mechanical stimulus to maintain bone mass throughout prolonged periods of weightlessness. A mechanical loading device was developed to produce a loading of the os-calcis similar to that observed during the heel strike transient. The device is activated by the astronaut to provide a transient load to the heel of one leg whilst providing an equivalent exercising load to the other leg. During the EUROMIR95 mission on the MIR space station, an astronaut used this device for a short period daily throughout the duration of the mission. Pre- and post-flight measurements of bone mineral density (BMD) of the os-calcis and femoral neck of the astronaut were made to determine the efficacy of the device in preventing loss of bone mineral during the mission. On the os-calcis which received the mechanical stimulus, BMD was maintained throughout the period of the flight, while it was reduced by up to 7% on the os-calcis which received no stimulus. Post-flight, BMD in both the stimulated and non-stimulated os-calcis reduces, the extent of this reduction however is less in the stimulated os-calcis. For the femoral neck, the mechanical stimulation does not produce a positive effect.  相似文献   

7.
While the need for adequate space law may be as urgent as ever, the international community has discovered that today it is increasingly difficult to reach consensus on statutes to govern new space activities. In view of the noticeable slowdown in the law-making process, serious discussions about the most suitable and effective techniques of space legislation are required. The author discusses the political and legal problems of making laws to deal with space and space activities. A number of suggestions aimed at improving the present legislative process are formulated.  相似文献   

8.
空间科学不仅能够推动我国在基础科学研究领域取得重大科学突破,还能够有效牵引、带动航天高新技术的发展。中国科学院空间科学战略性先导科技专项是"十二五"时期我国空间科学领域最重要的系统性进展,开启了中国空间科学发展的新篇章。"十三五"时期,我国将继续研制、发射一系列新的空间科学卫星,这对航天运输系统提出了新的技术发展需求。发展空间科学必将推动我国的航天强国、世界科技强国建设进程。  相似文献   

9.
Jana Robinson   《Space Policy》2011,27(1):27-37
Transparency and confidence-building measures (TCBMs) are a set of tools designed to display, predict and discipline states’ behaviour with respect to maintaining the security of space. With intentional and unintentional threats to the peaceful use of space on the rise, there is a growing international consensus on the need for greater transparency in space-related activities as well as confidence-building measures to reduce the prospects of disruption to the ever-expanding role of space in our day-to-day lives. Terrestrial TCBMs can serve as a guide to understanding what political arrangements are possible in space, including certain precedents in the areas of arms control, non-proliferation and disarmament. At the same time, current and emerging challenges in space - including orbital space debris, risk of collisions, growing saturation of the radiofrequency spectrum, the crowding of satellites in geostationary (GEO) orbit and threat of purposeful disruption - need to be evaluated in the context of unilateral, bilateral, multilateral and private initiatives to increase space situational awareness and security. This paper describes and evaluates various prospective TCBMs alongside current proposals to advance safety and security in space, including the EU Draft Code of Conduct for Outer Space Activities. It offers specific recommendations, arguing that Europe is uniquely qualified to negotiate a 21st century TCBM architecture thanks to its history of diplomacy and ability to identify common ground among disparate parties. This will only happen, however, with a more defined institutional design and the EU’s emergence as a global civilian leader.  相似文献   

10.
This paper assesses the impacts that changes in the US presidency have had on the civilian space program during the post-Apollo period. It suggests that the White House has lost influence over space issues relative to other interested sectors. The primary factors causing this are a long-term shift to lower priority for these issues, and an inevitable widening of the scope of influence over this sector of activity. Key post-Apollo decisions are discussed for their substantive content and also for what they reveal about the extent to which the president chose to be involved. These findings have implications across all science and technology issue areas as the USA, in the aftermath of the Cold War, reexamines its post-World War II social contract with science.  相似文献   

11.
The activity of the enzymes involved in aminoacid metabolism (tyrosine aminotransferase, TAT, tryptophan pyrrolase TP, serine dehydratase, SD) with rapid response to glucocorticoids and enzymes requiring for activity increase repeated administration of corticosterone (alanine aminotransferase, ALT, aspartate aminotransferase, AST) in liver, the changes of lipolysis in adipose tissue and the plasma corticosterone levels were studied in rats subjected to space flight (F), in animals from synchron model experiments (SM, simulated conditions of space flight in laboratory) and in intact controls (C). The increase of plasma corticosterone concentration and of the activity of rapidly (TAT, TP, SD) and slowly activating enzymes (ALT, AST) was found in F group 6-10 hr after space flight (18.5 days on biosatellite COSMOS 1129). This suggested the presence of acute-stress (associated primarily with the landing) and chronic stress induced hypercorticosteronemia during the flight. After the short 6-day period of recovery the plasma corticosterone concentrations and the activities of liver enzymes returned to control levels. The exposition of animals to repeated immobilization stress showed higher response of corticosterone levels in flight rats as compared to intact controls. No changes in basal lipolysis were observed in flight rats in comparison to intact controls, however the stimulation of lipolysis by norepinephrine was lower in animals from F and SM groups. This lower response of lipolytic processes to norepinephrine was found in flight animals also after six days period of recovery. These results showed that there are important changes in the regulation of lipolytic processes in adipose tissue of rats after space flight and in the conditions of model experiments.  相似文献   

12.
In the coming decades, as we continue our path of space exploration beyond the Earth's orbit, we will be required to provide sound medical and surgical care for the safety of space travellers and spaceflight participants. A few investigations have taken place in the field of surgery in space. In this paper, the authors review the present literature in order to identify possible limitations that currently exist and that could impair our ability to provide surgical care during spaceflight, from the pre-operative to the post-operative period.  相似文献   

13.
The activity of the sympathetic adrenal system in cosmonauts exposed to a stay in space lasting for about half a year has so far been studied only by measuring catecholamine levels in plasma and urine samples taken before space flight and after landing. The device "Plasma 01", specially designed for collecting and processing venous blood from subjects during space flight on board the station Salyut-7 rendered it possible for the first time to collect and freeze samples of blood from cosmonauts in the course of a long-term 237-day space flight. A physician-cosmonaut collected samples of blood and urine from two cosmonauts over the period of days 217-219 of their stay in space. The samples were transported to Earth frozen. As indicators of the sympathetic adrenal system activity, plasma and urine concentrations of epinephrine and norepinephrine as well as urine levels of the catecholamine metabolites metanephrine, normetanephrine, and vanillylmandelic acid were determined before, during and after space flight. On days 217-219 of space flight plasma epinephrine and norepinephrine levels were slightly increased, yet not substantially different from normal. During stress situations plasma norepinephrine and epinephrine levels usually exhibit a manifold increase. On days 217-219 of space flight norepinephrine and epinephrine levels in urine were comparable with pre-flight values and the levels of their metabolites were even significantly decreased. All the parameters studied, particularly plasma norepinephrine as well as urine norepinephrine, normetanephrine, and vanillylmandelic acid, reached the highest values 8 days after landing. The results obtained suggest that, in the period of days 217-219 of the cosmonauts stay in space in the state of weightlessness, the sympathetic adrenal system is either not activated at all or there is but a slight activation induced by specific activities of the cosmonauts, whereas in the process of re-adaptation after space flight on Earth this system is considerably more markedly activated.  相似文献   

14.
Overview of the legal and policy challenges of orbital debris removal   总被引:1,自引:1,他引:1  
Brian Weeden   《Space Policy》2011,27(1):38-43
Much attention has been paid recently to the issue of removing human-generated space debris from Earth orbit, especially following conclusions reached by both NASA and ESA that mitigating debris is not sufficient, that debris-on-debris and debris-on-active-satellite collisions will continue to generate new debris even without additional launches, and that some sort of active debris removal (ADR) is needed. Several techniques for ADR are technically plausible enough to merit further research and eventually operational testing. However, all ADR technologies present significant legal and policy challenges which will need to be addressed for debris removal to become viable. This paper summarizes the most promising techniques for removing space debris in both LEO and GEO, including electrodynamic tethers and ground- and space-based lasers. It then discusses several of the legal and policy challenges posed, including: lack of separate legal definitions for functional operational spacecraft and non-functional space debris; lack of international consensus on which types of space debris objects should be removed; sovereignty issues related to who is legally authorized to remove pieces of space debris; the need for transparency and confidence-building measures to reduce misperceptions of ADR as anti-satellite weapons; and intellectual property rights and liability with regard to ADR operations. Significant work on these issues must take place in parallel to the technical research and development of ADR techniques, and debris removal needs to be done in an environment of international collaboration and cooperation.  相似文献   

15.
Russia has gained a lot of experience in operating the space suits (SS) during the extravehicular activities (EVA) by the crews of SALYUT-6, SALYUT-7 and MIR orbiting stations. A total of 21 Orlan-type space suits of various models were operated onboard the orbiting stations (OS) during almost 20 years period. Some of these space suits served up to 3 years in orbit. The paper reviews special features of long SS operation (without return to the Earth) onboard an orbiting station as well as the problems associated with SS repeated use by several crews. An analysis of measures to support solving of the problems of SS long stay and reliable operation onboard the orbiting station is made: selection of a corresponding SS type and separate elements design; selection of the materials; routine and preventive maintenance; development tests. The advantages of the space suit of a semi-rigid type for solving the above problems are shown. The paper includes a short analysis of space suits' operation onboard the Russian orbiting station MIR, and some restuts of inspection of the Orlan-DMA space suit returned to the Earth from orbit by STS-79 alter long operation in orbit. Recommendations on further improvement of the space suits for EVA operations in the International Space Station (ISS) are given.  相似文献   

16.
采用对比分析方法研究空间与地面、不同工况、不同累计工作时间段的离子推力器非预期电击穿特性变化,获得了离子推力器击穿频次与其主要影响因素之间的关联性.研究结果表明:在地面试验和空间飞行的全任务周期中,推力器击穿频次都呈现出早期较高、然后快速降低并保持长期稳定的基本特点;空间飞行应用中的平均击穿频次普遍比地面试验中的低1~...  相似文献   

17.
A primary objective of the International Space Station is to provide a long-term quiescent environment for the conduct of scientific research for a variety of microgravity science disciplines. Since continuous human presence on the space station began in November 2000 through the end of Increment-6, over 1260 hours of crew time have been allocated to research. However, far more research time has been accumulated by experiments controlled on the ground. By the end of the time period covered by this paper (end of Increment-6), the total experiment hours performed on the station are well over 100,000 hours (Expedition 6 Press Kit: Station Begins Third Year of Human Occupation, Boeing/USA/NASA, October 25, 2002). This paper presents the results of the on-going effort by the Principal Investigator Microgravity Services project, at NASA Glenn Research Center, in Cleveland, Ohio, to characterize the microgravity environment of the International Space Station in order to keep the microgravity scientific community apprised of the reduced gravity environment provided by the station for the performance of space experiments. This paper focuses on the station microgravity environment for Increments 5 and 6. During that period over 580 Gbytes of acceleration data were collected, out of which over 34,790 hours were analyzed. The results presented in this paper are divided into two sections: quasi-steady and vibratory. For the quasi-steady analysis, over 7794 hours of acceleration data were analyzed, while over 27,000 hours were analyzed for the vibratory analysis. The results of the data analysis are presented in this paper in the form of a grand summary for the period under consideration. For the quasi-steady acceleration response, results are presented in the form of a 95% confidence interval for the station during "normal microgravity mode operations" for the following three attitudes: local vertical local horizontal, X-axis perpendicular to the orbit plane and the Russian torque equilibrium attitude. The same analysis was performed for the station during "non-microgravity mode operations" to assess the station quasi-steady acceleration environment over a long period of time. The same type of analysis was performed for the vibratory, but a 95th percentile benchmark was used, which shows the overall acceleration magnitude during Increments 5 and 6. The results, for both quasi-steady and vibratory acceleration response, show that the station is not yet meeting the microgravity requirements during the microgravity mode operations. However, it should be stressed that the requirements apply only at assembly complete, whereas the results presented below apply up to the station's configuration at the end of Increment-6.  相似文献   

18.
《Acta Astronautica》2007,60(4-7):460-471
This study identifies genes that determine survival during a space flight, using the model eukaryotic organism, Saccharomyces cerevisiae. Select strains of a haploid yeast deletion series grew during storage in distilled water in space, but not in ground based static or clinorotation controls. The survival advantages in space in distilled water include a 133-fold advantage for the deletion of PEX19, a chaperone and import receptor for newly- synthesized class I peroxisomal membrane proteins, to 77–40 fold for deletion strains lacking elements of aerobic respiration, isocitrate metabolism, and mitochondrial electron transport. Following automated addition of rich growth media, the space flight was associated with a marked survival advantage of strains with deletions in catalytically active genes including hydrolases, oxidoreductases and transferases. When compared to static controls, space flight was associated with a marked survival disadvantage of deletion strains lacking transporter, antioxidant and catalytic activity. This study identifies yeast deletion strains with a survival advantage during storage in distilled water and space flight, and amplifies our understanding of the genes critical for survival in space.  相似文献   

19.
The exploration of space is a long-term endeavor that will require strong public support to weather societal and political changes over the period of its implementation. In August 2006, George Mason University's Center for Aerospace Policy Research organized a workshop to address this issue. The sustainability of space exploration was investigated from a variety of perspectives by invited experts from the space sector as well as from the market research and public relations fields. This paper summarizes the results of the workshop. It presents market research data along with recommendations for an active strategic communications effort as well as public engagement to enhance public support for space exploration, especially among the younger age groups which tend to be uninterested in space activities.  相似文献   

20.
Two bed rest analog studies of space flight were performed; one 14 d and the other 28 d in duration. Exercise response was studied in detail during the 28 d study and following both the 14 d and 28 d studies. This paper relates the results of these studies to physiologic changes noted during and following space flight. The most consistent change noted after both bed rest and space flight is an elevated heart rate during exercise. A second consistent finding is a postflight or postbed rest reduction in cardiac stroke volume. Cardiac output changes were variable. The inability to simulate inflight activity levels and personal exercise makes a direct comparison between bed rest and the results from specific space flights difficult.  相似文献   

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