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1.
In the space experiment "Molecular adaptation strategies of microorganisms to different space and planetary UV climate conditions" (ADAPT), bacterial endospores of the highly UV-resistant Bacillus subtilis strain MW01 were exposed to low-Earth orbit (LEO) and simulated martian surface conditions for 559 days on board the European Space Agency's exposure facility EXPOSE-E, mounted outside the International Space Station. The survival of B. subtilis MW01 spores from both assays (LEO and simulated martian conditions) was determined by a colony-formation assay after retrieval. It was clearly shown that solar extraterrestrial UV radiation (λ≥110?nm) as well as the martian UV spectrum (λ≥200?nm) was the most deleterious factor applied; in some samples only a few spore survivors were recovered from B. subtilis MW01 spores exposed in monolayers. However, if shielded from solar irradiation, about 8% of MW01 spores survived in LEO conditions, and 100% survived in simulated martian conditions, compared to the laboratory controls. The results demonstrate the effect of shielding against the high inactivation potential of extraterrestrial solar UV radiation, which limits the chances of survival of even the highly UV-resistant strain of B. subtilis MW01 in the harsh environments of outer space and the martian surface.  相似文献   

2.
This article presents a typology of extraterrestrial signals which demonstrates the possibilities of very complex social and psychological reactions to the receipts of a message from outer space, and also helps to address the problem of signal detection. The author argues that there is a clear need to establish a Contact Verification and Interpretation Committee. A great deal of planning and forethought is necessary if we are to assure the smoothest possible social assimilation of the news that another intelligence has been detected.  相似文献   

3.
Cryptoendolithic microbial communities and epilithic lichens have been considered as appropriate candidates for the scenario of lithopanspermia, which proposes a natural interplanetary exchange of organisms by means of rocks that have been impact ejected from their planet of origin. So far, the hardiness of these terrestrial organisms in the severe and hostile conditions of space has not been tested over extended periods of time. A first long-term (1.5 years) exposure experiment in space was performed with a variety of rock-colonizing eukaryotic organisms at the International Space Station on board the European EXPOSE-E facility. Organisms were selected that are especially adapted to cope with the environmental extremes of their natural habitats. It was found that some-but not all-of those most robust microbial communities from extremely hostile regions on Earth are also partially resistant to the even more hostile environment of outer space, including high vacuum, temperature fluctuation, the full spectrum of extraterrestrial solar electromagnetic radiation, and cosmic ionizing radiation. Although the reported experimental period of 1.5 years in space is not comparable with the time spans of thousands or millions of years believed to be required for lithopanspermia, our data provide first evidence of the differential hardiness of cryptoendolithic communities in space.  相似文献   

4.
This article analyses established models of imperialism and seeks to apply them to possible space development scenarios. Inherent in such an analysis is a critique of the predominant rationales for advanced Solar System development (permanent planetary bases, settlements and colonies). The argument that emerges suggests that no single rationale is sufficiently strong to propel humans towards Solar System expansion as yet. However, in the instance that an extraterrestrial material becomes economically valuable, Solar System development will probably proceed. Under this scenario the present politico-legal regimes which govern prospective space development (and, moreover, the philosophical inclinations of many of those involved in formulating such regimes) dictate that Solar System development will be of an imperialistic nature.  相似文献   

5.
Traditionally cited benefits such as scientific and economic progress or political advantages have been widely recognized as insufficient to justify ongoing and future human spaceflight programmes in today's prevailing geopolitical and socioeconomic environment. A rationale for human spaceflight evoking visions such as exploitation of extraterrestrial resources and human exploration of space has to cope with an unavoidable dilemma: attractive as they may appear, those projects are fraught with many grave uncertainties and risks. The paper attempts to answer the question of which significance (if any) such visionary projects may assume in justifying the continuation of human spaceflight activities. We argue that, despite as yet unanswerable technological and economic questions and despite the extremely long time-frames involved, it seems reasonable and, hence, justified to keep the option alive to be able to solve — by means of humans in space — one of humankind's probable major problems in the coming century: the impending energy crisis.  相似文献   

6.
The Space Age is causing new applications to the concept of culture, a human coping tool. The exploration and exploitation of outer space resources are altering human culture both on Earth and in orbit. For the first time in history, our species need not merely react and adapt to environment, but plan for a space culture appropriate for extraterrestrial migration. The impact of culture can be analyzed in terms of how space developments alter human perceptions and behavior on this planet; the emergence of a new culture to suit the orbital environment; the organizations that build spacecraft and deploy people aloft; and the technological systems created for spacefaring. This article presents a paradigm for analyzing some of the non-technical human factors involved in space undertakings. It also offers a method for classifying a culture according to ten categories which may be applied both to a macroculture, such as a lunar base; or a microculture, such as a space agency or crew. Human enterprise in space is viewed as both altering the species, and providing a challenge for expanded behavioral and biological scientific research on living and working in space.  相似文献   

7.
Spore-forming bacteria are of particular concern in the context of planetary protection because their tough endospores may withstand certain sterilization procedures as well as the harsh environments of outer space or planetary surfaces. To test their hardiness on a hypothetical mission to Mars, spores of Bacillus subtilis 168 and Bacillus pumilus SAFR-032 were exposed for 1.5 years to selected parameters of space in the experiment PROTECT during the EXPOSE-E mission on board the International Space Station. Mounted as dry layers on spacecraft-qualified aluminum coupons, the "trip to Mars" spores experienced space vacuum, cosmic and extraterrestrial solar radiation, and temperature fluctuations, whereas the "stay on Mars" spores were subjected to a simulated martian environment that included atmospheric pressure and composition, and UV and cosmic radiation. The survival of spores from both assays was determined after retrieval. It was clearly shown that solar extraterrestrial UV radiation (λ≥110?nm) as well as the martian UV spectrum (λ≥200?nm) was the most deleterious factor applied; in some samples only a few survivors were recovered from spores exposed in monolayers. Spores in multilayers survived better by several orders of magnitude. All other environmental parameters encountered by the "trip to Mars" or "stay on Mars" spores did little harm to the spores, which showed about 50% survival or more. The data demonstrate the high chance of survival of spores on a Mars mission, if protected against solar irradiation. These results will have implications for planetary protection considerations.  相似文献   

8.
The proposed space experiments BOSS (Biofilm Organisms Surfing Space) and BIOMEX (BIOlogy and Mars experiment) will take place on the space exposure facility EXPOSE-R2 on the International Space Station (ISS), which is set to be launched in 2014. In BOSS the hypothesis to be tested is that microorganisms grown as biofilms, hence embedded in self-produced extracellular polymeric substances, are more tolerant to space and Martian conditions compared to their planktonic counterparts. Various microbial biofilms have been developed including those obtained from the cyanobacterium Chroococcidiopsis isolated from hot and cold deserts. The prime objective of BIOMEX is to evaluate to what extent biomolecules are resistant to, and can maintain their stability under, space and Mars-like conditions; therefore a variety of pigments and cell components are under investigation to establish a biosignature data base; e.g. a Raman spectral library to be used for extraterrestrial life biosignatures. The secondary objective of BIOMEX is to investigate the endurance of extremophiles, focusing on their interactions with Lunar and Martian mineral analogues. Ground-based studies are currently being carried out in the framework of EVTs (Experiment Verification Tests) by exposing selected organisms to space and Martian simulations. Results on a desert strain of Chroococcidiopsis obtained from the first set of EVT, e.g. space vacuum, Mars atmosphere, UVC radiation, temperature cycles and extremes, suggested that dried biofilms exhibited an enhanced survival compared to planktonic lifestyle. Moreover the protection provided by a Martian mineral analogue (S-MRS) to the sub-cellular integrities of Chroococcidiopsis against UVC radiation supports the endurance of this cyanobacterium under extraterrestrial conditions and its relevance in the development of life detection strategies.  相似文献   

9.
《Acta Astronautica》2007,60(4-7):588-593
The paper discusses concepts about the role of architecture in the design of space habitats and the development of a general evaluation criteria of architectural design contribution. Besides the existing feasibility studies, the general requisites, the development studies, and the critical design review which are mainly based on the experience of human space missions and the standards of the NASA-STD-3000 manual and which analyze and evaluate the relation between man and environment and between man and machine mainly in its functionality, there is very few material about design of comfort and wellbeing of man in space habitat. Architecture for space habitat means the design of an artificial environment with much comfort in an “atmosphere” of wellbeing. These are mainly psychological effects of human factors which are very important in the case of a long time space mission. How can the degree of comfort and “wellbeing atmosphere” in an artificial environment be measured? How can the quality of the architectural contribution in space design be quantified? Definition of a criteria catalogue to reach a larger objectivity in architectural design evaluation. Definition of constant parameters as a result of project necessities to quantify the quality of the design. Architectural design analysis due the application and verification within the parameters and consequently overlapping and evaluating results. Interdisciplinary work between architects, astronautics, engineers, psychologists, etc. All the disciplines needed for planning a high quality habitat for humans in space. Analysis of the principles of well designed artificial environment. Good quality design for space architecture is the result of the interaction and interrelation between many different project necessities (technological, environmental, human factors, transportation, costs, etc.). Each of this necessities is interrelated in the design project and cannot be evaluated on its own. Therefore, the design process needs constant check ups to choose each time the best solution in relation to the whole. As well as for the main disciplines around human factors, architectural design for space has to be largely tested to produce scientific improvement.  相似文献   

10.
With recently growing interest in the Active Search for Extraterrestrial Intelligence (SETI), in which humankind would send intentional signals to extraterrestrial civilizations, there have been increased concerns about appropriate policy, as well as the role of space law and ethics in guiding such activities. Implicit in these discussions are notions of responsibility and capability that affect judgments about whether humans or other civilizations should initiate transmissions. Existing protocols that guide SETI research address transmissions from Earth, but there is debate over whether these guidelines should inform de novo transmissions as well. Relevant responsibilities to address include (1) looking out for the interests of humankind as a whole, (2) being truthful in interstellar messages, and (3) benefiting extraterrestrial civilizations. Our capabilities as a species and a civilization affect how well we can fulfill responsibilities, as seen when we consider whether we will be able to reach consensus about message contents (and whether that would be desirable), and whether we have the capacity to decode messages from beings that rely on different sensory modalities. The interplay of these responsibilities and capabilities suggests that humankind should place increased emphasis on Active SETI.  相似文献   

11.
Deliberate and unintentional radio transmissions from Earth propagate into space. These transmissions could be detected by extraterrestrial watchers over interstellar distances. This article analyzes the harm and benefits of deliberate and unintentional transmissions relevant to Earth and humanity. Comparing the magnitude of deliberate radio broadcasts intended for messaging to extraterrestrial intelligence (METI) with the background radio spectrum of Earth, we find that METI attempts to date have much lower detectability than emissions from current radio communication technologies on Earth. METI broadcasts are usually transient and several orders of magnitude less powerful than other terrestrial sources, such as astronomical and military radars, which provide the strongest detectable signals. The benefits of radio communication on Earth most probably outweigh the potential harm of detection by extraterrestrial watchers; however, the uncertainty regarding the outcome of contact with extraterrestrial beings creates difficulty in assessing whether or not to engage in long-term and large-scale METI.  相似文献   

12.
The Moon landings of the Apollo programme irrevocably changed the way we see ourselves. Most significantly, this was the first time that humans had set foot on a celestial body other than Earth. The program has left a number of sites on the Moon as well as on Earth. While the management of the sites and artefacts on Earth is fairly straightforward as they are subject to national heritage legislation, it is not so simple with the sites and artefacts on the lunar surface. Moreover, the sites on the Moon differ in one unique aspect from all other heritage sites on Earth: the absence of a lunar atmosphere of any note means that all foot- and track prints of the astronauts are preserved providing a total record of the pioneering phases of human exploration of the Moon. The nascent developments of space tourism, including proposals for lunar heritage tourism, however, threaten the preservation of these traces on the Moon. This paper discusses the terrestrial and in particular the extraterrestrial heritage of the Apollo programme. Set out are the management ethics that need to apply on the lunar surface if this unique heritage is to have a future.  相似文献   

13.
The design presented in this paper is in response to the revolution in private space activities, the increasing public interest in commercial flights to space and the utilization of structures such as space hotels or private orbital habitats. The baseline for the Omicron design concept is the Russian Salyut derived space station module. Salyut was the first space station to orbit the Earth. Its unique design and technical features were what made the development of space stations Salyut 1–7, MIR and the International Space Station (ISS) Zwezda service module possible. Due to its versatility and the reliable operating launch vehicle Proton, this space module series has the potential to be adapted for space hotel development. This paper proposes a conceptual design of the space habitat called Omicron, with particular focus on interior design for the microgravity environment. The Omicron concepts address the needs of space tourism with a strong emphasis on the safety and comfort of the spaceflight participants. The Omicron habitat supports three inhabitants in nominal conditions (e.g., two passengers and one astronaut). The habitat provides a flexible interior, facilities and spaces dynamically transforming in order to accommodate various types of activities, which will be performed in an organically formed interior supporting spatial orientation and movement in microgravity. The future development potential of Omicron is also considered. The baseline version is composed solely of one rigid module with an inverted cupola for observations. An alternative version offers more space using an inflatable structure. Finally, a combination of multiple Omicron modules enables the creation of a larger orbital habitat. The Omicron's subsystems support a few days visit by trained passengers. The transport to the habitat would be provided e.g., by the Soyuz TMA spacecraft carried by the Soyuz launch vehicle in the early stage of Omicron's development, before a fully reusable spacecraft would be available.  相似文献   

14.
This study presents a new approach to the concept of cosmic consciousness integrated in current neuroscience knowledge and discusses implications for the search for extraterrestrial intelligence. It also examines different aspects related to consciousness and how it may play a key role in the understanding of the search for extraterrestrial intelligence and life in the Universe and its implications. Subjects (n=116) were college students from Spain, the United States, and Italy. Subjects responded to a questionnaire comprising five different sections: (A) religious beliefs, (B) environment and general opinion, (C) astronomy, (D) contact, and (E) attention and perception. The results showed the importance of several modular aspects that affect Space awareness in humans. Preliminary results are discussed with regard to current neuroscience, factor analysis, and possible implications for the understanding of contact with extraterrestrial intelligence. The roles of education, new search strategies, and possible contact scenarios are also discussed.  相似文献   

15.
The rationale for the use of interstellar artifacts by intelligent life in the universe is described. The advantages of using interstellar probes as a means of exploration and communication are presented and shown to be significant enough to counter the time, energy, and technology arguments generally raised against contact via extraterrestrial artifacts. Four classes of artifacts are defined: Those seeking contact, those seeking to avoid contact, those intended to provide a passive technological threshold for detection, and those for which detection is irrelevant. The Search for Extraterrestrial Artifacts (SETA) is based on the latter two classes. Under the assumption that an extraterrestrial probe will be interested in life in our solar system, a near-Earth search space is defined. This search space is accessible to us now with ground and satellite observing facilities. The current observational status of SETA is reviewed and contrasted with the achievable detection limits for the different parts of the search space.  相似文献   

16.
卫星与深空动态场景的实时仿真对于航空航天、军事国防等领域有着重要意义。现提出了一个深空动态场景的绘制方法,该方法综合了计算机图形学和天文学的知识,建立了基于天文学星表的深空场景模型,计算出卫星及各星体的运行轨迹,实现了卫星目标和深空场景的真实感合成,并采用一系列加速绘制技术,最终实现了深宅动态场景的实时生成和交互式虚拟漫游。  相似文献   

17.
Lichens survive in space: results from the 2005 LICHENS experiment   总被引:5,自引:0,他引:5  
This experiment was aimed at establishing, for the first time, the survival capability of lichens exposed to space conditions. In particular, the damaging effect of various wavelengths of extraterrestrial solar UV radiation was studied. The lichens used were the bipolar species Rhizocarpon geographicum and Xanthoria elegans, which were collected above 2000 m in the mountains of central Spain and as endolithic communities inhabiting granites in the Antarctic Dry Valleys. Lichens were exposed to space in the BIOPAN-5 facility of the European Space Agency; BIOPAN-5 is located on the outer shell of the Earth-orbiting FOTON-M2 Russian satellite. The lichen samples were launched from Baikonur by a Soyuz rocket on May 31, 2005, and were returned to Earth after 16 days in space, at which time they were tested for survival. Chlorophyll fluorescence was used for the measurement of photosynthetic parameters. Scanning electron microscopy in back-scattered mode, low temperature scanning electron microscopy, and transmission electron microscopy were used to study the organization and composition of both symbionts. Confocal laser scanning microscopy, in combination with the use of specific fluorescent probes, allowed for the assessment of the physiological state of the cells. All exposed lichens, regardless of the optical filters used, showed nearly the same photosynthetic activity after the flight as measured before the flight. Likewise, the multimicroscopy approach revealed no detectable ultrastructural changes in most of the algal and fungal cells of the lichen thalli, though a greater proportion of cells in the flight samples had compromised membranes, as revealed by the LIVE/DEAD BacLight Bacterial Viability Kit. These findings indicate that most lichenized fungal and algal cells can survive in space after full exposure to massive UV and cosmic radiation, conditions proven to be lethal to bacteria and other microorganisms. The lichen upper cortex seems to provide adequate protection against solar radiation. Moreover, after extreme dehydration induced by high vacuum, the lichens proved to be able to recover, in full, their metabolic activity within 24 hours.  相似文献   

18.
Columba Peoples   《Space Policy》2010,26(4):205-208
Discussions of space security tend to recurrently return to the vexed issue of the ‘militarization’ and ‘weaponization’ of outer space. Debate over whether or not a sustainable definition can be maintained between these two concepts has been a feature of both academic and policy discourses, and has been particularly contentious with regard to new proposals for arms control in outer space. Yet, this paper argues, the militarization/weaponization debate fails to capture to vagaries of contemporary space policy with regard to understandings of ‘security’, and is in this sense an insufficient way of approaching the subject of space security in the first instance. Instead it is now more accurate to say that outer space is becoming ever more ‘securitized’: that is, access to space is now commonly framed as crucial to the military, economic and environmental security of leading states and international organizations.  相似文献   

19.
The Lithopanspermia space experiment was launched in 2007 with the European Biopan facility for a 10-day spaceflight on board a Russian Foton retrievable satellite. Lithopanspermia included for the first time the vagrant lichen species Aspicilia fruticulosa from Guadalajara steppic highlands (Central Spain), as well as other lichen species. During spaceflight, the samples were exposed to selected space conditions, that is, the space vacuum, cosmic radiation, and different spectral ranges of solar radiation (λ?≥?110, ≥200, ≥290, or ≥400?nm, respectively). After retrieval, the algal and fungal metabolic integrity of the samples were evaluated in terms of chlorophyll a fluorescence, ultrastructure, and CO(2) exchange rates. Whereas the space vacuum and cosmic radiation did not impair the metabolic activity of the lichens, solar electromagnetic radiation, especially in the wavelength range between 100 and 200?nm, caused reduced chlorophyll a yield fluorescence; however, there was a complete recovery after 72?h of reactivation. All samples showed positive rates of net photosynthesis and dark respiration in the gas exchange experiment. Although the ultrastructure of all flight samples showed some probable stress-induced changes (such as the presence of electron-dense bodies in cytoplasmic vacuoles and between the chloroplast thylakoids in photobiont cells as well as in cytoplasmic vacuoles of the mycobiont cells), we concluded that A. fruticulosa was capable of repairing all space-induced damage. Due to size limitations within the Lithopanspermia hardware, the possibility for replication on the sun-exposed samples was limited, and these first results on the resistance of the lichen symbiosis A. fruticulosa to space conditions and, in particular, on the spectral effectiveness of solar extraterrestrial radiation must be considered preliminary. Further testing in space and under space-simulated conditions will be required. Results of this study indicate that the quest to discern the limits of lichen symbiosis resistance to extreme environmental conditions remains open.  相似文献   

20.
With the commemoration in October 2007 of the Sputnik launch, space exploration celebrated its 50th anniversary. Despite impressive technological and scientific achievements the fascination for space has weakened during the last decades. One contributing factor has been the gradual disappearance of mankind's hope of discovering extraterrestrial life within its close neighbourhood. In striking contrast and since the middle of the 20th century, a non-negligible proportion of the population have already concluded that intelligent beings from other worlds do exist and visit Earth through space vehicles popularly called Unidentified Flying Objects (UFOs). In light of the continuous public interest for the UFO enigma symbolized by the recent widely diffused media announcements on the release of French and English governmental files; and considering the approach of broadening the strategies of the “Active SETI” approach and the existence of a rich multi-disciplinary UFO documentation of potential interest for SETI; this paper describes some past scientific attempts to demonstrate the physical reality of the phenomena and potentially the presence on Earth of probes of extraterrestrial origin. Details of the different instrumented field studies deployed by scientists and organizations during the period 1950–1990 in the USA, Canada and Europe are provided. In conclusion it will be argued that while continuing the current radio/optical SETI searches, there is the necessity to maintain sustaining attention to the topic of anomalous aerospace phenomena and to develop new rigorous research approaches.  相似文献   

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