Space exploration and human survival

I am sympathetic to the view that, given the likelihood of massive natural disasters, such as collisions between the Earth and large asteroids, we should engage in large-scale space exploration and colonization so as to hedge our bets against extinction. I will consider several criticisms of this view. For example, some philosophers may raise objections against the notion of long-term human survival as a value. How can we have obligations towards beings who have not even been conceived yet and thus cannot be properly said to have rights? On a different note, Wendell Berry argues that the abundance of resources in space will produce bad character, for good character requires the discipline of finitude. Others challenge the connection between space exploration and survival, for they fear that by entertaining the promise of new Earths in the heavens we are more likely to neglect our planet, thus leading to our downfall. Presumably, we should instead increase our efforts to restore and preserve the balance of nature. I will advance a variety of replies. For example, we do decide for posterity to a great extent. We may plant the trees from which “our” descendants will receive nourishment and shade, or we may destroy what could have given them a fighting chance against drought and famine. We have an obligation not to plant a bomb that will go off two years from now in a hospital nursery, and another to ensure that the buildup of chemicals in the hospital water tank will not reach critical mass and kill most of the newborns in ten years. The “balance of nature” involved in another objection is a myth that cannot be justified by natural history, whether astronomical or biological. Moreover, the inevitable changes in the environment, independent of asteroid impacts, will make the Earth uninhabitable in a few hundreds of millions and years. In addition, in order to act wisely we need an understanding of the Earth as a planet, and this requires the exploration of space.     

无控航天器与空间碎片再入的工程预测方法研究现状

无控航天器、火箭末级以及空间碎片再入地球大气层后可能未烧尽,残存的小碎片高速撞击地面,对人类安全和生态系统构成极大威胁。提前预测其再入轨迹并采取预防措施能够有效降低地面风险。文章对无控航天器和空间碎片再入工程预测模型,包括航天器模型、动力学模型、气动热模型和烧蚀解体模型的研究现状进行跟踪与总结,也介绍了国内外有公开资料的工程应用软件,并讨论若干关键问题和进一步研究方向。     

How shall we live in space? Culture, law and ethics in spacefaring society

The US civilian space program is focused on planning for a new round of human missions beyond Earth orbit, to realize a ‘vision’ for exploration articulated by President George W. Bush. It is important to examine this ‘vision’ in the broader context of the global enterprise of 21st century space exploration. How will extending a human presence into the Solar System affect terrestrial society and culture? What legal, ethical and other value systems should govern human activities in space? This paper will describe the current environment for space policy making and possible frameworks for future space law, ethics and culture. It also proposes establishment of a World Space Conference to aid deliberations on the above.     

The mitigation, management, and survivability of asteroid/comet impact with Earth

The chances that Earth will collide with a significant near earth object (NEO) within the next century are very small, but such a collision is possible, would be catastrophic, and could happen at any time. Much discussion has been devoted to methods of diverting these objects away from Earth through the use of space technology. However, if these efforts are unsuccessful, we would need to implement effective strategies to survive the event, no matter how cataclysmic. To date, disaster management for various impact scenarios has not been addressed (except in novels and Hollywood films). An impact disaster may be many orders of magnitude greater than any disaster the human species has ever experienced. Initially, technology and experience gained in other large-scale disasters will most likely form the foundation of how these impact events will be managed and classified. Given the size and energy of the projectile, the estimated area of damage, and whether impact effects might be localized or global in nature, we can begin to build basic disaster response scenarios, anticipate public health concerns, and formulate questions in need of answers. Questions we must deal with include: what will be required technologically, sociologically, and medically to survive? What types of evacuation plans and warning systems might be required? Capabilities in need of further investigation include: technological protection strategies related to ‘impact winter’, expanded chemical hazard control methodologies, food storage and production, roles of national governments, and international cooperation. Whatever the magnitude and severity of the event, we must reflect on what we know, what capabilities we can apply, develop or adapt, and seriously investigate what might be done to manage it and survive.     

Earth observation from space – The issue of environmental sustainability

Remote sensing scientists work under assumptions that should not be taken for granted and should, therefore, be challenged. These assumptions include the following:1. Space, especially Low Earth Orbit (LEO), will always be available to governmental and commercial space entities that launch Earth remote sensing missions.2. Space launches are benign with respect to environmental impacts.3. Minimization of Type 1 error, which provides increased confidence in the experimental outcome, is the best way to assess the significance of environmental change.4. Large-area remote sensing investigations, i.e. national, continental, global studies, are best done from space.5. National space missions should trump international, cooperative space missions to ensure national control and distribution of the data products.At best, all of these points are arguable, and in some cases, they're wrong. Development of observational space systems that are compatible with sustainability principles should be a primary concern when Earth remote sensing space systems are envisioned, designed, and launched. The discussion is based on the hypothesis that reducing the environmental impacts of the data acquisition step, which is at the very beginning of the information stream leading to decision and action, will enhance coherence in the information stream and strengthen the capacity of measurement processes to meet their stated functional goal, i.e. sustainable management of Earth resources. We suggest that unconventional points of view should be adopted and when appropriate, remedial measures considered that could help to reduce the environmental footprint of space remote sensing and of Earth observation and monitoring systems in general. This article discusses these five assumptions in the context of sustainable management of Earth's resources. Taking each assumption in turn, we find the following:(1) Space debris may limit access to Low Earth Orbit over the next decades.(2) Relatively speaking, given that they're rare event, space launches may be benign, but study is merited on upper stratospheric and exospheric layers given the chemical activity associated with rocket combustion by-products.(3) Minimization of Type II error should be considered in situations where minimization of Type I error greatly hampers or precludes our ability to correct the environmental condition being studied.(4) In certain situations, airborne collects may be less expensive and more environmentally benign, and comparative studies should be done to determine which path is wisest.(5) International cooperation and data sharing will reduce instrument and launch costs and mission redundancy. Given fiscal concerns of most of the major space agencies – e.g. NASA, ESA, CNES – it seems prudent to combine resources.     

Space ethics and protection of the space environment

The construction of the International Space Station in low Earth orbit and the formulation of plans to search for life on Mars indicate that mankind is intent on making the space environment part of its domain. Publicity surrounding space tourism, in-space ‘burials’ and the sale of lunar ‘real estate’ suggests that, some time in the 21st century, the space environment will become an extension of our current terrestrial business and domestic environment. This prompts the question of our collective attitude towards the space environment and the degree to which we should regulate its use and protect it for future generations. This article offers a pragmatic view of an ethical code for space exploration and development, as far as it relates to the protection of the space environment.     

The impact of culture on human and space development--new millennial challenge

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.     

Testing interplanetary transfer of bacteria between Earth and Mars as a result of natural impact phenomena and human spaceflight activities

Interplanetary transport of microbes between Earth and Mars can be envisioned to occur either naturally as a consequence of impacts (lithopanspermia) or as a result of human and robotic spaceflight. In either case, the considerations for modeling successful transfer of microbial life are similar. The probability of microbes surviving either natural or human-mediated transfer is a function of: the initial population size and composition (i.e., the bioload); survival of launch, transit through space, entry and deposition; and ability to survive and proliferate on the recipient planet. Modeling this process for testing lithopanspermia and for mitigation of forward and back contamination for planetary protection purposes calls for accurate simulation of all aspects of transfer.     

Space and the fate of humanity

Current growth and consumption rates on Earth cannot be sustained into the future. Space technology is already a vital tool in the management of the planet and we should look at it to mitigate some of the problems we face. However, this should not include colonization of interstellar space. Rather we should focus on using solar energy from space and on mining asteroids, both of which would be feasible if the Moon was developed as a space base and power station. The most difficult and expensive part of getting into space is escaping Earth's gravity - something that could be avoided once a presence was established on the Moon. A lunar base would also provide the obvious site from which to reach GEO, travel to Mars or back to Earth and, ultimately, to explore the further reaches of the Solar System.     

Superlight rotating reflectors in space

There is a general possibility of creation in space of large controlled mirror reflectors for solar and electromagnetic radiation with specific mass order of 1 g m^?2 or less. Such reflectors may be used in space energetics for concentration of solar energy for its further conversion into microwave beam and transmission to the Earth. They can also be used to illuminate the Earth surface in a dark period with reflected sunlight, to control the weather, for research work and some other purposes. Such reflector is a good solar sail. The control of its orientation and position in space is performed using solar energy and light pressure without spending fuel delivered from the Earth. Its form is maintained by centrifugal forces and light pressure. The film strength permits concentrators with radii of several kilometres and nearly flat reflectors for lighting applications with radii of hundreds of metres. Large series of identical reflectors can be built in space using superthin film tape at assembly station. For a year more than a hundred reflectors with a diameter of 600 m can be assembled at such a station. The assembly station can be placed at the height of 1000 km. The reflectors transfer to synchronous or other orbit is performed using their sail-likeness. For realization of such reflectors one should solve a very difficult problem of superthin film mass production as well as assembly technology problems. Careful study and experimental checks of their lifetime should be also made.     

Language protocols in international human spaceflight: Time for a common tongue?

As international partnerships increasingly look to be the way forward for sustainable human space exploration, the need to think about language protocols becomes more pressing. Using the historical examples of three international human spaceflight missions, this viewpoint shows how each language protocol was dictated by political realities and how often difficulties arose during implementation as a result. It is argued that, in order to optimize operational environments in future human space exploration, the international space community should adopt a standardized, single-language protocol, similar to commercial aviation. While English may appear to be the most obvious candidate, other languages, particularly Russian and perhaps even Chinese, may also be worth considering.     

Property rights and the duty to extend human life

This article examines what the author calls the ‘argument from duty’, i.e. the argument that we should recognize private property rights in space because doing so will help us to act upon our duty to ensure the future survival of humanity. More strongly, the motivational impact of recognizing such rights may be required if we are to act upon this duty in an effective manner. The article argues that the duty in question is important but not overriding and that there are other duties with which it may happen to conflict. More specifically, the practical requirements of human resettlement may conflict with our duty to pursue a more just and environmentally sensitive way of living here on Earth. If this is correct, only a significantly weakened argument from duty may be made. The article also strengthens the case for thinking about our duties in the light of other ethical considerations.     

On the contribution of space medicine in the public health care

With the beginning of space era, a new branch of medicine has arisen and has been developing along with human exploration of outer space. And even though space medicine mainly faces the same problems as traditional medicine--cosmonauts health care and their high efficiency--this branch, has its own features, associated with the unusual factors of space flight, of which weightlessness is the major one. During the development of manned cosmonautics (duration of a human stay in space has reached already 438 days), methods of cosmonauts medical support and monitoring of their condition have been developed, knowledge of human possibilities and methods of process of organism adaptation to various and frequently severe conditions of external environment have increased. All this led to the fact that nowadays space medicine can become useful for improvement of human health care not only in space but also on the Earth. Moreover, the problem of implementation of cosmonautics achievements, and in particular of space medicine, in practice of public health care presents one of the most important issues concerning human health care. It is also connected with public opinion which is more and more concerned about the efficiency of significant expenses on space activities, especially lately. People often are set by the questions: what has space given, what fruits has space research provided to mankind, which results of this research can be used on the Earth already today for improvement of their life, for discussion of many difficult earthly problems? In terms of using cosmonautics possibilities, its achievements for health care and treatment, it is possible to define a few branches, in which purposeful studies are carried out.     

Assessment on the feasibility of future shepherding of asteroid resources

Most plausible futures for space exploration and exploitation require a large mass in Earth orbit. Delivering this mass requires overcoming the Earth's natural gravity well, which imposes a distinct obstacle to any future space venture. An alternative solution is to search for more accessible resources elsewhere. In particular, this paper examines the possibility of future utilisation of near Earth asteroid resources. The accessibility of asteroid material can be estimated by analysing the volume of Keplerian orbital element space from which Earth can be reached under a certain energy threshold and then by mapping this analysis onto an existing statistical near Earth objects (NEO) model. Earth is reached through orbital transfers defined by a series of impulsive manoeuvres and computed using the patched-conic approximation. The NEO model allows an estimation of the probability of finding an object that could be transferred with a given Δv budget. For the first time, a resource map provides a realistic assessment of the mass of material resources in near Earth space as a function of energy investment. The results show that there is a considerable mass of resources that can be accessed and exploited at relatively low levels of energy. More importantly, asteroid resources can be accessed with an entire spectrum of levels of energy, unlike other more massive bodies such as the Earth or Moon, which require a minimum energy threshold implicit in their gravity well. With this resource map, the total change of velocity required to capture an asteroid, or transfer its resources to Earth, can be estimated as a function of object size. Thus, realistic examples of asteroid resource utilisation can be provided.     

Survival of plant seeds, their UV screens, and nptII DNA for 18 months outside the International Space Station

The plausibility that life was imported to Earth from elsewhere can be tested by subjecting life-forms to space travel. Ultraviolet light is the major liability in short-term exposures (Horneck et al., 2001 ), and plant seeds, tardigrades, and lichens-but not microorganisms and their spores-are candidates for long-term survival (Anikeeva et al., 1990 ; Sancho et al., 2007 ; J?nsson et al., 2008 ; de la Torre et al., 2010 ). In the present study, plant seeds germinated after 1.5 years of exposure to solar UV, solar and galactic cosmic radiation, temperature fluctuations, and space vacuum outside the International Space Station. Of the 2100 exposed wild-type Arabidopsis thaliana and Nicotiana tabacum (tobacco) seeds, 23% produced viable plants after return to Earth. Survival was lower in the Arabidopsis Wassilewskija ecotype and in mutants (tt4-8 and fah1-2) lacking UV screens. The highest survival occurred in tobacco (44%). Germination was delayed in seeds shielded from solar light, yet full survival was attained, which indicates that longer space travel would be possible for seeds embedded in an opaque matrix. We conclude that a naked, seed-like entity could have survived exposure to solar UV radiation during a hypothetical transfer from Mars to Earth. Chemical samples of seed flavonoid UV screens were degraded by UV, but their overall capacity to absorb UV was retained. Naked DNA encoding the nptII gene (kanamycin resistance) was also degraded by UV. A fragment, however, was detected by the polymerase chain reaction, and the gene survived in space when protected from UV. Even if seeds do not survive, components (e.g., their DNA) might survive transfer over cosmic distances.     

国外空间环境试验与探测技术现状与发展趋势

文章分析了与航天器飞行有关的4类空间环境的特点;介绍了国外空间环境试验技术的现状与发展概况。文章还重点分析了未来空间环境探测的发展趋势:加强了对空间环境动态变化的探测;将星座探测摆在重要地位;以地球轨道卫星为发展的主流;利用卫星加大对空间环境探测的力度;加强国际合作。国外空间环境探测的经验表明,我国应重视发展地球轨道探测卫星,尽快提高卫星有效载荷的水平。     

Is space an environment?

Expanding the human sphere of influence beyond Earth presents philosophical questions that also have important practical applications. Do we need to worry about the moral implications of our actions in the vastness of space? What kind of explorers will we be - and what kind of explorers should we be? The answers to these basic questions depend greatly on what moral status is assigned to space; how it is conceptualized. This article sets forth arguments both for and against considering space as an environment, that is, as a place deserving of ethical treatment in the same way that terrestrial environments are valued and respected in environmental ethics. It sketches some answers to how space exploration could meet high ethical standards and puts forward the notion of environmental ‘virtue ethics’.     

Scenarios which may lead to the rise of an asteroid-based technical civilisation

In a previous paper, the author described a hypothetical development path of technical civilisations which has the following stages: planet dwellers, asteroid dwellers, interstellar travellers, interstellar space dwellers. In this paper, several scenarios are described which may cause the rise of an asteroid-based technical civilisation. Before such a transition may take place, certain space technologies must be developed fully (now these exist only in very preliminary forms): closed-cycle biological life support systems, space manufacturing systems, electrical propulsion systems. After mastering these technologies, certain events may provide the necessary financial means and social impetus for the foundation of the first asteroid-based colonies. In the first scenario, a rich minority group becomes persecuted and they decide to leave the Earth. In the second scenario, a "cold war"-like situation exists and the leaders of the superpowers order the creation of asteroid-based colonies to show off their empires' technological (and financial) grandiosity. In the third scenario, the basic situation is similar to the second one, but in this case the asteroids are not just occupied by the colonists. With several decades of hard work, an asteroid can be turned into a kinetic energy weapon which can provide the same (or greater) threat as the nuclear arsenal of a present superpower. In the fourth scenario, some military asteroids are moved to Earth-centred orbits and utilised as "solar power satellites" (SPS). This would be a quite economical solution because a "military asteroid" already contains most of the important components of an SPS (large solar collector arrays, power distribution devices, orbit modifying rocket engine), one should add only a large microwave transmitter.     

The need for a United Nations space policy

The international community is entering an era of shared global utilities from space and is increasingly reliant on space systems and activities that support a myriad of applications and utilities on Earth. A growing number of states are seeking to develop or extend their space capabilities. At the same time, a variety of non-state actors are also extending their involvement in space activities. The United Nations is the principal inter-governmental forum to deal with various space issues of global importance. Moreover, the United Nations system itself has become increasingly reliant on space systems for its day-to-day operations. In order for the United Nations to play its necessary role in the space arena, it will need to be supported by a space policy. A United Nations space policy would provide over-arching guidance on space activities for UN stakeholders in the space arena; it would inform UN participation in space activities and would promote improved coordination and cooperative governance of outer space activities. A world without a common UN space policy will not be able to respond to the challenges of the rapidly evolving space arena in the 21st century.     

Magnetic trapping in orbit

A toroidal solenoid in orbit can represent a magnetic trap for bodies carrying dipole moment. We find the dependence of the trap dimensions on the electrical parameters and the orbit height. There is no trap if the solenoid radius exceeds a certain value. Various trap dimensions are calculated for a non-spinning space station in Earth or Sun orbit. The trap dimension is nearly independent of the solenoid orientation so that the solenoid may be fastened to the station rigidly. If the solenoid radius is in the range of some meters, the trap dimension is one order of magnitude greater for a distant Earth orbit and two orders of magnitude for an orbit around the Sun at distances of the order of one AU. The calculations are performed for a non-superconducting solenoid. The trap can be used for simplifying the docking on of maintenance vehicles or building modules, as safety mechanism for crewmembers working in outer space, and for the collection of paramagnetic or ferromagnetic dust stopped by mechanical means.