Planetary Protection in Future Solar System Exploration. Planetary Protection in Future Solar System Exploration

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1 E S P I 64 PERSPECTIVES Planetary Protection in Future Solar System Exploration Arne LAHCEN Project Manager at the European Space Policy Institute This Perspective analyses the importance of planetary protection in the future exploration of the Solar System. A major obstacle in this respect seems to be the contested scope of planetary protection. Although the more specific issue of planetary contamination has been addressed by the United Nations and various national space agencies, none of them have developed a holistic and all-embracing concept of planetary protection. As a consequence, the increasing number of planetary exploration probes, the prospect of a sample return mission - and maybe even manned missions to Mars in the long run - might have side-effects that limit future options, resulting in catastrophic events, or putting humankind in a position that might be regretted in the future, given the changing relationship between the environment and ourselves. Although the exploration of Mars is most relevant in this respect, the issues addressed in this Perspective might be relevant in establishing a sustainable relationship with the Solar System as a whole. 1. Introduction Literally, planetary protection (PP) could be understood as the combination of all practices and actions that help protect one or more celestial bodies. In this wide interpretation, space utilisation has been an enabling asset in protecting the Earth and its inhabitants. Satellites have given us the opportunity to gather a diverse set of information, which in turn helps us address issues of land use, climate change, atmospheric and oceanic monitoring, etc. Most of the time, however, that is not the presumed substance of the concept planetary protection. Initially, the concept was postulated to prevent, or at least minimise, the impacts that can arise in the interplanetary exploration of celestial bodies by means of probes, robots or human exploration. A major matter of concern in this respect is planetary contamination. According to NASA, planetary protection is the term given to the practice of protecting solar system bodies such as planets, moons, comets, and asteroids from contamination by Earth life, and protecting Earth from possible life forms that may be returned from other solar system bodies 1. This definition clearly exposes the two major motivations for planetary protection. The first one aims at protecting science as the unbiased implementation of exobiological experiments must be ensured in order to avoid false conclusions. In the context of forward contamination this could lead to false positives (e.g. the discovery of traces of life on an extraterrestrial (ET) sample, while it is not indigenous), whereas false negatives are more likely to occur in the event of a planet-wide contamination by terrestrial life that would destroy existing extraterrestrial life. The second argument relates to safety. Often administered in the context of backward contamination, it states Earth s biosphere and the Moon must be protected against possible contamination by extraterrestrial forms of life, which could be embedded in return samples or carried by return probes or crews. 2 For backward 1 Conley, C., Planetary Protection: About Planetary Protection, NASA, 2010, 2 Goh, G.M. and Kazeminejad, B., Mars Through the Looking Glass: an Interdisciplinary Analysis of Forward and Backward Contamination Space Policy 20 (2004): ESPI Perspectives No. 64, December

2 contamination, the potential effects that are of concern about biohazards can be divided into three broad categories: (1) large-scale negative pathogenic effects in humans; (2) destructive impacts on Earth s ecological systems or environments; and (3) toxic and other effects attributable to microbes, their cellular structures, or extracellular products. 3 Various measures in terms of legislation and engineering have been developed to ensure a proper implementation and execution of planetary contamination practices. 2. The Focus on Planetary Contamination The idea of planetary protection already emerged during the formation of the space program in the United States. The International Astronautical Federation (IAF) first took a look at the problem in 1956, a year before Sputnik. Later, during the 1960s, the International Council of Scientific Unions established the Committee on Space Research (COSPAR). Despite its position as a consultative body of the United Nations only, this multidisciplinary committee has been able to determine the standards upon which national practices has been based for over the past 40 years. At the same time, the UN had created the Committee on the Peaceful Uses of Outer Space (UNCOPUOS). This committee has played a vital role in the development of space law as a respected field of international law, and has eventually led to a first legal basis for planetary protection. The first reference to the concept was included in the Declaration of Legal Principles Governing the Activities of States in the Exploration and Use of Outer Space. This UN resolution, however, did not contain any specific mention of biological contamination. COSPAR in the meantime adopted resolution 26, which provided the first international standards for planetary quarantine. The crowning achievement in terms of planetary protection legislation was the Treaty on Principles Governing the Activities of States in the Exploration and Use of Outer Space, including the Moon and Other Celestial Bodies, also referred to as the Outer Space Treaty (OST). Adopted by the UNCOPUOS in 1963, article IX of the OST defines that states shall pursue studies of outer space, including the moon and other celestial bodies, and conduct exploration of them so as to avoid their harmful contamination and also adverse changes in the environment of the Earth resulting from the introduction of extraterrestrial 3 U.S. National Research Council, Assessment of Planetary Protection Requirements for Mars Sample Return Missions, Washington D.C.: The National Academies Press, matter and, where necessary, shall adopt appropriate measures for this purpose. 4 COSPAR, responsible for the compliance with the PP provisions of the OST, has elaborated working methods for determining the bioburden 5 threshold on spacecraft and their components. As a result of new knowledge about the habitability of other celestial bodies and the capability of terrestrial microorganisms to survive in extreme environments, COSPAR s methodology has changed over time. Between 1964 and the mid- 1980s, a probabilistic approach was followed. It implied that space faring nationals had to conduct their unmanned exploration in such a way that the total probability of contamination during a specified quarantine period did not exceed In 1984, this quantitative policy was replaced by an entirely new and categorical approach, in which the requirements for bioburden reduction were dependant upon the target body and the type of mission. To this effect, expertise and various practices have been developed in-house by the different space agencies engaged in solar system exploration programmes. The bioburden assessment throughout spacecraft assembly, test and launch operations is based upon cleanroom cleanliness. Active bioburden reduction is mainly achieved by dry-heat sterilisation and physical cleaning methods by means of alcohol swaps. The latest developments include alternative sterilisation methods such as gas plasma treatment and UV irradiation. Note that abovementioned legislation and practices are only concerned with the issue of planetary contamination. A genuine planetary protection conceptualisation, however, is wider and requires a holistic, overarching perspective. 3. Towards an Integrated PP Approach? One could, for example, argue that we need to extend the interpretation of planetary protection beyond the instrumental protection of scientific resources as expressed in the planetary contamination policy. 6 In this view, the objective of planetary protection is much wider than merely avoiding planetary contamination. From a more distant perspective, this discussion on planetary protection fits in a wider tradition of environmental ethics. Different motivations in support of this 4 United Nations, 1966: Res. No. 2222, art. IX 5 Bioburden is the level of microbial contaminion, measured as the total number of microbes or by considering the microbial density. 6 Cockell, S.C. et al., Effects of a Simulated Martian UV Flux on the Cyanobacterium, Chroococcidiopsis sp Astrobiology 5.2 (2005): ESPI Perspectives No. 64, December

3 notion have been developed; basically they can be grouped into four categories of arguments: 7 1. The necessity argument implies that we need unaltered wilderness areas to create a complete and healthy concept of culture and civilisation. Without them, we are more philosophically barbaric. Some scholars argue that in some way wilderness areas, such as the concept of planetary reserves represent intelligence, since the label wilderness is a product of an animal that can think about the consequences of its actions on an environment and can work to mitigate them. 2. The unknown and indirect benefits argument: currently, we don t know what the unexplored might be able to tell us. If we keep representative regions intact or off-limits until we really do understand them, we might discover things that are of benefit to us at some future time. This argument applies to the possibility of life, but is in fact much wider. It could be argued that other celestial bodies may offer us entirely novel cultural and aesthetic experiences that may change the way we think about the natural world. 3. The future generations argument argues that even if we do not use a planetary resource ourselves, we should protect it for future generations. The conservation of unaltered surface areas expresses respect for the options and choices of future human beings and allows them the opportunity to make decisions about how they would use (or not use) other celestial bodies. This notion is quite controversial among some ethicists on grounds of logic, nevertheless most would probably agree that maximising the choices available for future generations is a responsible environmental position to take. 4. The intrinsic value argument is quite controversial among scholars in terms of applicability and is even questioned on metaphysical grounds since the dawn of Western Philosophy in Ancient Greece. Basically it states that some things can have a value in itself, or for its own sake. 8 In this case it implies a planetary resource has its own value and should be left alone in appreciation of this value. This expresses the idea that value in an object exists independently of human valuation. Not too many ethicists adopt this position, but nevertheless it is an important point of discussion in ethics, particularly when applied to extraterrestrial bodies, most of which are presumed lifeless. This argument could be objected to by claiming that we, as humans, have the right to alter environments outside our own habitat simply because we have the means to do so. However, if we do think abiotic objects have some type of intrinsic value, then from this emerges a need to respect the surface and subsurfaces of places such as the Moon, Mars and other celestial bodies in our solar system. The last argument is closely related with the relatively recent call for the development of a Cosmocentric ethic. Such logic has been defined as characterised by four features: it should (1) place the universe at the centre, or establish the universe as the priority in a value system, (2) appeal to something characteristic of the universe which might then (3) provide justification of value, presumably intrinsic value and (4) allow for 7 Cockell, C. and Horneck, G., Planetary Parks Formulating a Wilderness Policy for Planetary Bodies. Space Policy 22 (2006): Zimmerman, M.J., Intrinsic versus Extrinsic Value, The Stanford Encyclopedia of Philosophy (Winter 2010 Edition), Edward N. Zalta ed., reasonable objective measurement of value. This might also be helpful in dealing with value based questions involving issues such as interaction with indigenous primitive extraterrestrial life forms Future Challenges Giving a more profound substance to the concept of PP by means of aforementioned arguments might, however, prove very difficult and timeconsuming. A more pragmatic approach therefore might be to start from the concrete or conceivable challenges that await us. In this respect, we can distinguish three stages of further development in solar system exploration. The first group consists of missions with a mission design relatively similar to previous missions; all of them are situated in the near future (before 2020 horizon). The second category includes sample return missions, as they entail the additional risk of backward contamination. Finally, a human mission, to Mars for example, is in so many ways more complex and challenging than previous categories that it deserves special attention. 4.1 Near Future As many robotic missions to celestial bodies are concerned with the quest for extraterrestrial life, we should anticipate eventual discoveries. While formal principles have been adopted for the eventuality of detecting intelligent life in our galaxy, the so-called SETI Principles, no such guidelines exist for the discovery of non-intelligent extraterrestrial life within the solar system. 10 As a result, current scientifically based PP policies for solar system exploration address how to undertake exploration, but do not provide clear guidance on what to do if and when non-intelligent life is detected. Ironically, the underlying ethical principles for microbial ET life are actually more complex and practice-oriented than for intelligent ET-life. The resulting, more future-oriented, ethical question relates to our behaviour towards a putative non-intelligent extraterrestrial ecosystem and its home planet. Of all ethical concerns in PP, this might be the one most unusual and far reaching. It can be argued that mankind has a moral obligation to respect the integrity of extraterrestrial ecosystems, just as we should do on Earth. In this view, ET-ecosystems should continue to function essentially the same as they did before their discovery. However, one might argue that the motivation for this noble principle tends to introduce a dual standard, as we do not always apply this rule on Earth, not for all 9 Lupisella, M. and Logsdon, J., eds. Do we Need a Cosmocentric Ethic? College Park: University of Maryland, SETI Institute, Declaration of Principles Concerning Activities Following the Detection of Extraterrestrial Intelligence. Acta Astronautica 21.2 (1990): ESPI Perspectives No. 64, December

4 humans, let alone all other organisms. The scientist and influential author Carl Sagan suggested that if there is life on Mars, we should do nothing with Mars, leaving the planet to the Martians, even if they are only microbes. 11 Others have suggested a more pragmatic approach, saying that we must explore the Solar System in a way that keeps our options open with respect to future life. Some even go as far as saying that we have no special obligation towards non-intelligent life, especially if the consequences substantially or unduly interfere with human interests of science and exploration. 12 A first step in terms of near-future PP is the development of a proper protocol and possibly the distinction between special and non-special regions on Mars and other moons and planets. In view of the process of internationalisation in space exploration, it might be recommendable to approach this as an international undertaking. In terms of planetary contamination, to date there is no standard certification process for approval of new bioload mitigation practices, whether for microbial reduction or assaying. It is essential for COSPAR to address this problem, especially with the prospect of the new bioburden assay and mitigation techniques available in the near future. 4.2 Mars Sample Return Future sample return missions, most likely a Mars Sample Return Mission (MSR), will occur in a dramatically different setting than those of earlier space exploration programmes. Three main drivers can be identified in this process: (1) as a generalisation, society has grown more risk averse over time, with the trend expected to continue in the foreseeable future, (2) these shifts in public attitudes about risks and technology have been matched by corresponding changes in legislation that have broadened the ability of citizens and groups to challenge public decisions, and (3) the higher potential risks involved in future Mars missions are more likely to give rise to more public scrutiny and societal opposition. Mars Sample Return missions could encounter intense scrutiny because of the public s concern about possible introduction of extraterrestrial matter or organisms onto Earth and the accompanying environmental, health and safety issues. This phenomenon is definitely not limited to space utilisation; there are plenty of examples of scientific and technical projects that were frustrated by public challenges and concerns. Common examples include nuclear power, biotechnology, food irradiation, and toxic waste incineration. Historically, NASA and ESA engineers and managers have been accustomed to reaching decisions through a highly technical, expert process with only minimal input from the public. However, decisions about PP will undoubtedly impose a heavy load of social concerns onto mission planning, shifting the locus of decision making into a more public and democratic realm. Moreover, this is reinforced by the fact that simultaneous controversies are often expressed on multiple levels. In the case of a sample return, there are typically three: 13 The ideological focus or public policy focus, often dominated by philosophical questions such as should we do it. These kinds of arguments mostly have an ethical or moral overtone. Traditionally, this category also includes arguments administered by people who are opposed to the general idea at the centre of discussion. Arguments to expand the focus of planetary protection beyond instrumental protection of scientific resources into other utilitarian and intrinsic value arguments belong in this category. The focus concentrating on formulation of appropriate technical policies and procedures, dominated by questions of how should we do it? and emphasising a practical approach to decision making (e.g., formulation of government regulations, devising acceptable permit review processes, developing effective controls, etc.). In the case of planetary protection, COSPAR and the national agencies are characterised by this paradigm. A local focus, dominated by questions of why do it here or now?. This focus is interwoven with the Not In My Back Yard (NIMBY) phenomenon often displayed in infrastructure projects. In this case it will occur in the site selection of Mars Sample Receiving Facilities on Earth. Nevertheless, the advent of technological decision making into the public arena and the related changing process of decision making about scientific and technological risks is not a problem per se. To minimise the chances of disruption to future missions, space agencies must, however first proactively analyse and develop information in a number of key areas related to planetary protection in terms of mission architecture, legal aspects, management, and research & development. Based on this information, risk assessment studies have to be performed and the results hereof communicated properly towards the public. Potentially, an all-embracing approach could also address differences in ideological focus by adapting existing techniques and methods that have been developed in environmental sociology, such as Social Impact Assessment (SIA) for example. This assessment technique tries to help 11 Sagan, C., ed. Cosmos. New York: Ballantine Books, Zubrin, R., ed. The Case for Mars. New York: Free Press, Race, M.S. Societal Issues as Mars Mission Impediments: Planetary Protection and Contamination Concerns Advances In Space Research, 15.3 (1995): ESPI Perspectives No. 64, December

5 individuals and communities, as well as government and private-sector organisations, understand and better anticipate the possible social consequences for human populations and communities of planned and unplanned social change resulting from proposed policies, plans, programmes and projects. All serious planning for MSR is founded on the premise that the scope, complexity, and cost of such a mission are beyond the likely resources of any individual space agency. The size of the Mars exploration community is expanding and at the same time, broadening of the scope of mission activities and international cooperation by both traditional and new space powers is taking place. In spite of the positive aspects of this tendency, this factor is also likely to complicate the policies and protocols relating to sample containment and biohazard evaluation. Although no major issues have arisen to date, the international interest in MSR raises the possibility that differences in national policies and legal frameworks of concerned parties might complicate issues relating to sample quarantine and biohazard certification. To minimise these impeding factors, detailed protocols for sample containment, handling, and testing, including criteria for release from a sample-receiving facility, should be clearly articulated in advance of a Mars sample return. Also, these protocols should be reviewed periodically as part of the ongoing Science Research Facility oversight process that will incorporate new laboratory findings and advances in analytical methods and containment technologies. The international partners involved with the implementation of a MSR mission should be a party to all necessary consultations, deliberations, and reviews Manned Missions On Earth it is becoming ever clearer that our existing moral principles, when it comes to life and the environment, are far from ideal or sustainable. Consequently, we might not want to undertake further space exploration based on the same values we employ on Earth. One important benefit of space exploration could, therefore, be philosophical in nature: developing a sustainable model of exploration and exploitation of environments. In this sense, ethics can be regarded as the next frontier of space exploration. 15 While this opportunity is hopeful in developing a long-term perspective, most ethical and societal aspects that arise in a human space 14 U.S. National Research Council, Assessment of Planetary Protection Requirements for Mars Sample Return Missions. Washington D.C.: The National Academies Press, Reiman, S. On Sustainable Exploration of Space and Extraterrestrial Life. Journal of Cosmology 12 (2010): exploration mission will confront us with more practical challenges that need addressing first. The need for sufficient quantities of oxygen, water, and fuel resources to support a crew on the surface of Mars presents a critical logistical issue of whether to transport such resources from Earth or manufacture them on Mars. In this regard, the opportunity of In Situ Resource Utilisation (ISRU) technologies have the potential to significantly reduce launch mass delivered from Earth by producing propellants and consumables for life support from indigenous Mars resources. 16 Besides the technical difficulties arising in this respect, we would need to consider how and why we would use these extraterrestrial resources and how we deal with the waste that will be produced as a side-effect of the treatment process. Given that forward contamination is a significantly greater risk with human missions than in robotic missions, it could be argued some regions should be avoided or let alone. This option is in line with the idea of planetary parks on Mars, analogous to wilderness reserves on Earth. If these regions are of special interest for the science goals determined, it might be argued to land outside these zones, and then go there by means of a Mars surface vehicle or by other means of astronaut mobility. Another matter demanding profound reflection is the position of the astronauts in the prevention of planetary contamination. Living humans invariably carry associated microbial population that are necessary for our survival, and treating humans by the same methods used to reduce the bioburden of spacecraft and robotic systems would kill them. This raises some interrelated questions on the status of astronauts as both contaminated victims and vectors of contamination. For instance, it is not unreasonable to wonder whether the slightest sign of fatigue or faintest weakness exhibited by returning astronauts might be interpreted as a possible symptom of extraterrestrial contamination. How will they then be viewed and treated? Typically, when humans themselves become contaminating agents there are two types of responses: an active one by means of antibiotics or vaccines and passive by quarantine precautions. Even if we would know what caused the contamination, neither of those responses would be easy to apply in space or upon return. Additional concerns arise if the contaminant and its causes are unknown. Could we really envisage permanent quarantine for returning astronauts who have embarked on a mission as envoys of mankind? 16 Smith, J.H. ed. In-Situ Resource Utilization for the Human Exploration of Mars: a Bayesian Approach to Valuation of Precursor Missions. Pasadena: JPL, ESPI Perspectives No. 64, December

6 Finally, in legal terms, it might be recommendable to develop some sort of Planetary Protection Code of Conduct for Crew of a Manned Mars Mission for the duration of stay on the red planet, inspired by the nature of the existing Code of Conduct for the International Space Station Crew. Such an international code, subscribed at least by all participating states, could set forth the scope, applicability and crew responsibilities in planetary protection practices and behaviour on the planet. It should also address the authority of the crew member given primary responsibility for the implementation of planetary protection provisions. 5. Conclusion The precautious approach in Solar System exploration so far has enabled us to safeguard scientific interests in the research on cosmic habitability and the quest for extraterrestrial life forms. The approach is expressed by international legislation under the UN framework and the responsibilities of the Committee on Space Research. Practically, space agencies have developed the capabilities necessary to assess and keep the bioburden on spacecrafts limited to what would appear to be acceptable levels. However, the principal focus on planetary contamination has obstructed the conceptualisation of an all-embracing and genuine planetary protection vision and policy. The practice of environmental ethics offers some interesting perspectives in this respect, practical implementation, however, proves difficult. The most pragmatic solution presented takes the concrete or conceivable challenges that await us in the future as a starting point. This results in an analysis of the challenges related to near future missions, sample return missions and human missions to other celestial bodies. In itself, none of these challenges are fundamentally different from other challenges we are faced with on Earth. Neither is the issue of the level of risk acceptance or risk reduction by entities on different levels like individual researchers, explorers, and institutions. Nonetheless, it would be sensible to keep asking ourselves what price we are willing to pay for endeavours like space exploration in terms of resources, environmental responsibilities and human safety. In the long run, this link between space utilisation and ethics might have benefits in other societal fields as well. ESPI Perspectives No. 64, December

7 Mission Statement of ESPI The European Space Policy Institute (ESPI) provides decision-makers with an informed view on midto long-term issues relevant to Europe s space activities. In this context, ESPI acts as an independent platform for developing positions and strategies. Available for download from the ESPI website Short title: ESPI Perspectives 64 Published in December 2012 Editor and publisher: European Space Policy Institute, ESPI Schwarzenbergplatz 6 A-1030 Vienna Austria Tel: / Fax: office@espi.or.at Rights reserved No part of this report may be reproduced or transmitted in any form or for any purpose without permission from ESPI. Citations and extracts to be published by other means are subject to mentioning Source: ESPI Perspectives 64, December All rights reserved and sample transmission to ESPI before publishing. ESPI Perspectives are short and concise thought or position papers prepared by ESPI staff as well as external researchers. Any opinion expressed in this ESPI Perspective belongs to its author and not to ESPI. The author takes full responsibility for the information presented herein. 7