Advances in Space Research 38 (2006) 2225–2231 www.elsevier.com/locate/asr Public communication strategy for NASAÕs planetary protection program: Expanding the dialogue Linda Billings SETI Institute, 3654 Vacation Lane, Arlington, VA 22207, USA Received 2 September 2004; received in revised form 10 October 2005; accepted 12 October 2005 Abstract The US National Aeronautics and Space Administration (NASA) Planetary Protection Office, in the Science Mission Directorate, has a long-term initiative under way in communication research and planning. The possibility of extraterrestrial life and efforts to search for evidence of it is one of NASAÕs key missions and a subject of great interest to the public. Planetary protection plays a key role in the search for signs of life elsewhere, and NASAÕs Planetary Protection Office has long recognized the importance of communications in accomplishing its goals and objectives. With solar system exploration missions advancing into the era of sample return and with the science of astrobiology changing assumptions about the nature and boundaries of life, the NASA Planetary Protection Office is expanding its communication research efforts. For the past decade, communication research sponsored by the NASA planetary protection program has focused on reaching members of the science community and addressing legal and ethical concerns. In 2003, the program broadened its communication research efforts, initiating the development of a communication strategy based on an interactive model and intended to address the needs of a broad range of external audiences. The NASA Planetary Protection Office aims to ensure that its scientific, bureaucratic, and other constituencies are fully informed about planetary protection policies and procedures and that scientists and officials involved in planetary protection are prepared to communicate with a variety of public audiences about issues relating to planetary protection. This paper describes NASAÕs ongoing planetary protection communication research, including development of a communication strategy and a risk communication plan. Ó 2005 COSPAR. Published by Elsevier Ltd. All rights reserved. Keywords: Public understanding of science; Science communication; Outreach 1. Introduction Planetary protection is the term used in the international space community to describe policies and practices that are intended to prevent contamination of extraterrestrial environments by microbial Earth life (forward contamination) and contamination of EarthÕs environment by possible extraterrestrial microbial life (back contamination) in the course of solar system exploration (Rummel and Billings, 2004). NASA has a mandatory planetary protection policy in place (NASA Policy Directive (NPD) 8020.7F, Biological Contamination Control for Outbound and Inbound Planetary Spacecraft) that applies to all solar system explo- E-mail address: lbillings@seti.org ration missions. NASA also has established (NASA Procedural Requirements (NPR) 8020.12C, Planetary Protection Provisions for Robotic Extraterrestrial Missions) mandatory procedures for compliance with this policy. The international Committee on Space Research (COSPAR) has a similar policy in place (COSPAR Planetary Protection Policy, 20 October 2002), though compliance with it is voluntary. NASAÕs policy specifies that its Planetary Protection Office is responsible for preventing biological contamination in connection with solar system exploration. Beyond a concern for the possible effects of perennial heat sources (radioisotope thermoelectric generators, for instance) aboard spacecraft on the survivability of Earth life in extraterrestrial environments, the Planetary Protection Office is not chartered to ensure protection against nuclear contamination in connection with solar system exploration. It also 0273-1177/$30 Ó 2005 COSPAR. Published by Elsevier Ltd. All rights reserved. doi:10.1016/j.asr.2005.10.018 2226 L. Billings / Advances in Space Research 38 (2006) 2225–2231 is not chartered to ensure protection of Earth against asteroid impacts. The concept of planetary protection dates back to the beginning of the Space Age. The International Astronautical Federation and the United Nations Committee on the Peaceful Uses of Outer Space began consideration of planetary protection issues in 1956, and the US National Academy of Sciences first aired concerns about interplanetary contamination in 1957 (CETEX, 1958, 1959). Planetary protection involves many different disciplines and an array of national and international governmental and non-governmental organizations, and communication has always been an important element of the practice. With the pace of solar system exploration picking up (see National Research Council, New Frontiers, 2002), and with public concerns about biological contamination heightened due to concerns about global infectious disease spread and possible bioterrorism, communication is an increasingly important concern in the planetary protection community. 2. Planetary protection today As knowledge of the solar system advances, so does understanding of the need for planetary protection. For example, in fall 2003, as the Galileo spacecraft neared the end of its mission to Jupiter, NASA altered plans for the end of this mission to ensure that the Galileo spacecraft would burn up in JupiterÕs atmosphere and not accidentally crash on one of three especially interesting moons orbiting the planet (National Research Council, Quarantine, 2002; Rousseau, 2003). The reason for this change was that, in the course of its mission, Galileo had collected data indicating that liquid water oceans might exist beneath the frozen surface of the Jovian moons Callisto, Europa, and Ganymede (NRC, 1999). The possibility of liquid water in these extraterrestrial environments moved them toward the top of the list of promising astrobiological research targets in the solar system. When Galileo was launched in 1989, the Jovian system was not a promising target in the scientific search for extraterrestrial life. But the possible presence of liquid water changed that assessment. In a letter to NASAÕs Planetary Protection Officer dated 28 June, 2000, the US National Research CouncilÕs Committee on Planetary and Lunar Exploration (Space Studies Board) recommended that, to preserve pristine conditions on these three Jovian satellites for future astrobiological exploration, appropriate planetary protection measures should be triggered for the end of this mission. Solar system exploration is now advancing into the era of sample return (NRC, 1998; NRC, 2002, Quarantine), and the science of astrobiology is altering assumptions about the nature and boundaries of life as we know it (Fox, 2002; Wachterhauser, 2000). Over the past decade, scientists have made great progress in learning about the boundaries within which life can thrive on Earth (Cowen et al., 2003) – and about locations on or beneath the surface of other solar system bodies where Earth life might be able to survive and where indigenous life might exist as well (Chyba and Phillips, 2001; Kargel, 2004; Paige, 2005). Right now it looks like life can survive just about anywhere under just about any conditions (NRC, 2003; Nicholson et al., 2000). Solar system sample return missions are already in progress to bring back particles of the solar wind, comets and asteroids for scientific analysis. And in the not too distant future, perhaps in the next decade, space-faring nations are eventually expected to begin retrieving samples from the martian surface and subsurface, perhaps in the next decade (NRC, 1990). Planetary protection requirements have already been drafted to prevent the forward contamination of Mars and other bodies by Earth microbes and the backward contamination of Earth by possible martian extraterrestrial life (NRC, 2005). In response to the growing number of solar system exploration missions and expanding understanding of planets and life, the work of NASAÕs Planetary Protection Office is expanding, and interest in its work is growing. Thus the Planetary Protection Office is expanding its communication research efforts. Mars is of special interest to the international planetary protection community because of the history of water there. Planetary scientists have long believed that Mars may have had liquid water on its surface at some point in its history (Jakosky and Mellon, 2004; NRC, 2001). Some scientists consequently have considered that the planet may have hosted life as well (McKay et al., 1996; Thomas-Kperta et al., 2002). Missions launched to Mars over the past decade – Mars Pathfinder, Mars Global Surveyor, Mars Odyssey, the Mars Exploration Rovers, and Mars Express – have produced new evidence of large quantities of liquid water on the surface of Mars in the early history of the planet (Arvidson et al., 2005; Malin and Edgett, 2003; Mangold et al., 2004; Paige, 2005) and considerable stores of water ice on Mars today (Bibring et al., 2005; Mitrofanov et al., 2003; Titus et al., 2003). In addition, some scientists have recently claimed they see evidence of methane in the planetÕs atmosphere in quantities sufficient to suggest that biological activity might be producing it (Musser, 2004). Based on recent observations of the planet, a growing number of scientists are entertaining the possibility that liquid water – and perhaps even microbial life – may exist somewhere on Mars today (Kargel, 2004). Researchers have examined the potential for a natural interplanetary transfer of microorganisms by the high-velocity ejection of soil and rock resulting from planetary impacts of comets and other small bodies and concluded that if microbes have ever existed on Mars, their viable transfer to Earth would be not only possible but also highly probable. Viable transfer of Earth life to Mars is also believed to be possible. That is, microbial life from Earth could have been delivered to Mars via meteoric impact, and if microbial life ever evolved on early Mars, it could have been delivered to Earth in the same way (Gladman et al., 1996; Gladman and Burns, 1996; Melosh, 1984, 1985; Mileikowsky et al., 2000). L. Billings / Advances in Space Research 38 (2006) 2225–2231 Another issue that has recently surfaced in planetary protection is the possibility that Earth organisms may have already been delivered to Mars by human technology, given that three Soviet spacecraft (Mars 2, Mars 3, and Mars 6) and two NASA spacecraft (Mars Climate Orbiter and Mars Polar Lander) have already crashed on the planet. One proposal put forth to address the possibility of any contamination that might be caused by these crashes is remediation. It has been suggested that if life is ever detected on Mars, NASA should be prepared to reverse its Mars exploration campaign and remove all of the space hardware it has left on the surface of Mars, toward reducing that risk that any dormant bacteria surviving on these spacecraft might be transported to more hospitable subsurface environments. In light of current scientific understanding of Mars, measures for Mars sample return missions will be especially stringent, including the requirement for sterilization of all spacecraft components intended to come into contact with the surface of Mars and complete containment of returned martian samples until they are verified free of contamination. Avoiding forward contamination – that is, preventing human-caused microbial introductions to extraterrestrial environments – is necessary to preserve the planetary record of natural processes. And preventing back contamination is necessary to protect life on Earth from possible extraterrestrial life and to preserve the pristine quality of returned samples for scientific investigation. 3. Planetary protection communication research NASA communication about planetary protection to date has focused largely on interested members of the global space science community, particularly COSPAR, NASA, and the NRCÕs Space Studies Board. NASAÕs Planetary Protection Office has aimed to ensure that its scientific and bureaucratic constituencies are fully informed about planetary protection policies and procedures. The Office is now considering the needs and interests of public audiences and aiming to ensure that members of the planetary protection community are prepared to communicate with a variety of public audiences about issues relating to planetary protection. The scope of the content of communications about planetary protection is broad, encompassing a range of science disciplines (astrobiology, astronomy, biology, chemistry, microbiology, and planetary science), technology (for contamination detection and monitoring, sterilization, and containment), national and international law and policy, ethics, risk assessment, and more. Issues in planetary protection include technology requirements for sterilization, containment, and sample analysis; boundary conditions for life; implications of the use of space nuclear power and propulsion systems; international cooperation; and legal, regulatory and policy frameworks. The planetary protection program at NASA is especially interested in ensuring that it is able to meet public needs for 2227 information about possible biological contamination on a daily basis and in crisis situations. NASAÕs planetary protection officer characterizes his stance on communication, with specialist and non-specialist audiences, as ‘‘tell Õem early and often’’. The scientific community has endorsed this approach as well: in a 1992 report on Mars sample returns, the US National Research CouncilÕs Space Studies Board recommended, ‘‘Throughout any sample return program, the public should be openly informed of plans, activities, results and associated issues, etc. The most effective strategy for allaying fear and distrust is to inform early and often as the program unfolds’’ (NRC, 1992,). 3.1. Research from 1992 to 2002: expert audiences Communication research sponsored by the NASA planetary protection program began in 1992, initially focusing on informing expert audiences, addressing legal and ethical concerns, and understanding risk communication needs in the context of public decision making. Early analyses of planetary protection and public decision making (1992– 1994) identified a key message to be conveyed to expert audiences: planetary protection measures are an integral element of solar system exploration mission planning and must be integrated with mission plans from the start. That is, mission managers and others involved in solar system exploration must understand that planetary protection is mandatory, not optional. (NASAÕs Planetary Protection Officer has the authority to stop the launch of spacecraft if it is found to be non-compliant with planetary protection requirements.) This message is now widely accepted at NASA and in the broader space community. Early research also addressed societal concerns and led to more in-depth studies and journal papers (1995–1999) on risk and other ethical issues (Race, 1996, 1999; Race and MacGregor, 2000). Surveys and focus groups were employed to gather data on expert and non-expert views. In addition, the NASA Planetary Protection Office engaged in outreach to scientific and technical associations in an effort to convey the message that planetary protection applies to ‘‘all of the planets, all of the time’’. Further outreach to expert audiences (2000–2002) led to papers published in diverse scientific and technical journals, and preliminary outreach to general audiences, including story placements in media outlets such as the BBC, Discover magazine, and National Public Radio as well as the distribution of information to museums and planetariums. 3.2. Current research: communicating with public audiences In 2002, this communication research initiative expanded to examine theories and models of communication and review research in science and risk communication, the rhetoric of science, public understanding of science, and public opinion research as they relate to planetary protection. Current planetary protection communication research (2002–present) continues to address legal and ethical issues 2228 L. Billings / Advances in Space Research 38 (2006) 2225–2231 and communication within expert audiences, but it is also now exploring theories, models, and research findings that could contribute to a foundation for planetary protection communication strategy and planning and guide the development of communication tools. Among relevant research findings gleaned from the literature (Borchelt, 2001; Collins and Pinch, 1993; Dornan, 1988, 1990; Douglas and Wildavsky, 1982; Dunwoody and Peters, 1992; Flynn et al., 2001; Gregory and Miller, 1998; Hornig, 1992, 1993; Peters et al., 1997; Sandman, 2001a,b, 2002; Shoemaker and Reese, 1996; Valenti and Wilkins, 1995) are that:  ‘‘The public’’ is not a monolithic audience.  Public understanding of science does not ensure public appreciation or support for science.  Perceptions of reality can constitute reality, especially in communication about science and risk.  Public understanding of science and risk does not depend solely on the quantity or quality of information conveyed by experts to non-experts. It also depends in large part on the social context for the communication in question.  In addition to the provision of official statements and factual data, successful communication about risk requires validation of emotional responses and personal beliefs.  Trust is key to successful communication about risk.  Keys to establishing trust in communications about scientific and technological risks are caring and empathy, honesty and openness, commitment and dedication, competence and expertise.  Mass media play a key role in public discourse about science and risk, but audiences tap many other sources for information as well.  Experts and expertise serve a purpose in communication about science and risk but are not sufficient to establish effective communication.  Both journalists and scientists employ professional values and practices that are different and sometimes conflict.  Science and scientists are not apolitical, objective, or value-free, and though they hold privileged cultural status as arbiters of knowledge, this status alone does not assure them the publicÕs trust.  Journalism and journalists purport to be objective, but they are not free of the influence of personal, professional and institutional values and interests. In consideration of these and other relevant research findings, the communication strategy developed for NASAÕs planetary protection program characterizes communication as contextual and contingent. This strategy envisions communication as an ongoing, interactive process occurring in specific social contexts and serving material and symbolic ends. The strategy rests on the assumption that communication takes place in complex networks of interacting exchanges by means of mass media, local media and other public channels as well as interpersonal contacts (Burke, 1959, 1973; Carey, 1993; Lewenstein, 2003). The aim of this communication strategy is to expand public discourse on planetary protection, accommodate multiple perspectives, validate expert and local knowledge, and enable public participation (Freire, 1994; Servaes et al., 1996). Such a strategy, resting on an open, contextual, interactive model of communication, is intended to enable more effective communication about science and risk; greater public engagement; and more informed public decision making. In addition to a communication strategy, a planetary protection risk communication plan has been drafted, including a contingency plan for crisis situations that offers the NASA planetary protection officer the options of employing risk communication contingency teams and citizen advisory groups as needed. Identification, characterization, and cultivation of audiences is also important in planetary protection communication strategy and planning. Intra-agency, interagency, congressional, and intergovernmental communications must be considered; and non-governmental organizations and interest groups, mass media, students and community groups are other potentially important audiences. Preliminary audience research is now under way. Among the audiences identified for possible cultivation are environmental groups and public health officials. 4. Challenges Successful implementation of the communication strategy developed for NASAÕs planetary protection program depends on the ongoing participation of NASA officials, program managers, public affairs officers, external and legislative relations representatives, education and outreach specialists, and others inside and outside the agency. Coordination among organizations and individuals who may be called upon to address various audiences about planetary protection, toward ensuring that current, comprehensive, and consistent information is available to all interested parties at all times, is a challenge. Members of the planetary protection community may set the example for NASA and other involved government representatives, as well as other members of the science community, in their willingness and ability to employ this broadly inclusive and intentionally flexible communication strategy. Experience at other US government agencies has shown that an open, interactive approach to communication – an overarching concept encompassing practices variously referred to as public engagement, public participation, community involvement, joint fact finding, public dialogue, consensus decision making and collaborative problem solving – can be effective. The US Environmental Protection Agency has a public involvement policy, and the US Department of Energy also has a public participation policy in place. The Consensus Council, Inc., has reported on some success stories (http://www.agree.org). The Policy L. Billings / Advances in Space Research 38 (2006) 2225–2231 Consensus Initiative has also reported on progress in public policy decision making and dispute resolution by consensus (http://www.policyconsensus.org). The Dialogue to Action Initiative offers information on progress in public dialogue and public engagement (http://www.thataway.org/dialogue/). And Public Agenda offers guidelines for and case studies on public engagement (http:// www.publicagenda.org). Experience also has shown, however, that there may be resistance to implementing such an approach, especially at top management or political levels, particularly if such an approach represents a change in practices and because participatory practices tend to involve power-sharing. The US Army, Centers for Disease Control, Department of Energy, Environmental Protection Agency, and Geological Survey have variously conducted research and adopted policies relating to participatory communication, and some agencies have employed participatory practices, typically at the local level. Examining research on and experience with various forms of participatory communication in government agencies, especially in the context of dealing with risks, may yield some useful insights (Raloff, 1998; Tinker, 1996). Another challenge in planetary protection communication research is associated with the advent of Mars sample returns (NRC, 2002, Quarantine). Such a mission will be very expensive and highly complex, and sample containment upon return to Earth will require strict security procedures. Criteria for Mars sample handling before release from post-flight containment are established in ‘‘A Draft Test Protocol for Detecting Possible Biohazards in Martian Samples Returned to Earth’’ (Rummel et al., 2002). The NASA Planetary Protection Office has distributed this draft protocol to organizations and individuals representing a wide array of communities and interests for their consideration. Criteria for Mars sample containment and handling as described in the draft protocol will be updated continually, as warranted by new developments in science and technology. It is not yet known precisely when or where samples will be returned to Earth from Mars (or other planetary bodies with potential to support life). It is impossible to predict who will be in charge of NASAÕS planetary protection program, the planetary exploration program, and the overall agency of NASA if and when Mars sample return or other potentially sensitive planetary protection issues draw public attention. Thus it is impossible to predict how NASA would respond to such attention. But it is possible to be prepared for such an event. The risk communication plan drafted for planetary protection is designed to provide the NASA planetary protection officer considerable flexibility in dealing with any potential communication crises, including, for example, the options of creating planetary protection risk communication contingency teams and citizen advisory groups to deal with specific developments. But even with such contingency measures, this plan unavoidably contains considerable uncertainty. Communication planning, especially risk communication planning, in relation to planetary sam- 2229 ple return missions thus has a significant element of built-in uncertainty. Although NASA does not plan to launch a Mars sample return mission before the second decade of this century, preliminary design studies are already under way for a Mars sample return facility, which will be a Bio-Safety Level (BSL) 4 science laboratory. BSL-4 is the US governmentÕs designation for laboratories certified to contain the deadliest of microbes such as Ebola virus. Plans to build BSL-4 laboratories for biodefense research have prompted protests in some communities. The experiences of other government agencies in communicating with the public about BSL-4 facilities may offer some useful insights. The number-one need in communication with public audiences about planetary protection is to establish and maintain credibility and trust. Current events can quickly change the context for communication about contamination and other risks, at any time and without warning, for better or worse. The communication strategy outlined here is intended to enable the NASA Planetary Protection Office to establish and maintain direct and continuous communication with all of its various audiences, building and sustaining continuity, credibility and trust by pursuing a consistent, constructive, inclusive approach to communications; ensuring full and timely disclosure; getting to know audiences; and acknowledging uncertainty. 5. Implementation First steps toward implementation of this communication strategy for planetary protection include development of a clear, concise and complete narrative explaining what planetary protection is and does, describing links with astrobiology and planetary exploration. Another useful step will be to examine ‘‘lessons learned’’ in relevant NASA communication campaigns for missions such as the Galileo mission to Jupiter and the Cassini-Huygens mission to Saturn, which raised public concerns about risks related to the use of radioisotope thermoelectric generators; and the Keck telescope outrigger project, which raised community concerns about public involvement in environmental impact assessments. Environmental and other anti-nuclear groups protested against the launch of Cassini because it was carrying a nuclear power source. Environmentalists and native Hawaiians took NASA to court over its plans for a Keck outrigger telescope project, and in 2003 the court ruled against NASA, observing that the agency did not give sufficient consideration to public concerns and directing the it to prepare a full-blown environmental impact statement for the project before proceeding with any work (Lum and Viotti, 2003; Dayton and Viotti, 2003). These cases may provide useful lessons for future NASA communications about environmental concerns that may arise in relation to planetary protection. NASAÕs Planetary Protection Office will continue to consult with the NRC, which already has offered extensive expert advice (NRC, 1992, 1997, 1998, 2000, 2005). 2230 L. Billings / Advances in Space Research 38 (2006) 2225–2231 A Planetary Protection Communication Steering Group has been formed to oversee the development and execution of communication strategy and plans, in consultation with the NASA Advisory Council Planetary Protection Advisory Committee and other experts as needed. Another recent step that NASAÕs Planetary Protection Office has taken toward ensuring that communication about any possible contamination risks associated with solar system exploration are timely and thorough is the offering of a threeday course on planetary protection policies and practices for those involved or otherwise interested in planetary protection activities. The aim of this course is to ensure that all who need or want to be are up to date on the latest scientific, technical, and policy developments in planetary protection. (As of June 2004, the NASA Planetary Protection Office had conducted this course in three locations – Baltimore, Maryland, Santa Cruz, California, and Basel, Switzerland, serving more than 100 students from government, industry, and academia. The course was offered at various sites in the US and Europe in 2005.) 6. Conclusion The goal of the communication strategy outlined here is to help the Planetary Protection Office identify and meet the needs of its various ‘‘publics’’ and aid fulfillment of NASAÕs statutory function to ‘‘provide for the widest practicable and appropriate dissemination of information concerning its activities and the results thereof’’ (Sec. 203 (a) (3), PL85-568, National Aeronautics and Space Act of 1958). An open, interactive and inclusive approach to communication is a democratic approach, in this authorÕs view. 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