Document 264402

Adv Space Res Vol 26, No 12, pp 1901-1909,200O
Q 2001 COSPAR Pubhshed by Elsewer Scmce Ltd All nghts reserved
www elsevier nlflocatelasr
Pnnted m Great Bntaln
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PI1 SO273-1177(00)00160-5
Margaret S Race’ and Donald G Ma&t-ego?
‘SETI Institute, Mountan View, CA 94549, USA
2DecrslonResearch, Inc., andMacGregor-Bates, Inc., Eugene, OR 97401, USA
Plamung for extraterrestnal sample returns-- whether from Mars or other solar system bodes-- must be
done m a way that integrates planetary protection concerns with the usual mission techmcal and scientrfic
considerations Understanding and addressing legitimate societal concerns about the possible risks of
sample return will be a critical part of the public decision making process ahead This paper presents the
results of two studies, one with lay audiences, the other with expert microbiologtsts designed to gather
mforrnation on attitudes and concerns about sample return nsks and planetary protection Focus group
interviews with lay subjects, using generic information about Mars sample return and a prehmmary
environmental impact assessment, were designed to obtain an mdrcation of how the factual content is
perceived and understood by the publtc A research survey of rmcrobrologtsts gathered mformation on
experts’ views and attitudes about sample return nsk management approaches and space exploration
risks These findings, combmed with earlier research results on risk perception, will be useful m
identifymg levels of concern and potential conflicts m understandmg between experts and the public
about sample return risks The mformation ~111be helpful m gmdmg development of the environmental
impact statement and also has apphcabihty to proposals for sample return from other solar system bodies
where screntrtic uncertamty about extraterrestrial life may persist at the time of mrssion plannmg
Q 2001 COSPAR Published by Elsevler Science Ltd All rights reserved
NASA’s plans for Mars exploratron early m the next nnllenmum include a sample return nnssion that will
launch around 2005 and return soils, rocks and atmospherrc samples to Earth around 2008 In response
to both mtematronal treaties and domestic laws, numerous planetary protection controls will be
incorporated into the rmssion design along with traditional technical and scientific considerations
(DrVmcenzi et al, 1998) The ultimate success of a sample return mission may also depend on
understandmg how the techmcal and scientific aspects of planetary protectron interact with legal
requirements and societal concerns about mtssion activities m space and on Earth (Race, 1998)
Understanding and addressmg legitimate societal concerns about the possible risks of sample return will
be a crmcal part of the public decision making process ahead
In preparation for public oversight and
involvement m decision makmg about sample return, planmng must focus on legal compliance and
procedural requirements, as well as pubhc concerns and perceptions
Even if all procedural and
admmlstrauve requirements are fulfilled m advance of launch and all the technical and scientific experts
are satisfied that the mission has been planned and designed appropriately, the public has a legitimate
right to scrutmize the rmssion before giving its mformed consent to proceed
M S Race and D G MacGregor
Because mformation about the mission will be made available either through formal documents like the
environmental impact statement (EIS) or via the mass media, it 1s important that NASA understand the
nature and extent of pubhc concerns about mission risks Recent experiences with several controversial
missions have highlighted the necessity of addressing public concerns and perceptions seriously (e g ,
protests about nuclear materials and possible launch or Earth fly-by accidents assocrated with the Cassuu,
Galileo and Ulysses mrssions) Risk communication plans must anticipate the preparation of mformation
for varied audiences and diverse venues, ranging from the courts, to the mass medta, the Internet and
NASA’s own outreach materials In recogmtton of the potentially controversial nature of sample return
proposals, NASA has acknowledged the importance of learning as much as possrble about pubhc
perceptions of extraterrestnal exploration and sample return risks
These perceptions will, over time,
form important input to the development of nsk management strategies for future sample return mtssions
A series of research surveys conducted pnor to the announcement about possible fossil hfe in a Martmn
meteorite has provided a baseline of mformation useful for Mars sample return planmng (MacGregor and
Slavic, 1994, 1995, Mac Gregor et al, 1996) This earlier research studied both lay audiences and life
science experts regarding then attitudes and perceptions on planetary protection and the risks of Mars
sample return missions
Since that earher risk perception research, the public has been exposed to
extensive mass media coverage about Mars exploration and the potential for extraterrestrial life (e g,
Pathfinder, Global Surveyor and other missions to Mars, Galileo mission and Europan ice and oceans,
etc ) In light of this increased general exposure, it wrll be tmportant to keep abreast of public knowledge
and attitudes dunng mission planning This paper presents the results of two addittonal research studies
on risk perception and attitudes, the first mvolvmg small focus group interviews with lay audiences, and
the other mvolvmg a research survey of microbiologists
For the upcommg Mars sample return mission, NASA will pubhsh an environmental impact statement
(EIS), an official document designed to comply with legal requirements of the Nattonal Environmental
Policy Act (NEPA) The NEPA process is Intended to disclose complete mformatlon about proposed
government actions and to address antrcipated environmental impacts The EIS w-illpresent mformatton
about the proposed misston, covermg topics such as mission archttecture, hardware and spacecraft data.,
Based on risk
sample handling plans, risk assessments, accident scenarios, and other required facts
perception research and experiences with other controversial proposals, tt IS likely that mass media and
public attention will focus on questions related to environmental concerns and health and safety issues,
parttcularly from the time of reentry through sample quarantme and testmg (Race, 1998)
In order to gather additional mformation about the nature of pubhc concerns, a six-member focus group
and a series of SIXm-depth mtervtews were conducted m 1998 Participants included both males and
females, rangmg m age from 18 to 46 years, all of whom had some university background The focus
group was conducted with SIXparticipants, allowing sufficient opportumty for mdivtduals to share their
views and comments
The focus group approach and interview approach, while not havmg scientific
vahdrty m terms of its sampling procedures, provides a relatively low-cost methodology for ehcitmg
responses to novel stirnull for which previous research is unavailable Focus group and mdivtdual
interview studies produce a text narrative of participants’ reactions that can be content analyzed and
excerpted for use m generatmg research hypotheses and potential lines of research Both techniques are
valuable tools for the development of larger-scale studies using survey methodologies
Particrpants were gtven background mformation ahead of time that mcluded a videotape on NASA’s plans
for Mars exploration and future Mars missions Other background mformation included a notebook vvlth
a selection of pubhshed articles and a mock-up of an environmental assessment based on a generic
mission architecture Participants were asked to view the materials on then own and return later for a
Pubhc Attitude and Sample Return Mtsslons
discussion or mterview session with a professional facilitator who asked questions about their views and
concerns regarding NASA’s plans Dunng the sessions, none of the participants expressed any difficulty
comprehendmg materials, though they tended to find the environmental assessment repetitious and
relatively umnterestmg
In general, respondents did not view Mars sample return itself as a major societal nsk issue They had
difficulty makmg many comments about the nature and levels of the nsk associated wrth sample return
and generally felt that “smce ‘we’don’t know much, there IS a lot to learn ” However, this also translated
at trmes mto a respect for caution For example, one respondent expressed the need to be “really humble
because they don’t know what they are gomg to find or what’s going to happen, or rf anything’s gonna
go wrong ” In ad&tion, respondents expressed a desire to know more about the actual nsk data itself,
while at the same time questionmg whether NASA was objective enough to present the data m an
unbiased manner They essentially distrusted nsk mformation from a proposmg agency like NASA and
expressed preference for an analysis by an umnvolved party, such as an environmental group
Several other concerns emerged from the discussion not directly related to sample return but wnh
possible imphcations for future public outreach Surpnsmgly, biological contammation risks did not
dommate their concerns Others nsks mentioned m the mock environmental assessment, particularly
nuclear risks, loomed much larger than sample return itself Participants expressed concern about the
presence of nuclear materials that nnght be carned on the missron m the form of RI-IU’s (radioisotope
heater umts), similar to those carried on the Pathfinder mission Tlns result IS generally consistent v&h
the sizable body of research on public perception of technological nsks and hazards that has found nuclear
risks to be perceived m extreme terms and to be of unusually strong concern
A general perception that arose from the interviews pertained to the value of the rmssron, and of space
research m general Participants questioned the pomt of the mission based on the benefit of scientific
knowledge, compared with other ways to benefit people on Earth They expressed the view that space
exploration and research seem expensive and self-serving m relation to other programs that could generate
greater progress for society P.espondents who questioned the benefits of space research also had a
difficult time generating examples of spin-offs from space research Furthermore, they saw few concrete
lmks between space research and our current understandmg of the Earth’s environment, without
promptmg (e g , remote imaging, weather prediction, etc )
These hmrted findmgs do not mean that the pubhc will be msensmve to biological risk mformation
presented m the media People will tend to take their cue regardmg what they should be concerned about
from the media and screntrfic oprmons expressed m the media The results from the focus group and
individual mtervrews suggest that people have relatively little basis for concern about potential brologtcal
nsks associated with sample return and are likely (at the present time) to be more concerned about more
tradrtronal technological nsks, such as nuclear risks associated with space activities The lack of a solid
perception of benefits and values associated with space research is, however, quite troubling and
potentially of great sigmficance in gaming broad public acceptance of space research Research on public
acceptance of technological risks has generally found that nsk acceptance IS a function of perceived net
value (posmve vs negative) of a technology’s risks and benefits . When benefits are perceived as
extremely low (or non-existent), Judgments of acceptabihty are likely to be based almost exclusively on
perception of risk
Many of the problems faced by risk-management organizations are the result of diffenng perceptions of
nsk and risk management between the general public and scientific experts (e g , MacGregor et al, m
press, and 1992) Indeed, a consistent finding m nsk perception studies IS the heavy reliance that lay
M S Race and D G MacGregor
people place upon scientific disagreements as mdrcative of the degree to which they should be concerned
about a risk issue (e g , Slavic et al, 1980, Slavic, 1987, Pidgeon, et al., 1992) In essence, if experts
don’t know enough to agree, then there must be a problem worthy of attention
Currently, scientrfic understandmg of extraterrestrial organisms IS particularly low (or non-existent), the
potential consequences of exposure to (or contammation by) such organisms (if they exist) is vntually
unknown or speculative, and the mechanisms for managing the nsks of such exposure are either novel,
complex, or relatively untested As new mformatton IS discovered about extremophiles’ on Earth, and as
additional data are generated from space exploratron missrons, current scientific attitudes and perceptions
about extraterrestrtal life and attendant risks are likely to change rapidly This means that the public is
likely to witness a vigorous debate among scientists about extraterrestnal life This anticipated public
debate has important tmphcations for the form and content of future risk commumcatton messages
MacGregor, et al (1998) studied perceptions of planetary protection pnor to announcements about
possible fossil hfe inside a Martian meteorite Results at that time indicated that the pubhc and experts
alike were uncertam about the posstbdmes of hfe on Mars, were concerned about planetary cross
contammation, and had strong feelings that Martian samples should be considered hazardous until proven
otherwise They also beheved that NASA should take a cautious approach m dealing with materrals that
pose potential or unknown biological hazards In then studies both scientists’ and non-sctentists’ vtews of
planetary protection and the possible threats posed to Earth’s environment by Mars samples were strongly
related to the perceived value of space exploration, and to Judgments about the morality associated with
exchanging hfe between planets However, scientists tended to be more conservatrve than non-scientists
in Judging the hazardousness of potential Marhan life
In these earlier risk perception studres, the expert views were based on surveys of a broad group of life
scientists, mcludmg biologists, zoologists, and general environmental scientists with a common Interest m
‘exotic species ’ However, tf life exists elsewhere m the solar system, it IS likely to be mtcrobtal m
+nature, and methods of contarmng, handling and analyzmg samples returned from Mars (or other planets)
wdl be based on microbiologtcal sciences Thus microbiologists represent a class of life sctentists wtth
expertise most relevant to questions about the nature of putative extraterrestnal life and recommendations
for handling it Accordmgly, then perceptions about biohazard risks and views about planetary protection
will be important m future risk management decisions In addition, then explanations will be an
important part of risk commumcation messages that are needed to assure the public about the adequacy of
sample return preparations
In order to gather addtttonal expert mformation, a study was designed to query rmcrobiologists m
partrcular about then views on the risks and adequacy of measures associated wtth space exploration,
planetary protection and current sample return plans A four-page questionnaire was developed by
updating and revtsmg the earlier risk survey Questions were designed to assess a number of concepts
relatmg to planetary protection, mcludmg behefs about hfe elsewhere m the solar system, perception of
sample return risks, and perceived adequacy of risk management The survey was administered to a
sample of mtcrobtologists attending the annual meeting of the American Soaety of Microbiology held m
Atlanta m May, 1998
Questionnaires were administered at a special five-session colloqumm titled
“Prospectmg for Extraterrestrial Mcroorgamsms and the Ongm of Life An Exercise m Astrobiology ”
“Extremophlles” are nucrobml orgamsms that hve or remam viable at extreme con&t~ons (lugh or low)--- for example,
temperature, radmt~on, desnxation, nutnents, sahmty, pressure, hght etc Currently there IS great sc~en&ficmterest m these
orgamsms and how they persist m margmal con&t~ons where hvmg systems can barely fimaon
Some examples of
extremophlles mclude bacterml spores m Menan pexmafrost, bactena hvmg ms~de rocks m AnQrct~ca, bacterm hvmg m nearbollmg water at the deep sea vents, or m thermal hot sprmgs, bactetra that w&stand mtense doses of Won
on Earth or m
space, etc )
Pubhc Attitude and Sample Return Mtsslons
All of the survey items
Data were also collected simultaneously at a non-related session for comparison
required only categorical responses (e g , strongly agree, agree, disagree, strongly disagree) In addition,
respondents were asked to provide general biographical informatron about themselves (e g , gender, age,
professional orrentation) A total of 201 completed surveys were returned, from which the findings
below have been drawn Comprehensive information on study methodology and overall results are
provided elsewhere (MacGregor and Race, 1998)
Mrcrobiologtsts’ Survey Results
Behefs About Life Elsewhere Though the existence of life elsewhere m the solar system is a matter still
far from screntific conclusion, research has long been underway to discover where conditions rmght exist
for such life Mrcroblologrsts were asked their opimon concermng the possrbtlrty of hfe on other planets
in our solar system, as well as the possrbihty of life on Mars (Figure 1) In general, respondents were
optrmrstrc about the exrstence of life on other planets m our solar system Over half (58 2%) of the
respondents agreed that life might exist m such a broad expanse, while about one-third mdmated “don’t
know” (3 1 3%) When the domain of reference was more restricted, however, agreement tended to drop
Only 40 3% agreed that rt is highly probable that life exrsts on Mars Again, approximately a third
(32 3%) indicated “don’t know ’
Percentrons of Risk To place space exploratron and sample return nsks m a broader context, respondents
were asked to rate 28 Qfferent societal actrvitres and technologies by their level of perceived risk These
included space-related nsks (e g , sample return, satellite debris, asteroids), nsks of brologrcal ongm (e g ,
bloodborne parasites, sexually transmitted diseases (STD’s), bacteria in food), and other socretal nsks
(e g , nuclear power plants, radon, global warming) Table 1 shows the percentage of respondents grvmg
a “moderate” or “high” nsk rating for each of the hazard items
Perhaps most stnkmg about the results shown m Table 1 1s the relatively low positron occupied by all of
the space-related risks,, mcludmg brological and/or ecologrcal risks of Mars samples As a category of
nsks, these drew relatively little concern when presented m the context of a larger societal nsk prcture
Thrs does not mean, however, that biological nsks of space activities are perceived as ummportant or
insigmficant, only that when viewed from the perspective of a number of hazards to whrch soctety is
exposed, space-related nsks do not loom large Most of the other hazards shown m Table 1 have been
demonstrated to result m death, mlury or illness For space-related hazards, however, few (if any)
members of society at large have been shown to have suffered physrcal loss
Life, in some form,
exists on other
planets in our solar
It IShighly probable
that life, in some
form, exists on
Beliefs about life elsewhere
M S Race and D G MacGregor
Table 1 M~cmbdog~sts'
Perceptronof Rtsk
1 % ‘Moderate )
Hazard Item
1 or’H~gh’ Wsk 1
I NuclearFWerPlants
1 Food Irradtabon
Hazard Item
Pesbdes in Food
Broterronsmw/PathogenicAgents J
kttxme Duzea&lndcor kr Quakty 1
1 %‘Moderate’ 1
1 or ‘High’ Rsk
I Xenotmnsplantatton
52 2
Food Addrtrves
I Ecological Drsruptronfrom Mars samples I
I Pathoganrcctyfrom Mars samples
Perceutron of Samnle Return Rrsks Specific items were mcluded in the survey about the threat posed by
possrble life on Mars, and sclentrsts’ ability to predict such risks (Figure 2)
There was a great deal of
uncertamty about whether life on Mars could pose a biologrcal threat to Earth, with almost half of the
respondents (42 8%) indicating “don’t know ” More respondents tended to disagree (34 4%) that Martian
life (if it exists) poses no threat to life on Earth than to agree (22 9%) Thus, respondents were generally
cautrous about the potential for possible Martian life to be ecologically hazardous, perhaps in part because
the question itself was posed as “no threat ” In terms of our ability to predrct wrth reasonable certainty
how hfe elsewhere would impact Earth’s environment (see Figure 2), a large majority disagreed (71 2%)
that current scientrfic understandmg of microbiology 1s sufIicient to make such predictions Only 10 4%
gave a “don’t know” response
Overall, respondents were quite cautious about putative Martian life posing “no threat” to Earth’s
environment, and cautious as well about samples returned from other planets These views are generally
consrstent with the strongly-expressed attitude that the current state of rmcrobtal science IS msufftcrent to
make reasonably certain predrctions about how extraterrestrial blota might impact the terrestrial
If there IS life on Mars,
it poses no threat to kfe
on our planet
Our current screntrfic
understanding of
mrcroblology IS sufficient
to predrct wrth
reasonable certainty how
life elsewhere n our
solar system, should it
exist, could impact our
environment If returned
in samples to Earth
q Disagree
Fig 2
of Sample Return Risks
+ Strongly Disagree
Public Attitude and Sample Return Missions
Risk management approaches all mvolve methods of
risk characterization and assessment These methods are intended to provide a basis for evaluating and
classtfymg risks for the purposes of undertaking appropriate protective or rmttgatrve measures Perhaps
the simplest of risk characterrzation approaches mvolves a judgment of whether somethmg is hazardous
Respondents were asked to indicate whether samples from Mars should be considered as hazardous, and
whether experiments done on Mars will be sufficient to determine if it is safe to bring materials back to
Respondents were generally m strong agreement that materials returned to Earth from Mars should be
Only 1 5% of respondents indicated “don’t
considered hazardous until proven otherwise (Table 2)
know,” suggestmg a very low level of uncertamty However, respondents were not particularly confident
m the potential for experiments done on the Martian surface to sufficiently determme the safety of Mars
samples, over half (58 2%) dmgreed that such experiments would be adequate However, a fairly large
portion (21 9%) mdicated that they “don’t know ” These results tend to suggest that respondents prefer a
cautrous approach to nsk assessment, and generally prefer not to rely on zn sztu methods of nsk
Adequacy of Bioprotectton
Sample return missions wtll mvolve biocontamment and quarantme of
materials during analysis and testing, whether or not they ultrmately discover extraterrestrial life
Returned matenals will stay m containment unttl they are proven non-hazardous to Earth’s environment
Respondents were asked to indicate the “degree of adequacy” of current methods for quarantmmg and
bioprotection to accomplish the goals of sample characterization, life detection, and biohazard testing
In general, respondents were optimistic that current approaches to brologrcal risk
(Figure 3)
management are satisfactory For each of the three goals, about half the respondents indicated that current
methods are either moderately or highly adequate However, about a third of respondents indicated “don’t
know,” suggestmg either they were unaware of the methods or uncertam about then adequacy
with regard to samples of matenala returned to Earth from
other planets, m your wew how adequate are current
methods of quarantmmg and bloprotection for
Life detection?
75% 100%
FIN 3 Adequacy of Bloprotection
M S Race and D G MacGregor
Trust m Rrsk Management Though sample return rmssrons may involve mtematronal partners, the major
responsrbrhty for nsk management decisions concerning planetary protection ~111rest wtth NASA The
prospects for successful rrsk management rely m part on the trust that the public and experts hold m rusk
management mstttuttons (e g , Slovtc, 1993) Respondents in the study were asked to indicate the degree
to which they trust NASA to accomphsh a number of goals, ranging from successfully completing a Mars
sample return mission, to commumcatmg with the public about planetary contaminatron nsks (Table 3)
Table 3 Percewd
In general, respondents were qmte posrtrve and trustmg m NASA’s ability to successfully complete a
Mars sample return rmssion Though they were also posttrve about NASA’s ability to protect Earth’s
brosphere as part of sample return (1e , avotdance of back contammatron), they were less trustmg m
NASA to adequately accomplish protection against forward contammatron This difference could reflect
relative exposure to dlscussron m the colloquium, which largely dealt wrth planetary protection of Earth,
and not wrth steps taken to guard agamst contammation of the Martran environment
In terms of workmg wtth the public, respondents were more trustmg of NASA to respect pubhc values
concemmg space exploration than they were to honestly mform the pubhc about nsks from planetary
contammatron We speculate that the values questton gamed greater positive endorsement because it
mcluded both benefit and risk Issues, whereas the mformmg question mentioned only nsks This suggests
that among this group of respondents there may be some concerns about the adequacy to whrch risk issues
are conceptuahzed and/or commumcated to the public
Space exploration to study the ongms of life 1s a challenging endeavor, comphcated by the
mterdtsctplmary nature of the sctenttfic questions at issue Judgments about the adequacy of measures
taken to ensure the protectton of Earth’s biosphere durmg various phases of sample return missions wrll be
part of the decision making process, as well as a matter of mtense public concern and mterest Yet, at
least m the early decades of such missions, the deasrons will be largely a matter of expert scientrfic
opmton and speculation Focus group stuQes and survey research with lay audiences have shown the
pubhc’s general lack of knowledge about extraterrestrial life and the degree to which it may pose a nsk to
Earth Whrle they do not view sample return risks as a ma..or nsk issue, lay audiences nonetheless urge a
conservative approach that consrders returned materials as hazardous until proven otherwrse Risk
perceptron studies of mrcroblologists revealed a stmilarly cautronary approach They, too, support the
need to regard hfe elsewhere (should it be discovered) as hazardous until proven otherwise The majortty
of mrcrobrologists m this sample were also conservative regardmg the ability of scientists to make
confident predrctrons about how hfe elsewhere could impact the envnonment and brota of Earth
However, open questions remam regarding such vrews and opmrons For the most part, knowledge and
awareness of planetary exploratron 1srelatively new We have little firm evidence thus far that hfe exists
on other planets in our solar system, thus the cautious views expressed by respondents m the present study
of mrcrobiologrsts reflect the professional responsibrhty that most members of sctenttfic groups would
express when faced with a paucity of real data Deeper questions concern how such views would be
Pubhc Attitude and Sample Return Mlsslons
modified m light of future data that could suggest the possrbrhty, but not the confirmation, that hfe on
Mars 1s simrlar in its basic nature to rmcrobral hfe on Earth Interpretatron of the data will be
screntrfically challenging m the face of questions about false posrtrves and the effectiveness of techmcal
measures for planetary protection, then cost and feasrbihty
As NASA and socrety move forward wrth space exploration efforts, new data wrll emerge to inform and
enrrch screntrfic views We speculate that the coming decades will see an mcreasmgly vigorous screntrfic
discussion wrthm the mrcrobrologrcal and envrronmental commumtres concermng planetary exploratron
and planetary protection Informatron on the facts and uncertamtres surroundmg this debate will be an
important part of risk commumcatron messages conveyed to the public vra the mass media, the mternet
and m documents like the EIS Acknowledgmg and addressmg the levels of concern, and understandmg
potential confhcts between experts and the pubhc will be essential for developing public support and
confidence about risk management approaches and sample return decisrons
This research was sup orted m part by the NASA and SET1 Institute under NASA Grant #NAG 2-986
(Subcontract #986-97 op1) to Deasion Science Research Instttute, Inc The authors would like to thank the
members of the American Soaety of Mrcrobiology who participated m the study
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