The hammer of Hawking: The impact of celebrity scientists, the intent of extraterrestrials and the public perception of astrobiology
First Monday

The hammer of Hawking: The impact of celebrity scientists, the intent of extraterrestrials and the public perception of astrobiology by Rich Gazan

This paper assesses the impact of theoretical physicist Stephen Hawking’s warning about the possibly malicious intent of extraterrestrial visitors on the public opinion of the search for life in the universe, which is the domain of the interdisciplinary science of astrobiology. Using Web content analysis and sentiment analysis methods, 13 distinct categories of opinion are proposed, suggesting the role of Web comments as both public forums and naturalistic data sources. The results suggest that a significant percentage of those studied agreed with Hawking purely on the merits of his reputation, but those who disagreed tended to claim that Hawking’s argument failed logically or scientifically. How cross–domain authority manifests on the Web, and the influence of celebrity scientists on the public perception of astrobiology, are discussed.


1. Introduction
2. Background
3. Method
4. Results and discussion
5. Conclusion



1. Introduction

Space scientists have always maintained something of a love-hate relationship with science fiction. Many if not most scientists who work in this area had their initial interest in science kindled by the imaginative renderings of worlds that never were (see, for example, Locke, 2005), and the U.S. National Aeronautics and Space Administration (NASA) openly embraced the linkage by naming its initial space shuttle prototype after the fictional U.S.S. Enterprise. While effective public outreach usually requires emphasizing space science’s exciting possibilities over its often–tedious practice, as with most sciences, public opinion is buffeted by many winds largely or entirely outside scientists’ control. For example, while it may have been difficult to justify the enormous economic and intellectual capital required to send an astronaut to the Moon on purely scientific grounds, the political concerns of the Cold War added a sufficiently resonant sense of social urgency to the effort, and the space program of the 1960s enjoyed fairly widespread popular support. Scientific authority, political will and gamesmanship, mass media, science fiction, intellectual wonder and simple fear are all elements that shape popular conceptions of the exploration of space, and expectations of what we might find there.

This paper reports on the initial phase of a larger participant observation designed to learn more about the portability of expertise from scientific to Web environments, and the public perception of astrobiology. The ways in which astrobiologists frame and study questions of life in the universe are contrasted with those raised by physicist Stephen Hawking, and those of close to 1,500 people who discussed his opinion on three popular Web sites. The extent to which Hawking, while engaging in speculation outside his area of scientific expertise, can influence public opinion is offered as an example of the potential power of an individual who wields considerable social capital at the confluence of several domains: science, mass media, and to an extent, science fiction.



2. Background

While adopting a critical view about the usefulness of public involvement in scientific funding priorities, Rowe, et al. (2010) describe a pilot study of public engagement with scientists around verbal proposals of U.K. health policy proposals, and found that both the content of the policy and the reported likeability of the person delivering it had an influence on funding recommendations. Horlick–Jones, et al. (2007), writing on citizen engagement processes, balance the risks of “irrational” public perceptions as a threat to sound policy with the validity of lay epidemiology. The community of scholars in astrobiology has a vested interest in understanding how the public perceives the search for life in the universe. While a very small proportion of the population may watch the NASA television channel, or read Space magazine for regular updates of the latest scientific discoveries, most people pay attention only when a report reaches a more mainstream source, such as CNN or the Yahoo! home page. Farry and Kirby (2012) propose that space–related television content, with its inherent drama and linkage with celebrity scientists, was a critical component of the survival and success of the BBC in the 1950s and 1960s.

Nisbet and Goidel (2007) use framing theory to describe one way mass media emphasizes and de–emphasizes certain aspects of scientific issues and thus exerts significant influence on how citizens judge controversial science (Schön and Rein, 1994). Their study focused on embryonic stem cell research, and suggested that a methodological blend of qualitative ethnographic research and quantitative survey research can provide a complete picture of people’s value predispositions. Similarly, while distinguishing diverse models of public understanding of science (PUS), Bauer, et al. (2007) call for an expansion of data streams, particularly from mass media sources, to better inform PUS research. They find that qualitative research can suggest trends in individuals’ opinion and awareness of science, and call for integration and analysis of longitudinal databases and additional data streams. The source and method used in the present study addresses this gap, offering a strategy to capture a naturalistic snapshot of how individuals react to, and interact around, science and its perceived risks, as presented through mass media and the Web.


The majority of scientists studying the possibility of extraterrestrial life are immersed in questions about the conditions and probabilities of life elsewhere, including the genesis or delivery of liquid water to early earth as a precondition for the evolution of life, identifying possibly habitable extrasolar planets, understanding the molecular, genetic and biochemical mechanisms of evolution and environmental adaptation, and the general physical and chemical principles underlying the origins of life (NASA Astrobiology Institute, 2008). For example, if the Mars exploration rovers Curiosity and Opportunity discover indisputable fossilized evidence of even long–extinct microbial life, it would be an astounding find, more than most in the field of astrobiology would have ever reasonably hoped for. Imagining contact with extraterrestrial beings is certainly a staple in the conversational cabinets of most astrobiologists, but such speculation is entirely outside of the realm of the “real science” of astrobiology.

For the scientists working in the area, this distinction is especially important to preserve. Astrobiology is a relatively new area of study in its own right, with a small core corpus of published literature, and few dedicated journals, conferences or academic departments. For example, Pennsylvania State University and the University of Washington offer interdisciplinary Ph.D. programs in astrobiology that are integrated with other disciplines, and other universities offer astrobiology graduate certificates (University of Colorado at Boulder) or graduate minors (University of Arizona). Like most young interdisciplinary fields, the lack of an institutional support structure makes gaining both academic purchase and research funding difficult. Most scientists come to astrobiology via a more established field, and apply their experience and interests to a component of astrobiology’s problems, while maintaining their core academic identities elsewhere (Klein, 1990). Among the goals of the NASA Astrobiology Institute (NAI) are education and outreach, and here as well there is a balance to be maintained between strict factual reportage and informed speculation. Most NASA press releases substitute an artist’s conception or computer–enhanced rendering to illustrate a new finding, since the original image may be extremely difficult to discern, or may simply not look as exciting.

Risk, threat and fear

From a funding standpoint, both the Astrobiology Institute and NASA as a whole must compete for relevance in the public eye. Arguments for and against NASA’s existence usually center less on scientific merit and more around earthly problems as more worthy of public funding. However, when NASA efforts can be linked with terrestrial concerns, such as the Space Race of the late 1950s and 1960s, or the more recent awareness of the risks of “doomsday” asteroids colliding with the Earth, the equation changes. Interest in scientific issues is related to perceived risk and perceived uncertainty (Powell, et al., 2007). In short, fear gets funded.

Nerlich and James (2009) discuss how the discourse of catastrophe has become increasingly attached to scientific issues such as climate change, antibiotic resistance, biological warfare and microbial “superbug” pandemics. The authors, following the work of Weingart (1998), look at how words such as war, apocalypse, killer and battle are used willfully and intentionally by the researchers they interviewed, as a way to galvanize public attention and produce changes in policy, funding and behavior. Gusterson (1999) conducted a discourse analysis of research in security studies, and identifies an underlying self–reinforcing narrative that the Cold War could continue indefinitely, perpetuating cultural insecurity. While the dangers may be real, the likelihood of the worst–case scenario is often overstated by those positioned to benefit from the ongoing quest to identify and reduce risk.

Petersen, et al. (2009) interviewed scientists to elicit their views on media coverage of nanotechnology, focusing on the elements of popularization scientists thought media reports should entail. New technologies and scientific discoveries are especially attractive to news media, whose existence depends on a constant input of novelty, but both benefits and dangers are routinely overemphasized, as “intense discursive struggles” between contending stakeholders occur (Allan, et al., 2005; Nisbet, et al., 2003), with the goal of influencing public opinion. Sensational and/or speculative media coverage may have some positive aspects insofar as they attract initial public attention, but at the expense of undermining scientists’ authority, and providing a misleading impression of the rewards and risks of their effort.

The possibility of a “doomsday” asteroid or other object colliding with Earth and extinguishing all life has always existed, but public attention has been galvanized as much through science fiction as through science. This paper’s title was inspired by two such works, Lucifer’s Hammer (Niven and Pournelle, 1977) and The Hammer of God (Clarke, 1993), where objects from space are set to collide with Earth, with predictably apocalyptic effects. Two major studio movies about Earth impacts, Armageddon and Deep Impact, were released in 1998, neatly coinciding with reports of the XF11 asteroid, which had been reported to be on a potential collision course with Earth in 2028. Movies and associated media coverage played a role in increasing both public awareness and NASA support for scientific projects designed to prevent such a collision [1], underscoring the importance of understanding influences on public opinion.

In 1992, NASA generated the Spaceguard Survey Report (NASA Ames Space Science Division, 1992) in response to a mandate by the U.S. Congress to detect asteroids and other near–Earth objects, and propose strategies to avoid cataclysmic impacts. In 1994, the goal was to identify and catalogue, within 10 years, the orbital characteristics of 90 percent of all comets and asteroids larger than one kilometer in diameter that cross the orbit of Earth. In 2005, the threshold of concern was tightened, and NASA’s current mandate is to detect all near–Earth objects with a diameter greater than 140 meters by the year 2020. Ground–based telescopes with shared international funding generally take ten or more years from proposal to completion, when their goals are primarily concerned with the advancement of knowledge (Association of Universities for Research in Astronomy, 2009). However, when a project’s goals enter the realm of planetary defense, the timetable accelerates. The first of four planned Panoramic Survey Telescope & Rapid Response System (Pan–STARRS) telescopes, which are designed to scan the skies each night seeking near–Earth objects, became operational in May 2010, just seven years after the initial grant proposal was funded. While NASA has yet to produce a fictional motion picture, the Pan–STARRS Web site ( includes a section called “Asteroid Threat,” with a subsection about how impacts have been portrayed in various science fiction movies (Pan–STARRS, 2011).

Mellor (2010) analysed media coverage of the threat of several near–Earth objects, including 1998 stories of the XF11 asteroid. The report was found newsworthy because “it could be framed as a time–specific disaster event circumscribed and legitimized by quantitative science” [2]. The fact that the original calculations were challenged just a few hours after they were announced, and XF11 posed no danger to Earth, resulted only in journalists adding a few “ifs” and “mights” to their end–of–the–world stories. According to Mellor, asteroids were constructed as a risk by a small group of scientists, and mass media journalists tended to report the quantitative risk assessments of a few scientists as representing scientific consensus, or even fact. While no evidence exists of an asteroid impact ever having harmed a single person, journalistic misapplication of mathematical models and predictions led to reports that a person was as likely to be killed by an asteroid as by a plane crash or terrorist attack. Presenting probabilities generated from models as conclusive evidence is one sort of error, and comparing theoretical with actual events is another — the latter serves to legitimize and personalize the threat. With a risk of such great magnitude, and a public already on edge about Y2K, the story was catnip to journalists, and the majority of space scientists, with happier but far less exciting conclusions to report, found themselves outside the media spotlight.

Unlike an asteroid impact, the consequences of contact with extraterrestrial life can be framed as either a potential benefit or potential risk. While science fiction and popular culture are brimming with portrayals of both extremes, there have been relatively few attempts to quantify the likelihood — and by extension, the risk — of alien life scientifically. Perhaps the most noteworthy exception is the Drake equation.

The Drake equation

Stephen Hawking’s speculation about the intent of alien visitors to the Earth has its roots in what has come to be known as the Drake equation. In 1960, astronomer Frank Drake attempted to estimate the number of extraterrestrial technological civilizations by combining seven key variables. The Drake equation is usually expressed as follows (SETI Institute, 2010):

N = R* • fp • ne • fl • fi • fc • L

N = The number of civilizations in the Milky Way Galaxy whose electromagnetic emissions are detectable.
R* = The rate of formation of stars suitable for the development of intelligent life.
fp = The fraction of those stars with planetary systems.
ne = The number of planets, per solar system, with an environment suitable for life.
fl = The fraction of suitable planets on which life actually appears.
fi = The fraction of life bearing planets on which intelligent life emerges.
fc = The fraction of civilizations that develop a technology that releases detectable signs of their existence into space.
L = The length of time such civilizations release detectable signals into space.

While none of the seven variables can be known with any precision, much research in astrobiology can be applied to the question of determining a realistic range of possible values for R*, fp, ne, and fl. For example, since 1995, close to 900 extrasolar planets have been discovered (see, which may indicate a higher range of values for fp. The remaining variables are more sociological than cosmological, and generally outside the purview of astrobiology or any data–driven science. Depending on the values of each of the variables — and the values of the individual doing the calculation — there may be millions of technologically advanced civilizations spread across the galaxy with whom we might communicate, or we may be the only sender and the only receiver in a single–node network. However, it is important to note that nowhere in the Drake equation is the intent of alien civilizations addressed.

The construction of Stephen Hawking

Rodgers (1992) discusses the “Hawking phenomenon” in the wake of the runaway popularity of A Brief History of Time (Hawking, 1988), and identifies its inviting, accessible language, the authenticity of an author who is a leading scientist as opposed to a science journalist, and the sympathy engendered by “a brilliant mind imprisoned in a paralyzed body” [3] as key factors in the book’s popularity. Rodgers concludes that though many buyers of the book may not have been able to understand it or even finish reading it — Schnabel (2003) refers to it as “probably the most unread book of all time” [4]— those readers who did may have received the unexpected yet attractive message that “science is a human activity ... and that scientists, even of Hawking’s stature, make mistakes” [5]. Conversely, Dunning–Davies (1993), in a rejoinder to Rodgers, writes that Hawking “has been built up in the eyes of the public as the greatest British scientist since Newton” [6], based more on his popularity than his scientific merit. So resonant is the Hawking name that some scientists, Dunning–Davies claims, “have had other papers rejected simply because the end result disagrees with Hawking” [7]. Integrating public opinion into the practice of science, particularly scientific controversies, is a hallmark of what has been termed post–normal science (see, for example, Funtowicz and Ravetz, 1992).

In the intervening years, Hawking’s transformation from scientist to celebrity scientist has only become more entrenched. He has appeared on numerous television shows including Star Trek: The Next Generation, The Simpsons and Red Dwarf, and hosted the anthology series Masters of Science Fiction. With the authority of an accomplished scientist and the media platform of an entertainer, Hawking has become in the eyes of many something close to the personification of modern science.

“Celebrity” scientists who cross into the public domain usually face conspicuous scrutiny from colleagues. While editors and producers serve a gatekeeping function in traditional popular media such as magazines and television, becoming a Web celebrity has essentially no barrier to entry. Porting an acknowledged scientific reputation to the Web environment creates a new type of hybrid authority, where reason and rigor matter less than expressing what large numbers of people find interesting. The compromises inherent in distilling and reporting complex information, compounded by the personal beliefs of the scientist, often serve to exclude diverse and conflicting ideas from public view. In the eyes of the public, the opinions of a noted scientist are often conflated with the consensus of science as a whole, yielding predictable backlash. Carl Sagan, probably the most iconic celebrity astronomer, published hundreds of peer–reviewed scholarly papers in addition to his popular works, yet was regularly denigrated by his colleagues as more of a popularizer and editorializer than a scientist (Poundstone, 1999). Perhaps not coincidentally, Sagan wrote the introduction to A Brief History of Time.

What Hawking said

In April 2010, several hundred scientists and students gathered outside Houston, Texas, for the Astrobiology Science Conference (AbSciCon), a biennial meeting of researchers interested in the question of life elsewhere in the universe. AbSciCon is a highly interdisciplinary conference; most participants come from a range of disciplinary homes, including astronomy, biology, physics, geology, microbiology, hydrology, atmospheric science, computer science and many others, and include representatives from NASA and other national and international scientific organizations. Ironically, just as AbSciCon was taking place, Stephen Hawking began promoting his latest Discovery channel miniseries, Into the Universe with Stephen Hawking. The first episode, “Aliens,” contained the following passages:

“To my mathematical brain, the numbers alone make thinking about aliens perfectly rational. The real challenge is to work out what aliens might actually be like ... We only have to look at ourselves to see how intelligent life might develop into something we wouldn’t want to meet. I imagine they might exist in massive ships, having used up all the resources from their home planet. Such advanced aliens would perhaps become nomads, looking to conquer and colonise whatever planets they can reach. Like us, they would probably have evolved from a species used to exploiting whatever it can. If aliens ever visit us, I think the outcome would be much as when Christopher Columbus first landed in America, which didn’t turn out very well for the Native Americans.”

Media reaction was immediate and widespread. Headlines included “Don’t Talk to Aliens, Warns Stephen Hawking” from the Sunday Times (Leake, 2010), “Hawking: Aliens May Pose Risks to Earth: Astrophysicist Says Extraterrestrials Likely Exist, But Could be Dangerous” from MSNBC (2010), and “Stephen Hawking: Aliens Might Hate Us” from CNET (Matyszczyk, 2010). Recalling Mellor’s (2010) work on asteroids, Hawking’s statement framed extraterrestrial visitation as the same sort of apocalyptic threat. It was given credibility by Hawking’s scientific reputation, amplified by the platform of television and associated Web publicity, and though no specific numbers were offered, the phrase “to my mathematical brain” implied a quantitative calculation, giving the pronouncement even more perceived authority.

Where a potential asteroid collision might be avoided with advanced telescopes and coordinated strategies to destroy or re–route the object, the only practical defense against unfriendly space aliens is to be quiet and hide. The wisdom of broadcasting signals that extraterrestrials might receive and trace back to their point of origin was debated in these and other media accounts, despite the fact that television and radio broadcasts have been emanating from Earth for approximately 75 years, and that only one message intentionally directed at outer space, the Arecibo message in 1974, has ever been sent. What had been interesting if harmless images of Mars rovers scurrying around the red planet digging for fossilized microbes, or the Search for Extraterrestrial Intelligence (SETI) Institute scientists listening for alien signals, now had the potential to be conflated in the public eye with a threat to civilization.

While the impact of a single scientist of Hawking’s stature is considerable, actors at all levels can influence public perception. For example, Haran and Kitzinger (2009), echoing the work of Shapin and Schaffer (1985), discuss the role of “modest witnesses” in the media validation, and subsequent invalidation, of cold fusion. Initial media reports of breakthroughs in cloning and stem cell research portrayed Hwang Woo Suk as the latest incarnation of the archetype of a scientific hero. When the findings were revealed as a hoax, instead of questioning the scientific orthodoxy and media coverage that allowed unconfirmed reports to become so widespread, Haran and Kitzinger report that the trend in the media was to defend science even more strongly, on the grounds that such hoaxes could be so quickly debunked. Whether supported or contested, scientific breakthroughs have always relied on modest witnesses as well as “superstar” scientists, be they researchers, students or other trusted, nominally objective people who vouch for or against the reported results. While Haran and Kitzinger focus on specific scientists and others appearing beside Hwang in photos and video reports, the entire network of scholarly communication and bibliometrics, where aggregated citations from unknown others combine to create a measure of authoritativeness and merit for published research, operates on a depersonalized form of modest witnessing. From a science studies perspective, Collins and Evans (2009) propose a “Periodic Table of Expertises” that acknowledges granular distinctions in tacit knowledge of scientists and lay citizens, and proposes appropriate levels of specificity at which each group can contribute and communicate. In either case, while the specifics of the credentials of each contributing individual may be unknown, when a sufficiently high threshold of associations is reached, some perceived authority is conferred.

Public lack of trust in both science and the media, combined with the ability for individuals to comment and debate alongside most media reports on the Web, has created ripe conditions for people to witness for and against science in the same venues as the science itself is reported. A Web report is no longer a stand–alone article or press release with a single point of authority; increasingly it carries with it a dynamic conversation allowing several, or several thousand, expressions of support or dissent. While a single pseudonymous commenter on the Web carries little or no authority, the collected opinions of many can create a kind of aggregate peer authority (Gazan, 2008) that drives many of the user–generated and user–vetted systems generally described as Web 2.0. Further, people’s online identities often develop reputations of their own within a given system, with their posting histories publicly viewable and posts easily followed. The sentiment analysis method of Web research involves the automatic mining of expressions of opinion from unstructured text (Liu, et al., 2005). While sentiment analysis is an efficient way to harvest general trends from large quantities of text, purely automated strategies restrict output to a representation of positive, negative or neutral sentiment, and function poorly with small amounts of text such as article comments. For more precise and refined analysis, a combination of automated methods with human review and categorization is appropriate (Bermingham and Smeaton, 2009).

The question guiding this study is: How does the speculation of a celebrity scientist affect people’s stated opinions about the risks and rewards of scientific endeavor, specifically the search for life in the universe?



3. Method

The Web is an appropriate venue for scientists and lay individuals to interact, and for researchers to investigate public awareness and opinion (Falchetti, et al., 2007). However, in any environment of incomplete information, both intellectual and affective factors come into play (Powell, et al., 2007; Nahl and Bilal, 2007), necessitating qualitative as well as quantitative analysis.

The first phase of this study used naturalistic observation (Lincoln and Guba, 1985; Mann and Stewart, 2000) and sentiment analysis of several popular Web communities where Stephen Hawking’s speculation on alien intent was reported, analyzed and discussed, with the goal of determining an initial set of categories of public reaction and opinion, to analyze the impact of Hawking’s statement. All the sites chosen are well established news sources and hubs of discussion, each ranking in the top several hundred or several thousand in terms of Web traffic, have a news focus as opposed to science fiction or entertainment, and allow user comments on posted stories, though only if the poster is registered with the site, to encourage more serious contributions and help minimize spam or nonsense. All comments were reviewed inductively; an initial coding pass sought to identify broad patterns in the data, with a second pass to refine categories and to integrate diverse expressions of the same basic sentiment.

User–generated content on the Web is almost always a moving target. Though some sites close comments after a time, others allow people to post reactions indefinitely. Some comments are removed by moderators for violations of site policies, or removed by the posters themselves. Overall, 2,113 comments were analyzed across three sites, and coded for category membership. Of these, 674 were discarded from the sample as their intent was clearly off–topic or unclear, though every effort was made to accommodate and translate indirect forms of expression, yielding an n of 1,439. Comments varied widely in length and content, and single comments could be coded as members of multiple categories. While the comment threads attached to the main articles on each site were initially reviewed for comments, some sites distribute discussion about the same topic across several threads; in these cases, multiple pages were analyzed. Comments were mined from the following three sites:

“Stephen Hawking Takes a Hard Line on Aliens; The Eminent Scientist Warns that if There is Life Out There, We Probably Don’t Want it Messing with Us.” Posted 26 April 2010, 267 comments (Hickman, 2010)

The online version of the Guardian and the Observer, contains most material found in the print newspapers, with online–only content as well. According to (, as of May 2013 the site’s traffic rank is number 204 in the world, and number 18 in the U.K. While users must register with the site in order to comment and user profiles are visible, including a history of past comments and a “clippings” section where users can store links to past Guardian content. Ratings are restricted to recommendations of specific comments and do not accumulate to a user’s overall profile.

Huffington Post

“Stephen Hawking: Humans Should Fear Aliens.” Posted 25 April 2010, 3,994 comments (Huffington Post, 2010)

The Huffington Post is an online newspaper and social hub that features the work of reporters and bloggers, and encourages user commentary and discussion. Its traffic rank is number 97 in the world, and number 20 in the U.S. according to a May 2013 query. Many reports are a combination of brief commentary and links to other sources to launch conversation, and thus do not carry a byline. Users must register to post comments, and their histories are viewable to all. They earn levels, badges and titles for their comments and contributions, which are appended to every comment they post, thus accumulating a public and persistent form of social capital on the site. A thought–provoking, funny or otherwise interesting comment often draws a reply “Fanned!,” meaning the person replying deems the comment author’s content worthy of triggering a selective notification for all future posts. An inspection of the sample for this study revealed many users with in excess of 100 fans each, hence a relatively large percentage of posts are social and self–referential, and not directly on point.

Discover Magazine

“In Which I Disagree With Stephen Hawking.” Posted 26 April 2010, 160 comments (Plait, 2010)

Discover Magazine is a science news magazine with a longtime Web presence, and focuses specifically on space–based news and information. It ranks number 18,545 in global traffic and number 6,843 in the U.S. according to a May 2013 search, but its specific focus on speculation and extrapolation about current scientific knowledge makes it a uniquely specialized resource for this study. Relevant comments were found on several pages, but the primary data source is in response to a blog post, the title of which communicates an ironic self–reprimand for the author having the audacity to critique Stephen Hawking. The Discover Magazine site requires registration and login to comment, but user profiles and past contributions are not visible, and no rating or recommending of either comments or users is possible.

Naturalistic Web research carries a common set of caveats. Even the most popular sites are accessed by a very small percentage of the population, and smaller still is the fraction who post comments. Of those who do, there is no way to verify that what is posted reflects their actual opinion. Unless access to the database backend is available, it is impossible to tell whether one person may be posting under multiple account names, or whether some content has been removed by moderators. However, analyzing sufficiently large numbers of individually questionable data can suggest potentially interesting aggregate trends. As with all inductive methods, this data could be coded along many alternative dimensions, with corresponding differences in categorical interpretations.



4. Results and discussion

The results of the data analysis (Table 1) suggest that on the sites studied, public reaction to Hawking’s statements could be clustered into thirteen major categories, providing an overall sense of the posters’ sentiments toward and understanding of astrobiology. Examples from each are presented as found, with spelling and grammatical errors. The source of quoted comments is indicated by (G) for, (H) for Huffington Post, and (D) for Discover Magazine. It is important to emphasize that though a comment is presented in one category, it may also have been coded in one or more others. Of the 1,439 raw comments coded (H 1,090, G 211, D 138), a total of 578 multiple codes were assigned.


Table 1: Categories and coding instances from Hawking–related comment threads on three news sites.
Sources: G:; H: Huffington Post; D: Discover Magazine.
Agreement based on Hawking’s authority2320826257
Agreement based on logic or science1310719139
Undifferentiated agreement1449265
Disagreement based on Hawking’s domain of expertise299415138
Disagreement based on logic or science8829051429
Undifferentiated disagreement198416119
Science fiction5915025234
Media hype30898127
Forces transcending science1450569
Alternative explanations26341070
The answer is unknowable336214109


Agreement based on Hawking’s authority. The most frequently observed category of agreement was “the hammer of Hawking,” where posters indicated that Hawking’s interpretations were correct, or at least more plausible than others, simply or primarily because they came from Stephen Hawking. These were found almost half the time in conversations among commenters, where one poster tended to invoke Hawking to squash another poster’s dissenting opinion.

G “I agree with the brainy man. Let’s not go drawing attention to ourselves, shall we?”

H “Stephen Hawking, in my humble opinion, is the brightest man we have on this planet. I’d take what he has to offer over ANY other scientist out there.”

D “Hawking is a smart bloke renowned for his intellect — so, yes, I think his views carry some weight on a lot of things incl. this issue.”

Agreement based on logic or science. The second most common expression of general agreement included a more direct appeal to science; in other words, that according to the person commenting, Hawking’s stance makes sense logically and/or scientifically.

G “I think Hawking’s point is rather: we don’t have the technology to visit them, so they are likely to be considerably more advanced than we were. So the analogy with native americans is likely to be an apt one.”

G “From a simple look at the odds, it’s obvious Professor Hawkins is correct ...”

H “It doesn’t take a genius to figure out Hawkings is probably right. Aliens who could and would travel across unimaginable distance to reach us probably wouldn’t do it solely out of curiosity and with nothing but egalitarian goodwill toward an alien species and an alien world. Humans would either represent a resource to be exploited, or an inconvenience to be eliminated.”

D “So I would tend to agree with Mr. Hawking, who seems awfully smart, that since the most successful life forms we have ever seen are those that kill off their competition, it is not unreasonable to assume that life forms successful enough to have mastered interstellar travel might also be quite used to killing off life forms that competed with them for resources. I don’t think the Columbus analogy is far off.”

Undifferentiated agreement. Some statements of agreement defied categorization, as they appealed to neither Hawking’s authority as a scientist, nor to the merits of his claim. The following example was initially coded as an expression of fear, then re–categorized as an undifferentiated agreement.

G “Yes he is right. They will enslave and eat us. We would deserve it too!”

Disagreement based on domain of expertise. While roughly 36 percent of commenters disagreed with Hawking overall, a frequently observed rationale was the commenter’s perception that Hawking is outside of his area of scientific expertise.

G “... why are no social scientists considered in this question? I appreciate things to do with biology, the nature of the planets are essentially in the realm of scientists, and that these would be enormously influential in shaping any alien society, but surely to only focus on that is to get into very deterministic territory.”

D “Hawking’s views on this are about as relevant as Pauling’s views on vitamin C.”

G “I can see Hawking’s point but he’s a scientist and not a historian, a sociologist or an anthropologist.”

G “In such a case as this he is, essentially, as ignorant as the rest of us. so while we can use his opinion for debate he’s really just pissing in the wind and I’m sure he knows it.”

Disagreement based on logic or science. The most commonly observed reactions across all categories and on each of the three sites were statements indicating that the poster felt Hawking’s argument failed on logical or scientific grounds.

D “I am highly skeptical of Hawking’s claim that aliens exist, like what is shown on the Discovery Channel. Like anyone else who claims they believe aliens exist, I ask, ‘Where’s the evidence?’ In this case, there is none ...”

H “Hawking should know better. Distances alone guarantee that there will never be physical contact unless the existing laws of physics are upended.”

G “Is he serious? You know there might just be some resource rich planets a little closer to wherever they call home, mostly without pesky life forms to get rid of.”

D “Let’s not make the mistake of using our own behavior as the template for others.”

Undifferentiated disagreement. Interestingly, many statements of undifferentiated disagreement included some acknowledgement of Hawking’s authority.

D “Such silliness from Hawking. He’s wrong, even if he is still brilliant.”

H “I would normally not venture to disagree with Mr. Hawking but here his assertion is laughable.”

H “The only reason this interview was published is because it is Steven Hawking. If this statement had been made by any politician we would be questioning their mental stability. We need to evaluate a statement on its own merit, versus on who is making the statement.”

Fear. Comments expressing direct worry about the implications of alien malevolence were generally in agreement with Hawking’s comments, and could be interpreted as a sample of the public’s understanding of the risks of the search for life in the universe. Humorous expressions of fear were not coded in this category, but extensions of Hawking’s comments, such as worry about alien microbes, were included.

G “Cripes! Scary stuff ...”

H “We won’t know until we meet them, which is a scary thought if they turn out to be like our sixteenth century brethren, and we’re the technologically primitive natives.”

D “Civilizations are ‘visible’ only for a short period of time before they get all paranoid and do as Hawking suggest: avoid contact, stay as low as possible.”

H “Scary is when only a few or a limited percentage of the humankind dies. When the whole of it is under threat of being wiped out in a single strike ... We really lack vocabulary for events of that magnitude.”

G “... no–one is taking this seriously, if Stephen Hawkins says something then we should listen ...”

Science fiction. A somewhat unexpected finding is the large number of posters who referenced science fiction, movies, books and other aspects of popular culture. While most references were invoked for comedic purposes, they were often used to denigrate Hawking’s statement by likening it to science fiction.

H “What the heck is this guy talking about? Jodie Foster met aliens, and they were nice.” [reference to Contact]

H “Did Hawking write the script to Independence Day?”

G “what do you mean is Hawking right? all he did was regurgitate the plot–lines to a hand full of very average Hollywood films”

G “I for one welcome our new overlords.” [reference to The Simpsons]

Media hype. Whether agreeing, disagreeing or expressing no opinion, many individuals blamed the media, for presenting speculation as fact or sensationalizing Hawking’s comments. Responses coded for media hype included those claiming Hawking was being used by the media, or that he was a knowing participant.

H “I think Hawking is ... well, hawking this Discovery TV show he’s done ... It’s embarrassing that one of the greatest minds of the 20th century is turning into a ridiculous schill in the 21st. He’s doing it for the money, honey.”

H “being a mathematical genius, which Dr Hawking certainly is, doesnt really help here. Extraterrestrial biology/psychology has nothing at all to do with the kind of science H is justly famous for. Blame DISCOVERY. He’s ‘a scientist‘, so he must ‘know stuff’ about everything.”

H “The headline is misleading ... Hawking speculated a number of different scenarios for alien existence. This is just one, and he never promoted ‘fear’ or used that word.”

H “... no one ever got a headline in the news saying, ‘Aliens have not landed, and we have no evidence that they exist outside of an equation that we invented ...’”

D “... how much of his ideas and thoughts wound up on the cutting room floor, as it were, after editing by the networks ... Even Stephen Hawking would have to bend some in order to get his ideas out to the public.”

Risk/reward. A significant number of posts focused specifically on perceived probabilities and risks of alien visitation, rather than adopting a particular opinion.

D “Hawking is right to be cautious. Some may be nice, some nasty, and their range of motivations / impacts will probably be vast.”

H “We just don’t know, and can’t know, in advance, but we have no basis to assume that interstellar travelers would respect human life or human civilization ... perhaps they would, however, its very dangerous to assume such a thing.”

Forces transcending science. Still broader reactions included those portraying Hawking as a pawn of larger social or physiological forces.

H “In some ways, Mr. Hawking’s alien conjectures could be viewed as one of many attempts by prominent scientists to address matters formerly the purview of religion ... Instead of a preacher putting the fear of God into a tremulous flock of congregants, we have a secular priest putting the fear of aliens in us.”

H “What Stephen fails to acknowledge, is that not every being in the universe thinks with a eurocentric ideology; where materialism, self, and conquering is the only purpose.”

H “Who knew that Hawking was such a closed–minded pessimist, capable of stereotyping hypothetical aliens with one broad stroke? Who suspected his view would be so stereotypically male?”

G “Elephant in the room, but might Hawking be losing it a bit? Not a lot, but just a touch? I mean, he’s getting on a bit, he’s not exactly a picture of health, so I wonder if ... I just wonder if. He knows his theoretical physics, no doubt, so for him to start banging on about aliens visiting earth seems a bit odd. He’s entitled to believe whatever he likes, but I would ordinarily expect more rigour from him.”

Alternative explanations. A small but strident group of posters did not directly engage with Hawking or his statements, but did propose alternative explanations or questioned Hawking’s premises.

D “I wonder about another possibility, that technology so transforms culture that the notions of ‘travel’ and ‘colonization’ are either wildly transformed or no longer relevant.”

D “Or it could be that we are alone in the whole universe. Maybe unlikely, but not impossible ...”

H “Some of you may want to laugh at this and please feel free, I don’t care. They are already here. 1980 in the UK I had an encounter with a massive craft, almost the size of a football field, hovering about 10 feet above the ground ... For me there is no ‘what if’ question.”

The answer is unknowable. Perhaps the most objectively accurate reaction is that Hawking’s statement was nothing more than one person’s guess.

H “This is science fiction done by a theoretician, Hawking. Its not the word delivered from God on high. There are many interesting theories about aliens but they are all just wild speculation. Even if they come out of the mouths of scientists.”

G “Is Stephen Hawking right about aliens? Surely the only sane answer to that question is: Who the fuck knows?”



5. Conclusion

The results of this study suggest that Stephen Hawking’s authority as an eminent physicist was interpreted by 23 percent of the “modest Web witnesses” studied as a scientifically credible warning, framing extraterrestrial visitors as a planetary threat. Roughly 36 percent explicitly disagreed, but on no greater evidence or authority than their own opinion or claimed scientific understanding. Just as in the academic arena, Hawking’s name was sometimes used as a weapon in interactions to squash dissenting opinions. In fact, no one knows about the intent of aliens, and perhaps the most surprising result of this study is how few individuals claimed not to know.

Future research might undertake a more refined analysis of user interactions on Web discussion sites, to understand how posters with varying amounts of social capital as expressed by badges, titles and other signifiers of site–specific credibility debate and cite one other’s authority, and possibly influence the expressed opinions of others. The next steps of this study will attempt to determine whether Hawking’s statements changed people’s opinions, and whether or not people believe Hawking’s opinion represents the consensus of science as a whole.

Stephen Hawking’s influence on popular culture shows no sign of abating. In an April 2013 lecture at the California Institute of Technology (, Hawking claimed that according to our current understanding of physics, the Big Bang could have happened spontaneously, making God unnecessary. Hawking came to a similar conclusion in his recent New York Times bestseller The Grand Design (Hawking and Mlodinow, 2010). In the trailer for the science fiction movie Skyline, released in November 2010, retired newscaster Dan Rather delivers a somber news report quoting Stephen Hawking’s warning about colonization not turning out well for Native Americans, just as alien ships arrive and vacuum up hundreds of screaming people into their vessels. When the authority of scientists and journalists is hybridized with mass media entertainment, astrobiologists peering into telescopes and computer screens can scarcely be expected to compete for a place in the public imagination. Ironically, the astrobiology community may stand to benefit from public fear of aliens. But through outreach and analysis of public opinion, misconceptions can be identified, science fiction and opinion can be embraced yet kept in their place, and the sublime question of life in the universe can be addressed. End of article


About the author

Rich Gazan is Associate Professor in the Department of Information & Computer Sciences at the University of Hawaii.
E–mail: gazan [at] hawaii [dot] edu



This material is based upon work supported by the National Aeronautics and Space Administration through the NASA Astrobiology Institute under Cooperative Agreement No. NNA08DA77A issued through the Office of Space Science. I would like to thank Stephen Freeland, Leah Rubio and the anonymous reviewers for their contributions to this work.



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Editorial history

Received 31 May 2011; revised 2 May 2013; accepted 8 May 2013.

Copyright © 2013, First Monday.
Copyright © 2013, Rich Gazan.

The hammer of Hawking: The impact of celebrity scientists, the intent of extraterrestrials and the public perception of astrobiology
by Rich Gazan.
First Monday, Volume 18, Number 6 - 3 June 2013

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