Dyson Sphere

Compared to the Cocconi and Morrison’s proposal to search for radio signals in the nearby stars. Dyson (1960) pointed out it was also useful to look at infrared signals at 10 microns radiated by his hypothesized Dyson sphere. He argued much more advanced civilizations would have built thin shells around their host stars to more efficiently harvest the energy of the host star.

He argued the Malthusian pressure would drive some of the advanced civilizations to build such a sphere to catch up with the exponential population growth. Additionally, he also argued that the such a sphere would have similar orbit size as the Earth and same temperature as well so that we could possibly detect it at the 10 microns which was also transparent to the Earth atmosphere.

I do not really understand how he concluded that the temperature of the sphere would be at the same temperature as the Earth. Would not the energy harvesting efficiency be much higher if the sphere was radiating at a much lower effective temperature. It seems to me that his conclusion about the temperature of the sphere came from our understanding of the Earth and it was 10 microns which was also transparent to the Earth atmosphere made him draw the conclusion that we should observe at 10 microns.

In the later reply letter, he clarified the idea of Dyson sphere to not being a solid sphere which was physically impossible to build but a swarm of objects traveling on independent orbits around their host star. He also admitted whether the alien civilizations obeyed the Malthusian principle or not was a question of taste. Finally, he argued that even if we did not find any aliens, the search for intense infrared signals could help us identify interesting astronomical objects.

Dyson and the Beginnings of Artifact SETI

In Dyson (1960), the beginnings of a new type of SETI is proposed that has significantly fewer behavioral and technological assumptions about ETI (Wright 2014). If ETI does exist and use a large amount of energy, they will likely be utilizing starlight as an easily accessible energy source and be indirectly converting it into IR radiation. The search for this IR radiation is proposed to complement the existing searches for communication.

Dyson argues that if exponential population and technology growth is sustained for a couple millennia, a civilization could use on the order of a Jupiter mass’s worth of material to construct a spherical shell around the Sun (using only 800 years worth of solar energy!). This is followed by the bold statement that “One should expect that, within a few thousand years of its entering the stage of industrial development, any intelligent species should be found occupying an artificial biosphere which completely surrounds its parent star.” Finally, he notes that the thermal emission of these shells will be in the IR range and that ground telescopes will be able to detect them through the atmosphere.

A popular idea that resulted from this paper was that of a Dyson sphere, a hypothetical megastructure that completely encloses a host star, capturing all of its energy. It is sometimes postulated that the sphere is not only used to capture energy, but to also serve as a space for habitation, where life can live on the inner surface of the sphere. If one was constructed with a radius of 1 AU around out Sun, there would be more livable space than half a billion Earths! There are several problems with this implementation, namely, there is no material we know of that could withstand thepressure imposed by the star’s gravity. Additionally, there would be no effective gravity imparted by the shell on anything in its interior, so there would be nothing holding anything to the interior surface and the shell could drift into the star over time.

The Dyson Sphere has remained a prevalent idea in popular culture to this day, with appearances in many forms of science fiction media (including the television show Star Trek: The Next Generation and the grand strategy videogame Stellaris)

In Stellaris, you can spend an inordinate amount of resources constructing this mega structure. Realistically, it turns all rocky planets and moons in the system into frozen or barren worlds. Unrealistically, the amount of energy provided does not vary between different star types. Tsk tsk developers.

 

3 Types, 3 Questions

This week, I wanted to talk about Kardashev (1964) because I naturally started doing a lot of follow-up as I read. The famous idea that was first proposed in this paper was the classification of civilizations by the amount of energy they consume, as summarized below:

Type I: Earth-level, consuming 4 * 10^19 erg/s

Type II: Full-star usage (a la Dyson spheres), consuming 4 * 10^33 erg/s

Type III: Full-galaxy usage, consuming 4 * 10^44 erg/s

I had three questions that popped up over the course of reading the paper.

  1. Has the definition of Type I always been the same over time?
  2. Did we keep up with Kardashev’s energy growth rate predictions?
  3. Whatever became of CTA-21 and CTA-102?

I’ll tackle these one at a time.

  1. In my memory, when I’ve heard about the Kardashev scale before, humanity was said to be at a Kardashev 0.7 or so, which is a pretty long way from a Kardashev I (because the scale is not linear). The argument that I read (I believe in the book Physics of the Impossible by Michio Kaku*) is that a Kardashev I civilization uses an amount of energy equal to the amount of starlight falling on the planet’s surface. A quick glance at the Wikipedia page confirms that interpretation. But, as I mentioned above, Kardashev defined it as being the amount of power that Earth was using in 1964, at the time the paper was written. So when did the flip in definition happen? Turns out this shift was the fault of the ever-present Carl Sagan. His standardization of the scale with a logarithmic power formula allows values other than I, II, and III and allows a more generalizable formulation (versus Kardavshev’s Earth-centric standards). It’s amazing to me that a redefinition happening a decade after the original paper has caught hold so strongly.
  2. Since it has been over 50 years since this paper was written, I was curious to see if we had kept up to Kardashev’s proposed growth rate of 3-4% a year, starting at 4 * 10^19 erg/s. After a long 10 minutes of trying to figure out why my simple exponential growth rate equations were wrong (ergs/second not ergs/year, past-Me), I got an answer of ~6.5 * 10^27 to ~1.3 * 10^28 erg using his values (using 3% and 4% growth respectively). The actual current value is 3.9 * 10^27 erg, so while Kardashev’s predictions were optimistic by a factor of 2-3, they weren’t really that far off. That’s honestly pretty impressive, at least to me (perhaps an economist would say that this is an easy problem, but it isn’t quite intuitive to me). Will it continue at this rate, or will we level off in some logistic-like function? That’s the question, isn’t it? But at least so far, we’re on track with Kardashev’s prediction.
  3. After some research on CTA-21 and CTA-102, it looks like (predictably) they were both false alarms. CTA-102, according to a quick Wikipedia, is identified as a very-variable quasar with extremely luminous “blazar states”. This is a great example of how objects of interest to SETI (at least in the context of artifact SETI) are going to invariably be interesting to the rest of astronomy, and should be valued for that reason. Meanwhile, both objects had an entire article in the NYT written on them by none other than Isaac Asimov. A quick scan on Google Scholar suggests that it too is just a quasar, though a less extreme example than CTA-102.

*This book was my “eureka” moment about wanting to be a physicist/astronomer. I picked it up on a whim when my seventh grade book club got to go to the local book store for a mini-field trip. After finishing it, I decided that I wanted to go into physics, and I haven’t looked back since.

Our Aliens are Just Like Us (and this could be a problem)

Michael Oman-Reagan is an anthropology student at Memorial University of Newfoundland, and runs a column on sapiens.org called Wanderers, dedicated to exploring “anthropological insights from our encounters with outer space as we study the origins of life in the universe, search for extraterrestrial intelligence, prepare to send humans to Mars, and imagine travelling to distant stars.” In an article from February last year (2017), Oman-Reagan discusses many possible differences that alien species could have compared to the human race. He goes into detail about specific things that we find hospitable, and many things that we subconsciously do that might be perceived as amusing or hostile (or beautiful or ugly).

Oman-Reagan concludes his article by saying that any hosting of aliens would require interdisciplinary tools as well as “anthropological insights about intercultural contact and our human tendency to naturalize and then universalize culturally specific behavior and beliefs.”

Although anyone who thinks about it will come to the conclusion that alien species will probably be unlike human, many people don’t bother to consider *how* unlike us the species could be. I think this is an excellent point! Even books/shows/films known for their variety of species keep alien cultures to be fairly mild and still akin to our own. I’ll list some examples of species below that are, at first glance, quite unlike our own. These species end up having one or two things different from us, but it is possible there exists a species that is completely opposite from us; not only would they look different, communicate differently, sense things differently, but they might enjoy everything we despise and be offended by the things we enjoy. Oman-Reagan points out that certain habits of ours are (in our culture) subconscious, that we do not do them intentionally to be proper or rude or kind or curious, and that many would not even think these things *could* have an impact on anyone. A good example is that we blink. We need to blink, in fact it is so hard *not* to blink that we have contests to see who can go the longest without giving in. If blinking is not required for a species as it is for ours, then maybe such an action could be seen as “beautiful, hilarious, offensive, or threatening.”

I personally had never thought of this! I have read and watched sci-fi for nearly all of my life, and yet when I think of aliens, I think of creatures that are actually quite similar to us (now that Oman-Reagan has pointed out how completely different they could be). Were I to interact with or host an alien species, I would not think about possibly offending them, and certainly not through actions we consider hospitable or through our anatomy or through subconscious actions. In my mind, anything that we dismiss as “only human” would also be dismissed by other species, but that isn’t necessarily true at all!

It seems to me that we cannot think of cultures that are far from our own (all of the below species blink!). We can create species in science fiction that look and act differently from our own, but we never stray too far from humankind. Given the lack of diversity in science-fiction species, it makes complete sense that Oman-Reagan would publish this article! If we do ever interact with alien species, and are able to communicate with and understand them within reasonable time periods, it will be quite important to keep in mind how vastly different from us they could be. Although it is possible, it is not guaranteed that they will be similar to the species in our sci-fi.

As promised, here are some examples of humanoid*** alien species from popular literature (I feel this is alright since Oman-Reagon included an alien species image in his article.) Buckle up, because things are about to get nerdy in here!

The Borg are a species of cyborgs from Star Trek. Although they technically are many species since they steal infants from other planets, give them implants, and make them part of the Hive, I’m going to consider them their own species for now. The Borg operate as one, linked by a hive mind. They aim to achieve “perfection” by assimilating species, technology, and knowledge. Their only requirement is energy, which they receive on their ships in small, personal alcoves. As portrayed in the show, the Borg are considered dangerous and ruthless. They are technologically advanced and seek out knowledge and species to assimilate. Although they seem quite different from humans, they aren’t super different. I would argue they are similar, just lacking culture. There’s no way to amuse or offend one of the Borg drones, as they value only knowledge and perfection. Without culture, they are simply beings following a single ambition.

More Star Trek! A reoccurring race in New Generation and Voyager is the Q. The Q are immortal, intelligent, and have the ability to control space, time, matter, and energy. They evolved over centuries to what they consider to be the “state of ultimate purity.” They are apparently absurdly intelligent. This trait, matched with they abilities, makes them quite apathetic to basically everything. One specific Q, named Q, spends episodes messing with the crew as a form of entertainment since the species had already accomplished everything that could be accomplished. Although god-like, Q himself is quite similar to humans. He can be entertained and annoyed, in ways similar to humans. He can also be petty and annoying himself.

The Silurians are a reptile-humanoid species in Doctor Who. While they look quite different from humans, they still have the general humanoid shape, size, and mannerisms. Although they are telepathically linked to one another, they are capable of speech and use it when communicating with other species out of kindness. They are generally peaceful, and in fact are forbidden from warfare except in defense. They believe in keeping their species pure, and follow a religion similar in kind to many religions we have. They value art, sports, and games, but at what level is not really discussed. They even have poetry composed of optical illusions! The Silurians are, in fact, quite similar in culture and anatomy to humans.

The Trees of Cheem are an intelligent race of humanoid trees. They do not understand technology and give clippings of their relatives as gifts. They all have retractable vines on their arms, but showing these vines is considered highly inappropriate. The species, although wealthy, is wise and compassionate. The Trees can feel any pain from vegetation on their planet, and usually keep it quite protected. Although they don’t have technology and say they do not understand it, they are able to use it. They are also quite clever and able to successfully judge the character of people. This species, an evolved form of tree from Earth, is also quite similar to humans! Their mannerisms are similar, and aside from giving away body parts and being flammable, they seem near identical in culture and personality to many humans.

The Ood are another species from Doctor Who. They are unable to speak vocally, communicating telepathically. They are humanoid with tentacles on their face (for eating) and the color of their eyes indicates the level of telepathy currently used. They have very long lifespans. They technically have three brains, one in their head, one they hold in their hands that is connected to their face, and a large communal brain that hosts the hive mind. They are a gentle and harmless species, and are generally considered less advanced than humans. They have a leader, and they sing to portray their emotions. When they are enslaved, they are in pain and quite sad. When they are freed, they are filled with joy.

Again, I would argue that these alien species, although seemingly different from each other and from humans themselves, are quite like us! They have communication, wealth, ambitions. Many of them can be pleased, offended, angered, and amused. In making alien species, it seems that levels of intelligence, technological dependence, and emotional range are simply plucked out of a hat and put into something (usually humanoid) and proclaimed alien. However, all of the technologies and intelligence and emotions are those imagined (or used) by humans, in ways that humans would or do use them, so even the species in science-fiction are quite similar to humans. Since most (maybe all?) of us are exposed to the idea of alien species through sci-fi, my guess is that we all have a similar idea to what aliens will be like, and although we will consider them to be different, we would not consider the possibility that they could be as vastly different as suggested in Oman-Reagan’s article.

 

***I only included humanoid species in this list because, in popular culture, non-humanoid species are 80% of the time just evil and trying to kill humans, 15% of the time pets or pests, 5% of the time alien-looking with exact human personalities and/or cultures.

 

Reaction to Oman-Reagan (2016)

In this popular science article on meta-SETI, Oman-Reagan voices his concern regarding how our physical presentation to an alien intelligence may come across as offensive in ways that we cannot yet imagine. This is referring to an actual physical encounter between humans and ET who come to visit us (though technically it also applies to cases of us visiting them, but our technology precludes this option presently.) Fanciful as it may sound, he does raise concerns that we perhaps have not up until now considered if such an occurrence were to take place. The problem is that, although we may attempt to take every precaution to present a benevolent outward persona, we are limited by our fundamental biology and hence may inadvertently trigger a negative response from the visitors. To illustrate this point, Oman-Reagan brings up scenarios where they view just our gaze or gaseous respirations as acts of aggression, even though they are critical aspects of our biology. There is even a possibility where the perception of time is different between them and us. The metabolism or rate of life of their species may be such that many of their generations will pass for a single human’s or vice versa. This complicates matters of communication between the “slow” and “fast” race. Alternatively, their social awareness may prohibit or require certain modes of behavior which we do not understand, as pointed out by Oman-Reagan. These differences in cultural mores compounded with biological evolution histories dramatically complicate the possibility for a positive first interaction.

This article reminded me of the situation presented in the recent first contact film “Arrival,” where the minds of the aliens operate significantly differently from ours. Warning: film spoilers ahead! Their perception of time is distinct from ours because their language allows them to convey complex ideas simultaneously. This idea is an extrapolation of the Sapir-Whorf hypothesis of anthropology, the idea that one’s perception of reality stems from the grammatical structure and vocabulary of their language, to the aliens. For example, if a people had no word for the color green, then the hypothesis suggests that would have no ability to conceptulize or discuss the idea of green, and thus perhaps may not even perceive it in nature. This is probably untrue in the case of humans however, since we all share the same wavelength coverage and responsiveness to pigments in the ocular cones and rods. Therefore each human has the opportunity to at least perceive green (excluding color-blindedness) regardless of whether or not there exists a word for green in their particular language. In the case of the heptapods of Arrival, their understanding of time is non-linear and enabled by their circular and atemporal representation of information. While this is a different kind of temporal distinction than what is talked about in this article, it does show how biological differences in cognition may adversely affect the first encounter.

Direct Dark Matter detection is NOT analogous to SETI

In this post I seek to address and contradict the Appendix of Wright and Oman-Reagan 2017. I shall not delve into the main contents of the paper, which I wholeheartedly agree with. Before delving into criticism of the analogy stated in the Appendix, I must say that I do agree with the basic premise of the argument. Just not the example used.

Dark Matter  was first evidenced by Fritz Zwicky (1898-1974) (yes the same one who shot through a rifle along the telescope line of sight to clear the atmosphere) in the 1930s. Initially believed by no one, he used this hitherto unknown form of matter to explain the velocity dispersion of the galaxies in the Coma Berenices cluster. Similar results were then found in the Virgo cluster.  A hypothesis that was not accepted till much later, when in the 70s  Vera Rubin (1928 – 2016) and Kent Ford (1931 – ) studied the rotation curve for Andromeda to find an anomaly in the velocity distribution as a function of distance from the center.


Fritz Zwicky explaining dunkle Materie ?

 

Evidence for Dark Matter has also been found in the power spectrum of the Cosmic Microwave Background radiation (CMB). Further, any discussion regarding the discovery of dark matter is incomplete without a reference (albeit passing) to the Bullet Cluster (below).

 

Dark Matter: From shooting bullets, to the bullet cluster. Credit: Clowe 2006

Even though direct detection of the dark matter particles (WIMP, MaCHOs, Axions)  still eludes us, there is substantial evidence which supports the existence of dark matter. Therefore I feel it is unfair to call direct dark matter detection – a speculative field. The exact nature of the dark matter particle remains uncertain, however its existence cannot be questioned.

Extraterrestrial intelligence, on the other hand is a concept until proven otherwise. Despite the doltish nature of anthropocentric arguments against SETI, and my personal distaste for them, till we do not find some evidence for extraterrestrial intelligence we cannot be sure of their existence. There is no observational evidence which supports its existence apart from philosophy, motivated arguments and calculations. As Sagan said “ the only significant test of the existence of extraterrestrial intelligence is an experimental one. No a priori arguments on this subject can be compelling or should be used as a substitute for an observational program.”

For dark matter the evidence already exists, incontrovertible at so. Considering that the search for dark matter particles (direct dark matter search) has a strong theoretical backing, the similitudes for dark matter detection are more with the Higgs Boson or Gravitational Waves than anything else.

As is mentioned in the last paragraph of the Appendix, the analogy is very much an imperfect one. That being said, it cannot be denied that the giggle factor, is very much an affliction for SETI.

However,  we are not the Tralfamadorians from Kurt Vonnegut’s novels, who can see in 4 dimensions; hence being privy to the future as well as of the past. Being as we are without their foresight (hindsight?), we must keep looking till we either find extraterrestrial intelligence or indubitable evidence of the otherwise (however you prove a negative); and so it goes.

Addendum 31st January 2018:

There are certain points which I should have explained better:

  1. The existence of Dark Matter has been proved beyond doubt. The fact that it consists of dark matter particles (or those which can interact with particles from the standard model) has not. It is not 100 % certain. I do not think this is a good analogy with SETI because our existence does not necessarily imply that there DO exist other space faring civilizations. We can only say with 100 % certainty that life CAN exist elsewhere, not that it DOES. Therefore we are searching elsewhere trying to prove the anthropocentric principle wrong.  The fact that dark matter exists, already changes the playing field and erases the similarity to SETI.
  2. Search for the dark matter particle is based on more than just guesses. I believe here an apt comparison to differentiate between the two concepts is to Schelling points in SETI. In SETI, the phase space of possibilities is essentially infinite, however using cultural, biological and physical arguments we make certain assumptions to make the search doable. These arguments are strongly motivated by an anthropocentric bias, but it gives a place to start from.  For Dark Matter particles, these searches are not based on assumptions. There are different branches of theoretical frameworks which match observational evidences and predict different kinds of particle (WIMP, Axions, Supersymmetry etc. ) to fulfill the role of this elusive piece in the puzzle.
  3. The fact that the Standard Model does not include the Dark Matter particle is not a shortcoming of the particle itself, but one of the possible flaws with the Standard Model. Be as it may the most comprehensive theory we have, it has many inconsistencies and things that it cannot explain. Therefore given further research and work on the theoretical aspect, it is possible (albeit not certain) that the Model grows to encompass and address these flaws (supersymmetry , hierarchy problem, neutrino mass, etc.). No theory can ever claim with certainty that ETI exists.

Hosting Aliens: Xenomorph or ET?

The word host has many connotations. In the general context, it refers to an individual who invites guests to a welcoming event, typically as a sign of goodwill and camaraderie. In the biological world, a host is an organism that harbors another organism. Oman-Reagan, in a recent article, speculates what extraterrestrial hospitality would entail. The forms of extraterrestrial intelligence he conjures are fairly benign. He starts with a human example of horrible hospitality: a small enclosure with the bare necessities of oxygen and intravenous nutrients. While perhaps extreme, it brings focus to what properties make a good host. He makes the point that if communicating across cultures for humans is difficult, communicating across species would be worse. Is a good host someone who provides your necessities, however minimal those may be, or is it someone who does this while adapting to a guest’s preferences?

Figure 1: Behold, E.T. the Extra-Terrestrial! Seen here wearing human attire so as to fit in. E.T. is largely benign and may be one of the lifeforms amenable to the treatment presented by Oman-Reagan. Source: “E.T. the Extra-Terrestrial“, Universal Pictures

Oman-Reagan goes on to provide examples of the quirks aliens may show, albeit these largely drawn on human experiences. He states “[m]aybe [a guest] only feel comfortable when accompanied by a companion of another species, but instead of a dog or cat it’s something vastly different, like a mollusk that emits clouds of fragrant, multicolored gas on specific cycles” to show extraterrestrial intelligence with human traits in an otherwise alien situation. Other speculations include the impropriety of eating with others and the use of psychedelic drugs. Oman-Reagan argues that the immense differences in lifespan, metabolism, composition, and other factors, might suggest “a simple sentence takes a human lifetime to communicate”. He emphasizes it will require the use of human inventions, including physics, art, and biology, along with patience, generosity, and imagination to converse with extraterrestrials.

Figure 2: Another example of an alien embracing a facet of humanity. Here a good guest, as per Oman-Reagan, would provide more alcohol.  Source: “American Dad”

This blogger agrees with the need for plenty of imagination and notes the apparent lack of imagination in Oman-Reagan’s article. If we assume extraterrestrial intelligence, then why does it have to share so many human qualities. There are various movies and games (i.e. Halo, Metroid, anything in Kirby) where aliens are not the most welcoming. While Oman-Reagan crafts an extraterrestrial like ET (Figure 1) or Roger (Figure 2), one amenable and accepting of humanity, he appears to have never watch any horror film concerning aliens. One in particular, the Xenomorph (Figure 3), would love for humans to generously host them and would show their appreciation when emerging through said host’s chest. To consider extraterrestrial hospitality also requires one to think of extraterrestrial rudeness and potential danger to humanity. While it certainly is comforting to apply anthropology and our understanding of human communication to extraterrestrials, if this view is as myopic as the one presented by Oman-Reagan, we may be in for a surprise.

Figure 3: It wants a host and I am sure no human would offer to be said host. Oman-Reagan appears to have no knowledge of the horrors parasitic aliens, such as the Xenomorph above, can bring. Source: “Alien: Covenant” 20th Century Fox

Would you like some ETea?

How do you welcome a stranger into your home? It can be an awkward experience, and how you greet them depends wholly on the cultural assumptions you make about them. In this conceptually unique (as far as I am aware) column by Oman-Reagan, we are invited to think about how the inevitable cultural differences between ourselves and visiting ETI would complicate relations and communications.

This paper is not directly related to SETI, but a reminder of how our human customs flavor how we think about possible future interactions with ETI. There are many assumptions we might inadvertently make about our visitors and these are absolutely critical to how well we will be able to communicate.

The column proposes several example scenarios that would render casual communication basically impossible. There are already many many dissimilarities between human cultures and one can have a lot of fun thinking about possible differences. Maybe ET’s way of greeting new friends is offering them a piece of their own appendage to be consumed or blowing some nice gasses that its biology produces at you.

One limitation of the column is its assumption that aliens have similar senses to ours. It seems reasonable that at the minimum, ETI will be able to sense at least some of the EM spectrum, but who knows if or how they directly sense nearby molecules (smell) or if they will have specialized organs for interpreting pressure waves in their surrounding media (hearing).

The Beastly Biases from the Planet Earth!

I was originally conflicted about Wright and Oman-Reagan (2017).

Initial Feeling 1: I think interdisciplinary work benefits all fields involved, and it isn’t performed enough. We are all too familiar with our own literatures (and thinking that we’re pretty up-to-date because of that); meanwhile another literature is examining the same problem from a different angle or (worse) just solving the same problem in parallel. And I’m not just talking about related fields (astronomy/geosciences, astronomy/engineering, etc.). I attended the Global Hands-On Universe Conference in 2016, which works at the intersection of science, art, and education, and found the experience and the motivation behind the conference to be extremely useful. My takeaway was that astronomers don’t pay nearly enough attention to education research and the benefits of art as a means of public communication and outreach.

Initial Feeling 2: I am an astronomer. I need to be hired by and funded by astronomers, and I need work to be done in my field to advance my understanding of it and to guide my own research interests and strategies. I need my peers to take my research as seriously as any other sub-field. And I think that papers that are too speculative will water down the field and make all of those goals harder to accomplish. Some of these claim to be astronomy papers (and have some good points) but are still filled with wild imaginings, others (this work included) are clearly outside the scope of a typical scientific paper as an astronomer would think of it and thus might be prone to the ‘giggle factor’.

Initial Resolution: I think the resolution of these two points of view is to place value on interdisciplinary work that tackles and tries to provide answers to problems in SETI – the literature needs work that strives to improve the search, regardless of discipline (such as this paper by Nathalie Cabrol). The other reading for this week was, to be fair, a popular science article, but I don’t believe that it’s a particularly useful piece as far as the search itself goes. If our SETI efforts are ever successful, then we’ll need scores of papers that consider how we might meet and receive extraterrestrial intelligences. Until then, the scientific discipline should focus on the search.

This paper is both necessary and useful as far as the search goes, even though it might seem on the surface to not be directly related (by way of Schelling points or search suggestions etc.). Improving public perception of the search is important: SETI needs to prove its place as a worthy discipline so that people know why it should receive funding. Improving the flux of a diverse crew of scientists into the field is important: this is always true, but especially in a field such as SETI, where we need the broadest perspectives and most open minds to try to get past a thousand insidious layers of anthropocentrism. Keeping an eye on how biases brought about through language and culture can affect the way SETI is performed is important: science does not exist in a vacuum, and scientists are sometimes loathe to admit that fact.

After attending the first Decoding Alien Intelligence workshop at the SETI Institute this year, my perspective on this issue has developed further. A conversation I had with Michael Oman-Reagan opened my eyes to some strong biases that the astrobiology community has come to accept as fact. Why did we start SETI with radio astronomy? Some solid engineering reasons, but also maybe because radio astronomy was in vogue in the 1960s. Why is Europa considered an extremely strong candidate for astrobiology? Maybe because it’s really cool and has promising features, but maybe (as David Grinspoon suggests) just because we’ve heard it repeated so much. Why are we suddenly sure that any life we find will be post-biological? Maybe more because the idea of AI is rooted in our culture right now and less because “it’s inevitable”. Why is machine learning the best technique for SETI research today? Maybe because it’s all the rage in Silicon Valley, where most SETI efforts are geographically located. Why do the aliens always watch I Love Lucy, for goodness’ sakes! The biases are everywhere, ahhhhh!

Hmmm, maybe there’s a paper in here somewhere…


As a final (somewhat unrelated) point on the topic of biases, I find it interesting to characterize METI as prideful/dominion-focused/arrogant and SETI as submissive/cautious. The language in the paper made me think of the two methods, for the first time, as somewhat tied to cultural ideas of masculinity and femininity. This made me realize that in SETI more than anything else, having a base of practitioners that are neither diverse nor aware of their own implicit biases is crazily dangerous. It would be a little ironic if the systematic biases that humanity has always fostered led to our planetary downfall, but I’d prefer not to laugh at that particular irony.