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An active catalogue of material culture artefacts and ‘messages’ in local, interplanetary and interstellar space – documenting the range of purposeful electromagnetic signals, space-time archives, and other deposition activities, sent off-world for various social, ceremonial and communicative applications.




Imagine finding a written cultural document, or detecting a strange encoded signal, that has been travelling through space for centuries. What could the ‘message’ mean? Who sent it? Why? How could we glean anything useful from our knowledge of it? Why is it relevant for us? What could be reliably known, about something that is completely unknowable? How do we ensure our interpretation does not socially construct knowledge about others? We often ask these crucial questions when contemplating reception of signals from extraterrestrials, or discovering purposeful material evidence from our own species’ antiquity. But, seldom do we discuss how we are now authoring a chronological landscape of these communicative records; cultural documents that intend to purposefully operate far from the spatiotemporal shores of Earth, for a variety of envisioned recipients, and agendas.

Space messages have often been considered as intriguing, material representations for Earth. They are designed, essentially, as a means of delivering adequate information about present day generations of humanity to foreign extraterrestrial intelligences, or as a variant of time capsules; intent on conveying a snapshot of our contemporary societies to others far removed from today’s traditions and cultural histories. Often, these intentions are mixed, unwittingly or otherwise. Other times, these are simply intended as immortalising ‘gestures to eternity’, intent on preserving material traces of their creator's minds and thoughts beyond their individual lifespans. How might these devices, one day, reflect our ages, values, attitudes, and social customs?

The Voyager Golden Records, while not the first extension of cultural resources dispatched into distant space, continues to be the source of much inspiration – and human oversights – within semiotics, linguistics, and associated fields of the humanities and social sciences. We often overlook these partialities of humanity, and how they tend to warp, and favourably intermix any rational interpretation of the media we use as representational signs for Earth. Examples of these issues are abound; the sensory limitations to extract information through human visual and other sensory channels; the cultural partiality of some contents that will prove challenging to recipients; often misplaced confidence in ‘the language of our science’ to intelligibly communicate aspects of semiotics; and a tendency to sanitise these accounts of Earth to represent an idealist version of [primarily] our species, and [secondly] our planet.

Moreover, much of these early, conventional decisions have now become entrenched as a social history of crafting messages; customs that continue to reshape us in return. The scope of recent research across the humanities and social sciences reveal another, deeper schism between disciplinary positions, and how differences in evidence acquisition, data interpretation, and subject orientations, play key roles in contributing to the confusing reflections of humanity embedded in our messages. This is not only apparent within messages intended for extraterrestrial intelligences, but also across the range of space-time capsule artefacts, and other deposition activities which attempt to time-bind the human species across centuries or millennia – with archives left in orbit, on the Moon, or much further afield.


The underlying emphasis of the original ‘A Profile of Humanity’ (APOH) catalogue was to document a broad range of intentional activities that collectively contribute to the exoatmospheric archaeological record, but it’s foundation principally stems from two moral complexities raised across three recent papers (Billingham and Benford, 2011; Brin, 2013; Harrison, 2014). On the one hand, there are a number of fundamental ethical concerns associated with sending messages into space on behalf of humankind; of which the perennial controversy of Messaging Extra-Terrestrial Intelligence (METI) with de novo transmission strategies perhaps best illustrates the existentialism of this discourse (Zaitsev, 2008; Musso, 2012; Brin, 2014; Korbitz, 2014; Gertz, 2016a; 2016b). The other hand presents us with a more pragmatic yet very terrestrial issue that should continue to occupy our minds regardless of how the METI debate or similar extraplanetary contamination discussions unfold; how do we ensure those unborn generations, who do not readily ‘have a say’ over our messaging activities or other techno-cultural fait accompli, are adequately informed about the inherited legacies of such decisions committed on their behalf? – often amusingly referred to as the ‘unordered pizza’ argument.

There have been some assessments performed by the SETI and METI communities (Vakoch, 2009; Zaitsev, 2012; Dumas, 2015) who responsibly document intelligible, electromagnetic envoys that intend to initiate diplomatic relations on behalf of Earth’s populace over intervals of deep time. But these accounts are not comprehensive, nor do they take into account the other non-extraterrestrial messages that also constitute this growing technosignature. There are many applications that presently contribute to this intentional celestial property of our planetary system; our desires to create secure ‘eternal memory’ libraries to preserve information beyond our terrestrial environment (Guzman et al., 2015), rational communication attempts with extraterrestrial intelligences (Zaitsev, 2006), expressions within ‘SpaceArt’ (Paglen 2012), mission outreach initiatives (Sutherland, 2015), techno-colonialist propaganda objects as ideological claims in the ‘higher frontier’ (Reeves, 1994), questionable ‘lifeboat’ projects to conserve libraries of life beyond Earth, and also symbolic gestures devised to impart some profound heuristic about our observed position within the universe (Schulze-Makuch, 2016). These activities clearly do not represent equivalent degrees of ‘plausible risk’ as those frequently cited for METI, but they do possess other significance for our enduring exoatmospheric archaeological record, alongside our increasing ‘bio-footprints’, and other residual legacies we may still need to uncover. Technological activities seemingly far outpace ethical foresight.

The APOH catalogue was initially established as a first step within the Beyond the Earth foundation’s broader programme to preserve the memory of such ‘essential’ material legacies in order to allow distant future generations of our species to commit informed stewardship decisions on behalf of their civilisations or, in a more likely scenario, contribute insights for historical examinations of their ancestor’s material culture legacies. This particular catalogue was informally compiled and presented at the 2018 UK SETI Research Network symposium in Oxford University before being later published in the International Journal of Astrobiology (Quast, 2018). However, documenting METI is not this catalogues sole function. The range of materials now representing the populations of Earth is vast and exponentially increasing which, in addition to the startling rise in contemporary proposals for other deposits to fulfill a range of applications, inherently tells us something about ourselves, our underlying intentions, behavioural patterns, customs, and frequent oversights committed in our desire to find exotic, imagined audiences.

This second edition of the APOH catalogue has been consolidated as part of a much broader study for the publication Beyond the Earth: messaging into deep space and cosmic time (Quast et al., forthcoming), a volume that aims to continue to chronicle and examine the lengths we take in fabricating mnemonic artefacts of material culture which varyingly attempt to ensure our civilisation is contemplated throughout time and space–by distant, spatiotemporal observers that we may not distinctively recognise as ‘human’.

Page last updated: 07 Jul 2021


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