On a morphology of contact scenario space

The purpose of this paper is to explore the possibility space of scenarios of 'contact'-the discovery of extra-terrestrial life, whether intelligent or not-using a morphological approach utilising seven principal parameters, chosen both for their descriptiveness of the scope of possibilities, as well as for their relevance in examining potential societal impacts arising from different scenarios, including, for example, the proximity of the discovery. Several classes of contact scenario are examined, and existing approaches to the search for extra-terrestrial life and intelligence are situated within the range of possible search strategies and targets illuminated by this particular choice of parameters, as are some examples of contact scenarios from popular culture. The resulting possibility space can also suggest new search strategies and potential targets, one of which is highlighted-that of 'galaxy-scale macro-engineering'. It is hypothesised that an example of this might already be known to us, namely the intriguing galaxy 'Hoag's Object' (PGC54559), and some specific empirical observations are suggested in order to test this hypothesis. Some possible extensions to the parameters used, as well as some preliminary observations about modelling the range and extent of human societal responses to contact, are also made.