Journal of the British Interplanetary Society, vol. 30, pp. 466-9, 1976.

After it was published this paper seems to have fallen into utter obscurity. It was pure serendipity that led me to stumble across it.

All that I can determine about John Armitage is that he became a Fellow of the Royal Astronomical Society on 10 December 1976[1], and that the paper was also presented at the Second British Interplanetary Society Conference on Interstellar Travel and Communication, 4-5 April 1977.

In it the author argues, as I have, that it seems likely that the number of galactic extinct civilizations is greater than the number of galactic extant civilizations. Armitage makes the distinction that detectable civilizations are only apparently extant, given the relativistic gap between signal transmission and detection.

Armitage describes two linked disciplines: astro-palaeontology and astro-archaeology, the first being concerned with non-sapient life. Astro-palaeontology is of interest to xenoarchaeology (and this blog) when tracing the evolution of sophonts. As Alun Salt pointed out recently, the line between palaeontology and archaeology is blurred, and indeed Armitage illustrates this continuum in his article.

Warning against too-close a reliance on terrestrial analogy, which might blind researchers to other possibilities in studying extraterrestrial sites, Armitage offers the cautionary hypothetical of non-indigenous life forms being introduced to a planet:

The most striking and readily identified example of this condition would be a case involving the sudden appearance of a high technology culture which was completely incongruous with the fossil record and lines of evolutionary development established to be indigenous to the planet.

I’m reproducing in full Armitage’s table of the types of remains that might be discovered:

Level of Organisation Indicated by the Remains Type of Remains Method of Evaluation
Pre-Biological Activity “Chemical” Fossils Geochemistry
Early Acellular Microscopic remains in well-preserved material Electron Microscopy
Simple Metazoan Grade Soft parts or hard parts depending upon morphology and mode of preservation Microscopic or macroscopic depending upon nature of remains
Advanced Metazoan Grade (non-intelligent) Similar to terrestrial fossil remains? Normal palaeontological techniques with any appropriate modifications as required
Advanced Metazoan Grade (intelligent) Evidence of a civilisation in the form of artifacts Archaeological, technological and sociological analysis
Advanced Intelligent (non-indigenous) High technology artifacts which are incongruous with any fossil record or evolutionary history on the world concerned Archaeological, technological and sociological analysis
Very advanced spacegoing (“Dyson Sphere” Grade)+ Many high technology artifacts including major astro-engineering structures Remote detection by astronomers

More recent scholars might suggest a category for postbiological remains, although the last three could be suitable.  Armitage actually does argue for the possible existence of “‘robot civilisations’ which would in a sense be the extension of the intelligence which created them, though the biological organisms had died out.” It’s not clear from this whether he’s referring to sapient machines or automata.

It’s very interesting to see the search for Dyson spheres included. Although the idea of searching for them had been around for 16 years, the context of a space archaeology paper is novel for 1976 I think.

Also of particular interest is this mention of a question astro-archaeology might ask: “Do the studies throw any light on the life-expectancy of an intelligent civilisation?” This is part of the Drake equation of course, and the attempt to quantify the elements of that equation is a matter of some importance to the SETI community.

Larry J. Paxton’s paper in the Handbook of Space Engineering, Archaeology and Heritage, ‘Space archaeology and science fiction’, is an excellent follow-up to Armitage’s, using modified versions of the Drake equation to try and calculate the number of possible sites in our galaxy that contain fossil remnants of life, and also the number of sites that contain cultural or technological artefacts.

In his conclusion, Armitage writes:

… our questions regarding the nature of extraterrestrial life forms and civilisations might well be more rapidly answered by means of Astro-Palaeontology or Astro-Archaeology than by direct exobiology investigations of currently existing alien life forms, or in the case of extraterrestrial intelligence by classic “active” or “passive” CETI experiments.

This might sound optimistic, even to space archaeology and SETT enthusiasts, but then again we still haven’t received a result from traditional SETI or astrobiology.