The Search for Extraterrestrial Artefacts


WHAT ARE EXTRATERRESTRIAL ARTEFACTS?

Conventional archaeology studies human artefacts on the Earth. However, there are now human artefacts on other celestial bodies (eg the Moon and Mars). These might be referred to as extra-terrestrial artefacts.

Another class of extraterrestrial artefact might be artefacts left behind as a result of an alien culture that had either visited the Earth or a body near the Earth, or that had sent a probe to Earth or the space near the Earth. Even if the artefact was found on the Earth it would probably be called an extraterrestrial artefact because it was the result of activities of an extraterrestrial culture.


HOW TO RECOGNISE AN ETA

  1. Alien cultures may be so alien that terrestrial artefacts provide no reliable guide for identification purposes.

  2. “Anything that differs substantially from nature” may be the best guide. But an advanced ecologically sensitive culture might ‘blend’ with nature and be almost indistinguishable from ‘natural’ forms.

  3. Regularity, linearity, arrangement, departure from randomness are all criteria that might be employed and can be investigated mathematically


WHERE TO SEARCH

  1. Earth is a very ‘active’ planet, both geologically and meteorologically. Artefacts left in the distant past are thus very unlikely to be found or if found, to be in a recognisable form.

  2. The Moon is the least active of our neighbouring celestial bodies and may be a good place to search.

  3. Mars may well be the next best place to search although it is meteorologically active.

  4. It is not necessary to be physically present on these bodies to search. The resolution of lunar and martian orbital imaging spacecraft is now sufficient that human artefacts can be seen. This imagery is also available to the public.

  5. A recent paper has even suggested that such searches should be undertaken (Davies & Wagner, 2013).


LUNAR SEARCHES

The image below was taken by the Lunar Reconnaissance Orbiter of the Apollo 11 site, showing artefacts left behind by the astronauts.

Some people have claimed that ET left an image of a 'face' on Mars, on the basis of a Viking 2 Orbiter image of the Cydonia region of the planet.

Carl Sagan gave good advice in trying to evaluate such claims:

"Extraordinary claims require extraordinary evidence."

And indeed a higher resolution image and images taken at different angles do not show a face.

It has also been said that ETs are currently present on the Earth. This claim is addressed in the article on UFOs.


REFERENCES

Robert A Freitas & Francisco Valdes, “The Search for Extraterrestrial Artifacts”, Acta Astronautica, 12, 1027-1034 (1985)

Paul Davies & RV Wagner, “Searching for Alien Artifacts on the Moon”, Acta Astronautica, 89, 261-265 (2013)


FICTION

Arthur C Clarke, The Sentinel, (short story) Avon Periodicals 1951.




ASAAustralian Space Academy