A recent study proposes that advanced extraterrestrial beings might be engaged in sightseeing Earth’s significant landmarks.
The research suggests that certain types of highly developed extraterrestrial entities, located at a considerable distance, could potentially identify buildings—but only those from around 3,000 years ago, owing to the time it takes for light to traverse the vastness of the universe.
The peer-reviewed paper, titled “Are we visible to advanced alien civilizations?,” is featured in Acta Astronautica Journal Overview.
Z.N. Osmanov, the author and a Research Affiliate at the Search for Extraterrestrial Intelligence (SETI) institute, posits that by leveraging the universality of the laws of physics, the maximum distance for potential detection is approximately 3,000 light-years.
This implies that extraterrestrial observers might utilize extensive telescopes to discern the architectural marvels of major civilizations from the past, including the Romans, Greeks, and Egyptians.
In addressing the question of our visibility, the study categorizes the technological advancement level of an alien civilization, with a focus on those capable of fully harnessing the energy of their local star.
It is hypothesized that there might be three major technological civilizations: Type-I is an alien society that consumes the total energy incident on a planet from their host star; Type-II is an extraterrestrial civilization utilizing the total energy of the star; and Type-III is an advanced alien society, that consumes the total galactic energy.
The study reads: “In particular, the question is: can the artifacts of our technological society be visible and potentially detectable by the telescopes of ETs?
“Since the question is to identify our society with civilization, the major focus should be on the search for large ships, buildings and space satellites, etc. Such artifacts might easily be identified as artificial constructions.
“For this purpose, it is natural to focus on the visible light reflected from the corresponding objects. To identify an observed object with an artificial one, the best way is to spatially resolve it. Therefore, optical telescopes will be used.”
Further suggestions for the potential observation are several alien telescopes working together or super-advanced computations.
The study says: “Instead of using large telescopes of astronomical sizes, one can apply long-baseline optical interferometry by using at least two telescopes separated by a huge distance.
“We have shown that Type-I, II, III advanced alien societies might use quantum computers based on artificial black holes, which are able to record the mentioned signals.”