Avi Loeb, professor of astronomy at Harvard University and co-founder of the Galileo Project, has just published a report on the “First Year of the Galileo Project”. Its mission is defined as follows:
The goal of the Galileo Project is to bring the search for extraterrestrial technological signatures of Extraterrestrial Technological Civilizations (ETCs) from accidental or anecdotal observations and legends to the mainstream of transparent, validated and systematic scientific research. This project is complementary to traditional SETI, in that it searches for physical objects, and not electromagnetic signals, associated with extraterrestrial technological equipment.
The project is pursuing three main branches of investigation:
Constructing new telescope systems to infer the nature of Unidentified Aerial Phenomena (UAP), similar to those mentioned in the ODNI report to the US Congress.
Designing a space mission that will identify the nature of interstellar objects that do not resemble comets or asteroids, like ‘Oumuamua.
Coordinating expeditions to study the nature of interstellar meteors, like CNEOS 2014–01–08.
The latter item is intriguing:
The first interstellar meteor, CNEOS 2014–01–08, detected on January 8, 2014 by US Government sensors near Papua New Guinea. It was half a meter in size and exhibited material strength tougher than iron. It was an outlier both in terms of its speed outside the Solar system (representing the fastest five percent in the velocity distribution of all stars in the vicinity of the sun) and its material strength (representing less than five percent of all space rocks). The Galileo Project plans an expedition to retrieve the fragments of this meteor from the ocean floor in an attempt to determine the composition and structure of this unusual object and study whether it was natural or artificial in origin.
The paper discusses the probability of success in discovering technological artefacts, noting that unlike radio or optical SETI, there is no requirement that the two technological civilisations be active at the same time, as artefacts have a very long lifetime in space and can be expected to accumulate in the galaxy even if the civilisations of their makers were short-lived. If some of the artefacts were self-replicating, they may be abundant.
We’ll never know if they’re there unless we look.