Avi Loeb

Abraham «Avi» Loeb (b. 1962, Israel) is a theoretical astrophysicist and, since 1993, a professor at Harvard University, where he holds the Frank B. Baird Jr. Chair of Science. He chaired Harvard's Astronomy Department for nearly a decade (2011–2020), founded the Black Hole Initiative, and heads the board of the Institute for Theory and Computation at the Harvard-Smithsonian Center for Astrophysics. His peer-reviewed output —hundreds of papers on the first black holes, the formation of the earliest stars, exoplanets and cosmology— places him, by conventional credentials, among the most-cited astrophysicists of his generation. That institutional standing is exactly what makes his turn toward the UAP problem relevant to the corpus: he is not an outsider but the scientific establishment asking the question out loud.

The turning point came in October 2017, when the Pan-STARRS telescopes detected 1I/ʻOumuamua, the first confirmed interstellar object passing through the Solar System. Loeb argued —in papers and then in the popular book «Extraterrestrial» (2021)— that several of the object's anomalies (its extreme shape, its non-gravitational acceleration without a visible cometary tail, its high brightness) were consistent with an artificial light sail, and that the technological hypothesis deserved serious consideration rather than a priori dismissal. The planetary-science community mostly responded with natural explanations (a hydrogen- or nitrogen-rich comet, a porous aggregate), and the controversy remains open. Loeb's value to the debate is not that he «proved» anything, but that he forced a methodological discussion: what evidence would be required to treat the technological hypothesis as science rather than taboo.

In 2021 Loeb founded the Galileo Project, a research program with dedicated telescopes and sensors that systematically searches, with open data, for three things: interstellar objects like ʻOumuamua, possible artifacts of non-human origin, and UAP in Earth's atmosphere. Its stated philosophy is to invert the logic of the field —replacing testimony and declassified videos with calibrated scientific instrumentation and peer review. In 2023 he led an expedition to the Pacific Ocean off Papua New Guinea to recover fragments of the interstellar meteor IM1 (CNEOS 2014-01-08); the metallic spherules collected and their composition triggered a fresh round of dispute over whether they were interstellar or terrestrial/industrial contamination.

For the UAP Codex map, Loeb embodies the «open-scientific» narrative: neither state cover-up nor certainty of visitors, but the demand to apply the method to the phenomenon. He is also a figure of the emerging institutional ecosystem —linked to the Sol Foundation and the academic conversation around AARO— who lends disciplinary legitimacy to the subject. His most persistent criticism comes from colleagues who feel he over-interprets anomalies and communicates conclusions before the evidence supports them; his defense is that science advances precisely by testing bold hypotheses against data, not by silencing them.