Avi Loeb is an Israeli-American theoretical astrophysicist who spent decades at Harvard University, including service as chair of its astronomy department and director of the Institute for Theory and Computation. His research has ranged across black holes, the first stars, cosmology, and the search for life beyond Earth. He has also been an unusually public advocate for examining unconventional astronomical hypotheses.

Loeb’s academic career long predates his public association with anomalous objects. He worked on the first stars, black holes, cosmology, and the formation of galaxies, eventually leading Harvard’s astronomy department and advising major scientific programs. His willingness to place unconventional possibilities inside formal papers made him unusually visible beyond astronomy. It also generated friction with colleagues who believed some of his public conclusions moved faster than the available measurements.

Loeb gained broad attention after arguing that the interstellar object 1I/‘Oumuamua might warrant consideration as artificial technology. Most astronomers favor natural explanations, but Loeb used the debate to argue that scientific institutions should collect better data rather than dismiss technological possibilities in advance. He later founded the Galileo Project, an effort to deploy instruments for studying unusual objects near Earth, and led an expedition that recovered small spherules from the Pacific while searching for material associated with an interstellar meteor.

His work overlaps with UAP through method rather than through endorsement of every disclosure claim. Loeb calls for calibrated sensors, open data, and physical samples that can be tested. Critics question some of his interpretations and publicity, while supporters see a scientist willing to investigate neglected possibilities. He represents the attempt to translate questions about non-human technology into observational astronomy and reproducible measurement.