Before leading Trump's UFO panel, Israeli-American Harvard astrophysicist Avi Loeb proposed these 5 splashy theories about alien life

Harvard astrophysicist Avi Loeb, known for polarizing theories that some mysterious objects entering our solar system could have extraterrestrial origins, is back in the spotlight after being chosen to lead the Trump administration's newly formed scientific advisory panel examining unidentified aerial phenomena (UAP), commonly known as UFOs.

According to the Associated Press, Loeb and a hand-picked team of scientists have already begun reviewing the origins of unexplained aerial objects and have requested dozens of Pentagon videos, images, and documents related to reported UAP encounters. The panel, which meets behind closed doors, will report its findings directly to the White House as the administration continues releasing previously classified UFO records.

Loeb, a former chair of Harvard University's astronomy department, said to AP that he hopes the appointment will encourage a more scientific approach to investigating unexplained sightings. "My impression is the government is baffled by not being able to infer the nature of some of these objects," he said.


While Loeb remains one of the world's most accomplished astrophysicists, he has also become one of its most polarizing figures. His willingness to publicly entertain the possibility of extraterrestrial technology has repeatedly sparked debate within the scientific community, with critics arguing that many of his conclusions go beyond the available evidence.

Here are five of Avi Loeb's most controversial theories that have divided scientists and fascinated space enthusiasts.

1. ʻOumuamua may have been alien technology

Loeb first captured global attention after the interstellar object 1I/ʻOumuamua passed through the solar system in 2017. While most astronomers concluded the object was an unusual but naturally occurring body, Loeb argued that some of its properties, including its shape, acceleration, and lack of a visible cometary tail, were consistent with artificial technology such as a light sail or extraterrestrial probe.

In his 2021 research paper, On the Possibility of an Artificial Origin for ʻOumuamua, Loeb wrote: "The possibility of an artificial origin for ʻOumuamua must be considered."

Most astronomers, however, maintain that natural explanations remain far more likely and say there is no evidence the object was technological.

2. The Pacific Ocean spherules could be fragments from an interstellar object

In 2023, Loeb announced that his expedition had recovered roughly 700 microscopic metallic spherules from the Pacific Ocean near the estimated impact site of IM1, the first officially recognized interstellar meteor.

He argued that several of the samples displayed an unusual chemical composition enriched in beryllium, lanthanum, and uranium, what he called the "BeLaU" pattern, which, together with IM1's exceptionally high speed, supported an extrasolar origin.

Loeb described the discovery as the first laboratory analysis of material from an object originating outside the solar system and suggested it challenged earlier assumptions that IM1 was an ordinary meteor.

Critics, however, said there is no evidence the recovered material represents extraterrestrial technology and questioned both the interpretation of the chemical signatures and whether the spherules originated from IM1 at all.

3. 3I/ATLAS could be more than a normal comet

Loeb has also proposed that the recently discovered interstellar object 3I/ATLAS possesses numerous unusual characteristics that deserve serious scientific investigation.

According to Loeb, the object exhibits 15 anomalies involving its orbit, timing, brightness, polarization, jets, composition, and apparent non-gravitational acceleration. He has suggested these features could be consistent with an artificial probe capable of releasing technological devices near Jupiter's Hill sphere or even dispersing biological material between planetary systems.

Rather than claiming the object is definitively artificial, Loeb argues that it is sufficiently unusual to warrant an open-minded investigation and that future spectroscopic observations of its jets may determine whether they originate from natural cometary activity or something resembling technological propulsion.

4. Interstellar objects may spread life across the galaxy

Beyond searching for alien technology, Loeb has argued that interstellar objects like 3I/ATLAS could transport biological material between star systems.

The idea builds on the long-discussed scientific hypothesis of panspermia, the possibility that microscopic life can travel through space inside rocks or icy bodies and seed life elsewhere.

Although panspermia remains a legitimate scientific hypothesis, there is currently no direct evidence that any known interstellar object has transported life between planetary systems.

5. Humanity must become an interstellar civilization

Loeb has repeatedly argued that humanity should think beyond Earth and become an interstellar civilization as quickly as possible.

He believes keeping humanity confined to a single planet poses an existential risk and has described Earth as vulnerable to catastrophic events ranging from pandemics to asteroid impacts. In his writings, he has argued that searching for extraterrestrial civilizations and investigating unusual interstellar objects are part of preparing humanity's long-term future beyond Earth.

According to Loeb, discoveries involving objects such as 3I/ATLAS are important not only because they may reveal new astrophysics but also because they could reshape humanity's understanding of its place in the universe.

Who is Avi Loeb?

Avi Loeb is a prominent and polarizing Israeli-American theoretical physicist and Harvard University astronomer. He is the former chair of Harvard's Astronomy Department and leads the Galileo Project, which is dedicated to the scientific search for extraterrestrial technological artifacts. He earned his PhD in physics from the Hebrew University of Jerusalem at the age of 24 and has published more than 1,000 scientific papers covering black holes, the first stars, cosmology, extraterrestrial life, and the future of the universe.

Loeb previously served as the longest-serving chair of Harvard's Department of Astronomy, founded the university's Black Hole Initiative, and currently directs the Institute for Theory and Computation at the Harvard-Smithsonian Center for Astrophysics. He also heads the Galileo Project, an international effort to scientifically study unidentified aerial phenomena and search for potential extraterrestrial technological artifacts.

In addition to authoring the bestselling books Extraterrestrial and Interstellar, Loeb has served on several high-profile scientific advisory bodies, including the White House's President's Council of Advisors on Science and Technology (PCAST), and chaired the Breakthrough Starshot Initiative, which aims to develop technology capable of reaching nearby star systems.