Avi Loeb has done cutting edge work in the fields of theoretical cosmology and motivated reasoning

The failure of the press to keep its wits during the recent reemergence of UFO mania has come down in no small part in its inability to think clearly about credentials, be it government official, decorated pilot, NYT reporter, or Harvard astrophysicist. 

Avi Loeb has the kind of resume that really screws with journalists, highly impressive, but when you think about it, not quite as relevant as it first seems. On one level, he is a legitimately major player, responsible for seminal work, so when he claims to have convincing evidence that we've directly observed alien technology, you can can understand why reporters felt safe running credulously with the big, fun story. But the coverage often downplayed just how far out of the mainstream Loeb is on this subject, and almost completely omitted the fact that he wasn't an expert in the fields of astronomy and astrophysics that were relevant here.

Jason Thomas Wright, a professor in the Department of Astronomy and Astrophysics at Pennsylvania State University, and director of the Penn State Extraterrestrial Intelligence Center, has taken a lead role in trying to tamp down the hype. He previously co-authored the excellent "Oumuamua: Natural or Artificial?" He has updated that with a blog post which is considerably more blunt and reflects the community's waning patience with Loeb.

From "Avi and Oumuamua: Setting the Record Straight"

Loeb, you might know, recently rose to public prominence with his claims that the first discovered interstellar comet, ‘Oumuamua, is actually a piece of an alien spacecraft passing through the Solar System.  Since then he has headlined UFO conventions, written a very popular book about his claim, and raised millions of dollars to study UFOs with his “Galileo Project” initiative. His latest venture with that money is to sweep a metal detector across the Pacific to find fragments of what he claims is another interstellar visitor that the US military detected crashing into the ocean, resulting in the headline “Why a Harvard professor thinks he may have found fragments of an alien spacecraft” in the Independent.  

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But his shenanigans have lately strongly changed the astronomy community’s perceptions of him. His recent claims about alien spacecraft and comets and asteroids largely come across to experts as, at best, terribly naive, and often as simply erroneous (Loeb has no formal training or previous track record to speak of in planetary science, which has little in common with the plasma physics he is known for). His promotion of his claims in the media is particularly galling to professionals who discover and study comets, who were very excited about the discovery of ‘Oumuamua but have found their careful work dismissed and ridiculed by Loeb, who is the most visible scientist discussing it in the media.

Most recently, his claims to have discovered possible fragments of an alien ship in the Pacific  have been criticized by meteoriticists at a recent conference. Loeb claims the metallic spherules he found trawling the ocean floor are from the impact site of an interstellar object (dubbed 20140108 CNEOS/USG) but they point out that they are much more likely to have come from ordinary meteorites or even terrestrial volcanoes or human activities like coal burning ships or WWII warfare in the area. And, they argue, 20140108 most likely did not come from outside the Solar System at all. (It also appears that Loeb may have violated legal and ethical norms by removing material from Papua New Guinean waters—you’re not supposed to just go into other countries and collect things without permission.) 

Also frustrating is how Loeb’s book and media interviews paint him as a heroic, transformational figure in science, while career-long experts in the fields he is opining on are characterized as obstinate and short-sighted. His Galileo Project has that name because it is “daring to look through new telescopes.” In his book claiming ‘Oumuamua is an alien spacecraft, he unironically compares himself to the father of telescopic astronomy, Galileo himself. The community was aghast when he blew up at Jill Tarter, a well-respected giant in the field of SETI and one of the best known women in science in the world. (When Tarter expressed annoyance at his dismissal of others’ work in SETI, he angrily accused her of “opposing” him, and of not doing enough for SETI, as if anyone had done more! Loeb later apologized to Tarter and his colleagues, calling his actions “inappropriate”).  

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So it is against all of this background that, even when asked, I have generally stayed quiet lately when it comes to Loeb, or tried to give a balanced and nuanced perspective. I do appreciate that he is moving the scientific “Overton Window”, making SETI, which used to (unfairly) seem like an outlandish corner of science, seem practically mainstream by comparison. I appreciate the support he’s given to my work in SETI, and I generally discourage too much public or indiscriminate criticism of him lest the rest of the field suffer “splash damage.”

I have noticed, however, that Loeb’s work and behavior have been seen as so outrageous in many quarters that it essentially goes unrebutted in popular fora by those who are in the best position to explain what, exactly, is wrong about it. This leaves a vacuum, where the public hears only Loeb’s persuasive and articulate voice, with no obvious public pushback from experts beyond exasperated eye-rolling that feeds right into his hero narrative.