A new study shows that the spherules known as BeLaU, recovered from the fall of the first identified interstellar object during a 2023 expedition by Harvard scientists in the Pacific Ocean, are indeed unique.

Between June 14 and 28, 2023, Professor Avi Loeb, leader of Harvard’s Galileo Project, led an expedition to the Pacific Ocean to recover fragments of the meteor IM1, listed by NASA in the CNEOS fireball catalog and confirmed as interstellar in origin by the U.S. Space Command.

During the expedition, spherules, small molten droplets, were collected and underwent detailed analysis at the state-of-the-art geochemistry laboratory of Professor Stein Jacobsen, also at Harvard.

On January 8, 2014, the interstellar meteor IM1 entered Earth’s atmosphere, producing three atmospheric detonations detected by U.S. government satellite sensors about 84 km north of Manus Island. Analysis of the event suggested the object was interstellar due to its entry speed exceeding 45 km/s, which later motivated the Pacific expedition led by Professor Loeb to recover its fragments.

During the expedition, 850 spherules were recovered, ranging in diameter from 0.05 to 1.3 mm. Most (~80%) were known cosmic spherules, classified as type S, type I, and type G, originating from familiar chondrites. A fraction of the material, however, did not fit these categories and was classified as type D, due to its differentiated composition, with a low magnesium-to-iron ratio.

About half of the type D particles were designated BeLaU, exhibiting extraordinary enrichments in beryllium (Be), lanthanum (La), and uranium (U)—elements rare in the Solar System. The composition of the BeLaU spherules remains unknown, possibly interstellar in origin, underscoring the unique nature of the recovered fragments.

Images of the spherules, composed of an anomalous alloy that is neither natural to Earth nor human-made, show that they are indeed extraterrestrial.

Some skeptics suggested that the BeLaU spherules could be coal ash or tektites, glassy rocks formed by meteorite impacts. However, detailed analyses conducted by Loeb’s team showed that the composition of BeLaU does not match any of these terrestrial materials, reinforcing their unusual and possibly interstellar nature.

This week, Dr. Eugenia Hyung from Jacobsen’s laboratory led a paper, co-authored by four students, Stein, and Loeb, presenting precise elemental data on Australasian tektites to test the second hypothesis raised by skeptics. The study concluded that these tektites closely resemble the elemental abundance pattern of Earth’s upper continental crust for all analyzed elements and are very different from the composition of the BeLaU spherules.

This analysis refutes the suggestion by some skeptics that the BeLaU spherules could originate from Australasian tektites or microtektites in lateritic soils. Tektites are glassy droplets formed by meteorite impacts and generally derive from regions with composition similar to Earth’s upper continental crust. To test this hypothesis, Loeb’s team analyzed four representative tektites from Australia and compared their elemental abundances with those of the BeLaU spherules.

Comparison of four Australasian tektite samples with BeLaU fragments from the interstellar meteor site. Clearly, the two materials are different. (Credit: E. Hyung et al. 2025)

The results showed that while the tektites have a composition similar to Earth’s crust, the BeLaU spherules display very distinct enrichment patterns in elements such as beryllium, uranium, and molybdenum. Direct comparison made it clear that Australasian tektites and microtektites cannot account for the unique composition of BeLaU.

Additionally, the composition of BeLaU also differs from laterites, soils rich in iron and aluminum oxides formed by intense weathering. In summary, detailed analyses indicate that speculations about a terrestrial origin for BeLaU are unfounded, reinforcing their possible interstellar origin.

The team emphasizes that new scientific knowledge does not come from critics or influencers, but from rigorous research. Paraphrasing John F. Kennedy’s Moon speech, Professor Loeb said:

“We chose to go to the IM1 site in the Pacific Ocean and carry out the related scientific analyses, not because they are easy, but because they are hard; because this goal will serve to organize and measure the best of our energies and skills, because this is a challenge we are willing to accept, one we are not willing to postpone, and one we intend to win, and others as well.”

Images of the spherules, composed of an anomalous alloy that is neither natural to Earth nor human-made, show that they are indeed extraterrestrial.

At the time, Professor Loeb’s hypothesis that these fragments were interstellar and could be debris from a non-human craft generated significant attention and widespread discussion in both scientific and popular media. News outlets often highlighted the extraordinary suggestion that the BeLaU spherules could represent material of alien technological origin.

The claim sparked debates among scientists and skeptics. Some praised the rigorous analysis and the unprecedented nature of the samples, while others criticized the more speculative aspects, emphasizing the need for further evidence before linking the fragments to extraterrestrial technology. On social media, videos, articles, and discussions reached a global audience, making the discovery a high-profile topic in both scientific and UFO-related communities.

Despite the controversy, analyses conducted by Loeb’s team — including the rejection of terrestrial sources such as coal ash, tektites, and laterites — strengthened the case for the fragments’ interstellar origin, keeping scientific and public interest alive. The story also opened a broader discussion about the possibility of encountering space-based technological material on Earth, generating both excitement and caution.