In mid-2023, Harvard astrophysicist Avi Loeb claimed to have found interstellar debris on the floor of the ocean north of Australia. After previously identifying the location of a possible interstellar meteorite fall in 2014, Loeb had instigated an expedition to use a magnetic sled to pick up the metal spherules expected to have been left behind after the disintegration of the object from space.
After the expedition Loeb claimed to have successfully found those interstellar spherules – and whatsmore, that the strange elemental composition of the spherules could suggest an artificial origin…that is, that the interstellar meteor might even have been an alien spaceship or probe.
Skeptics however were quick to point out a number of issues with the expedition and analysis:
- The seismic data used to locate the meteorite was not complete enough for accurate evaluation – and may even have actually been caused by a truck driving past the sensor.
- The spherules could well have been produced on Earth, not an interstellar source.
- The subset of spherules containing ‘anomalous’ elements, such as beryllium, lanthanum, and uranium (‘BeLaU’) might have been caused by contaminents from coal ash.
Despite the skepticism from many in the scientific community, Loeb has recently reported that his team’s paper analysing the tiny spherules found – “Chemical classification of spherules recovered from the Pacific Ocean site of the CNEOS 2014-01-08 (IM1) bolide” – has been accepted for publication in the prestigious peer-reviewed journal Chemical Geology. He has summarised the findings in the paper in an article at Medium:
The retrieved samples were studied by state-of-the-art laboratory instruments including a micro-X-Ray Fluorescence analyzer, Electron Probe Microanalyzer and an Inductive-Coupled-Plasma Mass-spectrometer. We identified 78% of the spherules as primitive with a composition that resembles the primordial material that made the solar system. When rocky planets like the Earth or Mars form with a hot molten rock (magma or lava ocean) on their surface as a result of bombardment by large bodies, some elements from the periodic table which have a chemical affinity to iron migrate towards the iron core and leave behind a modified abundance pattern, which we labeled as “differentiated”. Our analysis revealed that 22% of our spherules were differentiated.
Among the differentiated spherules, about half, namely 10% of the total number of spherules, had a chemical composition that was never reported before in the scientific literature, characterized by an enhanced abundance of some elements up to a thousand times larger than the standard solar composition. We labeled this special set: “BeLaU”-type spherules. The BeLaU composition is unfamiliar and different from the composition of the crust of the Earth, Mars, the Moon, asteroids and comets and potentially flags an origin from outside the solar system. This origin is unknown.
While he doesn’t mention the criticisms of other scientists mentioned earlier, it is worth noting that the paper does address the question of whether the BeLaU spherules are actually just a result of coal ash contamination: Loeb’s team claims that after comparing “the average composition of BeLaU spherules for 55 elements with the SRM1633a coal fly ash standard”, they found that they sometimes differed “by factors of about 10 to 100”, and thus – they claim – the “BeLaU spherules do not have the composition of coal fly ash”. (I’m not sure whether the ‘average composition’ method they’ve used really debunks the criticism though?)
Loeb also mentions that the team are already planning a new expedition in 2025, hoping to find “large pieces from its wreckage” which would “allow us to determine its age from its radioactive isotopes, to find the composition of volatile elements that were lost from the spherules we retrieved, and also to gauge its material strength and thermal properties, potentially explaining why it maintained its integrity despite witnessing atmospheric stress beyond the tolerance of the toughest iron meteorites known in the solar system.”
It’s interesting to note the language used by Loeb, in describing it as “wreckage” – which is suggestive of a vehicle or at least something artificial. Loeb has certainly not shied away from implying/hyping the idea that alien spaceships have visited Earth or our solar system in the past, so I wouldn’t take it too seriously.
In any case, to find any larger pieces of the wreckage/debris his team intends to use a remotely operated vehicle with a video feed that would allow them to view the materials being picked up. It will be interesting to see how the 2025 expedition fares.