Critique of arXiv submission 2308.15623, "Discovery of Spherules of Likely Extrasolar Composition in the Pacific Ocean Site of the CNEOS 2014-01-08 (IM1) Bolide", by A. Loeb et al

TL;DR

This paper critically examines a preprint claiming interstellar origin of certain spherules linked to a 2014 bolide, demonstrating that the evidence supports a Solar System origin and highlighting flaws in the original claims.

Contribution

It provides a detailed critique of the original manuscript, refuting its claims of interstellar origin and presenting alternative explanations consistent with known terrestrial processes.

Findings

Fe isotopic ratios indicate Solar System origin with >99.995% probability.

Chemical signatures are consistent with terrestrial contamination and oceanic processes.

No statistical correlation between spherules and the 2014 bolide evidence.

Abstract

Recently a manuscript by Loeb et al. was uploaded to arXiv (preprint 2308.15623) that asserted that the CNEOS bolide 2014-01-08 was interstellar; that spherules recovered from the seafloor near the airburst were associated with this bolide; that they had Fe isotopic ratios indicating origin as micrometeorites; that they had unusual chemical compositions enriched in Be, La and U, never seen before in micrometeorite spherules; that these compositions were formed in the magma ocean stage of a differentiated extrasolar planet; and that the Be abundance reflected passage through the interstellar medium. Despite not being peer-reviewed, this uploaded manuscript has been reported by media outlets as "published", and its conclusions have been widely distributed as fact. The purpose of this manuscript is to provide potential peer reviewers and the general public with an appreciation of the multiple fatal flaws with the manuscript's arguments. We discuss the published evidence that the 2014-01-08 bolide is not interstellar. We show that there is no statistical spatial correlation of a chemical signature or even number of recovered spherules with the 2014-01-08 bolide. We demonstrate that the Fe isotopic ratios decisively indicate an origin in our Solar System, with > 99.995% probability. We demonstrate that the unusual enrichments in La, U, etc., have in fact been observed in micrometeorites before and attributed to terrestrial contamination; and that the Be abundances are similarly consistent with those of ferromanganese nodules, after reacting with sea water. Far from being exotic particles from an extrasolar planet, the spherules collected and analyzed by Loeb et al. appear to be just like those found around the world, with a Solar System origin and compositions modified by tens of thousands of years residence at the ocean bottom.