Sediment layers dated near the Younger Dryas onset at multiple North American sites contain platinum enrichments substantially above local background.

Real ICP-MS measurements, but single-group, CRG-affiliated, sampled around pre-identified horizons without background characterization, and never independently replicated.

Platinum enrichments at North American sites are provisionally supported. Proponent measurements indicate elevated levels, but their extraordinariness is unquantified due to targeted sampling rather than continuous background measurements. The strongest opposing consideration is that the study's authors formally corrected the paper to withdraw the extraterrestrial-source conclusion, acknowledging the enrichments could merely reflect a distributed influx of unresolved, potentially terrestrial material.

Moore et al. (2017) report boundary‑age sedimentary Pt enrichments at eleven North American sites, with boundary concentrations roughly an order of magnitude above local background (YDIH‑E002), and these measurements were not themselves challenged in the 2026 correction. Still, they come from a single proponent‑affiliated group, with sampling targeted at pre‑identified horizons and without continuous background characterization, leaving open questions about how rare such peaks truly are. The strongest opposing consideration is the absence of independent‑lab replication with more neutral sampling designs, coupled with osmium‑isotope evidence at other sites that shows Pt‑group anomalies can be volcanic, undermining any default assumption that the observed enrichments must be impact‑derived.

Moore and colleagues reported fire-assay and ICP-MS platinum at eleven North American sites averaging about twelve times local background near strata dated to the onset, and the 2026 correction leaves those enrichments standing while withdrawing the extraterrestrial-source conclusion. The measurements are real but come from a single affiliated group sampling around pre-identified horizons without systematic above-and-below background control or independent-laboratory replication. The strongest opposing consideration is that a continentally distributed platinum influx would be an important observation if independently replicated with continuous sampling. Targeted sampling cannot by itself establish that the peaks are extraordinary.

Eleven-site ICP-MS and fire-assay measurements published in Scientific Reports, left standing by the authors' own 2026 correction, which withdrew only the extraterrestrial-source conclusion. But the measurements come from a single proponent-affiliated group, sampled around horizons pre-identified as the boundary, with no continuous background sampling and no independent-laboratory replication of these specific aliquots. Strongest opposing consideration: "twelve times background" under targeted sampling measures the sampling design as much as the sediment — without background profiling, the peaks' extraordinariness is unquantified; independent replication with continuous above-and-below sampling could upgrade or deflate this claim quickly.

The fire-assay and ICP-MS numbers at eleven sites are real analytical results and the 2026 correction left the measurements untouched while withdrawing only the source attribution. But they come from a single proponent-affiliated group with no independent-laboratory replication, and the sampling targeted horizons pre-identified as the boundary, so the "twelve times background" ratio partly measures the sampling design rather than the sediment. The strongest opposing consideration in favor of the claim is that the enrichments were reported across a wide geographic spread and the authors' own correction did not retreat from them. Continuous stratigraphic sampling and outside replication would settle it quickly.

Real ICP-MS measurements (YDIH-E002), but single-group, CRG-affiliated, sampled around pre-identified horizons without background characterization, and never independently replicated; the 2026 correction decouples them from any extraterrestrial conclusion.

Real fire-assay and ICP-MS enrichments (YDIH-E002), but from a single CRG-affiliated group sampling around pre-identified horizons without continuous background characterization, and never independently replicated. The May 2026 correction leaves the measurements intact while decoupling them from any extraterrestrial inference.

Real fire-assay and ICP-MS enrichments (YDIH-E002), but from a single CRG-affiliated group sampling around pre-identified horizons without continuous background characterization, and never independently replicated. The May 2026 correction leaves the measurements intact while decoupling them from any extraterrestrial inference.

Real fire-assay and ICP-MS enrichments (YDIH-E002), but from a single CRG-affiliated group sampling around pre-identified horizons without continuous background characterization, and never independently replicated. The May 2026 correction leaves the measurements intact while decoupling them from any extraterrestrial inference.

Real fire-assay and ICP-MS enrichments (YDIH-E002), but from a single CRG-affiliated group sampling around pre-identified horizons without continuous background characterization, and never independently replicated. The May 2026 correction leaves the measurements intact while decoupling them from any extraterrestrial inference.

Real fire-assay and ICP-MS enrichments (YDIH-E002), but from a single CRG-affiliated group sampling around pre-identified horizons without continuous background characterization, and never independently replicated. The May 2026 correction leaves the measurements intact while decoupling them from any extraterrestrial inference.

Real ICP-MS measurements published in Scientific Reports, but from a single research group with Comet Research Group affiliations, sampled around horizons pre-identified as the boundary, and without the systematic above-and-below sampling needed to establish how often such peaks occur by chance. The 2026 correction leaves the enrichments standing while withdrawing the source attribution.

Elevated platinum concentrations averaging roughly 12 times local background were measured across 11 sedimentary sites in six U.S. states. While the physical measurements themselves remain unchallenged, the sampling was targeted specifically at putative boundary layers rather than continuous stratigraphic profiles. The strongest opposing consideration is that all measurements were produced by a single proponent research group without independent laboratory replication, and the authors formally withdrew their extraterrestrial attribution in 2026.

The Moore et al. 2017 measurements are real and were not challenged by the 2026 correction, which withdrew only the source conclusion. The strongest opposing consideration is structural: the work is proponent-affiliated, sampled around pre-identified horizons without continuous background sampling (so the peaks' extraordinariness is unquantified), and has no independent-laboratory replication — and the pattern of the Baffin Bay retraction shows exactly this design failing under scrutiny.

YDIH-E002 reports platinum peaks at eleven sites in six states, averaging substantially above targeted above-and-below background, and the 2026 correction did not withdraw those measurements. The evidence comes from one proponent-affiliated team using pre-identified horizons without comprehensive continuous-background sampling, so independent reproducibility and extraordinariness remain uncertain. The strongest opposing consideration is precisely that lack of independent laboratory replication, although it does not amount to a direct refutation of the reported measurements.

Fire-assay and ICP-MS data at eleven North American sites report platinum peaks averaging roughly twelve times local background near strata assigned to the Younger Dryas onset. Strongest opposing consideration is the absence of independent-laboratory replication, targeted rather than continuous sampling, and the authors' own 2026 correction withdrawing any extraterrestrial-source claim.

Moore et al. 2017 report boundary-layer platinum averaging 6.0 ppb (range 0.3–65.6) against ~0.3 ppb above and below at 11 sites in six states (E002). The 2026 correction withdrew the attribution and left the measurements unchallenged (E003). Independent highly-siderophile-element work at Hall's Cave and Page-Ladson treats Younger Dryas-age geochemical anomalies in North American sediments as real while assigning them volcanic origins (E004, E029); this is partial corroboration inferred from those records, not a re-measurement of Moore's sites. Strongest opposing consideration: all eleven sites come from one proponent-affiliated group with no independent replication, and sampling targeted pre-identified horizons without continuous background, so "substantially above local background" rests on a few adjacent samples. "Dated near the Younger Dryas onset" also inherits the chronology weaknesses of C010.

Real ICP-MS measurements published in Scientific Reports, but from a single research group with Comet Research Group affiliations, sampled around horizons pre-identified as the boundary, and without the systematic above-and-below sampling needed to establish how often such peaks occur by chance. The 2026 correction leaves the enrichments standing while withdrawing the source attribution.