Documents / Report
This synopsis was prepared by Oak Ridge National Laboratory for the All-domain Anomaly Resolution Office (AARO). It reports on an analysis of drill shavings and a small bulk piece from a metallic specimen claimed to be linked to an unidentified phenomenon over central Ohio around 1995. Chemical assays, microscopy, computed tomography and gamma spectroscopy showed a conventional near-eutectic aluminum-silicon casting alloy that had cooled slowly and gave off no radiation. The report concludes the specimen is ordinary terrestrial industrial metal with no evidence of exotic origin.
Synopsis: Analysis of a Aluminum Specimen2 1. Overview AARO is congressionally mandated to investigate unidentified anomalous phenomena (UAP) incidents and publicly report its findings. AARO sponsored a series of measurements on a metallic alloy composed of primarily aluminum and silicon, claimed to have association with a UAP in or around 1995 and further asserted to have nonstandard composition. AARO secured science and technology partner ORNL, one of 17 US Department of Energy National Laboratories, to independently assess and perform thorough char‑ acterization studies on samples from the specimen, leveraging ORNL’s 80-year history of world-leading materials science expertise. Figure 1. Photographs of the received samples. (Left) Metal shavings in their transfer vials. (Above) The main mass material. The central charge to ORNL was to investigate (1) the composition of the metal, (2) whether the chem‑ istry or structure is anomalous, and (3) whether it emits a gamma-ray signal. Drawing on established, peer‑reviewed methods and side‑by‑side quality controls, ORNL found that the sample is a conventional near‑eutectic aluminum–silicon alloy near the Al–Si eutectic composition. A eutectic composition is an alloy that melts at a lower temperature than either of its individual compo‑ nents and typically exhibits superior castability and fluidity, making such alloys preferred for manufac‑ turing applications where shaping of parts is critical. Eutectic compositions are thus well understood and common in manufacturing—details are documented on phase diagrams that show where an alloy in liquid form transforms into separate solid phases simultaneously upon cooling. Specifically, the sam‑ ple in question can be best described as a eutectic aluminum–silicon alloy nearly, though not perfectly, matching American Society for Testing and Materials (ASTM) designations A413.1/369.1. In addition to finding no evidence of unusual elements or chemistries that would imply novel mecha‑ nisms, ORNL found no evidence of rapid cooling or gamma emission. The use of multiple, independent methods (with calibration against recognized standards) reduces the chance of a systematic error and increases confidence that these samples are representative of the source part. Additional pieces from different locations of the original component, or access to manufac‑ turing records, could narrow the identification to a specific catalog grade and heat treatment, but such data are not necessary to support the central findings reported here, which indicate no behaviors incon‑ sistent with ordinary cast aluminum.
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Report, from the aaro collection. The PDF is mirrored here; the original link is above. 10 pages are in the text index: search them above, or from the library's search.