A combined historical and scientific approach is applied to ancient reports of what might today be called unidentified flying objects (UFOs). Many conventionally explicable phenomena can be weeded out, leaving a small residue of puzzling reports. These fall neatly into the same categories as modern UFO Sightings reports, suggesting that the UFO phenomenon, whatever it may be due to, has not changed much over two millennium. credit Earl M Digby
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**Includes accounts dating back to 250BC!** PUBS.GISS.NASA.GOV