On June 24, 1947, businessman and private pilot Kenneth Arnold reported seeing nine unidentified aerial objects while flying near Mount Rainier, Washington. Arnold described the objects as crescent-shaped and highly reflective, moving at what he estimated to be extraordinary speeds. He later gave a detailed account to authorities and the press, and his description — coupled with a colorful headline in the East Coast media — is widely credited with introducing the term "flying saucer" into the American vocabulary. Sequence of events - Morning flight: Arnold was flying a small aircraft on a commercial trip from Chehalis, Washington, to Yakima when he observed the objects about 9:30 a.m. He reported seeing them at a distance, tracking from left to right as they passed near Mount Rainier. - Observation and report: Arnold timed the objects’ passage relative to known landmarks and estimated their speed as many times faster than typical aircraft of the era. He landed in Yakima and reported his sighting to local officials and later to the press and the U.S. Army Air Forces, which was then investigating postwar airspace security. - Media reaction: News wires picked up Arnold’s account; one early newspaper headline described "flying saucers," a phrase that stuck despite Arnold’s own description being more like crescent or boomerang shapes. The story spread rapidly across the country and prompted additional reports of similar sightings. Impact and context Arnold’s report occurred in a postwar environment marked by rapid aviation advances, public interest in space and technology, and Cold War anxieties. The U.S. military investigated many such reports; the Army Air Forces examined Arnold’s account and continued to collect reports of unidentified aerial phenomena. Arnold’s sighting stimulated a surge of civilian sightings and press coverage, contributing to a nascent public belief that unknown craft might be operating in U.S. airspace. What is known and what remains disputed - Known: Kenneth Arnold filed contemporaneous accounts with authorities and spoke to multiple reporters in the days following the sighting. His descriptions and estimations of speed and maneuverability are documented in primary press reports and agency files from 1947. The rapid spread of the story and its role in popularizing the term "flying saucer" are well attested in newspaper archives. - Disputed or uncertain: Explanations for what Arnold saw remain contested. Proposed interpretations have ranged from optical illusions, mirages, or misidentified conventional aircraft or natural phenomena, to outright fabrication. No consensus has been reached establishing a definitive physical explanation for the objects Arnold described. Legacy Arnold’s June 24, 1947, report is commonly regarded by historians of the phenomenon as a turning point that moved reports of unidentified aerial sightings from localized incidents to a national cultural topic. It stimulated further reporting, government interest, and, in subsequent years, formal investigations of unidentified aerial phenomena. The episode also illustrates how a single well-publicized account can shape public perception and language around uncertain events. Sources and evidence This summary is based on contemporaneous newspaper accounts, public statements by Kenneth Arnold, and later historical research into early postwar UFO reporting and government records. Where interpretations differ, this text notes disputes rather than asserting unverified conclusions.