1947: Kenneth Arnold and the flying saucers
How nine shiny objects and one newspaper headline named a whole subject.
How this site works. Every fact is in our own words with its source linked beside it. The pictures are our own drawings. We never say aliens have been found, because nobody has shown that they have; we show what was reported, then what the evidence says.
On 24 June 1947, private pilot Kenneth Arnold was flying past Mount Rainier in Washington State, USA. Smithsonian Air and Space
Arnold was an experienced pilot with 4,000 flying hours and a member of an Idaho search and rescue unit. Smithsonian Air and Space
He was making a detour to look for a crashed US Marine Corps transport plane, hoping to claim a $5,000 reward. Smithsonian Air and Space
What he said he saw
Shortly before 3 p.m. he saw a bright flash and at first assumed it was sunlight glinting off a military plane. Smithsonian Air and Space
He said the flashes came from nine shiny objects flying in a formation about five miles long, each about 100 feet across with no tail he could see. Smithsonian Air and Space
He said they moved like a saucer skipping on water. The National Archives
He timed them flying from Mount Rainier to Mount Adams and worked out a speed of about 1,200 mph; some accounts say 1,700 mph. Smithsonian Air and Space
How fast?
He timed them flying from Mount Rainier to Mount Adams and worked out a speed of about 1,200 mph; some accounts say 1,700 mph. Smithsonian Air and Space
Britannica says Arnold estimated their speed at several thousand miles per hour, and calls the objects crescent-shaped. Britannica
Judging speed against an empty sky is famously hard; see the explanations page.
How “flying saucers” got their name
A newspaper report then wrongly said the objects were saucer-shaped, which is how we got the phrase “flying saucer”. Britannica
Arnold strongly denied first calling them “flying saucers”, though stories at the time say he used the words saucer, disc and pie-pan. Smithsonian Air and Space
A reporter’s story for the Associated Press described “nine bright saucer-like objects”, and by that afternoon “flying saucers” had spread across the United States. Smithsonian Air and Space
In a report he sent to the US Air Force that July, Arnold drew a shape rather like the heel of a shoe, not a round saucer. Smithsonian Air and Space
The National Archives calls Arnold’s sighting the first report of “flying saucers”. The National Archives
What happened next
Arnold’s sighting kicked off a craze, and hundreds of UFO sightings began pouring in. Smithsonian, Roswell
As reports grew, the US Air Force began an investigation called Project Sign in 1948. Britannica
What is known
The Smithsonian says nobody will ever know exactly what Arnold saw, and that it remains unexplained. Smithsonian Air and Space
Judging the distance and speed of a light in a blank sky is very unreliable, because there is nothing to compare it with. Britannica
The Smithsonian’s air and space museum urges everyone looking at the sky to use critical thinking about whatever they see. Smithsonian Air and Space
Our view: the most famous UFO shape in the world comes from a misunderstanding. Arnold described how the objects moved, and the world heard what they looked like. Every UFO story is worth reading twice for exactly that reason.
Next: the Roswell file →