query: When did the first episode of the TV show UFO air?
passage: UFO (TV series)
UFO is a 1970 British science fiction television series about an alien invasion of Earth. It was created by Gerry Anderson and Sylvia Anderson with Reg Hill, and produced by the Andersons and Lew Grade's Century 21 Productions for Grade's ITC Entertainment company.
passage: Kenneth Arnold UFO sighting
The Kenneth Arnold UFO sighting occurred on June 24, 1947, when private pilot Kenneth Arnold claimed that he saw a string of nine, shiny unidentified flying objects flying past Mount Rainier at speeds that Arnold estimated at a minimum of 1,200 miles an hour (1,932 km/hr). This was the first post-War sighting in the United States that garnered nationwide news coverage and is credited with being the first of the modern era of UFO sightings, including numerous reported sightings over the next two to three weeks. Arnold's description of the objects also led to the press quickly coining the terms "flying saucer" and "flying disc" as popular descriptive terms for UFOs.