UFO sightings recorded at RAF Coningsby and over the Wolds are among those in secret files revealed for the first time today, Wednesday, by the Ministry of Defence.
The files cover UFO sightings recorded between 1978 and 2002 and can now be downloaded from the National Archives website.
A record from December 1981 describes a "medium bright red light descending to ground level and turning white."
It was seen from a runway at the RAF base and was thought to be between six and ten miles away.
Another report, possibly from the same night, gives an account of a "bright light from a globe-like object described as a floodlight in the sky."
It was seen by a woman driving north from Tetford to Scamblesby and then Goulceby.
She said the light was mostly overhead and it was so bright she would not have needed to use her headlights.
The report says: "When driver took a wrong turn she lost the light but having turned around she found it awaiting her further on like a bright globe with a beam of light."
The woman was very frightened and did not want any publicity.
Her husband, who was at home, also saw the light as he met her.
An MOD memo from 1983 included in the files states: "The Ministry of Defence does not deny there are strange things to see in the sky.
"It believes, however, that there are adequate material explanations for these - satellite debris re-entering the earth's atmosphere, ball lightning, unusual cloud formations, meteorological balloons, aircraft lights, aircraft at unusual angles etc. It certainly has no evidence that alien spacecraft have landed on this planet."
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