دليل علمي
On 23 January 1974 on the Berwyn Mountains in Llandrillo, Merionethshire, Wales, lights and noises were observed that were alleged to be related to a UFO sighting on Cadair Berwyn and Cadair Bronwen. Scientific evidence indicated that the event was generated by an earthquake combined with sightings of a bright meteor widely observed over Wales and northern England at the time.