 Astronomer Hugh Ernest Butler observed similar craters and said they were likely caused by lightning strikes.In the 1960s, in Tully, Queensland, Australia, and in Canada, there were many reports of UFO sightings and circular formations in swamp reeds and sugar cane fields.For example, on 8 August 1967, three circles were found in a field in Duhamel, Alberta, Canada; Department of National Defence investigators concluded that it was artificial but couldn't say who made them or how.