On 9 December 1965 a bright fireball crossed several states, and in the woods outside this Pennsylvania village, according to the people who live there, something came down. Witnesses described an object the size of a car, shaped like an acorn, with a band of markings around its base. By evening the military had cordoned the woods off; by morning they announced they had found nothing. The official answer is a meteor, and astronomers did track that fireball from Ontario into Pennsylvania. A meteor does not explain a cordon. In 2005 NASA acknowledged that its files on the episode were missing. A replica of the acorn has stood in the village since the 1990s — put up for a television programme, and never taken down.

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Giant Rock and the Contactee Conventions

A free-standing granite boulder in the Mojave — by some counts the largest in the world, about seven storeys high. From 1947 a former aircraft engineer named George Van Tassel lived beside it, having built a café and an airstrip under the rock. Van Tassel said that in 1953 visitors from Venus arrived and dictated the design of a machine for rejuvenation. He built it seven kilometres away — the wooden dome called the Integratron, which is still standing. From 1954 to 1978 he held annual contactee conventions at the rock; in the best years up to eleven thousand people came. In 2000 a third of the rock split off.