We humans love things we can’t explain. Witness the vast array of outlandish claims made about Stonehenge, from ancient calendar to alien stargate, when in all likelihood it was just a big clock or an early marketplace, a neolithic branch of Tesco.
When the unknown is also alien, the mystery only grows more magnetic. Think of that iconic opening to Stanley Kubrick’s 2001: A Space Odyssey: a family of apes wake one morning to find a black monolith looming over them; that had its origins in Arthur C Clarke’s short story The Sentinel. Did some super-advanced civilisation intercede in the early evolution of intelligent life on earth? Or was the monolith just filming a very special edition of Life on Earth?
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