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Our Moon. It lights up our nights, governs our tides and has inspired millions — perhaps billions -– of people throughout history to contemplate its nature, its influence on our lives (if any) and, of course, where it may have come from.

The currently accepted theory is that over four and a half billion years ago our newly-formed planet was impacted by a Mars-sized body, a catastrophic collision that flung molten bits of Earth’s mantle into space and created a ring of debris. This gradually gathered together to create our Moon… but, according to some new models created by researchers at UC Santa Cruz, it may have actually created two moons. But if this is indeed the case, what happened to the other one?

Read more on my article at Discovery News.