Asked by: Tony Sutcliffe, Leeds
Every so often rumours circulate on the internet about the reappearance of a ‘wandering planet’ called Niburu. It’s supposedly mentioned on ancient Sumerian clay tablets and is said to have crashed through the early Solar System creating the asteroid belt and the Earth before vanishing again. It’s true that beyond the Solar System lurk failed stars known as brown dwarfs that are barely bigger than the planet Jupiter. However, the chances of a disastrous encounter with one are mercifully small.
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