Asked by: Pete Groves, London
That's what Einstein asked himself as a schoolboy and it led him to his famous Special Theory of Relativity. Its equations show that objects look increasingly distorted as the speed of travel increases, with the view ahead becoming progressively brighter. Then truly bizarre effects start to kick in, with objects far ahead apparently moving further away, while those behind come into view.
Eventually, at lightspeed there's nothing but a dazzingly bright spot of light surrounded by complete blackness. Weird!
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