When you consider the distance Santa must travel on Christmas Eve to reach the homes of all the good children in the world, he would have to travel close to the speed of light. But he may have found a way around the problem by warping the space around the sleigh.
Travelling from the North Pole all around the world in one night means that the reindeer must accelerate Santa, his sleigh and all the presents up to roughly 10 million kilometres per hour, or .97 per cent of the speed of light. At that speed, air friction from the un-aerodynamic shape of the reindeer, with their antlers and legs sticking out, plus the odd-shaped presents stacked on top of the sleigh, would produce ultra-high temperatures that would incinerate Santa and his entire transport system in a matter of seconds. He would instantly become a bright meteor in the sky.
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