I’ve calculated Santa’s speed on Christmas Eve – and this is what it would do to Rudolph’s nose

Tayla Walsh/Pexels

With billions of children around the world anxiously waiting for their presents, Father Christmas (or Santa) and his reindeer must be travelling at breakneck speeds to deliver them all in one night.

But did you know that light from an object travelling at high speeds changes colour? This is thanks to what’s called the Doppler effect – the way speed affects the length of waves, such as sound or light.