By Matthew Allen
What’s the fastest thing you can think of? A Cheetah? A Formula 1 car? A space rocket? Well, there’s one thing which is faster than all of these and is in fact the fastest thing in the Universe: Light! It was in 1676 that the Danish astronomer Ole Rømer first measured the speed of light.
Image from Google Doodle of the day, marking 340 since the determination of the speed of light.
When we talk about light and the speed of light, we are talking about the light you see with your eyes, such as from a light bulb or the Sun. But, we’re also talking about the different types of light that you can’t see with your eyes, such as X-Rays, Infrared and Radio waves. They’re all different types of light and they all travel at the same speed: 300 million metres per second!
It’s because light travels at a finite speed (as opposed to an infinite speed) that means it takes around 8.5 minutes for light from the Sun to reach us down here on Earth. If the Sun suddenly disappeared this second, then we would still be able to see it and the light ...