On one hand, the speed of light is just a number: 299,792,458 meters per second. And on the other, it’s one of the most important constants that appears in nature and defines the relationship of ...

James is a published author with multiple pop-history and science books to his name. He specializes in history, space, strange science, and anything out of the ordinary.View full profile James is a ...

The universe has a speed limit, and it's the speed of light. Nothing can travel faster than light — not even our best spacecraft — according to the laws of physics. So, what is the speed of light?

In 1887, one of the most important experiments in the history of physics took place. American scientists Michelson and Morley failed to measure the speed of Earth by comparing the speed of light in ...

Everyone knows the number for the speed of light — but almost nobody knows the uncomfortable truth behind it. Measuring light in one direction requires perfectly synchronized clocks, and that’s the ...

Astronomers have managed to measure the spin of a supermassive black hole, which could help reveal how they grew in the universe. Reading time 4 minutes A team of astronomers has managed to calculate ...

Every high school physics student knows c, or the speed of light, it’s 3 x 10^8 metres per second. More advanced or more curious students will know that this is an approximation, and the figure of 299 ...

The principle of relativity, as initially described by Galileo, posits that the laws of physics remain consistent regardless of an observer's relative motion. Einstein's special relativity ...