The speed of light is a fundamental constant, approximately 299,792,458 meters per second. It's the same for all observers and hasn't changed measurably over billions of years. Nothing can travel ...

So, you’re driving a car at half the speed of light. (Both hands on the wheel, please.) You turn on the headlights. How fast would you see this light traveling? What about a person standing by the ...

Light is faster than anything else in the known universe, though its speed can change depending on what it's passing through. When you purchase through links on our site, we may earn an affiliate ...

In 1676, by studying the motion of Jupiter's moon Io, Danish astronomer Ole Rømer calculated that light travels at a finite speed. Two years later, building on data gathered by Rømer, Dutch ...

Einstein’s famous equation states that energy (E) equals mass (m) times the speed of light squared (c 2); the speed of light (c) is a universal physical constant exactly equal to 299,792,458 meters ...

Breakthroughs, discoveries, and DIY tips sent every weekday. Terms of Service and Privacy Policy. Back in 2018, astronomers examining the ruins of two collided ...

According Einstein's Theory of Relativity, the speed of light operates as a universal speed limit on anything with mass. When you purchase through links on our site, we may earn an affiliate ...

The constancy of the speed of light is a pillar of modern physics, but questions persist about its absolute universality.

We throw around terms like “light year” and “faster than light travel” frequently. But to really understand the scale it helps to feel how fast the speed of light is. The flight simulation video below ...

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 ...

Here, a calcite crystal is struck with a laser operating at 445 nanometers, fluorescing and displaying properties of birefringence. Unlike the standard picture of light breaking into individual ...