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 ...

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 ...

Nothing can travel faster than light — in a vacuum. But when light slows down, sometimes matter can blaze past that speed limit, creating a stunning glow called Cherenkov radiation. We can see ...

In those observations, the stream was flying past at only four times the speed of light. That still didn’t seem right. Nothing in the universe can go faster than the speed of light. As it ...

But in Earth-bound reality, traveling at the speed of light (299,792,458 meters per second, or 670,616,629 miles per hour, in a vacuum) in a clunky rocket is a physical impossibility.

These are the words that introduce every episode of classic "Star Trek," the show that essentially popularized the concept of traveling the stars at the speed of light – or faster. While "Star ...

Lidar is an acronym that stands for "light detection and ranging." It's basically like a tape measure—except that it uses the speed of light to measure distance, instead of a physical object.

Everyone measuring the speed of light will get the same result, no matter where they are or how fast they are moving. Let’s say you’re in the car driving at 60 miles per hour and your friend ...

But we’ll give you the short version here. Light travels about a foot in a nanosecond. What have you got that measures signals on a nanosecond scale pretty reliably? Of course, it’s your ...

As I watched shooting stars from our campsite in the Virgin River Canyon south of St. George, Utah, I could not get my mind around an endless universe. How can something go on forever? I am used ...