Wikimedia CommonsCool Facts
Unbelievably fast. Light zooms at 299,792,458 meters per second. To put that in perspective, light could circle Earth seven times in just one second.
Defines a meter. Scientists actually use the speed of light to define what a meter is. One meter is the distance light travels in vacuum during 1/299,792,458 of a second.
Nothing faster exists. Nothing in the universe can travel faster than light. Even the speediest rockets are slow turtles compared to light's incredible pace.
About a billion kilometers per hour. The speed of light equals roughly 1 billion kilometers per hour, which is the same as 700 million miles per hour. That's way faster than any spacecraft humans have ever built.
Always the same. No matter who measures it or where they measure it, light always travels at exactly this same speed in empty space. It's one of the most dependable laws of nature.
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