And that is absolutely 100% accurate, with no measurement errors. But Jack, I hear you say, what are you talking about? The reason we know that that's exactly the speed of light, is that we defined it ...

No matter how fast you move, the light will always catch you. Nowadays we take the speed of light for granted. It's a fundamental constant of the universe: light simply travels at the speed it does ...

Researchers have developed a technique for measuring speed and distance in indoor environments, which could be used to improve navigation technologies for robots, drones -- or pedestrians trying to ...

Learn how to calculate when and where two trains will meet! This video walks you through the process of using relative speed and distance to find the exact point and time of intersection. Perfect for ...

Scientists have demonstrated the fastest distance measurement so far. The researchers demonstrated on-the-fly sampling of a gun bullet profile with micrometer accuracy. The experiment relied on a ...

Observational clues The transit of Venus allows a geometrical measurement of the Earth–Sun distance, and a measurement of the speed of light. (Courtesy: iStock/milehightraveler) Light is so ...