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 ...

(via PBS Space Time) One of the most fundamental physics facts is that the speed of light in a vacuum is constant for all observers. But can we really be sure that the speed of light wasn’t different ...

Einstein’s claim that the speed of light is constant has survived more than a century of scrutiny—but scientists are still ...

National Aeronautics and Space Administration (NASA) will show you what it is like to travel to the speed of light using a short animation video. If you're interested in science fiction, you might ...

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 the Earth by comparing the speed of light in ...