Are you fast? Can you beat a friend in a race? How about an olympic sprinter? How about a beam of light? Find out how fast light is, how far a light year is, and learn how close our nearest exoplanet ...

Einstein’s claim that the speed of light is constant has survived more than a century of scrutiny—but scientists are still daring to test it. Some theories of quantum gravity suggest light might ...

Scientists captured the first images of the Terrell-Penrose effect, showing objects near light speed appear rotated rather than compressed in photos.

If there is an absolute law in the universe, it’s that nothing can travel faster than the speed of light. For science-fiction enthusiasts, that’s a bit depressing. Space is big, and while the speed of ...