Add Yahoo as a preferred source to see more of our stories on Google. Anything with mass cannot reach lightspeed. In science fiction, spaceships moving at or beyond lightspeed enable all manner of ...

paceships zipping at the speed of light or faster are a staple of science fiction. Think of the Millennium Falcon in the "Star Wars" movies and the starship Enterprise in "Star Trek." Such travel ...

Explores why traveling at light speed defies physics, highlighting limits of relativity, energy requirements, and the fundamental barriers that make faster-than-light travel impossible. What we know ...