Thanks to Einstein's theory of relativity, numerous tests have concluded tangible effects on how we on Earth record and ...

A spacecraft traveling at 99 percent the speed of light toward Alpha Centauri would cross 4.3 light-years in what feels like months to its crew, while decades tick by on Earth. That asymmetry is not ...

Tracking time is one of those things that seems easy, until you really start to get into the details of what time actually is. We define a second as 9,192,631,770 oscillations of a cesium atom.

A new study from the National Institute of Standards and Technology, or NIST, has revealed how time flows on Mars, and exactly how out of sync it is compared to our flow of time here on Earth.