* Our nearest star: Proxima Centauri is the closest star to our Sun, about 4.24 light-years away.

* The speed of light: Light travels at approximately 299,792,458 meters per second (186,282 miles per second).

* Time to travel: Since a light-year is the distance light travels in one year, it would take 4.24 years to reach Proxima Centauri if you could travel at the speed of light.

Important Note: Currently, it's impossible for anything with mass to reach the speed of light. This is a fundamental principle of physics.