¿Qué es un año luz?

The video explains how light travels at 3,000,000,000 meters per second and why astronomers use light-years to measure vast distances in space. It highlights that light takes 8.3 minutes to travel from the Sun to Earth, meaning we see events after they occur. The closest star, Proxima Centauri, is 4.2 light-years away, so its light takes 4.2 years to reach us. This illustrates how observing space is like looking back in time due to the immense distances involved.

What new insight or understanding did you gain from this video?