Here's why:

* Distance: The Earth is about 93 million miles (150 million kilometers) from the Sun.

* Speed of Light: Light travels at the fastest speed possible, approximately 186,282 miles per second (299,792 kilometers per second).

* Light Travel Time: It takes light about 8 minutes and 20 seconds to travel from the Sun to Earth.

So, instead of years, we measure the time it takes for light to travel from the Sun to Earth.