A light-year is defined as the measurement of length or the distance light travels in a vacuum in a year. One light-year is close to 6 trillion miles.
Example of a light-year
- Reflected sunlight travelling from the moon’s surface takes 4.04 × 10-8 light-years to reach the earth.
- It takes 1.58 × 10-5 light-years for light from the Sun to reach the earth.