A light year is the distance traveled by a light in a vacuum within a Julian year (365.25 days.) A light year can also be described as an astronomical unit of measuring astronomical distances in space.
Even though humans have been studying the heavens for many centuries, we still know very little about the processes and objects in the space. We learn more and more about the galaxies, planets, and stars as we continue to explore.
Exoplanets, also called “extrasolar planets” are worlds orbiting other stars. Thousands of possible exoplanets have been found through ground-based and space-based observatories.