A light-year is a unit of distance, not time. It represents the distance that light travels in one year. Since light travels at a speed of approximately 299,792,458 meters per second in a vacuum, we can calculate the length of a light-year in terms of meters:
1 light-year = 299,792,458 meters per second × 60 seconds per minute × 60 minutes per hour × 24 hours per day × 365.25 days per year
Performing the calculation, we find that:
1 light-year ≈ 9,461,000,000,000 kilometers or about 5,878,625,000,000 miles.
So, a light-year is a distance of approximately 9.461 trillion kilometers or 5.878 trillion miles.