A light-year, alternatively spelled light year (ly or lyr[3]), is a unit of length used to express astronomical distances and is equal to exactly 9 460 730 472 580.8 km, which is …

A light-year is the distance light can travel in one year. Light is the fastest thing in our Universe traveling through interstellar space at 186,000 miles/second (300,000 km/sec).

Jan 1, 2025 · Multiply the number of seconds in one year by the number of miles or kilometers that light travels in one second, and there you have it: one light-year. It’s about 5.9 trillion miles …

Sep 25, 2025 · A light-year is the distance light travels in one Earth year. Learn about how we use light-years to measure the distance of objects in space.

Dec 13, 2025 · light-year, in astronomy, the distance traveled by light moving in a vacuum in the course of one year, at its accepted velocity of 299,792,458 metres per second (186,282 miles …

How many miles are in a light year? Use this easy and mobile-friendly calculator to convert between light years and miles. Just type the number of light years into the box and hit the …

Dec 15, 2024 · What Is a Light-Year? A light-year is the distance light travels in one year. Light moves incredibly fast — about 186,000 miles (300,000 kilometers) per second, covering 5.88 …

Light-year (9,460,731,000,000,000 meters) The light-year is a unit of length used to express astronomical distances and measures about 9.5 trillion kilometres or 5.9 trillion miles.

Learn how to convert miles to light years with a simple formula. Includes real examples, cosmic scale comparisons, and FAQs for astronomy fans.

May 3, 2025 · Light Years and Human Perspective In everyday life, we measure distance in meters, kilometers, or miles. These units make sense when dealing with cities, countries, or …