Light-year - Wikipedia
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 approximately 9.46 trillion km or …
How far is a light-year? Plus, distances in space - EarthSky
Jan 1, 2025 · Light is the fastest-moving stuff in our universe. It travels at 186,000 miles per second (300,000 km/sec). So, a light-year is 5.88 trillion miles (9.46 trillion km). However, stars and nebulae...
How Far is a Light Year? | The Fastest Thing in the Universe
Light is the fastest thing in our Universe traveling through interstellar space at 186,000 miles/second (300,000 km/sec). In one year, light can travel 5.88 trillion miles (9.46 trillion km). A light year is a …
What Is a Light-Year? | NASA Space Place – NASA Science for Kids
Sep 25, 2025 · One light-year is about 6 trillion miles (9 trillion km). That is a 6 with 12 zeros behind it! When we use powerful telescopes to look at distant objects in space, we are actually looking back in …
Light-year | Distance, Measurement, Time | Britannica
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 per second).
Astronomy & Astrophysics 101: What Is a Light-Year?
Dec 15, 2024 · 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 trillion miles (9.46 trillion kilometers) …
Convert 1 Light Year to Miles - CalculateMe.com
How long is 1 light year in miles? 1 ly to mi conversion. 1 light year is equal to about 5.88 trillion miles. A light year is the distance that light travels in one year. The year used by the International …
Light-years to Miles calculator - calculatemate.com
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. As defined by the International Astronomical Union (IAU), a light-year …
Convert Miles to Light Years – Simple Formula & Cosmic Examples
Learn how to convert miles to light years with a simple formula. Includes real examples, cosmic scale comparisons, and FAQs for astronomy fans.
Understanding Light Years: How Far Is Far in Space?
May 3, 2025 · Multiply that speed by the number of seconds in a year—roughly 31.5 million—and you get the grand total: one light year equals about 9.46 trillion kilometers (or about 5.88 trillion miles).