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 …

Jan 1, 2026 · So, a light-year is 5.88 trillion miles (9.46 trillion km). However, stars and nebulae – not to mention distant galaxies – are vastly farther than one light-year away.

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).

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 …

Jan 20, 2026 · 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.

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.

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 …

Jan 29, 2026 · A lightsecond equals 300,000 km (186,000 miles). A lightminute is about 18 million km ( 11 million miles) and a lighthour is 1.1 billion km. One AU equals 8.3 light minutes and a …

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 …

May 28, 2020 · The light year or light-year (ly) is a unit of length that is the distance light travels in a vacuum in one Earth year. One light year is exactly 9460730472580.8 km (approximately …