What Is A Light Year In Astronomy

Looking back in time.

What is a light year in astronomy. It is well over 9 trillion kilometres or about 6 trillion miles. The julian year is the basis of the definition of the light year as a unit of measurement of distance. How can this be. One light year is about 6 trillion miles 9 trillion km.

A light year is the distance traveled by light moving in a vacuum in the course of one year at its accepted velocity of 299 792 458 meters per second 186 282 miles per second. As defined by the international astronomical union iau a light year is the distance that light travels in vacuum in one julian year 365 25 days. A light year is an astronomical unit of distance equal to 9 5 trillion kilometers 5 9 trillion miles defined as the distance light travels in an earth year. A light year is the distance a beam of light travels in a single earth year or 6 trillion miles 9 7 trillion.

A light year equals about 9 46073 1012 km 5 87863 1012 miles or 63 241 astronomical units. Light travels at a speed of 186 000 miles or 300 000 km per second. A light year equals about 9 46053x1012 km 5 878x1012 miles or 63 240 astronomical unit s. A light year is how astronomers measure distance in space.

Think of it as the bigger badder cousin. A light year is the distance light travels in one earth year. It s defined by how far a beam of light travels in one year a distance of six trillion miles. A light year or light year abbreviation.

A light year is a measurement of distance and not time as the name might suggest. 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. Ly 3 is a unit of length used informally to express astronomical distances. Because it includes the word year the term light year may be misinterpreted as a unit of time.