Convert kilometers to light year

One light year is equal to 9.460E+12 km, or 9 460 000 000 000 km.

 

A light year is the distance light travels in a year, equal to 9,460,730,472,580.8 kilometers.

 

According to the International Astronomical Union (IAU) definition, a light year is equal to the distance that light travels in a vacuum, without the influence of gravitational fields, in one Julian year. This is the definition recommended for use in popular science literature.

 

Historically, a light year was defined as the distance that light travels in one tropical year, which refers to the time it takes for Earth to complete one full orbit around the Sun, based on the standards established in 1900. This measurement was primarily used in astronomy to express vast distances between celestial bodies.

 

A new definition for the light year has been introduced, which differs from the original one of the light year by approximately 0.002%. This small variation considers more precise measurements, but it does not matter. It represents our understanding of light and astronomical distances. It is important to note that the light year is generally not utilized in contexts requiring high levels of precision. As a result, for practical purposes, there is no significant difference between the old and new definitions of a light year, and both are commonly understood similarly within the scientific community.