Light Year (ly)
Definition: A light-year (ly) is the distance light travels in one Julian year (365.25 days), approximately 9.461 trillion kilometers or 5.878 trillion miles. It is used for measuring astronomical distances.
History: The term 'light-year' was first introduced in the 19th century to help astronomers express cosmic distances. It replaced astronomical units that were cumbersome for measuring vast space distances.
Current Use: Light-years are used in astronomy to describe distances between stars, galaxies, and other celestial objects. It is crucial for understanding the scale of the universe and cosmic events.
Kilometer (km)
Definition: A kilometer (km) is equal to 1,000 meters. It is a common unit for measuring large distances, especially in geography and transportation, providing a practical scale for road signs and geographic mapping.
History: Introduced in the metric system during the late 18th century, the kilometer was established to replace inconsistent units of distance measurement across different regions, bringing standardization to the scientific community.
Current Use: Kilometers are widely used in most countries for measuring road distances, running races (e.g., 5K and 10K races), and geographical measurements. It remains the primary unit for long distances in metric countries.
Quick Conversion Table Light Year (ly) to Kilometer (km)
1 Light Year (ly) equal to 9.46053e+12 Kilometer (km)
5 Light Year (ly) equal to 4.73026e+13 Kilometer (km)
10 Light Year (ly) equal to 9.46053e+13 Kilometer (km)
20 Light Year (ly) equal to 1.89211e+14 Kilometer (km)
30 Light Year (ly) equal to 2.83816e+14 Kilometer (km)
50 Light Year (ly) equal to 4.73026e+14 Kilometer (km)
75 Light Year (ly) equal to 7.09540e+14 Kilometer (km)
100 Light Year (ly) equal to 9.46053e+14 Kilometer (km)