What is a light year?

Definition
ly

A light year (ly) is the distance light travels in one year — approximately 9.461 trillion kilometers, used in astronomy.

Unit system
Scientific & Astronomical
All length units
UnitSymbolSystem
nanometers nm Metric
micrometers μm Metric
millimeters mm Metric
centimeters cm Metric
meters m Metric
kilometers km Metric
inches in Imperial / US
feet ft Imperial / US
yards yd Imperial / US
miles mi Imperial / US
nautical miles nmi Nautical & Aviation
light years ly Scientific & Astronomical