Because the definition of a lightyear is: how long light can travel in a year. Hope this helped;)
a lightyear
100km is a distance, not a measurement of time. (kilometres)
Accurate measurements of time become possible after accurate measurement of length and mass because time taken by a heavy body to move a certain distance is more,and time taken by a light body to move a certain distance is less.
Measurement always deals with a distance of a line or a distance between to objects, distance between 2 points, and so on.
A minute is a measurement of time. A light minute is a measurement of distance. it's the distance light would travel in one minute. (That's about 10 million miles!)
Yes.
A lightyear is the distance that light can travel in one year.
a mega lightyear
Lightyear isn't about time, it's distance. One lightyear is ten trillion kilometers.
A lightyear is a much larger distance.
a lightyear
"Lightyear" is a noun. It is a unit of distance used to measure interstellar space.
None, a furlong is a measurement of distance, and a year is a measurement of time.
Hour = measurement of time. Miles = measurement of distance.
a Lightyear, around 1013 kilometres.
100km is a distance, not a measurement of time. (kilometres)
The distance between stars is typically measured in light years, which represents the distance that light can travel in one year. This unit is used because distances in space are vast and need a large unit of measurement.