Because they are so far away
lightyear
It's calculated, not measured. It's the speed of light ... 299,792,458 meters per second ... multiplied by the number of seconds in a standard year.
Stars are not measured in light years. The distance between them is.
'Buzz Lightyear of Star Command' who is voiced by Tim Allen .
Buzz Lightyear
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.
Perhaps you mean the satellite Hipparcos. It measured the position of over 100,000 stars with high precision. It also measured the position of 2.5 million stars, with lower precision.
a mega lightyear
"Lightyear" is a noun. It is a unit of distance used to measure interstellar space.
A lightyear is a much larger distance.
Lightyear Capital was created in 2002.
Lightyear Capital's population is 20.