Why is it important for astronomers to understand the distance to other stars?
As it helps us to get more information about the universe we are living in.
It always had a significant in our world view. Astrology is a study of and about the stars. Because of astronomy only we have found that like the stars we are also made up of gas and dust.
Knowing the distance between the Venus and Sun and distance between Venus and Earth helps us to about the distance between Sun and Earth.
It also helps us to know about where are we now in the whole universe.
It is also used to measure the time, Navigate the vast oceans and mark(know about) the seasons.