What is a baseline in astronomy?
Great question! but cannot be answered in one line... read on!!
The baseline in astronomy would probably be stars? planets? black holes? or what? It took me a while to answer this question and i had to go to numerous websites, use many books and what not, and i finally was able to scratch this answer out-
In extremely simple terms a baseline is a minimum point used for comparisons. In our universe to assess the distance between 2 bodies or to assess the size of a body, the earth can be considered a starting point with relation to the sun or the moon and to the body. In this process however, satellites and telescopes are used by astronomers.
Hope this was helpful!