So I was interested in how astronomers measure the distances to other stars, galaxies, etc and I found this pdf about the subject http://articles.adsabs.harvard.edu/cgi-bin/nph-iarticle_query?1992PASP..104..599J&data_type=PDF_HIGH&whole_paper=YES&type=PRINTER&filetype=.pdf [Broken] It seems to be a good source but I still don't understand exactly how it is done, and don't have a high level of math understanding yet. I'm mostly interested in the globular cluster luminosity function, and the steps taken to actually get a distance to another galaxy etc. I understand a little bit about it but there is quite a bit such as the math that I don't understand. Can anyone help and explain this to someone who doesn't know much about the subject? Thank you.