This guide describes the life cycle of stars and the H-R diagram. It also explains how distances to stars and other objects in the universe are measured.
You will find that the text contains many links. Some will take you to a glossary definition, while others are links to more information about a topic you may want to explore further. Please use this guide in the way that makes most sense to you. You may want to read the entire guide first, then go back and follow links that interest you, or you may want to follow links as you go along. You can also click on the diagrams to see them a larger size.