Learn the basics of how stars work, the different kinds of stars, and why some stars are hotter and brighter than others. For more information, I recommend the following books: Stellar Evolution and Nucleosynthesis by Ryan and Norton Stellar Interiors by Hansen, Kawaler, and Trimble Stars and Stellar Evolution by De Boer and Seggewiss Stellar Structure and Evolution by Kippenhahn, Weigert, and Weiss Images from ESA/Herschel/NASA/JPL-Caltech NSO, NSF, AURA, Inouye Solar Telescope Andrea Piacquadio