H-R Diagram

The Hertzsprung-Russell (H-R) diagram is a vital tool in astronomy that categorizes stars based on their brightness (luminosity) and temperature. It typically displays temperature on the horizontal axis and brightness on the vertical axis. Most stars, including our Sun, fall along a diagonal band known as the "main sequence," where they spend most of their lifetime. Stars evolve over time, moving off this main sequence into different regions, such as giants or white dwarfs. By analyzing their positions on the H-R diagram, astronomers gain insights into a star's age, composition, and life cycle.