Variable Stars

Variable stars are stars whose brightness changes over time. These fluctuations can occur due to intrinsic factors, such as the star expanding and contracting or cyclic processes within it, or extrinsic factors like eclipses caused by a companion star passing in front. The variations can be regular, like a clockwork pattern, or irregular. Studying variable stars helps astronomers understand stellar processes, measure cosmic distances, and learn more about the life cycles of stars. They are important celestial tools because their brightness changes reveal underlying physical properties and behaviors of stars across the universe.