 Galaxy color–magnitude diagram

The color-magnitude diagram (CMD) is a key tool in astrophysics, particularly in the study of stars and galaxies. For galaxies, the CMD is often used to illustrate the relationship between the color and brightness (magnitude) of the stars within those galaxies. ### Key Components: 1. **Color:** The color of a star is typically measured using different filters (often in the ultraviolet, visible, and infrared wavelengths).