Star Clusters

Star clusters are natural laboratories for stellar evolution because their stars formed from related material and are often at similar distances. Hubble resolves crowded cluster cores, allowing precise color-magnitude measurements and age estimates that are central to astrophysics. These datasets help scientists test stellar evolution tracks, trace metallicity history, and understand how clusters dynamically evolve under gravity and feedback. Some clusters in this category are young and actively forming massive stars, while others are ancient systems that preserve information from the early Milky Way. By comparing young and old clusters in one place, this section gives a clear, data-driven view of how stars and stellar systems change over cosmic time.