The discovery of multiple stellar populations in young and intermediate-age clusters has been one of the major findings in the field of stellar populations of the last decade. Their origin is one of the most-intriguing open issues of stellar astrophysics and provides new constraints on the assembly of galaxies and on star formation and evolution.
I will present new results for a large dataset of young clusters (GO-14710, PI. Milone) observed with the Hubble Space Telescope.
Our results allow us to understand the physical mechanism that is responsible for the multiple populations in young clusters and disentangle the effects of age variation and rotation.
The study of this young objects open new perspective in the understanding of multiple stellar populations that formed at high redshift a few hundreds million years after the Big Bang.