First 3D view of the formation and evolution of globular clusters

Nov. 5 () –

A detailed observation of movement of stars within globular clusters has provided the first 3D kinematic analysis of 16 such structures in our galaxy.

The investigation, published in Astronomy & Astrophysicsopens new perspectives on our understanding of the formation and dynamical evolution of multiple stellar populations in globular clusters, spherical and very compact agglomerations of stars, usually made up of between 1 and 2 million stars.

“The results of our study provide the first concrete evidence that globular clusters were generated through multiple star formation events and impose fundamental constraints on the dynamical path followed by clusters during their evolution,” explains in a statement Emanuele Dalessandro, researcher at INAF in Bologna, first author of the article and coordinator of the working group.

These results were possible thanks to a multiple diagnostic approach and the combination of observations and state-of-the-art dynamic simulations, he added. Study highlights that kinematic differences between multiple populations are extremely useful to understand the mechanisms of formation and evolution of these ancient structures.

With ages that can reach 12,000-13,000 million years (therefore, until the dawn of the cosmos), globular clusters are among the first systems that formed in the universe and represent a typical population of all galaxies. They are compact systems – with masses of a few hundred thousand solar masses and dimensions of a few parsecs – and observable even in distant galaxies.

“Their astrophysical relevance is enormous,” says Dalessandro, “because they not only help us verify the cosmological models of the formation of the Universe thanks to their age, but they also offer us natural laboratories to study the formation, evolution and chemical enrichment of galaxies”.