The Formation of Globular Cluster Systems: how, when, and where?

Globular clusters, as fossil remnants of the protogalactic era, provide unique traces of the earliest events of galaxy formation. However, new observations – especially from HST – are showing that massive, globular-like star clusters belong not only to the pregalactic era but can form right up to the present day under the right circumstances. Appropriate interpretation may now let us learn simultaneously about the process of cluster formation as well as the nature of the gaseous fragments from which the galaxies were assembled.