RSAA Colloquia / Seminars / Feast-of-Facts: Friday, 20 February 2015, 14:00-14:20; Duffield Lecture Theatre

Dougal Mackey

"Slowly-forming star clusters - fact or fiction?"

Many intermediate-age star clusters in the Magellanic Clouds exhibit very unusual features in their colour-magnitude diagrams that suggest they may have formed their stars over periods spanning hundreds of millions of years per cluster. This poses a major challenge for theoretical models and is at odds with what we think we observe for very young systems that are forming right now. Nonetheless, this interpretation is enticing in the context of the formation of ancient globular clusters, which almost always exhibit puzzling abundance patterns that apparently require multiple episodes of star formation to explain. I will review some recent developments in this field - can individual star clusters really form over such extended intervals, and are the Magellanic Cloud objects good stepping stones for understanding the formation of globular clusters?