The oldest star clusters in the Magellanic Clouds: A common epoch of globular cluster formation

In the past three years, observations of old Large Magellanic Cloud globular clusters with WFPC2 have produced age determinations of unprecedented accuracy. The conclusion is that the LMC clusters are the same age as Milky Way clusters. The sample includes both clusters close to the LMC center (Olsen et al. 1998) and clusters on the outskirts (Johnson et al. 1999). The consequences for the formation of the Galactic Halo and the use of the second-parameter as an age discriminant will be presented. Assuming that globular clusters are created in secondary processes during the collapse of a galaxy, the globular cluster information will also be used to discuss the formation of the LMC and Galaxy in context of cold dark matter models of galaxy formation.