The M81 group of galaxies provides an excellent laboratory for studying galaxy-galaxy interactions and the ensuing violent episodes of star formation. The starburst galaxy M82 is believed to have suffered a close encounter with M81 some 250 Myr ago which triggered the current nuclear starburst. We present Gemini-North optical spectroscopy of 50 massive star clusters distributed across the disk and central regions of M82. These data represent the largest spectroscopic dataset to date for extragalactic young clusters. We derive ages and radial velocities for these clusters, and find that M82 has been actively forming massive clusters for the last 50-270 Myr, with a peak close to 140 Myr. We discuss these results in the context of the last interaction with M81 and the propagation of cluster formation from the disk to the nucleus.
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