What's on tonight at the AAT

Kinematics of stellar sub-structures in the Magellanic periphery

Dougal Mackey (Australian National University)

Tonight's observers are exploring the ghostly outskirts of one of our nearest neighbours -- the Large Magellanic Cloud (LMC). Our recent mapping of the extremely faint periphery of this galaxy has revealed the presence of several huge stellar sub-structures, but we do not yet understand the origin of these features. It could be that the tidal force of the Milky Way is stripping stars from the edges of the LMC, or perhaps a close encounter between the LMC and its companion the SMC is responsible. By measuring the velocities of stars in each different sub-structure we aim to explore these possibilities by comparing the results with detailed numerical models, and in doing so learn more about the past history of the Magellanic system.