STAR FORMATION IN THE LEADING ARM OF THE MAGELLANIC STREAM

The Magellanic Clouds are the nearest example of a pair of interacting galaxies. The dynamics of their interaction has created the gaseous structures known as the Magellanic Stream trailing the pair's orbit about the Galaxy, the bridge between the Clouds, and the leading arm (LA), a wide and irregular feature leading the orbit. The LA must have a tidal origin, but a hydrodynamical interaction with the gaseous hot halo and disk of the Galaxy is required to reproduce its morphology and kinematics, as seen in neutral hydrogen (HI) observations. Here we show for the first time that young, recently formed stars exist in the LA, indicating that the interaction between the Clouds and our Galaxy is strong enough to trigger star formation in certain regions of the LA, in the outskirts of the MW disk, far away from the Clouds and the bridge.