The 'high velocity cloud' origin of the Magellanic system.

It is believed that the splitting of the SMC into two fragments and the production of the inter-Cloud gas (ICG) and the Magellanic Stream occurred in the one event 400 Myr ago. This event was a collision between the LMC and SMC. This time is too short for the Stream to be tidal, or be the result of stripping of the ICG by a diffuse gaseous halo. It is proposed that the clouds in the Stream are the results of collisions between the ICG and HVCs in the Galactic halo. A model of this process accounts for all of the observational features of the Stream. Observations of HVCs in the path of the Magellanic Clouds are used to predict the development of the Stream. The HVCs in the halo are thought to be a result of a collision of a galaxy with the Galaxy 6 Gyr ago.