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David Lee Nidever
University of Virginia
 

"New Discoveries in The Clouds"
 

Using the Leiden-Argentine-Bonn all-sky HI survey we have discovered that one of the Magellanic Stream filaments and the Leading Arm can be traced back to the Southeast HI Overdensity (SEHO) of the Large Magellanic Cloud.  This is contrary to previous suggestions that these features originate in the Small Magellanic Cloud and the Magellanic Bridge.  Furthermore, there is evidence that gas outflow from supergiant shells in the SEHO region are creating the Magellanic Stream and Leading Arm.  Gas blowout provides a new and previously unexplored potential mechanism for creating the Magellanic Stream.  Additionally, we have surveyed the periphery of the Large Magellanic Cloud with CTIO+MOSAIC and HYDRA and discovered an extended population of LMC stars that reaches to 23 degrees from the LMC center.  The metallicity distribution of the outermost stars is bimodal, with most stars relatively metal-rich ([Fe/H]= -0.4) while a handful are metal-poor ([Fe/H]= -1.5).  Whether this new extended population of the LMC is a bound halo or tidal debris is not yet clear.