Tuesday 11am March 3rd 2009 THE CHEMISTRY OF NAKED GALAXIES Marshall L. McCall York University Today, dynamically hot systems (elliptical galaxies, spiral bulges, and dwarf spheroidal galaxies) are "naked" from the standpoint of being devoid of gas. Was all the gas used up in forming the stars? Or, did these bodies lose their gas by some other means? Studies of the chemical composition of planetary nebulae help to tell the tale, and even elucidate how much baryonic matter the systems started with. WARNING: An attempt will be made to create a galaxy in a container. It might get gruesome.