...what about the Alexander Brest Planetarium? I think it's pretty nice and we're lucky to have it. According to the lists from wikipedia and mapmuse, there are a few large cities without one atm.
http://en.wikipedia.org/wiki/List_of_planetariums
http://find.mapmuse.com/re1/map_brand_mm2.php?brandID=PLANETARIUM&init=27.9167,-83.6075,6&tlist=PLANETARIUM,