We cannot limit ourselves to H II regions within our own Galaxy. Because of their low surface brightness, there are few observable old H II regions in the northern Milky Way. To increase the number of objects and also build an extragalactic database for comparison, we will use H Fabry-Perot data cubes of the southern and central parts of M33. That data has already been through the process of reduction and is now being analyzed. Velocity fields for the oldest H II regions will be extracted with precautions taken to avoid giant extragalactic H II regions.
North is up and east is to the left.
North is up and east is to the left.