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Jens
2009-May-14, 02:47 AM
I have a question about galaxy rotation curves. I know the processes are quite different, but is there any resemblance to the rotation curve of a tropical storm? They look quite similar, with arms and stuff. I can think of a major difference, in that there is no "eye" of a galaxy, but what about the rotation curves of the arms?

WayneFrancis
2009-May-14, 04:39 AM
someone can correct me if I'm wrong but the rotation curve of a spiral galaxy is much different then the rotation curve of the visible arms.

My understanding is that the matter within the disk isn't moving as fast as a compression wave that causes new star forming regions thus the visual appearance of the arms.

The cause of the rotation is very different too. One is a high/low pressure system the other is gravity.

Jens
2009-May-14, 04:46 AM
I think maybe I could have made the question simpler, by asking, do tropical storms have a flat rotation curve, or does the wind get weaker little by little as you move out from the center?

PraedSt
2009-May-14, 07:38 AM
I think maybe I could have made the question simpler, by asking, do tropical storms have a flat rotation curve, or does the wind get weaker little by little as you move out from the center?
Yep, in a tropical storm, the wind speed gets lower as you move out from the centre. Ignoring the eyewall discontinuity.