Plot of a rotation curve for a disk-shaped galaxy. This is a smooth curve that increases from r=0 to a peak somewhere around r = 0.5 R, and then drops off a bit more gradually than the previous plot.

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1. Robert McNees (mcnees@mastodon.social)'s status on Sunday, 23-Jul-2023 20:00:31 UTC Robert McNees

   in reply to

   Most of the galaxies we observe are not spherical. But a spiral galaxy (like our Milky Way) should have a qualitatively similar behavior.

   Roughly speaking, v increases with distance from the center, then at some point it begins to drop off.

   Here's the Newtonian gravity rotation curve for a disk-shaped galaxy.