Name: Density Waves and the Stability of Galactic Spiral Arms @mrg3
Uploaded: 2008-02-29T01:29:31-0400
Duration: 8 min 17 s
Description: This animation shows how speeding up and slowing down of the orbital motions of stars in galaxies can lead to stable spiral arms. This animation is not based on a particular physical model of those density waves, but is my artist conception, to try to illustrate the concept.

Uploaded January 2011 | Updated September 2026, 3 weeks ago

The flow velocity of an uncompressible fluid is determined by the area of the pipe it is flowing through. The more constricted the pipe, the faster the fluid flows.

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Density Waves and the Stability of Galactic Spiral Arms