AST-513intermediate

Milky Way Rotation & Dark Matter: Physical Mechanisms

The rotation of the Milky Way shows that visible stars and gas do not account for all of its gravitational mass. Milky Way dynamics constrain dark-matter halo shape and density, determine the Galaxy's total mass, and set the gravitational environment for stellar streams, satellites, and Solar-System motion through the Galaxy.

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Milky Way Rotation & Dark Matter: Physical Mechanisms

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AST-512Milky Way Rotation & Dark Matter: Structures & Vocabulary→

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AST-514Milky Way Rotation & Dark Matter: Observation, Measurement & Evidence→

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The rotation of the Milky Way shows that visible stars and gas do not account for all of its gravitational mass.

supported

For a nearly spherical mass distribution, orbital speed depends on the mass enclosed within the orbit.

supported

Measurements of neutral hydrogen, molecular masers, stellar velocities, satellite motions, and local stellar dynamics all require more gravitating mass than can be supplied by observed baryonic matter alone.