What is the key observational contradiction between inferred gravitational mass and observed visible mass in spiral galaxies?
Answer
The calculated gravitational mass continues to increase or remains flat where visible light drops off
The rotation curve remaining flat or increasing far out, contrary to the expected Keplerian decline based only on visible matter, demonstrates that unseen mass provides the necessary gravitational pull.
#Videos
Astrophysics: Galaxy Rotation Curves and Dark Matter - YouTube
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