Astronomy & Space Science · AST-533
Galaxy Formation & Evolution: Physical Mechanisms
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Mechanism
Mechanism of Galaxy Formation & Evolution
Dark-matter overdensities collapse first and provide gravitational wells. Gas falls in, cools, forms stars, and can be expelled or heated by supernovae and active galactic nuclei. Mergers rearrange stellar orbits and gas, while fresh cosmic inflow can sustain later star formation.
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- 01The Evolution and Distribution of Galaxies — SummaryOpen source ↗
OpenStax Astronomy 2e
View claim-by-claim traceability3 verified claims
Dark-matter overdensities collapse first and provide gravitational wells.
supported · checked Sep 22, 2026Deep observations show that distant young galaxies are generally smaller, more irregular, and more actively star-forming than present-day massive systems.
supported · checked Sep 22, 2026Galaxies formed as small density fluctuations in the early universe grew through gravity, collected gas inside dark-matter halos, formed stars, and merged into larger structures.
supported · checked Sep 22, 2026