Astronomy & Space Science · AST-156
Accretion & Planetary Differentiation: Foundations
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Overview
What Accretion & Planetary Differentiation means
Accretion is the growth of planetary bodies through collisions and gravitational capture of smaller material, while differentiation is the internal separation of materials by density after a body becomes hot enough for substantial melting or flow. Together these processes transform primitive disk material into layered planets.
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References & evidence
Source library for this chapter
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- 01Formation of the Solar SystemOpen source ↗
OpenStax Astronomy 2e
- 02Composition and Structure of PlanetsOpen source ↗
OpenStax Astronomy 2e
View claim-by-claim traceability3 verified claims
As a growing body becomes more massive, gravitational focusing increases the effective collision cross-section and accelerates accretion.
supported · checked Sep 22, 2026Planet densities, seismic measurements, gravity fields, magnetic fields, meteorites, and returned samples reveal differentiated interiors.
supported · checked Sep 22, 2026Accretion is the growth of planetary bodies through collisions and gravitational capture of smaller material, while differentiation is the internal separation of materials by density after a body becomes hot enough for substantial melting or flow.
supported · checked Sep 22, 2026