Solar system - Formation, Outer Planets, Moons

solar system

Table of Contents

Introduction & Top Questions
Composition of the solar system
- Orbits
- Planets and their moons
- Asteroids and comets
- The interplanetary medium
Origin of the solar system
- Early scientific theories
  - The Kant-Laplace nebular hypothesis
  - Twentieth-century developments
- Modern ideas
  - Formation of the solar nebula
  - Differentiation into inner and outer planets
  - Later stages of planetary accretion
  - Formation of the outer planets and their moons
  - The small bodies
  - Formation of ring systems
  - Solution to the angular momentum puzzle
- Studies of other solar systems

References & Edit History Related Topics

Images, Videos & Interactives

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Discover how the solar system, which started as a shapeless spherical blob ended up being flat

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This general scheme of planet formation—the building up of larger masses by the accretion of smaller ones—occurred in the outer solar system as well. Here, however, the accretion of icy planetesimals produced objects with masses 10 times that of Earth, sufficient to cause the gravitational collapse of the surrounding gas and dust in the solar nebula. This accretion plus collapse allowed these planets to grow so large that their composition approached that of the Sun itself, with hydrogen and helium the dominant elements. Each planet started with its own “subnebula,” forming a disk around a central condensation. The so-called regular ...(100 of 6329 words)

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