Solar_system_formation

Module Three: Formation of the Solar System

Overview of the Solar System

• Commonly recognized planets: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune (and sometimes Pluto).

• Terrestrial Planets: Mercury, Venus, Earth, Mars (smaller, rocky).

• Jovian Planets: Jupiter, Saturn, Uranus, Neptune (larger, gas giants).

• Mention of various celestial bodies: asteroids, comets, and dwarf planets.

Nebula Contraction Theory

• Defined: A nebula is a cloud of gas and dust in space, about a light year wide.

• Components of a nebula:

  • Gas: Mainly hydrogen and helium.

  • Dust: Small particles including ice chips and molecules.

Understanding Light Year

• Definition: The distance light travels in one year.

• Calculation:

  • Light travels 299,792 kilometers per second.

  • This vast distance constitutes the size of a nebula (approximately one light year).

What Triggers Nebula Contraction?

• Hypotheses include:

  • An exploding star (supernova) disrupting equilibrium.

  • Collision with another nebula causing gravitational disturbance.

  • Speculative idea of external space interactions, like fictional scenarios.

Dynamics of Nebula Contraction

• The contraction leads to increased spinning:

  • As the nebula contracts, conservation of angular momentum causes it to spin faster.

  • Analogy: Ice skater pulling in arms to spin faster.

• Result: The nebula flattens into a disk.

  • The plane aligns with the rotating disks of stars, including the sun’s equator.

Contraction to the Disk Stage

• Nebula shrinks to about 100 Astronomical Units (AU) from the sun.

• Definition of AU: The average distance from Earth to the Sun (approximately 93 million miles).

Evidence of Nebula Contraction Theory

• Observation of Beta Pictoris, a star currently evolving from a nebula-like structure, about 100 million years into its lifecycle.

• Visual representation: Not yet flat in terms of solar system formation.

Nebula Condensation Theory

• The condensation of molecules in the nebula leads to two significant outcomes:

  • Formation of larger masses from molecule collisions.

  • The cooling of the nebula, allowing for more particle aggregation.

Analogy of Raindrop Formation

• Raindrop development compared to nebular dust particle interactions:

  • Dust serves as condensation nuclei, encouraging gas to gather and link.

  • Result: Formation of small clumps that can grow larger and eventually become planetesimals (baby planets).

The Nice Model

• Updated computer model for understanding the solar system’s formation using better gravitational calculations.

• Description of the model: The new data provides a refined perspective on planetary development in the solar system.