Objectives:
1. How did the solar system form?
The Nebular Theory the sun and planets formed from a rotating disk of dust and gases.
As the speed of the rotation increased, the center disk began to flatten concentrating matter in the center, where the sun eventually formed.
2. How do terrestrial planets form?
Solid bits of matter began to collide in a process known as accretion forming small irregularly shaped planetesimals.
Eventually, they became large enough to exert gravity and grew to become planets.
The four inner terrestrial planets closest to the sun are terrestrial as they are too warm for ices to form
The four outer Jovian planets frigid enough for ices of water and other substances to accumulate
Comparison of terrestrial and Jovian planets
Terrestrial | Jovian | |
Orbits | Close together |
Far apart
|
Diameter | Small | Large
|
Density | More dense | Less dense
|
Rotation | Slower | Faster
|
Atmosphere | Thin or absent | Thick
|
Composition | Rocky and metallic substances with few gases and ices | Mostly made of gases, liquids, and ices, but with rocky and metallic materials in their cores |