1. Formation of the Solar System
How did Earth form?

2. Collapsing Interstellar Clouds
Stars and planets form from clouds of gas and dust, called interstellar clouds
Consist of gas: Hydrogen and Helium
Usually low density, can condense due to gravity and form a star or a planet.

3. At first the collapse is slow, but it accelerates and the cloud soon becomes much denser at its center.
It will spin faster and faster as it contracts (ice skater pull arms to body to spin faster)
Eventually slows and cloud
becomes flattened, becoming
a rotating disk.

4. Sun and Planet Formation
The disk of dust and gas that formed the Sun and planets is known as the solar nebula.
Dense concentration at center became the Sun.

5. Temperature differed, Hotter at center and cooler at edges of disk
Due to temp differences different compounds were able to condense depending on distance from Sun

7. Overall result was the planets
Condensed material accumulated to from larger bodies.
Planetismals – Space object built of solid particles that can form planets through collisions and merges
Overall result was the planets

8. Early Planets
Jupiter formed first, using much of the material around it
This is why Jupiter is the largest Planet
The sun took most of the gas from the inner planets
This is why they are solid with few moons

9. Debris Most collided into planets or was sent out of the solar system.
The remnants remain in the asteroid belt between Jupiter and Mars.
Jupiter's gravitational force prevents them from forming into a planet.

10. Asteroids Rocky remnants of the early solar system
Most are less than 1 km in diameter, move slowly
C – Type (Carbon)
S – Type (Silica)
M - Type (Iron-Nickel)
Asteroid Belt
(Between Mars
and Jupiter)

11. Meteoroid – asteroid that begins to fall towards Earth
Meteor – Meteoroid that begins to burn up in Earth’s atmosphere
Meteorite – A meteor that does not complete burn up in atmosphere and strikes Earth’s surface
Less than 100 m in diameter
Move at fast speeds

12. Comets Small bodies of rock and ice that have highly eccentric orbits
Periodic Comets – repeatedly return to inner solar system
Halley’s Comet (76 Years, last seen 1985)
Kuiper Belt – Located Beyond Neptune
Come very close to Pluto in Aphelion, near sun at Perihelion

13. Parts of a Comet Coma Nucleus Tail Extended volume of glowing gas
Small solid core of the comet
Tail

14. Comet tails ALWAYS point away from sun
When come within 3 AU of the sun begin to evaporate
Gas and dust pushed away by radiation from sun
Meteor Shower – Earth intersects cometary orbit. Particles burn up in atmosphere