Download Intro to the Solar System Note 15 Solar System Components: * Sun

Intro to the Solar System
Note 15
Solar System Components:
* Sun
* 9 planets and their satellites (moons)
* Asteroids (various size rocks mainly
orbiting between Mars & Jupiter)
* Comets (large dirty snowballs!)
* Meteoroids
Planet Positions
* a planet’s orbit lies in a flat plane (like a
sheet of paper)
* orbital planes of planets are tilted slightly
(most are within 3° of Sun’s equator)
°
* Mercury is 5 off, Pluto is 17° off
Planet Types
A. Terrestrial (Earthlike) Planets
(AKA inner planets)
* includes Mercury, Venus, Earth & Mars
* small, dense & rocky
- Mercury and Mars have a lot of craters
- Earth & Venus don't (Why?)
* low escape velocities (easier to leave planet
because gravity tends to be less powerful due
to their smaller sizes)
B. Jovian (Jupiterlike) Planets
(AKA outer planets)
* includes Jupiter, Saturn, Uranus & Neptune
* very large, low density, gaseous
* thick atmospheres composed of hydrogen
(H), Helium (He), Methane (CH4), Ammonia
(NH3)
* high escape velocities (hard to leave planet
because of strong gravitational pull)
C. Pluto –
- not included in either group
- at times considered to be a satellite of
Neptune