1. 23.3 The Outer Planets

2. Jupiter: Giant Among Planets
Mass that is 2.5 times greater than the mass of all the other planets & moons combined
Rotates quickest (1 rotation = 10 Earth yrs.)
Alternating bands of multicolored clouds (caused by wind systems)
Great Red Spot in SH

3. Continued…
Hydrogen-Helium atmosphere (w/ small amts. of methane, ammonia, water, & sulfur)
Gives off 2x more heat than received
Atmospheric pressure at the top of clouds is = to sea level pressure on Earth
Pressure increases as you reach surface
28 moons discovered so far
Rings are composed of fine, dark particles

5. Saturn: The Elegant Planet
Most prominent feature is its system of rings
Atmosphere is very active
Large cyclonic “storms” occur in atmosphere
Each ring is composed of individual particles (“moonlets”) of ice & rock
Rings fall into 2 categories based on density
31 moons (Titan is the largest)

7. Uranus: The Sideway Planet
Rotates on its “side”
Instead of being generally perpendicular to the plane of its orbit like the other planets, Uranus’s axis of rotation lies nearly parallel with the plane of its orbit

9. Neptune: The Windy Planet
Atmosphere like Jupiter & Saturn
Winds exceed 1000 km per hr. (one of the windiest in the solar system)
Great Dark Spot
White, cirrus like clouds (likely frozen methane)
13 moons (Triton represents retrograde motion)
Shows that Triton formed independently of Neptune & was gravitationally captured

11. Pluto: Planet X
Since its discovery in 1930, it has completed about ¼ of a revolution
Orbit is highly eccentric, causing it to occasionally travel inside the orbit of Neptune, where it stayed from 1979 – Feb. 1999
Avg. temp. is -210 degrees Celsius

12. REVIEW What is the largest planet? What is the smallest planet?
Identify 1 distinguishing characteristic of each outer planet.
How are Titan & Triton similar?

13. 23.4 Minor Members of the Solar System

14. Asteroids: Microplanets
Small rocky bodies that have been likened to “flying mountains”
Lie btw the orbits of Mars & Jupiter
Orbital periods of 3-6 years
Irregular shapes

15. Comets
Pieces of rocky & metallic materials held together by frozen gases, such as water, ammonia, methane, CO2, and carbon monoxide
Elongated orbits
Coma – glowing head
A small glowing nucleus with a diameter of only a few km can sometimes be detected within a coma
As comets approach the sun, some, but not all, develop a tail that extends for millions of km

17. Continued…
Kuiper Belt – comets with short orbital periods that orbit beyond Neptune
Circular orbits
Oort Cloud - comets with long orbital periods aren’t confined to the plane of the solar system
Halley’s comet is the most famous short – period comet

18. Meteoroids Small solid particle that travels through space
Originate from any one of the following 3 sources:
Interplanetary debris that was not gravitationally swept up by the planets during the formation of the solar system
Material from the asteroid belt
The solid remains of comets that once traveled near Earth’s orbit
A meteoroid that reaches Earth is called a meteorite