Ch. 3 The Solar System Outline (Book Objectives and Figures)
Section 1: The Solar System (p. 70-74)
1) Obj: Compare models of the solar system Earth centered model-Earth at the center of the solar system all the planets and sun revolve around the earth. WRONG!!
 Sun centered model- Sun at the center of the solar system all planets revolve around the sun. CORRECT!!
2) Obj: Explain that gravity holds planets in orbit around the sun The sun contains 99.86% of the mass of the entire solar system therefore the sun’s gravity is immense.
 The more mass = stronger the gravitational force.
3) Obj: Summarize how the solar system was created 4.6 billion years ago a cloud of gas and dust started to contract and condense. The cloud continued to contract into a
tightly packed spinning disk. At the center of the disk was a not very dense mass that became a star once fusion began in
the core of the star. Eventually, the remaining gas, dust and debris cooled and clumped together into protoplanets.
Finally, the clumps collided and combined to form the 8 planets of our solar system.
 See page 73 Figure 3 Know this diagram!
Section 2: The Inner Planets (p. 76-81)
1) Obj: List the inner planets in order from the sun:
 Mercury, Venus, Earth, Mars
2) Obj: Describe each of the inner planets Mercury- closet to the sun, smallest planet, no atmosphere, very hot during the day and very cold at night.
 Venus- similar to earth in size and mass, thick sulfuric acid atmosphere, yellow in color, greenhouse effect heats up
planet to very high temperature, no moons, similar surface features to earth.
 Earth- atmosphere protects life, temperature are conducive to allow water to exist in all three phases, one large moon.
 Mars- red in color, very thin atmosphere, ice caps and signs of water, similar surface features to earth, two small moons.
3) Obj: Compare and contrast Venus to Earth Similar size, mass and surface features
 Different atmosphere (Venus is toxic and very thick), Venus is much hotter and cannot support life as we know it.
Section 3: The Outer Planets (p. 70-74)
1) Obj: Describe the characteristics of the outer planets
 Jupiter- Largest planet, mostly hydrogen and helium, four large moons, large red storm (Great Red Spot).
 Saturn- Second largest, complex system of rings, has at least 47 moons, mostly hydrogen and helium.
 Uranus- hydrogen, helium and methane atmosphere, axis is nearly parallel to plane of orbit.
 Neptune- similar to Uranus
2) Obj: Describe Io and Europa (moons of Jupiter)
 See page 83
 Io- lots of volcanoes, thin atmosphere
 Europa- very cold and covered with a thick layer of ice (possibly liquid water beneath).
Section 4: Other Objects in the Solar System (p. 90-93)
1) Obj: Distinguish between comets, asteroids, and meteoroids Comets- are like dirty snowballs, made of water and methane ice.
 Asteroids- large pieces of rock similar to what made the planets
 Meteoroids- pieces of rock and dust that come in contact with earth.