Grade 9 Earth & Space
CHAPTER 8.1 (only table)
Property Outer Planets - Gas Planets Inner Planets - Terrestrial
Size Larger Smaller
Made up of Gases Rock
Length of “Year” Longer Shorter
Proximity to the Sun Further Closer
Temperature Cooler Hotter
Review Definitions
Celestial Object: any object that exists in space.
Planet: a large, round celestial object that travels around a star.
Asteroid: small celestial objects in the Solar System composed of rock and metal.
Meteor: a bright streak of light across the sky as it is pulled down into the Earth’s
atmosphere—known as a shooting star.
Meteoroid: a piece of metal or rock in the Solar System that is smaller than an asteroid.
Meteorite: remains (“crumbs”) from the meteoroid that crashed to the ground.
Satellite: a celestial object that travels around a planet or dwarf planet.
Comet: a blanket of ice that travels in a very long orbit around the Sun.
,CHAPTER 8.3
Characteristics of the Planets (Probably 8.1)
Asteroid Belt
● The vast majority of asteroids lie in an area known as the asteroid belt, located between
the orbits of Mars and Jupiter.
, CHAPTER 8.5
Two Types of Motion:
1. Rotation
2. Revolution
Earth’s Rotation
● The motion of the Sun in the sky is caused by the rotation of
Earth on this axis.
● Earth makes one complete rotation, it a west-to-east
direction, once each day (24 hours)
● During its rotation, the portion of Earth that faces the Sun
experiences daylight.
○ The portion facing away from the Sun experiences
darkness.
Earth’s Revolution
The Earth also revolves/travels around the Sun.
● The distance of each planet from the Sun changes as it
completes its orbit around the Sun.
○ Because the Sun is located closer to one end of the
elliptical path.
● The shape and size of a planet’s orbit affects the time that it takes to complete a
revolution around the Sun, a value which we call an ORBITAL PERIOD.
CHAPTER 8.1 (only table)
Property Outer Planets - Gas Planets Inner Planets - Terrestrial
Size Larger Smaller
Made up of Gases Rock
Length of “Year” Longer Shorter
Proximity to the Sun Further Closer
Temperature Cooler Hotter
Review Definitions
Celestial Object: any object that exists in space.
Planet: a large, round celestial object that travels around a star.
Asteroid: small celestial objects in the Solar System composed of rock and metal.
Meteor: a bright streak of light across the sky as it is pulled down into the Earth’s
atmosphere—known as a shooting star.
Meteoroid: a piece of metal or rock in the Solar System that is smaller than an asteroid.
Meteorite: remains (“crumbs”) from the meteoroid that crashed to the ground.
Satellite: a celestial object that travels around a planet or dwarf planet.
Comet: a blanket of ice that travels in a very long orbit around the Sun.
,CHAPTER 8.3
Characteristics of the Planets (Probably 8.1)
Asteroid Belt
● The vast majority of asteroids lie in an area known as the asteroid belt, located between
the orbits of Mars and Jupiter.
, CHAPTER 8.5
Two Types of Motion:
1. Rotation
2. Revolution
Earth’s Rotation
● The motion of the Sun in the sky is caused by the rotation of
Earth on this axis.
● Earth makes one complete rotation, it a west-to-east
direction, once each day (24 hours)
● During its rotation, the portion of Earth that faces the Sun
experiences daylight.
○ The portion facing away from the Sun experiences
darkness.
Earth’s Revolution
The Earth also revolves/travels around the Sun.
● The distance of each planet from the Sun changes as it
completes its orbit around the Sun.
○ Because the Sun is located closer to one end of the
elliptical path.
● The shape and size of a planet’s orbit affects the time that it takes to complete a
revolution around the Sun, a value which we call an ORBITAL PERIOD.
