Chapter: 15. The Solar System
A. Fill in the blanks.
The Sun and its family is called the $\qquad$ The Sun is a ball of hot burning $\qquad$ A group of thousands of stars forms a $\qquad$ Large pits found on the surface of the Moon are called $\qquad$ B. Who am I?
I am the planet closest to the Sun: C. Tick the correct answers.
The natural satellite of the Earth is A pattern of stars seen in the sky is called a The name of our galaxy is The heavenly bodies that move around the Sun are called D. Answer the following questions orally.
An orbit is the fixed path that a planet follows as it travels around the Sun. Name a planet that has no natural satellite. Why do the stars look small even though they may be bigger than the Sun? Stars look small because they are very far away from us. Satellites are objects that go around a planet. They can be natural (like moons) or artificial (man-made). E. Answer the following questions.
What are constellations? Name three constellations. Constellations are groups of stars that form a recognizable pattern in the sky. Three constellations are Orion, Great Bear (Ursa Major), and Scorpio. What does our solar system consist of? Our solar system consists of the Sun, the eight planets, their satellites, and also pieces of rocks, dust, and gases. The eight planets are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune. How does an artificial satellite help us? Artificial satellites help us by providing information about other planets and the weather, and by enabling communication through television, telephone, and radio signals. Think Box
A. What is the difference between stars and planets?
* Stars are heavenly bodies that produce their own heat and light and are made of hot gases, while planets are heavenly bodies that do not produce their own light (they reflect light from a star) and orbit a star in a fixed path.
B. What would happen to the Earth if the Sun did not exist?
* If the Sun did not exist, the Earth would become completely dark and extremely cold. Without the Sun’s heat and light, life as we know it would not be possible on Earth.
Picture Study
Identify the two planets. The two planets are Saturn (the large, ringed planet on the left) and Earth (the blue and green planet on the right). Name three differences between these two planets. Saturn has prominent rings, while Earth does not. Saturn is much larger than Earth. Saturn is primarily a gas giant, while Earth is a rocky planet. Saturn has many natural satellites (moons), while Earth has only one. Earth supports life, whereas Saturn does not. 
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