* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Lesson #4: The Moon and its Phases
Antikythera mechanism wikipedia , lookup
Chinese astronomy wikipedia , lookup
Astronomical clock wikipedia , lookup
Lost Cosmonauts wikipedia , lookup
Rare Earth hypothesis wikipedia , lookup
History of Solar System formation and evolution hypotheses wikipedia , lookup
Geocentric model wikipedia , lookup
Formation and evolution of the Solar System wikipedia , lookup
Extraterrestrial life wikipedia , lookup
Astronomical unit wikipedia , lookup
Late Heavy Bombardment wikipedia , lookup
Comparative planetary science wikipedia , lookup
Dialogue Concerning the Two Chief World Systems wikipedia , lookup
Satellite system (astronomy) wikipedia , lookup
Extraterrestrial skies wikipedia , lookup
Earth and Space Science Lesson #4: The Moon and its Phases Time Frame: 1 session of 30 minutes Learning Standards: The Earth in the Solar System 13) Recognize that the earth is part of a system called the “solar system” that includes the sun (a star), planets, and many moons. The earth is the third planet from the sun in our solar system. 15) Describe the changes that occur in the observable shape of the moon over the course of a month. Skills of Inquiry: - Participation as a class in the demonstration Student will be able to: Describe, compare, and explain the motions of planets, moons, and comets in the solar system. Describe and explain common observations of the day and night skies. Explain common observations of the day and night sky. Background Information for Teacher: Moon Phases Simplified: It's probably easiest to understand the moon cycle in this order: new moon and full moon, first quarter and third quarter, and the phases in between. As shown in the above diagram, the new moon occurs when the moon is positioned between the earth and sun. The three objects are in approximate alignment (why "approximate" is explained below). The entire illuminated portion of the moon is on the backside of the moon, the half that we cannot see. At a full moon, the earth, moon, and sun are in approximate alignment, just as the new moon, but the moon is on the opposite side of the earth, so the entire sunlit part of the moon is facing us. The shadowed portion is entirely hidden from view. The first quarter and third quarter moons (both often called a "half moon"), happen when the moon is at a 90 degree angle with respect to the earth and sun. So we are seeing exactly half of the moon illuminated and half in shadow. Once you understand those four key moon phases, the phases between should be fairly easy to visualize, as the illuminated portion gradually transitions between them. An easy way to remember and understand those "between" lunar phase names is by breaking out and defining 4 words: crescent, gibbous, waxing, and waning. The word crescent refers to the phases where the moon is less that half illuminated. The word gibbous refers to phases where the moon is more than half illuminated. Waxing essentially means "growing" or expanding in illumination, and waning means "shrinking" or decreasing in illumination. Thus you can simply combine the two words to create the phase name, as follows: After the new moon, the sunlit portion is increasing, but less than half, so it is waxing crescent. After the first quarter, the sunlit portion is still increasing, but now it is more than half, so it is waxing gibbous. After the full moon (maximum illumination), the light continually decreases. So the waning gibbous phase occurs next. Following the third quarter is the waning crescent, which wanes until the light is completely gone -- a new moon. Anticipatory Set: Explain to the students that they will be required to work together as a class to understand the demonstration of moon phases. Activity: 1. Turn on the model sun and turn off the other lights in the room. Have your students stand. Tell them in this system the lamp is the sun and their head is the earth. Their nose is their hometown on the surface of the earth. 2. Ask your students to stand so that it is noon in their hometown. (Their nose should point toward the sun.) Have them turn (rotate) until it is midnight in their hometown. I have my students rotate in a counterclockwise direction to simulate the direction as seen from the North Pole. (Midnight is when they have their backs to the sun.) Students can also rotate to show dawn and dusk in their hometowns and get an idea why the sun appears to rise in the east and set in the west. 3. Hand out the lunar lollipops (moons) and tell your students that it should be held at arm's length away from their head. Demonstrate how the moon orbits the earth in a counterclockwise fashion (from right to left). As students watch their moon they will see that it will go through phases similar to those of the real moon. 4. Go through the 8 major phases of the moon with your students. a. New moon - moon is between the sun and the earth and they see the shadowed side of the moon. A solar eclipse occurs in this phase when the moon blocks light from the sun from reaching a portion of the earth. Students can close one eye and simulate this event. b. Waxing crescent - rotating from a new moon toward a first quarter, backwards "c" shape will appear on the moon. c. First quarter - right half of the side of the moon facing earth is lit. The right shoulder is point towards the sun. d. Waxing gibbous - rotating from a first quarter to a full moon. e. Full moon - earth is between the moon and the sun, the entire lit side of the moon is visible on earth, (students' backs are to the sun and moons are lifted up to be lit). A lunar eclipse occurs when the moon passes through the earth's shadow. Have your students simulate this event. f. Waning gibbous - rotating from a full moon to a last quarter, less and less of the moon is lit each night g. last quarter - left half of the side of the moon facing the earth is lit, left shoulder is pointing to the sun. h. Waning crescent - rotating from a last quarter to a new moon, a "c" shape of light is seen on the left side of the moon. 5. Have your students repeat the phases on their own as you circulate through the room to correct any problems. Closure: Ask students which moon phases they remember and how often they have seen these moons. How often is the moon full? Is the moon a star like the sun? Where is it found in relation to the other parts of the solar system they have learned about? Have students locate the moon on the classroom solar system map and remind them to make a sketch of where it is so that they will be prepared for the next week’s lesson where they will be building their own models of the solar system. Assessment: Group participation in moon phase demonstration and class discussion. Resources and Materials: Light bulb (suspended from ceiling or on a stand), Styrofoam balls 2-3 inches in diameter (1 per student), and plenty of room for your students to rotate in! Note: Before this lesson you will need to do a little preparation. It is important to make sure the lights for the "suns" work. Also, either prepare the lunar lollipops by impaling the balls on a pencil, bamboo skewer or wood splint for a handle (or have students do this during lesson).