Glossary

(Note: This activity is an extension of Activity 2; so the setup remains the same. For this role play, merge three pairs and make groups of 6. In each group, one student acts as the Earth, one acts as the Sun, and the remaining students are the stars. Ask students to choose a different role than the one they performed in Activity 2.)

Role Play : Apparent Motion of the Stars

Procedure:

1. The Sun and the Earth should stand facing each other. Ask the stars to stand a few paces around the Earth and the Sun, as shown in Figure 2.
2. At this point, it is noon for Nitu (the person on the nose). She will not see any stars either because of the sunlight or because they are out of her sight.
3. Ask the Earth to rotate anticlockwise slowly and to observe the positions of the Sun, the stars and the surroundings. As the Sun sets for Nitu, she will be able to see stars on the eastern horizon. As it gets darker, she will be able to see stars all over.
4. At midnight, the stars which were on the eastern horizon in the evening ,will be overhead for Nitu. The stars which were overhead in the evening will appear to be setting, and yet other stars will be rising on eastern horizon.
5. When it is dawn for Nitu, the stars which were at the zenith at midnight will appear to be setting. The sunlight will start dominating the eastern horizon, and slowly, all the stars will become invisible.
6. Because of the Earth’s rotation, the stars also appear to move from east to west just like the Sun. All celestial bodies follow this pattern.

Figure 2: Apparent motion of the stars