a. Ask students if they have ever experienced a similar phenomenon.
b. Ask students how this phenomenon might be used, especially in astronomy.
2. Have students predict what would happen as Frances moved closer to the bottle, then looked at the wine bottle with one eye open, then alternating eyes. Have them predict what would happen as Frances moves farther away from the bottle. Would the bottle move more or less?
3. Have students draw this situation on a piece of paper. Have them draw the bottle, Frances' eyes, and the position of the bottle in the background.