A day and night globe model is a simple classroom project that shows why different places on Earth have daylight or darkness. A globe represents Earth, and a flashlight represents the Sun. When the flashlight shines on one side of the globe, that side has day while the opposite side has night.
This model helps students see that day and night happen because Earth spins.
Key Facts
- Earth rotates once about every 24 hours.
- The Sun does not move around Earth to make day and night.
- The side of Earth facing the Sun has day.
- The side of Earth facing away from the Sun has night.
- Earth rotates from west to east, which makes the Sun appear to rise in the east.
- Time for one rotation = 24 hours, so 360 degrees ÷ 24 hours = 15 degrees per hour.
Vocabulary
- Rotation
- Rotation is the spinning motion of an object around its own axis.
- Axis
- An axis is an imaginary line through Earth from the North Pole to the South Pole that Earth spins around.
- Day
- Day is the time when a place on Earth is facing the Sun and receives sunlight.
- Night
- Night is the time when a place on Earth is turned away from the Sun and does not receive direct sunlight.
- Terminator
- The terminator is the boundary line between the lit daytime side and the dark nighttime side of Earth.
Common Mistakes to Avoid
- Moving the flashlight around the globe to make day and night is wrong because the model should show Earth rotating while the Sun stays in one place.
- Holding the flashlight too close is wrong because it can make a tiny bright spot instead of lighting about half of the globe.
- Forgetting to tilt the globe is wrong because Earth is tilted on its axis, and the tilt helps explain changing seasons even though rotation causes day and night.
- Spinning the globe randomly is wrong because Earth rotates from west to east, which is why sunrise appears to happen in the east.
Practice Questions
- 1 If Earth rotates 360 degrees in 24 hours, how many degrees does it rotate in 1 hour?
- 2 If your globe is turned so a city moves from the dark side into the flashlight beam, about what is happening there: sunrise or sunset? If the globe rotates 15 degrees each hour, how many hours does it take to rotate 45 degrees?
- 3 In the globe and flashlight model, why should the flashlight stay in one place while the globe spins?