Astronomy: Day, Night, and Seasons
How Earth's tilt and orbit affect sunlight
Astronomy: Day, Night, and Seasons
How Earth's tilt and orbit affect sunlight
Astronomy - Grade 4-5
- 1
Earth spins once on its axis about every 24 hours. Explain how this spinning causes day and night.
Think about a spinning basketball with a flashlight shining on one side.
Earth's rotation causes day and night. The side of Earth facing the Sun has daytime, and the side turned away from the Sun has nighttime. - 2
Which motion takes about one year: Earth's rotation on its axis or Earth's orbit around the Sun? Explain your answer.
Earth's orbit around the Sun takes about one year. Earth's rotation on its axis takes about one day. - 3
Earth's axis is tilted about 23.5 degrees. Describe what Earth's axis is.
Imagine a line going through the center of a spinning globe.
Earth's axis is an imaginary line that runs from the North Pole to the South Pole. Earth spins around this line. - 4
A student says, "Summer happens because Earth is closer to the Sun." Explain why this idea is not correct.
Think about why the Northern Hemisphere and Southern Hemisphere have opposite seasons.
Summer is not caused by Earth being closer to the Sun. Seasons happen because Earth's axis is tilted, which changes how directly sunlight hits each hemisphere and how long daylight lasts. - 5
When the Northern Hemisphere is tilted toward the Sun, what season does it have? What season does the Southern Hemisphere have?
When the Northern Hemisphere is tilted toward the Sun, it has summer. At the same time, the Southern Hemisphere is tilted away from the Sun, so it has winter. - 6
When a place on Earth rotates from the dark side into the lit side, what part of the day is beginning there?
Think about moving from shadow into light.
Sunrise is beginning there. The place is rotating into the side of Earth that faces the Sun. - 7
Explain why places near the poles can have very long days in summer and very long nights in winter.
Places near the poles have very long days or nights because Earth's tilted axis points one pole more toward the Sun in summer and more away from the Sun in winter. - 8
Fill in the blanks: Earth rotates on its axis once every about ____ hours. Earth orbits the Sun once every about ____ days.
Earth rotates on its axis once every about 24 hours. Earth orbits the Sun once every about 365 days. - 9
Look at the seasons in one hemisphere. Put them in the correct order starting with spring: winter, fall, summer, spring.
Think about the pattern of seasons during one full year.
The correct order starting with spring is spring, summer, fall, winter. - 10
Explain how sunlight is different in summer compared with winter in a hemisphere.
Direct sunlight spreads energy over a smaller area than slanted sunlight.
In summer, sunlight hits the hemisphere more directly and the days are longer. In winter, sunlight is less direct and the days are shorter. - 11
A city has 15 hours of daylight in June and 9 hours of daylight in December. In which month is the city more likely to be having summer? Explain.
The city is more likely to be having summer in June because summer usually has longer daylight hours than winter. - 12
Why do the Northern Hemisphere and Southern Hemisphere have opposite seasons?
Both hemispheres are on the same tilted Earth.
They have opposite seasons because when one hemisphere is tilted toward the Sun, the other hemisphere is tilted away from the Sun. - 13
At noon, the Sun is usually higher in the sky in summer than in winter. How does this affect the temperature of a place?
When the Sun is higher in the sky, its light is more direct and warms the ground more strongly. This helps make summer warmer than winter. - 14
Two students make models with a lamp as the Sun and a globe as Earth. Student A keeps the globe straight up. Student B tilts the globe as it moves around the lamp. Which model better shows the cause of seasons? Explain.
A correct model of seasons must include Earth's tilted axis.
Student B's model better shows the cause of seasons because Earth is tilted as it orbits the Sun. The tilt changes how each hemisphere receives sunlight during the year. - 15
Write one sentence explaining the difference between rotation and revolution in astronomy.
Rotation means an object spins on its axis, while revolution means an object moves in an orbit around another object.