SIOUX CITY (KTIV) – This episode is about the seasons. We will use light and a polystyrene ball to model the trajectory of our planet around the sun.
Download the experiment instructions HERE!
Let’s model the Earth and how it moves around the sun, creating the seasons.
The Earth’s axis is tilted, 23.5 degrees to be exact. We maintain this tilt as our planet orbits the sun.
The autumnal equinox and spring equinox, also called the first day of autumn and spring respectively, occur when the center of the sun is positioned directly above the equator. So all regions of the Earth receive about 12 hours of daylight.
The summer solstice, or first day of summer, is when the center of the sun is directly above the Tropic of Cancer. So the Northern Hemisphere has longer days, with the Arctic Circle seeing 24 hours of daylight, while the Southern Hemisphere has short days, with the Antarctic Circle seeing zero hours of daylight.
The winter solstice, the first day of winter, occurs when the center of the sun is directly above the Tropic of Capricorn. This time around, the Southern Hemisphere has longer days, the Antarctic Circle has 24 hours of daylight, and the Northern Hemisphere has shorter days, with the Arctic Circle having no hours of daylight.
Note that the distance between the earth and the sun has not changed. How we get the seasons depends on the tilt of the earth!
Watch the video above for a look at the full explanation.
Send photos or videos of your participating students to connect@ktiv.com.
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