On a breezy hilltop, Rocket flies a kite while Raven sits on warm rocks.
"The wind is strong today," Rocket says, holding tight. "Where does wind even come from?"
Raven presses her palms on the sunny rock, then on the shady grass. "What do you notice about how warm they feel?"
Nova floats beside the kite string. "Here is a clue," she says. "Uneven warming makes air move."
The Sun has been producing energy for billions of years. It is the original source of nearly all the energy we use.
The Sun warms Earth's surface unevenly. Land and water heat up at different speeds. That uneven heating causes wind.
Plants use sunlight to grow, so wood holds energy that came from the Sun.
Even coal holds energy that ancient plants stored from sunlight long ago.
Solar cells turn sunlight into electricity. Solar heaters use sunlight to warm water for homes and pools.
Almost every energy path leads back to the Sun.
Sun to plants: plants grow, and wood stores the energy.
Sun to wind: uneven heating makes the air move.
Sun to coal: ancient plants stored sunlight, then became coal over millions of years.
| Statement | True or false? |
|---|---|
| Land and water heat up at different speeds. | ? |
| Wind energy really starts with the Sun. | ? |
| Coal has nothing to do with the Sun. | ? |
| The Sun is the source of nearly all the energy we use. | ? |
What a sunny discovery! Tomorrow at Launch Lab, your family becomes an energy saver team.