Sure, the sun warms the earth and provides us with daylight, but did you know it can also help us tell time? That’s right! Before people had clocks or watches, they told time using sundials—which rely on the sun, shadows, and direction in relation to the Earth’s axis. Now you can make one for yourself.
- Analog (not digital) watch or clock
- Ruler Square of cardboard with sides 12” or longer
- Cardboard paper towel tube
- Tape or hot glue
- Dark-colored marker
What to Do:
1. Place the cardboard in a sunny, flat location in the garden or yard.
2. Use your ruler to find the center of the cardboard square, stand the paper towel tube on one end at the center point, then fasten it in place with tape. (Or, you can do this inside with a hot glue gun, before you head out to the garden.)
3. At noon, look for the shadow on the cardboard and place a thumbtack at the end of the shadow. Use your ruler to help you draw a line between the tube and the thumbtack. This line represents 12:00.
4. Set the timer for an hour. When it goes off, repeat step 3 and draw a new line to mark the new time. Repeat until you have marks for all of the daylight hours.
Be sure to mark the exact position and direction of your sundial if you need to take it inside in case of rain; otherwise, it won’t work when you put it back outside. Interested in creating a more permanent sundial? Experiment with other objects with flat, round tops (like an old terracotta plant saucer or tree stump), along with leftover lumber and some paint. For more sundial activities, ideas, and info, download Telling Time: No Clock Necessary!