It’s Time for Sundial Construction!

Hello, young astronomers and engineers! Today, we’re going to learn about timekeeping and the movement of the sun by constructing our very own sundials. Get ready to explore how ancient civilizations measured time using the sun’s position in the sky!

Introduction to Sundials

Start by discussing the concept of sundials. Read Introduction to Sundials. Learn how ancient civilizations used sundials to tell time based on the position of the sun’s shadow.

Prepare Your Sundial Base

Take your paper plate or cardboard and use the ruler to divide the plate in half. Label the left side of the line at 6am and the right side at 6pm. Use a protractor to divide the top half of the circle into 12 sections. Use a pencil or marker to label each section with the hours of the day, starting from 6 am to 6 pm.

Find True North

If conducting the activity outdoors, use the compass to find the direction of true north. This will help you accurately align your sundial with the sun’s movement.

Insert the Straw or Dowel Rod

Place the straw or dowel rod vertically in the center of your sundial base. This will serve as the gnomon, the part of the sundial that casts a shadow.

Position Your Sundial

If conducting the activity outdoors, position your sundial so that the gnomon is pointing towards true north. If indoors, position it near a window where it will receive direct sunlight throughout the day.

Mark the Shadow

Throughout the day, observe how the shadow cast by the gnomon changes position. Use the small rock or weight to mark the tip of the shadow at different times of the day.

Reflect and Discuss

After observing the sundial throughout the day, gather as a group to reflect on what you’ve learned. Discuss how the position of the sun’s shadow changes over time and how ancient civilizations used sundials to measure time.

The bottom or supporting part of something, often used to provide stability or support for an object.

In the context of a sundial, “casts” refers to the action of creating or producing a shadow on the dial, typically by the gnomon.

A thin, cylindrical piece of wood or metal used for various purposes, such as supporting structures or joining pieces together.

The part of a sundial that casts a shadow onto the dial to indicate the time, usually a thin rod or pointer.

A long, thin, straight piece of material, such as metal or plastic, often used for support or as a tool for measurement.

A dark area or shape formed when an object blocks light from a source, such as the sun, creating a contrast between the illuminated and shaded areas.

A device that measures time by using the position of the sun’s shadow cast by a gnomon onto a dial marked with hours.

In a vertical position or direction, going straight up or down.