The Sun

The Sun’s regular movement enabled people to determine the time based on the shadows that were cast during various times throughout the day. Sundials are instruments that are used to tell time.

The sundial consists of a triangular central piece (gnomon), which casts a shadow on a numbered scale of hours. The numbers are placed closer together towards noon, and farther apart towards morning and evening, because the shadow moves more slowly over the sundial at midday when the sun is overhead.

Vocabulary:

Sundial: a device that uses shadow to tell time.

Questions:

1. How are people able to determine time based on shadows?

2. What are instruments that are used to tell time?

3. What is the triangular central piece in the sundial referred to?

4. Tell two new pieces of info that you learned from the links provided concerning this topic. Insert these into your defense log.