Sundial

High school (ages 12+)
History & Culture

Name:

Date:

Step 1 · Read the article

Open the article and read it at the level above. Then answer the questions below in your own words.

https://smallwhale.org/articles/sundial

Write what each word means, using the article.

Do not copy the article. Write two things you learned, the way you would explain them to a friend.

Answers below are taken from the article’s stored facts, so they match what the student read.

1. What is the historical significance?Represents a foundational development in metrology and observational astronomy
2. What is the key astronomical principles utilized?Earth's axial rotation, apparent solar motion, latitude, declination, equation of time
3. What is a sundial and how does it tell time?A sundial uses the sun’s shadow to show the time. A fixed stick called a gnomon casts a shadow on a marked surface, and the shadow’s position shows the hour.
4. Why did ancient people use sundials instead of clocks?Sundials were the first way people could measure time before mechanical clocks existed. They used the predictable movement of the sun across the sky to keep track of hours.

Gnomon: The part of a sundial that projects and casts a shadow, typically aligned with the Earth's axis.
Apparent Solar Time: Time as indicated by the sun's position in the sky, which varies slightly throughout the year.
Equation of Time: The difference between apparent solar time and mean solar time, caused by Earth's elliptical orbit and axial tilt.
Metrology: The scientific study of measurement.