Exploration and Observation: Make a Sundial

Lots of attention has been paid to the Mayan calendar lately, but the Mayans actually had many scientific achievements, including astronomy, agriculture, and this week's activity, sundials. Even Max Murphy could handle this one!

This guest post was written by one of my very favorite people, Laura Cotts. Laura has taught math, physics, and astronomy courses and labs at Southern Utah University and gave me my very first job as a TA. (Aww!) But my favorite thing Laura does is an amazing array of science activities and demonstrations each year at a local children's jubilee. Take it away, Laura, and thank you!

What if we had no clocks and no compasses? We could use the sun to help us tell time and to find directions!

We have heard that the sun rises in the east and sets in the west. But does this mean EXACTLY east and west?  And does the sun ALWAYS rise in the same place?

This is a project you can do several times during the year. The most interesting ones to compare are done in December and June, with one more in either September or March.

Here's what you'll need to do to make your sundial:

1. Get a large piece of cardboard or foam board and glue a golf tee, flat side down, near the center.

2. Pick a sunny Saturday or holiday, for you will want to visit your board about once an hour, all day long. Find a place that will be in the sun the whole day and tape your board down so it won't blow away, and so it will always be sitting the same way.

3. Starting early in the morning, go out and look at the shadow of your golf tee. How long is it? In which direction is it pointing? Draw a line along the shadow, to its very end, and beside it write the time. Pay attention to the location of the sun.

4. Visit your board about once every hour and draw a line along the shadow. Has the shadow changed?  If so, how? Where is the sun?

5.  At the end of the day you will have many shadow lines. What pattern do they make? How did they change? When was your shadow line the shortest? The longest? Can you think why?

If your board stayed in the same place, could it help you tell the time on another day? You have made a very simple sundial!

Did your changing shadows sweep along a curve?  Could this be why our round clocks and watches run "clockwise"?

If you set the board out a month or two later, will the shadows match your times again, or will there be a change? The shadows come from the sun--will the sun have changed its path? Try it!

June

It will be the most fun to try this activity again in June.

• Do you think the picture will be the same as December or March?
• How are your June shadows different from the December shadows? 
• How would a March  pattern differ from either? What has caused the changes?
• Does the sun always rise and set in the same places?  What evidence do you have?
• Can the shadow patterns tell us about the different paths that the sun traces across the sky?

Sundials

The sundial you have made would only tell fairly accurate time for a few weeks. As the seasons change the sun's path changes.

Sundials use the shadow of a stick, called a gnomon. To make a more accurate sundial, the gnomon should be at an angle that matches your latitude.

Directions for a simple sundial can be found here. This sundial will tell time most accurately for a mid latitude in March and September.

For more activities with the sun and the seasons, visit here or here. For very complete information on sundials try the British Sundial Society.

Thank you, Laura! I told you she was wonderful. We'd love to have your questions or comments below!

Middleworld by J&P Voelkel

The world is going to end on 12/21/12! Actually, no, it isn't. But the Mayans said it would! Actually, no, they didn't. But still, now is the perfect time for you to read Middleworld (Book 1 of the Jaguar Stones) by husband and wife team J&P Voelkel!

 From Goodreads: An epic adventure that brings together ancient history and modern adolescent angst - as it pits a pampered, pizza-eating, 21st century Boston teenager against the Death Lords of the Maya Underworld. In Book One: "Middleworld," 14-year-old Max Murphy is trying to survive in the perilous rainforest. But poisonous snakes and man-eating jaguars are the least of his problems. It seems the jungle is alive with the spirits of the Ancient Maya. Even worse, his parents have been taken prisoner in the Maya underworld and it's up to him to rescue them. Oh, and - no pressure - but the world will end in five days' time unless Max can win his battle against the villainous Lords of Death. Into this thrilling, and sometimes spine-chilling, adventure story is woven a huge amount of detail about the Maya and life in the rainforest. The authors, have drawn on the latest research to present possibly the most accurate picture of the Maya world in children's literature.

My Two Cents: There is so much action and adventure here it's hard to know where to begin! The setup of this book was great--we grow and learn with Max in a way that doesn't feel forced at all. And the plot is so fast-paced and engaging that kids gobble up the (subtle and well-placed) educational parts as well. In keeping with Mayan culture, there issue of human sacrifice definitely comes up, but of course no humans are sacrificed in our storyline. Note to educators: I've heard that these authors do amazing school visits...

Grade Level: 5-8

Additional Resources:
The Jaguar Stones website, with really outstanding teacher resources that include writing Maya glyphs, Maya math, and a FREE LESSON PLAN CD
A great Mayan Kids site that explores the people, places, and beliefs of Mayan civilization
Howler monkey photos, facts, and videos
The Rainforest Alliance has great games, virtual storybooks, and plant and animal info for kids as well as lesson plans for teachers designed for every grade level.

More to Read:
The beginning of another worldwide adventure series for the same age group: The 39 Clues: The Maze of Bones by Rick Riordan
A series for slightly younger readers about another fun and adventurous boy with the fate of a whole civilization on his shoulders: Elliot and the Goblin War by Jennifer Nielsen
A slightly more sci-fi take on the theme of a boy who solves his family issues, saves a society, and learns a lot about himself in the process: What Came from the Stars by Gary D. Schmidt

The ancient Mayans were a very scientifically advanced culture. Check back Thursday for a science activity that illustrates one of the tools they developed!