One of the main threads of inquiry for the beginning of the Clocks arc for the Hawks has been the ancient timekeeping tool of sundials. The Hawks have approached the sundial in the same way they approached their chairs in the first arc: with a first draft! They came up with their first idea of a sundial as a clock face with a dial (called a gnomon) sticking straight out of the middle. Mackenzie writes, “I may have guided them to a more successful sundial if I hadn’t seen such an incredible math opportunity in the challenge of dividing a circle into twelve equal parts.”
She watched as the group started folding their circles in half, and them half again, coming up with fractions as small as 1/32. They discussed the number pattern, them reevaluated to come up with 1/12 for their clock face.
They started using protractors to make each folded fraction equal. “Soon everyone discovered that each section would have to be 30 degrees,” Mackenzie writes. “After lunch the kids returned to the clocks faces add minutes and mark out hours with numbers and roman numerals.”
After some experimentation, however, the Hawks learned that their first prototype did not work, even despite the cloudy day at the beginning of the week.
Mackenzie writes, “The group discovered that the sun travels from east to west in the south casting a shadow across the upper part of the dial and never the bottom! On Tuesday our second iteration of sundial was a simple board with a stick in it that we would mark on every hour. We would bring the clock to where we found a patch of sun then orient it north and mark the tip of the shadow. We discovered the problem with this method was that the uneven ground was messing up our readings. On Wednesday we traced a place for our sun dial that we could return to every hour.”
The Hawks have asked, “Why do so many sundials have tilted gnomons? What angle should our gnomon be?” They report that they have been google searching, watching videos and making mini-solar system demonstrations to try and understand this. We’re excited to see what they come up with!