The talk topic is Spiral Galaxies. We brought a variety of models and displays to the expo, reviewed proportions with the calipers, looked for the Golden Ratio in the ant, the zebra and people’s arms and hands. Next we looked at the pieces of Hurricane Sandy which are proportioned to the Golden Ratio. We used a clear spiral to confirm Hurricane Sandy’s golden spiral and then challenged attendees to see if they could find a golden spiral in the picture of Galaxy NGC 1232. Activities: Check arm and hand for golden ratio with calipers, build Hurricane Sandy, build a golden spiral, decorate a golden spiral necklace and check the spiral galaxy for the golden ratio.
To this display I would like to add a small poster card for four ways to find phi. 1. the proportion of a rectangle, 2. the arm to base of five pointed star, 3. ratio of successive Fibonacci numbers and 4. comparing fibonacci (1, x, x+1, 2x+1,…) and geometric sequences (x^0, x^1, x^2, x^3…). I would bring a different picture for the grid. Several people associated the golden proportion with standards of beauty with the mirror/grid, but did not have this connection with the calipers on the arm. We need more variety of photos. Also if I had more space I would have put out a square root spiral and maybe one other or a fibonacci spiral as well for comparison.