Air DandelionAanika OkaAward: Top 100
School: lenape middle school This photo was taken outside when I went hiking with my family. As I watched the dandelion seeds float like parachutes as my sister blew on them, I could not help but notice this peculiar phenomenon where each dandelion seed is fastened by a thin tube to hundreds of bristles forming parachute like structures which catch the wind when released from the flower head and can float hundreds of miles. While walking around the same area yesterday, as we tried to blow on similar dandelions, they would not budge because they had closed their hairy parachutes due to the rain from previous days. In order to facilitate fertilization in rather windy and dry conditions, the dandelions widen their parachutes to enable long distance flights. This "Air Dandelion" works using fluid dynamics of air flow around the seed to facilitate its long-distance flight. The center of the parachute senses the humidity of its surrounding and responds to the humidity signal by deciding to either open the parachute and become airborne or to close the parachute and stay on the runway essentially waiting for better air quality for take-off. 
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