Okay, it’s fall, and dandelions are just one of the many glorious summer plants we won’t see for another eight months. Or maybe ever.
Researchers at the University of Edinburgh decided to investigate the wondrous dandelion seed, the little floating puffy parachutes that spread dandelions up to a mile just on the power of wind. What they found was something never seen before in nature, according to their release.
Dandelion seeds are shaped kind of like an open umbrella, without the actual umbrella webbing; just an array of spines. They’re extremely light, which helps with drifting through the air, but the fact that the tops are so open is curious; surely a solid top, like a parachute, would help keep them aloft, no?
By setting up a tiny, delicate wind tunnel and carefully mapping the precise movement of air around the dandelion seeds, the researchers figured out what’s going on. The precise patterns of the little spines encouraged air flowing upwards—as the seed falls downwards—to create a tiny vortex of swirling air right on top of the seed. That vortex creates a little pocket of low air pressure, which helps to keep the seeds drifting through the air for much longer than it seems like they should.
The researchers say this design is up to four times more efficient than a typical parachute design, so you can count on lots of engineers trying to figure out how to use dandelion-like structures in drones, planes, parachutes, who knows what else. From the release: “Researchers suggest that the dandelion’s porous parachute might inspire the development of small-scale drones that require little or no power consumption. Such drones could be useful for remote sensing or air pollution monitoring.”
Having never found anything quite like this vortex before, the researchers go to name it. They went with “separated vortex ring.”