Gravity and light reveal how liquids turn into thin fibers

From spiders spinning their webs to the manufacturing of textiles, the formation of fibers from liquids plays an important role in both nature and industry. Yet accurately predicting the properties of such fibers remains a challenge. The fiber is often much thinner than the nozzle from which a polymer or solution is extruded. Factors such as temperature, flow conditions and chemical reactions ultimately determine a fiber's thickness and strength.