Microtornadoes Under a Crystalline Igloo (image) American Chemical Society Caption Real-world tornadoes form (top) in association with deep moist convection and other atmospheric conditions. As an analogue to that cloud, the image (bottom) shows a nanocrystalline igloo grown from nanospheres in a water drop evaporating from a Petri dish. The circular patterns (arrow) consist of nanospheres arranged by microtornado vortexes. Credit Photos Courtesy of Andrei P. Sommer Usage Restrictions None Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.