A buoyantplume of smoke rises from a stick of incense. At first the plume is smooth and laminar, but even in quiescent air, tiny perturbations can sneak into the flow, causing the periodic vortical whorls seen near the top of the photo. Were the frame even taller, we would see this transitional flow become completely chaotic and turbulent. Despite having known the governing equations for such flow for over 150 years, it remains almost impossible to predict the point where flow will transition for any practical problem, largely because the equations are so sensitive to initial conditions. In fact, some of the fundamental mathematical properties of those equations remain unproven. (Photo credit: M. Rosic)
The folks at io9 have some excellent/terrifying news for H.P. Lovecraft fans: Scientists have just discovered (mini) Cthulhu, in the form of two octopus like protists that live in the stomachs of wood-digesting protists. Meet Cthulhu macrofasciculumque and Cthylla microfasciculumque.