Researchers have explored properties of turbulence in two important situations: (Left) A layer of fluid of thickness under the influence of gravity is heated from below, so that the temperature is higher than the temperature at the top (Rayleigh-Bénard case). When the temperature difference is sufficiently large, a transition from the state of pure heat conduction to a state of convection occurs. He et al.’s experiment  focuses on the asymptotic state of highly turbulent convection. (Right) In a Taylor-Couette system, a fluid fills the gap between coaxial cylinders with radii and , , which rotate independently with the angular velocities and , respectively. At high enough rotation differential, , a transition from the purely cylindrical flow to axially symmetric Taylor vortices occurs. The latter become turbulent at much higher values of , which is the regime investigated in Huisman et al.’s experiment .