It might look like the surface of the Sun, but this is actually the complex simulated fluid dynamics of streamlines in turbulent liquid mercury.
The fine golden lines actually show how liquid mercury moves across the bottom plate of heated cylinder. The motion, known as Rayleigh-Bénard convection, is a result of the distribution of temperature in the metal. Argonne NatLab explains more:
Many turbulent flows found in nature and exploited for heat transfer in technology are driven by sustained temperature differences. Applications range from chip-cooling devices to the study of convection in the sun and Earth’s atmosphere, core, and oceans. Turbulent Rayleigh-Bénard convection (RBC) is a type of heat transfer in which a fluid cell is kept at a constant temperature difference between top and bottom. Because the fluid is confined, thin boundary layers of the temperature and velocity ﬁelds form. To better understand whether heat transport is dominated by these boundary layers and their dynamics, researchers are using leadership-class computing to predict the transition to turbulence in the boundary layers of RBC.
They call it science, I call it art.