The catalytic activity of Pd nanocrystals depends on their crystallographic facets. Thus, knowledge of the surface energies of Pd is required to develop a fundamental understanding of the behaviour of Pd catalysts. Researchers from the Surface Nanoscience group have reported in Appl. Phys. Lett. that the ratio of the surface energies for Pd was determined to be γ111/γ001 = 0.77 ± 0.02. This was done measuring crystal dimensions of equilibrium-shaped Pd crystals grown in ultrahigh vacuum (UHV) from scanning tunnelling microscopy (STM) images. Similar carefully executed experiments could be used to determine the surface energy ratios of other catalytically interesting metals in UHV.