Splashing of liquids: interplay of surrounding gas and surface roughness

We investigate two parameters, gas pressure and substrate roughness, that control the dynamics of splashing when a liquid drop hits a dry solid surface. We associate each of the two distinct forms of splash reported in the literature with one of these parameters: corona splashing is caused by instabilities produced by the pressure of the surrounding gas; prompt splashing is due to surface roughness. The size distribution of ejected droplets reveals the length scales of the underlying droplet-creation process in both cases