In this paper we report a clustering analysis of upper main-sequence stars in the Small Magellanic Cloud , using data from the VMC survey ( the VISTA near-infrared YJK _ { s } survey of the Magellanic system ) .
Young stellar structures are identified as surface overdensities on a range of significance levels .
They are found to be organized in a hierarchical pattern , such that larger structures at lower significance levels contain smaller ones at higher significance levels .
They have very irregular morphologies , with a perimeter–area dimension of 1.44 \pm 0.02 for their projected boundaries .
They have a power-law mass–size relation , power-law size/mass distributions , and a lognormal surface density distribution .
We derive a projected fractal dimension of 1.48 \pm 0.03 from the mass–size relation , or of 1.4 \pm 0.1 from the size distribution , reflecting significant lumpiness of the young stellar structures .
These properties are remarkably similar to those of a turbulent interstellar medium ( ISM ) , supporting a scenario of hierarchical star formation regulated by supersonic turbulence .