  We study conformal invariance of vorticity clusters in weakly compressible
two-dimensional turbulence at low Mach numbers. On the basis of very high
resolution direct numerical simulation we demonstrate the scaling invariance of
the inverse cascade with scaling close to Kolmogorov prediction. In this range
of scales, the statistics of zero-vorticity isolines are found to be compatible
with those of critical percolation, thus generalizing the results obtained in
incompressible Navier-Stokes turbulence.
