The "axis of evil" is a name given to a purported correlation between the plane of the Solar System and aspects of the cosmic microwave background (CMB). Such a correlation would give the plane of the Solar System and hence the location of Earth a greater significance than might be expected by chance, a result which has been claimed to be evidence of a departure from the Copernican principle. However, a 2016 study compared isotropic and anisotropic cosmological models against WMAP and Planck data and found no evidence for anisotropy.