Tree-level gluon amplitudes on the celestial sphere

Pasterski, Shao and Strominger have recently proposed that massless scattering amplitudes can be mapped to correlators on the celestial sphere at infinity via a Mellin transform. We apply this prescription to arbitrary n-point tree-level gluon amplitudes. The Mellin transforms of MHV amplitudes are given by generalized hypergeometric functions on the Grassmannian Gr(4,n), while generic non-MHV amplitudes are given by more complicated Gelfand A-hypergeometric functions.