What is the minimum height to which a gamma quanta source containing excited Zn67 nuclei has to be raised for the gravitational displacement of the Moss Bauer line to exceed the line width itself, when registered on the Earth's surface? The registered gamma quanta are known to have an energy e = 93 keV and appear on transition of Zn67 nuclei to the ground state, and the mean lifetime of the excited state is τ = 14μs.