As observerd from Earth, the wavelength of H in the spectrum of the star Megrez in the Big Dipper is 486.112 nm.

As observerd from Earth, the wavelength of Hβ in the spectrum of the star Megrez in the Big Dipper is 486.112 nm. Laboratory measurements demonstrate that the normal wavelength of this spectral line is 486.133 nm. Is the star coming toward or moving away from us? At what speed?