  Whispering gallery modes are known for having orbital angular momentum,
however the interplay of local spin density, orbital angular momentum, and the
near-field interaction with quantum emitters is much less explored. Here, we
study the spin-orbital interaction of a circularly polarized dipole with the
whispering gallery modes (WGMs) of a spherical resonator. Using an exact dyadic
Green's function approach, we show that the near-field interaction between the
photonic spin of a circularly polarized dipole and the local spin density of
whispering gallery modes gives rise to unidirectional behaviour where modes
with either positive or negative orbital angular momentum are excited. We show
that this is a manifestation of spin-momentum locking using the whispering
gallery modes of the spherical resonator. We discuss the requirements for
possible experimental demonstrations using Zeeman transitions in cold atoms or
quantum dots, and outline potential applications of these previously overlooked
properties. Our work firmly establishes local spin density, momentum and decay
as a universal right-handed electromagnetic triplet for evanescent waves.
