  We show that the neutrino chirality flip, that can take place in the core of
a neutron star at birth, is an efficient process to allow neutrinos to
anisotropically escape, thus providing a to induce the neutron star kick
velocities. The process is not subject to the {\it no-go theorem} since
although the flip from left- to right-handed neutrinos happens at equilibrium,
the reverse process does not take place given that right-handed neutrinos do
not interact with matter and therefore detailed balance is lost. For
simplicity, we model the neutron star core as being made of strange quark
matter. We find that the process is efficient when the neutrino magnetic moment
is not smaller than $4.7 \times 10^{-15}\mu_B$, where $\mu_B$ is the Bohr
magneton. When this lower bound is combined with the most stringent upper
bound, that uses the luminosity data obtained from the analysis of SN 1987A,
our results set a range for the neutrino magnetic moment given by $4.7 \times
10^{-15} \leq \mu_\nu/\mu_B \leq (0.1 - 0.4)\times 10^{-11}$. The obtained kick
velocities for natal conditions are consistent with the observed ones and span
the correct range of radii for typical magnetic field intensities.
