  RHIC is the only spin-polarized proton collider ever built. With a special
optics run of $\beta^\star \approx 22$ m STAR detector system is suitable for
an investigation of the spin dependence of elastic proton-proton scattering.
This is a brief summary of measurements of spin asymmetries at the center of
mass energy $\sqrt{s}=200$ GeV and in the four-momentum transfer squared $-t$
range $0.003 < -t < 0.035$ GeV$^2$ by the STAR experiment at RHIC.
