Gyroscope precession along unbound equatorial plane orbits around a Kerr   black hole
  The precession of a test gyroscope along unbound equatorial plane geodesic orbits around a Kerr black hole is analyzed with respect to a static reference frame whose axes point towards the "fixed stars." The accumulated precession angle after a complete scattering process is evaluated and compared with the corresponding change in the orbital angle. Limiting results for the non-rotating Schwarzschild black hole case are also discussed. 
Donato Bini, Andrea Geralico, Robert T. Jantzen
gr-qc