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    PR # 31059                                                                   
     This is the fourth in the series of proposals to sample over the enti       
     re 162-d precession phases of SS 433 in four years.  The PV and AO-1        
     observations covered the precession phase 0.98 -- 0.30, and AO-2 will       
      cover the phase ~0.5. In AO-3, we proposed to make intensive observa       
     tions at around phase 0.65, when the Doppler shifts of the jets are a       
     t maximum and the relativistic effects are most effective.  We plan t       
     o investigate the systematic velocity difference between the optical        
     and X-ray jets, stability of the X-ray Doppler shifts on a time scale       
      of a day, and resolve the core emission at the base of the jet which       
      can be viewed only at this phase of the largest inclination of the j       
     ets. These are the essential information to understand the accelerati       
    on and energetics of the jet.                                                
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