FUNCTION THETAG(EP) COMMON /E1/XMO,XNODEO,OMEGAO,EO,XINCL,XNO,XNDT2O,XNDD6O,BSTAR, 1 X,Y,Z,XDOT,YDOT,ZDOT,EPOCH,DS50 DOUBLE PRECISION EPOCH,D,THETA,TWOPI,YR,TEMP,EP,DS50 TWOPI=6.28318530717959D0 YR=(EP+2.D-7)*1.D-3 JY=YR YR=JY D=EP-YR*1.D3 IF(JY.LT.10) JY=JY+80 N=(JY-69)/4 IF(JY.LT.70) N=(JY-72)/4 DS50=7305.D0 + 365.D0*(JY-70) +N + D THETA=1.72944494D0 + 6.3003880987D0*DS50 TEMP=THETA/TWOPI I=TEMP TEMP=I THETAG=THETA-TEMP*TWOPI IF(THETAG.LT.0.D0) THETAG=THETAG+TWOPI RETURN END