42 double dPsi_2000,
double dEps_2000,
double& diffPsi,
double& diffEps)
44 double const sineps0(0.3977771559319137), coseps0(0.9174820620691818);
45 double dPsi_model, dEps_model, dt, dt2, dt3, psi_A, chi_A, f;
46 dPsi_model = (dPsi_2000 - dPsi_1980)*
RAD2MAS;
47 dEps_model = (dEps_2000 - dEps_1980)*
RAD2MAS;
48 dt = (epoch -
tEphem)/36525.0;
53 psi_A = (5038.47875*dt - 1.07259*dt2 -0.001147*dt3)*
SEC2RAD;
55 chi_A = ( 10.5526 *dt - 2.38064*dt2 -0.001125*dt3)*
SEC2RAD;
56 f = (psi_A*coseps0 - chi_A)*(psi_A*coseps0 - chi_A);
59 diffPsi = (-dX + (psi_A*coseps0 - chi_A)*dY)/(-f*sineps0 - sineps0) + dPsi_model;
60 diffEps = (-(psi_A*coseps0 - chi_A)*sineps0*dX - sineps0*dY)/(-f*sineps0 - sineps0) + dEps_model;
62 diffPsi+= (-2.9965)*dt*100.0;
63 diffEps+= (-0.2524)*dt*100.0;
65 diffPsi+= - 41.7750 + 40.0e-3;
66 diffEps+= - 6.8192 - 40.0e-3;
void calcCip2IAU1980(const SgMJD &epoch, double dX, double dY, double dPsi_1980, double dEps_1980, double dPsi_2000, double dEps_2000, double &diffPsi, double &diffEps)
const SgMJD tEphem(51544.5)
#define RAD2MAS
radians to ms:
#define SEC2RAD
radians to arc seconds: