Procedures for nutation. More...

Functions/Subroutines
subroutine	nutation (t, dpsi, eps0, deps)
	Calculate nutation - cheap routine from Meeus - as well as the mean obliquity of the ecliptic.

subroutine	nutation2000 (jd, dpsi_tot, deps_tot, eps0)
	Compute nutation using the IAU 2000 model. Add the mean obliquity of the ecliptic by Laskar (1986).

subroutine	ls_nut (jd, dpsi_ls, deps_ls)
	Compute the MHB_2000 luni-solar contributions the nutations in longitude and obliquity.

subroutine	ls_angles (epoch, ls_arg)
	compute the value of the fundamental argument for Brown's arguments.

subroutine	eval_ls_nut (epoch, ls_arg, dpsi_ls, deps_ls)
	Compute the nutations in longitude and obliquity by summing over all terms in the nutations series.

subroutine	out_plan_nut ()
	Write the planetary contribution to the nutations to stdout.

subroutine	plan_nut (jd, dpsi, deps)
	Compute the planetary contribution to the nutations.

subroutine	eval_plan_nut (plan_arg, plan_rat, dpsi, deps, out)
	Compute the planetary nutations by summing over the KS1990 coefficients.

subroutine	plan_angles (epoch, plan_arg, plan_rat)
	Compute of planetary arguments for planetary nutation.

subroutine	fcn_nut (jd, dpsi_fcn, deps_fcn)
	Compute the consttributions of the freely excited FCN mode to the nutations in longitude and obliquity.

subroutine	prec_nut (jd, dpsi_prec, deps_prec)
	Evaluate the corrections to the nutations in longitude and obliquity due to the corrections to the IAU-1976 Luni-solar precession constant and the secular rate of change of the obliquity of the ecliptic.

subroutine	ls_iau76 (epoch, ls_arg)
	Compute the value of the fundamental argument for Brown's arguments.

Detailed Description

Procedures for nutation.

Function/Subroutine Documentation

◆ eval_ls_nut()

subroutine thesky_nutation::eval_ls_nut	(	real(double), intent(in)	epoch,
		real(double), dimension(5), intent(in)	ls_arg,
		real(double), intent(out)	dpsi_ls,
		real(double), intent(out)	deps_ls )

Compute the nutations in longitude and obliquity by summing over all terms in the nutations series.

Parameters

epoch	Julian day for arguments (input)
ls_arg	Brown's arguments (input; rad)
dpsi_ls	Nutation in longitude (output; milliarcsec)
deps_ls	Nutation in obliquity (output; milliarcsec)

Definition at line 520 of file nutation.f90.

Referenced by ls_nut().

◆ eval_plan_nut()

subroutine thesky_nutation::eval_plan_nut	(	real(double), dimension(14), intent(in)	plan_arg,
		real(double), dimension(14), intent(in)	plan_rat,
		real(double), intent(out)	dpsi,
		real(double), intent(out)	deps,
		character, dimension(*), intent(in)	out )

Compute the planetary nutations by summing over the KS1990 coefficients.

Parameters

plan_arg	Planetary arguments including pa as given (KS1990) (input; rad)
plan_rat	Planetary argument rates (input; rad/yr)
dpsi	Contribution to nutations in longitude (output; mas)
deps	Contribution to nutations in obliquity (output; mas)
out	'YES' to write data to stdout (input)

Definition at line 1572 of file nutation.f90.

Referenced by out_plan_nut(), and plan_nut().

◆ fcn_nut()

subroutine thesky_nutation::fcn_nut	(	real(double), intent(in)	jd,
		real(double), intent(out)	dpsi_fcn,
		real(double), intent(out)	deps_fcn )

Compute the consttributions of the freely excited FCN mode to the nutations in longitude and obliquity.

Parameters

jd	Julian day (input)
dpsi_fcn	Contribution to the nutation in longitude (output; milliarcsec)
deps_fcn	Contribution to the nutation in obliquity (output; milliarcsec)

Definition at line 2701 of file nutation.f90.

Referenced by nutation2000().

◆ ls_angles()

subroutine thesky_nutation::ls_angles	(	real(double), intent(in)	epoch,
		real(double), dimension(5), intent(out)	ls_arg )

compute the value of the fundamental argument for Brown's arguments.

Parameters

epoch	Julian day for arguments (input)
ls_arg	Brown's arguments (rad)

Definition at line 382 of file nutation.f90.

Referenced by ls_nut().

◆ ls_iau76()

subroutine thesky_nutation::ls_iau76	(	real(double), intent(in)	epoch,
		real(double), dimension(5), intent(out)	ls_arg )

Compute the value of the fundamental argument for Brown's arguments.

Parameters

epoch	Julian day (input)
ls_arg	Brown's arguments (output; rad)

Definition at line 2990 of file nutation.f90.

◆ ls_nut()

subroutine thesky_nutation::ls_nut	(	real(double), intent(in)	jd,
		real(double), intent(out)	dpsi_ls,
		real(double), intent(out)	deps_ls )

Compute the MHB_2000 luni-solar contributions the nutations in longitude and obliquity.

Parameters

jd	Julian day
dpsi_ls	Nutation in longitude (milliarcsec)
deps_ls	Nutation in obliquity (milliarcsec)

Definition at line 239 of file nutation.f90.

References eval_ls_nut(), and ls_angles().

Referenced by nutation2000().

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◆ nutation()

subroutine thesky_nutation::nutation	(	real(double), intent(in)	t,
		real(double), intent(out)	dpsi,
		real(double), intent(out)	eps0,
		real(double), intent(out)	deps )

Calculate nutation - cheap routine from Meeus - as well as the mean obliquity of the ecliptic.

Parameters

t	Time in Julian Millennia since 2000.0 in dynamical time
dpsi	Nutation in longitude (output)
eps0	Obliquity of the ecliptic (output)
deps	Nutation in obliquity (output)

See also

IAU 1980 nutation model: Seidelmann (1981);
Abbreviated by Meeus, Astronomical Algorithms, 1998, Ch. 22.

Definition at line 45 of file nutation.f90.

References thesky_constants::nutationdat.

Referenced by thesky_coordinates::aberration_eq(), thesky_stars::calcstars(), thesky_coordinates::calcsunxyz(), thesky_comets::cometgc(), thesky_comets::cometxyz(), and thesky_planets::planet_position().

◆ nutation2000()

subroutine thesky_nutation::nutation2000	(	real(double), intent(in)	jd,
		real(double), intent(out)	dpsi_tot,
		real(double), intent(out)	deps_tot,
		real(double), intent(out), optional	eps0 )

Compute nutation using the IAU 2000 model. Add the mean obliquity of the ecliptic by Laskar (1986).

Parameters

jd	Julian day of computation
dpsi_tot	Total nutation in longitude (rad)
deps_tot	Total nutation in obliquity (rad)
eps0	Mean obliquity of the ecliptic (rad; optional)

See also: http://geoweb.mit.edu/~tah/mhb2000/

Definition at line 101 of file nutation.f90.

References fcn_nut(), ls_nut(), plan_nut(), and prec_nut().

Referenced by thesky_planets::planet_position().

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◆ out_plan_nut()

subroutine thesky_nutation::out_plan_nut

Write the planetary contribution to the nutations to stdout.

Definition at line 1398 of file nutation.f90.

References eval_plan_nut(), and plan_angles().

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◆ plan_angles()

subroutine thesky_nutation::plan_angles	(	real(double), intent(in)	epoch,
		real(double), dimension(14), intent(out)	plan_arg,
		real(double), dimension(14), intent(out)	plan_rat )

Compute of planetary arguments for planetary nutation.

Parameters

epoch	Julian day (input)
plan_arg	Planetary arguments for longtitudes of L, L', F, D, Om, Mercury, Ven, Ear, Mar, Jup, Sat, Ura, Ura(?), pa.
plan_rat	Planetary argument rates (rads/year)

Definition at line 2530 of file nutation.f90.

Referenced by out_plan_nut(), and plan_nut().

◆ plan_nut()

subroutine thesky_nutation::plan_nut	(	real(double), intent(in)	jd,
		real(double), intent(out)	dpsi,
		real(double), intent(out)	deps )

Compute the planetary contribution to the nutations.

Parameters

jd	Julian day (input)
dpsi	Contribution to the nutation in longitude (output; mas)
deps	Contribution to the nutation in obliquity (output; mas)

Definition at line 1465 of file nutation.f90.

References eval_plan_nut(), and plan_angles().

Referenced by nutation2000().

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◆ prec_nut()

subroutine thesky_nutation::prec_nut	(	real(double), intent(in)	jd,
		real(double), intent(out)	dpsi_prec,
		real(double), intent(out)	deps_prec )

Evaluate the corrections to the nutations in longitude and obliquity due to the corrections to the IAU-1976 Luni-solar precession constant and the secular rate of change of the obliquity of the ecliptic.

Parameters

jd	Julian day (input)
dpsi_prec	Contribution to the nutation in longitude (output; mas)
deps_prec	Contribution to the nutation in obliquity (output; mas)

Definition at line 2892 of file nutation.f90.

Referenced by nutation2000().

Functions/Subroutines

Detailed Description

Function/Subroutine Documentation

◆ eval_ls_nut()

◆ eval_plan_nut()

◆ fcn_nut()

◆ ls_angles()

◆ ls_iau76()

◆ ls_nut()

◆ nutation()

◆ nutation2000()

◆ out_plan_nut()

◆ plan_angles()

◆ plan_nut()

◆ prec_nut()