thesky_vsop Module Reference

Procedures for VSOP. More...

Functions/Subroutines
subroutine	vsop87d_lbr (tm, pl, lon, lat, rad, lbaccur, raccur)
	Calculate true heliocentric ecliptic coordinates l,b,r for planet pl and the mean ecliptic and equinox of date using VSOP87D.

Detailed Description

Procedures for VSOP.

Note

VSOP87 accuracies 1900-2100 in milliarcseconds (VSOP87 paper):

• Me: 1, Ve: 6, Ea: 5, Ma: 23, Ju: 20, Sa: 100, Ur: 16, Ne: 30

Accuracy < 1" in JD2000 +- range in kyr (Wikipedia): - Me-Ma: 4, Ju,Sa: 2, Ur,Ne: 6 (i.e., Earth position more accurate than 1" between -2000 and +6000)

See also

Bretagnon, P.; Francou, G. Planetary theories in rectangular and spherical variables - VSOP 87 solutions http://esoads.eso.org/abs/1988A%26A...202..309B

Function/Subroutine Documentation

vsop87d_lbr()

subroutine thesky_vsop::vsop87d_lbr	(	real(double), intent(in)	tm,
		integer, intent(in)	pl,
		real(double), intent(out)	lon,
		real(double), intent(out)	lat,
		real(double), intent(out)	rad,
		real(double), intent(in), optional	lbaccur,
		real(double), intent(in), optional	raccur )

Calculate true heliocentric ecliptic coordinates l,b,r for planet pl and the mean ecliptic and equinox of date using VSOP87D.

Parameters

tm	Dynamical time in Julian Millennia after J2000.0, (tau in Meeus)
pl	Planet to compute position for
lon	Heliocentric longitude (rad) (output)
lat	Heliocentric latitude (rad) (output)
rad	Heliocentric distance (AU) (output)
LBaccur	Desired accuracy of L,B (rad, optional)
Raccur	Desired accuracy of R (AU, optional)

See also

http://esoads.eso.org/abs/1988A%26A...202..309B

Definition at line 58 of file vsop.f90.

References thesky_planetdata::vsopdat, thesky_planetdata::vsopnblk, and thesky_planetdata::vsopnls.

Referenced by thesky_comets::cometgc(), and thesky_planets::planet_position().