1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
|
SUBROUTINE slMAP (RM, DM, PR, PD, PX, RV, EQ, DATE, RA, DA)
*+
* - - - -
* M A P
* - - - -
*
* Transform star RA,Dec from mean place to geocentric apparent
*
* The reference frames and timescales used are post IAU 1976.
*
* References:
* 1984 Astronomical Almanac, pp B39-B41.
* (also Lederle & Schwan, Astron. Astrophys. 134,
* 1-6, 1984)
*
* Given:
* RM,DM dp mean RA,Dec (rad)
* PR,PD dp proper motions: RA,Dec changes per Julian year
* PX dp parallax (arcsec)
* RV dp radial velocity (km/sec, +ve if receding)
* EQ dp epoch and equinox of star data (Julian)
* DATE dp TDB for apparent place (JD-2400000.5)
*
* Returned:
* RA,DA dp apparent RA,Dec (rad)
*
* Called:
* slMAPA star-independent parameters
* slMAPQ quick mean to apparent
*
* Notes:
*
* 1) EQ is the Julian epoch specifying both the reference frame and
* the epoch of the position - usually 2000. For positions where
* the epoch and equinox are different, use the routine slPM to
* apply proper motion corrections before using this routine.
*
* 2) The distinction between the required TDB and TT is always
* negligible. Moreover, for all but the most critical
* applications UTC is adequate.
*
* 3) The proper motions in RA are dRA/dt rather than cos(Dec)*dRA/dt.
*
* 4) This routine may be wasteful for some applications because it
* recomputes the Earth position/velocity and the precession-
* nutation matrix each time, and because it allows for parallax
* and proper motion. Where multiple transformations are to be
* carried out for one epoch, a faster method is to call the
* slMAPA routine once and then either the slMAPQ routine
* (which includes parallax and proper motion) or slMAPZ (which
* assumes zero parallax and proper motion).
*
* 5) The accuracy is sub-milliarcsecond, limited by the
* precession-nutation model (IAU 1976 precession, Shirai &
* Fukushima 2001 forced nutation and precession corrections).
*
* 6) The accuracy is further limited by the routine slEVP, called
* by slMAPA, which computes the Earth position and velocity
* using the methods of Stumpff. The maximum error is about
* 0.3 mas.
*
* P.T.Wallace Starlink 17 September 2001
*
* Copyright (C) 2001 Rutherford Appleton Laboratory
*
* License:
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program (see SLA_CONDITIONS); if not, write to the
* Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
* Boston, MA 02110-1301 USA
*
* Copyright (C) 1995 Association of Universities for Research in Astronomy Inc.
*-
IMPLICIT NONE
DOUBLE PRECISION RM,DM,PR,PD,PX,RV,EQ,DATE,RA,DA
DOUBLE PRECISION AMPRMS(21)
* Star-independent parameters
CALL slMAPA(EQ,DATE,AMPRMS)
* Mean to apparent
CALL slMAPQ(RM,DM,PR,PD,PX,RV,AMPRMS,RA,DA)
END
|
