SUBROUTINE iau_PVTOB ( ELONG, PHI, HM, XP, YP, SP, THETA, PV ) *+ * - - - - - - - - - - * i a u _ P V T O B * - - - - - - - - - - * * Position and velocity of a terrestrial observing station. * * This routine is part of the International Astronomical Union's * SOFA (Standards of Fundamental Astronomy) software collection. * * Status: support routine. * * Given: * ELONG d longitude (radians, east +ve, Note 1) * PHI d latitude (geodetic, radians, Note 1) * HM d height above reference ellipsoid (geodetic, m) * XP,YP d coordinates of the pole (radians, Note 2) * SP d the TIO locator s' (radians, Note 2) * THETA d Earth rotation angle (radians, Note 3) * * Returned: * PV d(3,2) position/velocity vector (m, m/s, CIRS) * * Notes: * * 1) The terrestrial coordinates are with respect to the WGS84 * reference ellipsoid. * * 2) XP and YP are the coordinates (in radians) of the Celestial * Intermediate Pole with respect to the International Terrestrial * Reference System (see IERS Conventions 2003), measured along the * meridians 0 and 90 deg west respectively. SP is the TIO locator * s', in radians, which positions the Terrestrial Intermediate * Origin on the equator. For many applications, XP, YP and * (especially) SP can be set to zero. * * 3) If THETA is Greenwich apparent sidereal time instead of Earth * rotation angle, the result is with respect to the true equator * and equinox of date, i.e. with the x-axis at the equinox rather * than the celestial intermediate origin. * * 4) The velocity units are meters per UT1 second, not per SI second. * This is unlikely to have any practical consequences in the modern * era. * * 5) No validation is performed on the arguments. Error cases that * could lead to arithmetic exceptions are trapped by the iau_GD2GC * routine, and the result set to zeros. * * References: * * McCarthy, D. D., Petit, G. (eds.), IERS Conventions (2003), * IERS Technical Note No. 32, BKG (2004) * * Urban, S. & Seidelmann, P. K. (eds), Explanatory Supplement to * the Astronomical Almanac, 3rd ed., University Science Books * (2013), Section 7.4.3.3. * * Called: * iau_GD2GC geodetic to geocentric transformation * iau_POM00 polar motion matrix * iau_TRXP product of transpose of r-matrix and p-vector * * This revision: 2013 June 25 * * SOFA release 2021-05-12 * * Copyright (C) 2021 IAU SOFA Board. See notes at end. * *----------------------------------------------------------------------- IMPLICIT NONE DOUBLE PRECISION ELONG, PHI, HM, XP, YP, SP, THETA, PV(3,2) * Days to seconds DOUBLE PRECISION D2S PARAMETER ( D2S = 86400D0 ) * 2Pi DOUBLE PRECISION D2PI PARAMETER ( D2PI = 6.283185307179586476925287D0 ) * Earth rotation rate in radians per UT1 second DOUBLE PRECISION OM PARAMETER ( OM = 1.00273781191135448D0 * D2PI / D2S ) INTEGER J DOUBLE PRECISION XYZM(3), RPM(3,3), XYZ(3), X, Y, Z, S, C * Geodetic to geocentric transformation (WGS84). CALL iau_GD2GC ( 1, ELONG, PHI, HM, XYZM, J ) * Polar motion and TIO position. CALL iau_POM00 ( XP, YP, SP, RPM ) CALL iau_TRXP ( RPM, XYZM, XYZ ) X = XYZ(1) Y = XYZ(2) Z = XYZ(3) * routines of ERA. S = SIN(THETA) C = COS(THETA) * Position. PV(1,1) = C*X - S*Y PV(2,1) = S*X + C*Y PV(3,1) = Z * Velocity. PV(1,2) = OM * ( -S*X - C*Y ) PV(2,2) = OM * ( C*X - S*Y ) PV(3,2) = 0D0 * Finished. *+---------------------------------------------------------------------- * * Copyright (C) 2021 * Standards Of Fundamental Astronomy Board * of the International Astronomical Union. * * ===================== * SOFA Software License * ===================== * * NOTICE TO USER: * * BY USING THIS SOFTWARE YOU ACCEPT THE FOLLOWING SIX TERMS AND * CONDITIONS WHICH APPLY TO ITS USE. * * 1. The Software is owned by the IAU SOFA Board ("SOFA"). * * 2. Permission is granted to anyone to use the SOFA software for any * purpose, including commercial applications, free of charge and * without payment of royalties, subject to the conditions and * restrictions listed below. * * 3. You (the user) may copy and distribute SOFA source code to others, * and use and adapt its code and algorithms in your own software, * on a world-wide, royalty-free basis. That portion of your * distribution that does not consist of intact and unchanged copies * of SOFA source code files is a "derived work" that must comply * with the following requirements: * * a) Your work shall be marked or carry a statement that it * (i) uses routines and computations derived by you from * software provided by SOFA under license to you; and * (ii) does not itself constitute software provided by and/or * endorsed by SOFA. * * b) The source code of your derived work must contain descriptions * of how the derived work is based upon, contains and/or differs * from the original SOFA software. * * c) The names of all routines in your derived work shall not * include the prefix "iau" or "sofa" or trivial modifications * thereof such as changes of case. * * d) The origin of the SOFA components of your derived work must * not be misrepresented; you must not claim that you wrote the * original software, nor file a patent application for SOFA * software or algorithms embedded in the SOFA software. * * e) These requirements must be reproduced intact in any source * distribution and shall apply to anyone to whom you have * granted a further right to modify the source code of your * derived work. * * Note that, as originally distributed, the SOFA software is * intended to be a definitive implementation of the IAU standards, * and consequently third-party modifications are discouraged. All * variations, no matter how minor, must be explicitly marked as * such, as explained above. * * 4. You shall not cause the SOFA software to be brought into * disrepute, either by misuse, or use for inappropriate tasks, or * by inappropriate modification. * * 5. The SOFA software is provided "as is" and SOFA makes no warranty * as to its use or performance. SOFA does not and cannot warrant * the performance or results which the user may obtain by using the * SOFA software. SOFA makes no warranties, express or implied, as * to non-infringement of third party rights, merchantability, or * fitness for any particular purpose. In no event will SOFA be * liable to the user for any consequential, incidental, or special * damages, including any lost profits or lost savings, even if a * SOFA representative has been advised of such damages, or for any * claim by any third party. * * 6. The provision of any version of the SOFA software under the terms * and conditions specified herein does not imply that future * versions will also be made available under the same terms and * conditions. * * In any published work or commercial product which uses the SOFA * software directly, acknowledgement (see www.iausofa.org) is * appreciated. * * Correspondence concerning SOFA software should be addressed as * follows: * * By email: sofa@ukho.gov.uk * By post: IAU SOFA Center * HM Nautical Almanac Office * UK Hydrographic Office * Admiralty Way, Taunton * Somerset, TA1 2DN * United Kingdom * *----------------------------------------------------------------------- END