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SUBROUTINE sla_PVOBS (P, H, STL, PV)
*+
* - - - - - -
* P V O B S
* - - - - - -
*
* Position and velocity of an observing station (double precision)
*
* Given:
* P dp latitude (geodetic, radians)
* H dp height above reference spheroid (geodetic, metres)
* STL dp local apparent sidereal time (radians)
*
* Returned:
* PV dp(6) position/velocity 6-vector (AU, AU/s, true equator
* and equinox of date)
*
* Called: sla_GEOC
*
* IAU 1976 constants are used.
*
* P.T.Wallace Starlink 14 November 1994
*
* Copyright (C) 1995 Rutherford Appleton Laboratory
*-
IMPLICIT NONE
DOUBLE PRECISION P,H,STL,PV(6)
DOUBLE PRECISION R,Z,S,C,V
* Mean sidereal rate (at J2000) in radians per (UT1) second
DOUBLE PRECISION SR
PARAMETER (SR=7.292115855306589D-5)
* Geodetic to geocentric conversion
CALL sla_GEOC(P,H,R,Z)
* Functions of ST
S=SIN(STL)
C=COS(STL)
* Speed
V=SR*R
* Position
PV(1)=R*C
PV(2)=R*S
PV(3)=Z
* Velocity
PV(4)=-V*S
PV(5)=V*C
PV(6)=0D0
END
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