SLA_FK5HZ - FK5 to Hipparcos, no P.M.

From d54fe7c1f704a63824c5bfa0ece65245572e9b27 Mon Sep 17 00:00:00 2001 From: Joseph Hunkeler Date: Wed, 4 Mar 2015 21:21:30 -0500 Subject: Initial commit --- src/slalib/sun67.htx/node109.html | 168 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 168 insertions(+) create mode 100644 src/slalib/sun67.htx/node109.html (limited to 'src/slalib/sun67.htx/node109.html') diff --git a/src/slalib/sun67.htx/node109.html b/src/slalib/sun67.htx/node109.html new file mode 100644 index 0000000..ddda44d --- /dev/null +++ b/src/slalib/sun67.htx/node109.html @@ -0,0 +1,168 @@ + + + + +SLA_FK5HZ - FK5 to Hipparcos, no P.M. + + + + + + + + + + + + +

+ +

+
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+Up: SUBPROGRAM SPECIFICATIONS +
+ Previous: SLA_FK54Z - FK5 to FK4, no P.M. or Parallax +

SLA_FK5HZ - FK5 to Hipparcos, no P.M. + +

ACTION: +: Transform an FK5 (J2000) star position into the frame of the +Hipparcos catalogue, assuming zero Hipparcos proper motion. +
CALL: +: CALL sla_FK52H (R5,D5,EPOCH,RH,DH) +

GIVEN: +

+
+ + + + + + + + + + + + + +

R5	D	J2000.0 FK5 $\alpha$ (radians)
D5	D	J2000.0 FK5 $\delta$ (radians)
EPOCH	D	Julian epoch (TDB)

RETURNED: +

+
+ + + + + + + + + +

RH	D	Hipparcos $\alpha$ (radians)
DH	D	Hipparcos $\delta$ (radians)

NOTES: +

1. +

The $\alpha$ proper motions are $\dot{\alpha}$ rather than + $\dot{\alpha}\cos\delta$ , and are per year rather than per century. +

2. +

The FK5 to Hipparcos + transformation consists of a pure rotation and spin; + zonal errors in the FK5 catalogue are not taken into account. +

3. +

The adopted epoch J2000.0 FK5 to Hipparcos orientation and spin + values are as follows (see reference): +

+
+
+

             + + + + + + + + + + + + + + + + + + + + + +
orientation    spin
x -19.9     -0.30
y -9.1     +0.60
z +22.9     +0.70
mas      mas/y
+

	orientation	spin
x	-19.9	-0.30
y	-9.1	+0.60
z	+22.9	+0.70
	mas	mas/y

+
+
+
+

+These orientation and spin components are interpreted as + axial vectors. An axial vector points at the pole of + the rotation and its length is the amount of rotation in radians. +

4. +

See also sla_FK52H, sla_H2FK5, sla_HFK5Z. +

REFERENCE: +: Feissel, M. & Mignard, F., 1998., Astron.Astrophys. 331, L33-L36. +

+ +

+
+ Next: SLA_FLOTIN - Decode a Real Number +
+Up: SUBPROGRAM SPECIFICATIONS +
+ Previous: SLA_FK54Z - FK5 to FK4, no P.M. or Parallax +

+SLALIB --- Positional Astronomy Library
Starlink User Note 67
P. T. Wallace
12 October 1999
E-mail:ptw@star.rl.ac.uk +

+ + -- cgit