diff options
| author | Joseph Hunkeler <jhunkeler@gmail.com> | 2015-03-04 21:21:30 -0500 |
|---|---|---|
| committer | Joseph Hunkeler <jhunkeler@gmail.com> | 2015-03-04 21:21:30 -0500 |
| commit | d54fe7c1f704a63824c5bfa0ece65245572e9b27 (patch) | |
| tree | afc52015ffc2c74e0266653eecef1c8ef8ba5d91 /src/slalib/sun67.htx/node104.html | |
| download | calfuse-d54fe7c1f704a63824c5bfa0ece65245572e9b27.tar.gz | |
Initial commit
Diffstat (limited to 'src/slalib/sun67.htx/node104.html')
| -rw-r--r-- | src/slalib/sun67.htx/node104.html | 208 |
1 files changed, 208 insertions, 0 deletions
diff --git a/src/slalib/sun67.htx/node104.html b/src/slalib/sun67.htx/node104.html new file mode 100644 index 0000000..0a2f9ca --- /dev/null +++ b/src/slalib/sun67.htx/node104.html @@ -0,0 +1,208 @@ +<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2//EN"> +<!--Converted with LaTeX2HTML 97.1 (release) (July 13th, 1997) + by Nikos Drakos (nikos@cbl.leeds.ac.uk), CBLU, University of Leeds +* revised and updated by: Marcus Hennecke, Ross Moore, Herb Swan +* with significant contributions from: + Jens Lippman, Marek Rouchal, Martin Wilck and others --> +<HTML> +<HEAD> +<TITLE>SLA_FK425 - FK4 to FK5</TITLE> +<META NAME="description" CONTENT="SLA_FK425 - FK4 to FK5"> +<META NAME="keywords" CONTENT="sun67"> +<META NAME="resource-type" CONTENT="document"> +<META NAME="distribution" CONTENT="global"> +<META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=iso_8859_1"> +<LINK REL="STYLESHEET" HREF="sun67.css"> +<LINK REL="next" HREF="node105.html"> +<LINK REL="previous" HREF="node103.html"> +<LINK REL="up" HREF="node13.html"> +<LINK REL="next" HREF="node105.html"> +</HEAD> +<BODY > +<BR> <HR> +<A NAME="tex2html1466" HREF="node105.html"> +<IMG WIDTH="37" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="next" SRC="next_motif.gif"></A> +<A NAME="tex2html1464" HREF="node13.html"> +<IMG WIDTH="26" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="up" SRC="up_motif.gif"></A> +<A NAME="tex2html1458" HREF="node103.html"> +<IMG WIDTH="63" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="previous" SRC="previous_motif.gif"></A> <A HREF="sun67.html#stardoccontents"><IMG ALIGN="BOTTOM" BORDER="0" + SRC="contents_motif.gif"></A> +<BR> +<B> Next:</B> <A NAME="tex2html1467" HREF="node105.html">SLA_FK45Z - FK4 to FK5, no P.M. or Parallax</A> +<BR> +<B>Up:</B> <A NAME="tex2html1465" HREF="node13.html">SUBPROGRAM SPECIFICATIONS</A> +<BR> +<B> Previous:</B> <A NAME="tex2html1459" HREF="node103.html">SLA_FITXY - Fit Linear Model to Two Sets</A> +<BR> <HR> <P> +<P><!--End of Navigation Panel--> +<H2><A NAME="SECTION000491000000000000000">SLA_FK425 - FK4 to FK5</A> +<A NAME="xref_SLA_FK425"> </A><A NAME="SLA_FK425"> </A> +</H2> + <DL> +<DT><STRONG>ACTION:</STRONG> +<DD>Convert B1950.0 FK4 star data to J2000.0 FK5. +This routine converts stars from the old, Bessel-Newcomb, FK4 + system to the new, IAU 1976, FK5, Fricke system. The precepts + of Smith <I>et al.</I> (see reference 1) are followed, + using the implementation + by Yallop <I>et al.</I> (reference 2) of a matrix method + due to Standish. + Kinoshita's development of Andoyer's post-Newcomb precession is + used. The numerical constants from + Seidelmann <I>et al.</I> (reference 3) are used canonically. +<P> <DT><STRONG>CALL:</STRONG> +<DD><TT>CALL sla_FK425 ( + R1950,D1950,DR1950,DD1950,P1950,V1950, + R2000,D2000,DR2000,DD2000,P2000,V2000)</TT> +<P> </DL> +<P> <DL> +<DT><STRONG>GIVEN:</STRONG> +<DD> +<BR> +<TABLE CELLPADDING=3> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM>R1950</EM></TD> +<TH ALIGN="LEFT"><B>D</B></TH> +<TD ALIGN="LEFT" NOWRAP>B1950.0 <IMG WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0" + SRC="img24.gif" + ALT="$\alpha$"> (radians)</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM>D1950</EM></TD> +<TD ALIGN="LEFT"><B>D</B></TD> +<TD ALIGN="LEFT" NOWRAP>B1950.0 <IMG WIDTH="10" HEIGHT="13" ALIGN="BOTTOM" BORDER="0" + SRC="img23.gif" + ALT="$\delta$"> (radians)</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM>DR1950</EM></TD> +<TD ALIGN="LEFT"><B>D</B></TD> +<TD ALIGN="LEFT" NOWRAP>B1950.0 proper motion in <IMG WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0" + SRC="img24.gif" + ALT="$\alpha$">(radians per tropical year)</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM>DD1950</EM></TD> +<TD ALIGN="LEFT"><B>D</B></TD> +<TD ALIGN="LEFT" NOWRAP>B1950.0 proper motion in <IMG WIDTH="10" HEIGHT="13" ALIGN="BOTTOM" BORDER="0" + SRC="img23.gif" + ALT="$\delta$">(radians per tropical year)</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM>P1950</EM></TD> +<TD ALIGN="LEFT"><B>D</B></TD> +<TD ALIGN="LEFT" NOWRAP>B1950.0 parallax (arcsec)</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM>V1950</EM></TD> +<TD ALIGN="LEFT"><B>D</B></TD> +<TD ALIGN="LEFT" NOWRAP>B1950.0 radial velocity (km s<SUP>-1</SUP>, +ve = moving away)</TD> +</TR> +</TABLE></DL> +<P> <DL> +<DT><STRONG>RETURNED:</STRONG> +<DD> +<BR> +<TABLE CELLPADDING=3> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM>R2000</EM></TD> +<TH ALIGN="LEFT"><B>D</B></TH> +<TD ALIGN="LEFT" NOWRAP>J2000.0 <IMG WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0" + SRC="img24.gif" + ALT="$\alpha$"> (radians)</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM>D2000</EM></TD> +<TD ALIGN="LEFT"><B>D</B></TD> +<TD ALIGN="LEFT" NOWRAP>J2000.0 <IMG WIDTH="10" HEIGHT="13" ALIGN="BOTTOM" BORDER="0" + SRC="img23.gif" + ALT="$\delta$"> (radians)</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM>DR2000</EM></TD> +<TD ALIGN="LEFT"><B>D</B></TD> +<TD ALIGN="LEFT" NOWRAP>J2000.0 proper motion in <IMG WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0" + SRC="img24.gif" + ALT="$\alpha$">(radians per Julian year)</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM>DD2000</EM></TD> +<TD ALIGN="LEFT"><B>D</B></TD> +<TD ALIGN="LEFT" NOWRAP>J2000.0 proper motion in <IMG WIDTH="10" HEIGHT="13" ALIGN="BOTTOM" BORDER="0" + SRC="img23.gif" + ALT="$\delta$">(radians per Julian year)</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM>P2000</EM></TD> +<TD ALIGN="LEFT"><B>D</B></TD> +<TD ALIGN="LEFT" NOWRAP>J2000.0 parallax (arcsec)</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM>V2000</EM></TD> +<TD ALIGN="LEFT"><B>D</B></TD> +<TD ALIGN="LEFT" NOWRAP>J2000.0 radial velocity (km s<SUP>-1</SUP>, +ve = moving away)</TD> +</TR> +</TABLE></DL> +<P> <DL> +<DT><STRONG>NOTES:</STRONG> +<DD><DL COMPACT> +<DT>1. +<DD>The <IMG WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0" + SRC="img24.gif" + ALT="$\alpha$"> proper motions are <IMG WIDTH="13" HEIGHT="13" ALIGN="BOTTOM" BORDER="0" + SRC="img115.gif" + ALT="$\dot{\alpha}$"> rather than +<IMG WIDTH="48" HEIGHT="13" ALIGN="BOTTOM" BORDER="0" + SRC="img116.gif" + ALT="$\dot{\alpha}\cos\delta$">, and are per year rather than per century. +<DT>2. +<DD>Conversion from Besselian epoch 1950.0 to Julian epoch + 2000.0 only is provided for. Conversions involving other + epochs will require use of the appropriate precession, + proper motion, and E-terms routines before and/or after FK425 + is called. + <DT>3. +<DD>In the FK4 catalogue the proper motions of stars within + <IMG WIDTH="26" HEIGHT="14" ALIGN="BOTTOM" BORDER="0" + SRC="img117.gif" + ALT="$10^{\circ}$"> of the poles do not include the <I>differential + E-terms</I> effect and should, strictly speaking, be handled + in a different manner from stars outside these regions. + However, given the general lack of homogeneity of the star + data available for routine astrometry, the difficulties of + handling positions that may have been determined from + astrometric fields spanning the polar and non-polar regions, + the likelihood that the differential E-terms effect was not + taken into account when allowing for proper motion in past + astrometry, and the undesirability of a discontinuity in + the algorithm, the decision has been made in this routine to + include the effect of differential E-terms on the proper + motions for all stars, whether polar or not. At epoch J2000, + and measuring on the sky rather than in terms of <IMG WIDTH="27" HEIGHT="13" ALIGN="BOTTOM" BORDER="0" + SRC="img118.gif" + ALT="$\Delta\alpha$">, the errors resulting from this simplification are less than + 1 milliarcsecond in position and 1 milliarcsecond per + century in proper motion. + <DT>4. +<DD>See also sla_FK45Z, sla_FK524, sla_FK54Z. + </DL></DL> +<P> <DL> +<DT><STRONG>REFERENCES:</STRONG> +<DD><DL COMPACT> +<DT>1. +<DD>Smith, C.A. <I>et al.</I>, 1989. <I>Astr.J.</I> <B>97</B>, 265. +<DT>2. +<DD>Yallop, B.D. <I>et al.</I>, 1989. <I>Astr.J.</I> <B>97</B>, 274. +<DT>3. +<DD>Seidelmann, P.K. (ed), 1992. <I>Explanatory + Supplement to the Astronomical Almanac,</I> ISBN 0-935702-68-7. + </DL></DL> +<BR> <HR> +<A NAME="tex2html1466" HREF="node105.html"> +<IMG WIDTH="37" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="next" SRC="next_motif.gif"></A> +<A NAME="tex2html1464" HREF="node13.html"> +<IMG WIDTH="26" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="up" SRC="up_motif.gif"></A> +<A NAME="tex2html1458" HREF="node103.html"> +<IMG WIDTH="63" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="previous" SRC="previous_motif.gif"></A> <A HREF="sun67.html#stardoccontents"><IMG ALIGN="BOTTOM" BORDER="0" + SRC="contents_motif.gif"></A> +<BR> +<B> Next:</B> <A NAME="tex2html1467" HREF="node105.html">SLA_FK45Z - FK4 to FK5, no P.M. or Parallax</A> +<BR> +<B>Up:</B> <A NAME="tex2html1465" HREF="node13.html">SUBPROGRAM SPECIFICATIONS</A> +<BR> +<B> Previous:</B> <A NAME="tex2html1459" HREF="node103.html">SLA_FITXY - Fit Linear Model to Two Sets</A> +<BR> <HR> <P> +<P><!--End of Navigation Panel--> +<ADDRESS> +<I>SLALIB --- Positional Astronomy Library<BR>Starlink User Note 67<BR>P. T. Wallace<BR>12 October 1999<BR>E-mail:ptw@star.rl.ac.uk</I> +</ADDRESS> +</BODY> +</HTML> |