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diff --git a/src/slalib/sun67.htx/node126.html b/src/slalib/sun67.htx/node126.html new file mode 100644 index 0000000..abe5fb6 --- /dev/null +++ b/src/slalib/sun67.htx/node126.html @@ -0,0 +1,157 @@ +<!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_MAP - Mean to Apparent</TITLE> +<META NAME="description" CONTENT="SLA_MAP - Mean to Apparent"> +<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="node127.html"> +<LINK REL="previous" HREF="node125.html"> +<LINK REL="up" HREF="node13.html"> +<LINK REL="next" HREF="node127.html"> +</HEAD> +<BODY > +<BR> <HR> +<A NAME="tex2html1686" HREF="node127.html"> +<IMG WIDTH="37" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="next" SRC="next_motif.gif"></A> +<A NAME="tex2html1684" HREF="node13.html"> +<IMG WIDTH="26" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="up" SRC="up_motif.gif"></A> +<A NAME="tex2html1678" HREF="node125.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="tex2html1687" HREF="node127.html">SLA_MAPPA - Mean to Apparent Parameters</A> +<BR> +<B>Up:</B> <A NAME="tex2html1685" HREF="node13.html">SUBPROGRAM SPECIFICATIONS</A> +<BR> +<B> Previous:</B> <A NAME="tex2html1679" HREF="node125.html">SLA_M2AV - Rotation Matrix to Axial Vector</A> +<BR> <HR> <P> +<P><!--End of Navigation Panel--> +<H2><A NAME="SECTION0004113000000000000000">SLA_MAP - Mean to Apparent</A> +<A NAME="xref_SLA_MAP"> </A><A NAME="SLA_MAP"> </A> +</H2> + <DL> +<DT><STRONG>ACTION:</STRONG> +<DD>Transform star <IMG WIDTH="42" HEIGHT="29" ALIGN="MIDDLE" BORDER="0" + SRC="img3.gif" + ALT="$[\,\alpha,\delta\,]$"> from mean place to geocentric apparent. +The reference frames and timescales used are post IAU 1976. +<P> <DT><STRONG>CALL:</STRONG> +<DD><TT>CALL sla_MAP (RM, DM, PR, PD, PX, RV, EQ, DATE, RA, DA)</TT> +<P> </DL> +<P> <DL> +<DT><STRONG>GIVEN:</STRONG> +<DD> +<BR> +<TABLE CELLPADDING=3> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM>RM,DM</EM></TD> +<TH ALIGN="LEFT"><B>D</B></TH> +<TD ALIGN="LEFT" NOWRAP>mean <IMG WIDTH="42" HEIGHT="29" ALIGN="MIDDLE" BORDER="0" + SRC="img3.gif" + ALT="$[\,\alpha,\delta\,]$"> (radians)</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM>PR,PD</EM></TD> +<TD ALIGN="LEFT"><B>D</B></TD> +<TD ALIGN="LEFT" NOWRAP>proper motions: <IMG WIDTH="42" HEIGHT="29" ALIGN="MIDDLE" BORDER="0" + SRC="img3.gif" + ALT="$[\,\alpha,\delta\,]$"> changes per Julian year</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM>PX</EM></TD> +<TD ALIGN="LEFT"><B>D</B></TD> +<TD ALIGN="LEFT" NOWRAP>parallax (arcsec)</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM>RV</EM></TD> +<TD ALIGN="LEFT"><B>D</B></TD> +<TD ALIGN="LEFT" NOWRAP>radial velocity (km s<SUP>-1</SUP>, +ve if receding)</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM>EQ</EM></TD> +<TD ALIGN="LEFT"><B>D</B></TD> +<TD ALIGN="LEFT" NOWRAP>epoch and equinox of star data (Julian)</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM>DATE</EM></TD> +<TD ALIGN="LEFT"><B>D</B></TD> +<TD ALIGN="LEFT" NOWRAP>TDB for apparent place (JD-2400000.5)</TD> +</TR> +</TABLE></DL> +<P> <DL> +<DT><STRONG>RETURNED:</STRONG> +<DD> +<BR> +<TABLE CELLPADDING=3> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM>RA,DA</EM></TD> +<TH ALIGN="LEFT"><B>D</B></TH> +<TD ALIGN="LEFT" NOWRAP>apparent <IMG WIDTH="42" HEIGHT="29" ALIGN="MIDDLE" BORDER="0" + SRC="img3.gif" + ALT="$[\,\alpha,\delta\,]$"> (radians)</TD> +</TR> +</TABLE></DL> +<P> <DL> +<DT><STRONG>NOTES:</STRONG> +<DD><DL COMPACT> +<DT>1. +<DD>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 sla_PM to apply proper + motion corrections before using this routine. + <DT>2. +<DD>The distinction between the required TDB and TT is + always negligible. Moreover, for all but the most + critical applications UTC is adequate. + <DT>3. +<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>4. +<DD>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 sla_MAPPA routine + once and then either the sla_MAPQK routine (which includes + parallax and proper motion) or sla_MAPQKZ (which assumes + zero parallax and FK5 proper motion). + </DL></DL> +<P> <DL> +<DT><STRONG>REFERENCES:</STRONG> +<DD><DL COMPACT> +<DT>1. +<DD>1984 <I>Astronomical Almanac</I>, pp B39-B41. +<DT>2. +<DD>Lederle & Schwan, 1984. <I>Astr.Astrophys.</I> <B>134</B>, 1-6. +</DL></DL> +<BR> <HR> +<A NAME="tex2html1686" HREF="node127.html"> +<IMG WIDTH="37" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="next" SRC="next_motif.gif"></A> +<A NAME="tex2html1684" HREF="node13.html"> +<IMG WIDTH="26" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="up" SRC="up_motif.gif"></A> +<A NAME="tex2html1678" HREF="node125.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="tex2html1687" HREF="node127.html">SLA_MAPPA - Mean to Apparent Parameters</A> +<BR> +<B>Up:</B> <A NAME="tex2html1685" HREF="node13.html">SUBPROGRAM SPECIFICATIONS</A> +<BR> +<B> Previous:</B> <A NAME="tex2html1679" HREF="node125.html">SLA_M2AV - Rotation Matrix to Axial Vector</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> |