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diff --git a/src/slalib/sun67.htx/node127.html b/src/slalib/sun67.htx/node127.html new file mode 100644 index 0000000..6ed5222 --- /dev/null +++ b/src/slalib/sun67.htx/node127.html @@ -0,0 +1,159 @@ +<!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_MAPPA - Mean to Apparent Parameters</TITLE> +<META NAME="description" CONTENT="SLA_MAPPA - Mean to Apparent Parameters"> +<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="node128.html"> +<LINK REL="previous" HREF="node126.html"> +<LINK REL="up" HREF="node13.html"> +<LINK REL="next" HREF="node128.html"> +</HEAD> +<BODY > +<BR> <HR> +<A NAME="tex2html1696" HREF="node128.html"> +<IMG WIDTH="37" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="next" SRC="next_motif.gif"></A> +<A NAME="tex2html1694" HREF="node13.html"> +<IMG WIDTH="26" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="up" SRC="up_motif.gif"></A> +<A NAME="tex2html1688" HREF="node126.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="tex2html1697" HREF="node128.html">SLA_MAPQK - Quick Mean to Apparent</A> +<BR> +<B>Up:</B> <A NAME="tex2html1695" HREF="node13.html">SUBPROGRAM SPECIFICATIONS</A> +<BR> +<B> Previous:</B> <A NAME="tex2html1689" HREF="node126.html">SLA_MAP - Mean to Apparent</A> +<BR> <HR> <P> +<P><!--End of Navigation Panel--> +<H2><A NAME="SECTION0004114000000000000000">SLA_MAPPA - Mean to Apparent Parameters</A> +<A NAME="xref_SLA_MAPPA"> </A><A NAME="SLA_MAPPA"> </A> +</H2> + <DL> +<DT><STRONG>ACTION:</STRONG> +<DD>Compute star-independent parameters in preparation for +conversions between mean place and geocentric apparent place. + The parameters produced by this routine are required in the + parallax, light deflection, aberration, and precession/nutation + parts of the mean/apparent transformations. + The reference frames and timescales used are post IAU 1976. +<P> <DT><STRONG>CALL:</STRONG> +<DD><TT>CALL sla_MAPPA (EQ, DATE, AMPRMS)</TT> +<P> </DL> +<P> <DL> +<DT><STRONG>GIVEN:</STRONG> +<DD> +<BR> +<TABLE CELLPADDING=3> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM>EQ</EM></TD> +<TH ALIGN="LEFT"><B>D</B></TH> +<TD ALIGN="LEFT" NOWRAP>epoch of mean equinox to be used (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 (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>AMPRMS</EM></TD> +<TH ALIGN="LEFT"><B>D(21)</B></TH> +<TD ALIGN="LEFT" NOWRAP>star-independent mean-to-apparent parameters:</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="CENTER" NOWRAP COLSPAN=1>(1)</TD> +<TD></TD> +<TD ALIGN="LEFT" NOWRAP>time interval for proper motion (Julian years)</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="CENTER" NOWRAP COLSPAN=1>(2-4)</TD> +<TD></TD> +<TD ALIGN="LEFT" NOWRAP>barycentric position of the Earth (AU)</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="CENTER" NOWRAP COLSPAN=1>(5-7)</TD> +<TD></TD> +<TD ALIGN="LEFT" NOWRAP>heliocentric direction of the Earth (unit vector)</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="CENTER" NOWRAP COLSPAN=1>(8)</TD> +<TD></TD> +<TD ALIGN="LEFT" NOWRAP>(gravitational radius of +Sun)<IMG WIDTH="31" HEIGHT="29" ALIGN="MIDDLE" BORDER="0" + SRC="img16.gif" + ALT="$\times 2 / $">(Sun-Earth distance)</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="CENTER" NOWRAP COLSPAN=1>(9-11)</TD> +<TD></TD> +<TD ALIGN="LEFT" NOWRAP><B>v</B>: barycentric Earth velocity in units of c</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="CENTER" NOWRAP COLSPAN=1>(12)</TD> +<TD></TD> +<TD ALIGN="LEFT" NOWRAP><IMG WIDTH="72" HEIGHT="45" ALIGN="MIDDLE" BORDER="0" + SRC="img17.gif" + ALT="$\sqrt{1-\left\vert\mbox{\bf v}\right\vert^2}$"></TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="CENTER" NOWRAP COLSPAN=1>(13-21)</TD> +<TD></TD> +<TD ALIGN="LEFT" NOWRAP>precession/nutation <IMG WIDTH="39" HEIGHT="25" ALIGN="MIDDLE" BORDER="0" + SRC="img18.gif" + ALT="$3\times3$"> matrix</TD> +</TR> +</TABLE></DL> +<P> <DL> +<DT><STRONG>NOTES:</STRONG> +<DD><DL COMPACT> +<DT>1. +<DD>For DATE, the distinction between the required TDB and TT +is always negligible. Moreover, for all but the most +critical applications UTC is adequate. + <DT>2. +<DD>The accuracy of the routines using the parameters AMPRMS is + limited by the routine sla_EVP, used here to compute the + Earth position and velocity by the methods of Stumpff. + The maximum error in the resulting aberration corrections is + about 0.3 milliarcsecond. + <DT>3. +<DD>The vectors AMPRMS(2-4) and AMPRMS(5-7) are referred to + the mean equinox and equator of epoch EQ. + <DT>4. +<DD>The parameters produced by this routine are used by + sla_MAPQK and sla_MAPQKZ. + </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="tex2html1696" HREF="node128.html"> +<IMG WIDTH="37" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="next" SRC="next_motif.gif"></A> +<A NAME="tex2html1694" HREF="node13.html"> +<IMG WIDTH="26" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="up" SRC="up_motif.gif"></A> +<A NAME="tex2html1688" HREF="node126.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="tex2html1697" HREF="node128.html">SLA_MAPQK - Quick Mean to Apparent</A> +<BR> +<B>Up:</B> <A NAME="tex2html1695" HREF="node13.html">SUBPROGRAM SPECIFICATIONS</A> +<BR> +<B> Previous:</B> <A NAME="tex2html1689" HREF="node126.html">SLA_MAP - Mean to Apparent</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> |