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diff --git a/src/slalib/sun67.htx/node98.html b/src/slalib/sun67.htx/node98.html new file mode 100644 index 0000000..e5a2cc7 --- /dev/null +++ b/src/slalib/sun67.htx/node98.html @@ -0,0 +1,111 @@ +<!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_EQEQX - Equation of the Equinoxes</TITLE> +<META NAME="description" CONTENT="SLA_EQEQX - Equation of the Equinoxes"> +<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="node99.html"> +<LINK REL="previous" HREF="node97.html"> +<LINK REL="up" HREF="node13.html"> +<LINK REL="next" HREF="node99.html"> +</HEAD> +<BODY > +<BR> <HR> +<A NAME="tex2html1406" HREF="node99.html"> +<IMG WIDTH="37" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="next" SRC="next_motif.gif"></A> +<A NAME="tex2html1404" HREF="node13.html"> +<IMG WIDTH="26" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="up" SRC="up_motif.gif"></A> +<A NAME="tex2html1398" HREF="node97.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="tex2html1407" HREF="node99.html">SLA_EQGAL - J2000 to Galactic</A> +<BR> +<B>Up:</B> <A NAME="tex2html1405" HREF="node13.html">SUBPROGRAM SPECIFICATIONS</A> +<BR> +<B> Previous:</B> <A NAME="tex2html1399" HREF="node97.html">SLA_EQECL - J2000 to Ecliptic</A> +<BR> <HR> <P> +<P><!--End of Navigation Panel--> +<H2><A NAME="SECTION000485000000000000000">SLA_EQEQX - Equation of the Equinoxes</A> +<A NAME="xref_SLA_EQEQX"> </A><A NAME="SLA_EQEQX"> </A> +</H2> + <DL> +<DT><STRONG>ACTION:</STRONG> +<DD>Equation of the equinoxes (IAU 1994). +<DT><STRONG>CALL:</STRONG> +<DD><TT>D = sla_EQEQX (DATE)</TT> +<P> </DL> +<P> <DL> +<DT><STRONG>GIVEN:</STRONG> +<DD> +<BR> +<TABLE CELLPADDING=3> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM>DATE</EM></TD> +<TH ALIGN="LEFT"><B>D</B></TH> +<TD ALIGN="LEFT" NOWRAP>TDB (formerly ET) as Modified Julian Date (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>sla_EQEQX</EM></TD> +<TH ALIGN="LEFT"><B>D</B></TH> +<TD ALIGN="LEFT" NOWRAP>The equation of the equinoxes (radians)</TD> +</TR> +</TABLE></DL> +<P> <DL> +<DT><STRONG>NOTES:</STRONG> +<DD><DL COMPACT> +<DT>1. +<DD>The equation of the equinoxes is defined here as GAST - GMST: +it is added to a <I>mean</I> sidereal time to give the +<I>apparent</I> sidereal time. + <DT>2. +<DD>The change from the classic ``textbook'' expression + <IMG WIDTH="62" HEIGHT="27" ALIGN="MIDDLE" BORDER="0" + SRC="img108.gif" + ALT="$\Delta\psi\,cos\,\epsilon$"> occurred with IAU Resolution C7, + Recommendation 3 (1994). The new formulation takes into + account cross-terms between the various precession and + nutation quantities, amounting to about 3 milliarcsec. + The transition from the old to the new model officially + takes place on 1997 February 27. + </DL></DL> +<P> <DL> +<DT><STRONG>REFERENCE:</STRONG> +<DD>Capitaine, N. & Gontier, A.-M. (1993), +<I>Astron. Astrophys.</I>, + <B>275</B>, 645-650. + </DL> +<BR> <HR> +<A NAME="tex2html1406" HREF="node99.html"> +<IMG WIDTH="37" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="next" SRC="next_motif.gif"></A> +<A NAME="tex2html1404" HREF="node13.html"> +<IMG WIDTH="26" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="up" SRC="up_motif.gif"></A> +<A NAME="tex2html1398" HREF="node97.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="tex2html1407" HREF="node99.html">SLA_EQGAL - J2000 to Galactic</A> +<BR> +<B>Up:</B> <A NAME="tex2html1405" HREF="node13.html">SUBPROGRAM SPECIFICATIONS</A> +<BR> +<B> Previous:</B> <A NAME="tex2html1399" HREF="node97.html">SLA_EQECL - J2000 to Ecliptic</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> |