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diff --git a/src/slalib/sun67.htx/node138.html b/src/slalib/sun67.htx/node138.html new file mode 100644 index 0000000..d363298 --- /dev/null +++ b/src/slalib/sun67.htx/node138.html @@ -0,0 +1,116 @@ +<!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_PA - to Parallactic Angle</TITLE> +<META NAME="description" CONTENT="SLA_PA - to Parallactic Angle"> +<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="node139.html"> +<LINK REL="previous" HREF="node137.html"> +<LINK REL="up" HREF="node13.html"> +<LINK REL="next" HREF="node139.html"> +</HEAD> +<BODY > +<BR> <HR> +<A NAME="tex2html1806" HREF="node139.html"> +<IMG WIDTH="37" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="next" SRC="next_motif.gif"></A> +<A NAME="tex2html1804" HREF="node13.html"> +<IMG WIDTH="26" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="up" SRC="up_motif.gif"></A> +<A NAME="tex2html1798" HREF="node137.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="tex2html1807" HREF="node139.html">SLA_PAV - Position-Angle Between Two Directions</A> +<BR> +<B>Up:</B> <A NAME="tex2html1805" HREF="node13.html">SUBPROGRAM SPECIFICATIONS</A> +<BR> +<B> Previous:</B> <A NAME="tex2html1799" HREF="node137.html">SLA_OBS - Observatory Parameters</A> +<BR> <HR> <P> +<P><!--End of Navigation Panel--> +<H2><A NAME="SECTION0004125000000000000000"> </A><A NAME="xref_SLA_PA"> </A><A NAME="SLA_PA"> </A> +<BR> +SLA_PA - <IMG WIDTH="27" HEIGHT="27" ALIGN="MIDDLE" BORDER="0" + SRC="img65.gif" + ALT="$h,\delta$"> to Parallactic Angle +</H2> + <DL> +<DT><STRONG>ACTION:</STRONG> +<DD>Hour angle and declination to parallactic angle +(double precision). +<P> <DT><STRONG>CALL:</STRONG> +<DD><TT>D = sla_PA (HA, DEC, PHI)</TT> +<P> </DL> +<P> <DL> +<DT><STRONG>GIVEN:</STRONG> +<DD> +<BR> +<TABLE CELLPADDING=3> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM>HA</EM></TD> +<TH ALIGN="LEFT"><B>D</B></TH> +<TD ALIGN="LEFT" NOWRAP>hour angle in radians (geocentric apparent)</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM>DEC</EM></TD> +<TD ALIGN="LEFT"><B>D</B></TD> +<TD ALIGN="LEFT" NOWRAP>declination in radians (geocentric apparent)</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM>PHI</EM></TD> +<TD ALIGN="LEFT"><B>D</B></TD> +<TD ALIGN="LEFT" NOWRAP>latitude in radians (geodetic)</TD> +</TR> +</TABLE></DL> +<P> <DL> +<DT><STRONG>RETURNED:</STRONG> +<DD> +<BR> +<TABLE CELLPADDING=3> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM>sla_PA</EM></TD> +<TH ALIGN="LEFT"><B>D</B></TH> +<TD ALIGN="LEFT" NOWRAP>parallactic angle (radians, in the range <IMG WIDTH="25" HEIGHT="25" ALIGN="MIDDLE" BORDER="0" + SRC="img47.gif" + ALT="$\pm \pi$">)</TD> +</TR> +</TABLE></DL> +<P> <DL> +<DT><STRONG>NOTES:</STRONG> +<DD><DL COMPACT> +<DT>1. +<DD>The parallactic angle at a point in the sky is the position +angle of the vertical, <I>i.e.</I> the angle between the direction to +the pole and to the zenith. In precise applications care must + be taken only to use geocentric apparent <IMG WIDTH="41" HEIGHT="29" ALIGN="MIDDLE" BORDER="0" + SRC="img29.gif" + ALT="$[\,h,\delta\,]$"> and to consider + separately the effects of atmospheric refraction and telescope + mount errors. + <DT>2. +<DD>At the pole a zero result is returned. + </DL></DL> +<BR> <HR> +<A NAME="tex2html1806" HREF="node139.html"> +<IMG WIDTH="37" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="next" SRC="next_motif.gif"></A> +<A NAME="tex2html1804" HREF="node13.html"> +<IMG WIDTH="26" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="up" SRC="up_motif.gif"></A> +<A NAME="tex2html1798" HREF="node137.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="tex2html1807" HREF="node139.html">SLA_PAV - Position-Angle Between Two Directions</A> +<BR> +<B>Up:</B> <A NAME="tex2html1805" HREF="node13.html">SUBPROGRAM SPECIFICATIONS</A> +<BR> +<B> Previous:</B> <A NAME="tex2html1799" HREF="node137.html">SLA_OBS - Observatory Parameters</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> |