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diff --git a/src/slalib/sun67.htx/node17.html b/src/slalib/sun67.htx/node17.html new file mode 100644 index 0000000..c44bc9c --- /dev/null +++ b/src/slalib/sun67.htx/node17.html @@ -0,0 +1,205 @@ +<!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_ALTAZ - Velocities etc. for Altazimuth Mount</TITLE> +<META NAME="description" CONTENT="SLA_ALTAZ - Velocities etc. for Altazimuth Mount"> +<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="node18.html"> +<LINK REL="previous" HREF="node16.html"> +<LINK REL="up" HREF="node13.html"> +<LINK REL="next" HREF="node18.html"> +</HEAD> +<BODY > +<BR> <HR> +<A NAME="tex2html596" HREF="node18.html"> +<IMG WIDTH="37" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="next" SRC="next_motif.gif"></A> +<A NAME="tex2html594" HREF="node13.html"> +<IMG WIDTH="26" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="up" SRC="up_motif.gif"></A> +<A NAME="tex2html588" HREF="node16.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="tex2html597" HREF="node18.html">SLA_AMP - Apparent to Mean</A> +<BR> +<B>Up:</B> <A NAME="tex2html595" HREF="node13.html">SUBPROGRAM SPECIFICATIONS</A> +<BR> +<B> Previous:</B> <A NAME="tex2html589" HREF="node16.html">SLA_AIRMAS - Air Mass</A> +<BR> <HR> <P> +<P><!--End of Navigation Panel--> +<H2><A NAME="SECTION00044000000000000000">SLA_ALTAZ - Velocities <I>etc.</I> for Altazimuth Mount</A> +<A NAME="xref_SLA_ALTAZ"> </A><A NAME="SLA_ALTAZ"> </A> +</H2> + <DL> +<DT><STRONG>ACTION:</STRONG> +<DD>Positions, velocities and accelerations for an altazimuth +telescope mount tracking a star (double precision). +<P> <DT><STRONG>CALL:</STRONG> +<DD><TT>CALL sla_ALTAZ ( + HA, DEC, PHI, + AZ, AZD, AZDD, EL, ELD, ELDD, PA, PAD, PADD)</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</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM>DEC</EM></TD> +<TD ALIGN="LEFT"><B>D</B></TD> +<TD ALIGN="LEFT" NOWRAP>declination</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM>PHI</EM></TD> +<TD ALIGN="LEFT"><B>D</B></TD> +<TD ALIGN="LEFT" NOWRAP>observatory latitude</TD> +</TR> +</TABLE></DL> +<P> <DL> +<DT><STRONG>RETURNED:</STRONG> +<DD> +<BR> +<TABLE CELLPADDING=3> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM>AZ</EM></TD> +<TH ALIGN="LEFT"><B>D</B></TH> +<TD ALIGN="LEFT" NOWRAP>azimuth</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM>AZD</EM></TD> +<TD ALIGN="LEFT"><B>D</B></TD> +<TD ALIGN="LEFT" NOWRAP>azimuth velocity</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM>AZDD</EM></TD> +<TD ALIGN="LEFT"><B>D</B></TD> +<TD ALIGN="LEFT" NOWRAP>azimuth acceleration</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM>EL</EM></TD> +<TD ALIGN="LEFT"><B>D</B></TD> +<TD ALIGN="LEFT" NOWRAP>elevation</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM>ELD</EM></TD> +<TD ALIGN="LEFT"><B>D</B></TD> +<TD ALIGN="LEFT" NOWRAP>elevation velocity</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM>ELDD</EM></TD> +<TD ALIGN="LEFT"><B>D</B></TD> +<TD ALIGN="LEFT" NOWRAP>elevation acceleration</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM>PA</EM></TD> +<TD ALIGN="LEFT"><B>D</B></TD> +<TD ALIGN="LEFT" NOWRAP>parallactic angle</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM>PAD</EM></TD> +<TD ALIGN="LEFT"><B>D</B></TD> +<TD ALIGN="LEFT" NOWRAP>parallactic angle velocity</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM>PADD</EM></TD> +<TD ALIGN="LEFT"><B>D</B></TD> +<TD ALIGN="LEFT" NOWRAP>parallactic angle acceleration</TD> +</TR> +</TABLE></DL> +<P> <DL> +<DT><STRONG>NOTES:</STRONG> +<DD><DL COMPACT> +<DT>1. +<DD>Natural units are used throughout. HA, DEC, PHI, AZ, EL +and ZD are in radians. The velocities and accelerations +assume constant declination and constant rate of change of + hour angle (as for tracking a star); the units of AZD, ELD + and PAD are radians per radian of HA, while the units of AZDD, + ELDD and PADD are radians per radian of HA squared. To + convert into practical degree- and second-based units: +<P> <DIV ALIGN="CENTER"> +<TABLE CELLPADDING=3> +<TR VALIGN="TOP"><TD ALIGN="RIGHT" NOWRAP>angles</TD> +<TD ALIGN="LEFT" NOWRAP><IMG WIDTH="66" HEIGHT="29" ALIGN="MIDDLE" BORDER="0" + SRC="img9.gif" + ALT="$\times 360/2\pi$"></TD> +<TD ALIGN="CENTER" NOWRAP><IMG WIDTH="19" HEIGHT="14" ALIGN="BOTTOM" BORDER="0" + SRC="img10.gif" + ALT="$\rightarrow$"></TD> +<TD ALIGN="LEFT" NOWRAP>degrees</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="RIGHT" NOWRAP>velocities</TD> +<TD ALIGN="LEFT" NOWRAP><IMG WIDTH="178" HEIGHT="29" ALIGN="MIDDLE" BORDER="0" + SRC="img11.gif" + ALT="$\times (2\pi/86400) \times (360/2\pi)$"></TD> +<TD ALIGN="CENTER" NOWRAP><IMG WIDTH="19" HEIGHT="14" ALIGN="BOTTOM" BORDER="0" + SRC="img10.gif" + ALT="$\rightarrow$"></TD> +<TD ALIGN="LEFT" NOWRAP>degree/sec</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="RIGHT" NOWRAP>accelerations</TD> +<TD ALIGN="LEFT" NOWRAP><IMG WIDTH="186" HEIGHT="31" ALIGN="MIDDLE" BORDER="0" + SRC="img12.gif" + ALT="$\times (2\pi/86400)^2 \times (360/2\pi)$"></TD> +<TD ALIGN="CENTER" NOWRAP><IMG WIDTH="19" HEIGHT="14" ALIGN="BOTTOM" BORDER="0" + SRC="img10.gif" + ALT="$\rightarrow$"></TD> +<TD ALIGN="LEFT" NOWRAP>degree/sec/sec</TD> +</TR> +</TABLE></DIV> +<P> +Note that the seconds here are sidereal rather than SI. One + sidereal second is about 0.99727 SI seconds. +<P> +The velocity and acceleration factors assume the sidereal + tracking case. Their respective numerical values are (exactly) + 1/240 and (approximately) 1/3300236.9. + <DT>2. +<DD>Azimuth is returned in the range <IMG WIDTH="50" HEIGHT="29" ALIGN="MIDDLE" BORDER="0" + SRC="img13.gif" + ALT="$[\,0,2\pi\,]$">; north is zero, + and east is <IMG WIDTH="41" HEIGHT="29" ALIGN="MIDDLE" BORDER="0" + SRC="img14.gif" + ALT="$+\pi/2$">. Elevation and parallactic angle are + returned in the range <IMG WIDTH="41" HEIGHT="29" ALIGN="MIDDLE" BORDER="0" + SRC="img15.gif" + ALT="$\pm\pi/2$">. Position angle is +ve + for a star west of the meridian and is the angle NP-star-zenith. + <DT>3. +<DD>The latitude is geodetic as opposed to geocentric. The + hour angle and declination are topocentric. Refraction and + deficiencies in the telescope mounting are ignored. The + purpose of the routine is to give the general form of the + quantities. The details of a real telescope could profoundly + change the results, especially close to the zenith. + <DT>4. +<DD>No range checking of arguments is carried out. + <DT>5. +<DD>In applications which involve many such calculations, rather + than calling the present routine it will be more efficient to + use inline code, having previously computed fixed terms such + as sine and cosine of latitude, and (for tracking a star) + sine and cosine of declination. + </DL></DL> +<BR> <HR> +<A NAME="tex2html596" HREF="node18.html"> +<IMG WIDTH="37" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="next" SRC="next_motif.gif"></A> +<A NAME="tex2html594" HREF="node13.html"> +<IMG WIDTH="26" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="up" SRC="up_motif.gif"></A> +<A NAME="tex2html588" HREF="node16.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="tex2html597" HREF="node18.html">SLA_AMP - Apparent to Mean</A> +<BR> +<B>Up:</B> <A NAME="tex2html595" HREF="node13.html">SUBPROGRAM SPECIFICATIONS</A> +<BR> +<B> Previous:</B> <A NAME="tex2html589" HREF="node16.html">SLA_AIRMAS - Air Mass</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> |