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diff --git a/src/slalib/sun67.htx/node188.html b/src/slalib/sun67.htx/node188.html new file mode 100644 index 0000000..bc0c8bd --- /dev/null +++ b/src/slalib/sun67.htx/node188.html @@ -0,0 +1,220 @@ +<!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_UE2PV - Pos/Vel from Universal Elements</TITLE> +<META NAME="description" CONTENT="SLA_UE2PV - Pos/Vel from Universal Elements"> +<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="node189.html"> +<LINK REL="previous" HREF="node187.html"> +<LINK REL="up" HREF="node13.html"> +<LINK REL="next" HREF="node189.html"> +</HEAD> +<BODY > +<BR> <HR> +<A NAME="tex2html2306" HREF="node189.html"> +<IMG WIDTH="37" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="next" SRC="next_motif.gif"></A> +<A NAME="tex2html2304" HREF="node13.html"> +<IMG WIDTH="26" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="up" SRC="up_motif.gif"></A> +<A NAME="tex2html2298" HREF="node187.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="tex2html2307" HREF="node189.html">SLA_UNPCD - Remove Radial Distortion</A> +<BR> +<B>Up:</B> <A NAME="tex2html2305" HREF="node13.html">SUBPROGRAM SPECIFICATIONS</A> +<BR> +<B> Previous:</B> <A NAME="tex2html2299" HREF="node187.html">SLA_UE2EL - Universal to Conventional Elements</A> +<BR> <HR> <P> +<P><!--End of Navigation Panel--> +<H2><A NAME="SECTION0004175000000000000000">SLA_UE2PV - Pos/Vel from Universal Elements</A> +<A NAME="xref_SLA_UE2PV"> </A><A NAME="SLA_UE2PV"> </A> +</H2> + <DL> +<DT><STRONG>ACTION:</STRONG> +<DD>Heliocentric position and velocity of a planet, asteroid or comet, +starting from orbital elements in the ``universal variables'' form. +<P> <DT><STRONG>CALL:</STRONG> +<DD><TT>CALL sla_UE2PV (DATE, U, PV, JSTAT)</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>date (TT Modified Julian Date = JD-2400000.5)</TD> +</TR> +</TABLE></DL> +<P> <DL> +<DT><STRONG>GIVEN and RETURNED:</STRONG> +<DD> +<BR> +<TABLE CELLPADDING=3> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM>U</EM></TD> +<TH ALIGN="LEFT"><B>D(13)</B></TH> +<TD ALIGN="LEFT" NOWRAP>universal orbital elements (updated; Note 1)</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="CENTER" NOWRAP COLSPAN=1>(1)</TD> +<TD></TD> +<TD ALIGN="LEFT" NOWRAP>combined mass (<I>M</I>+<I>m</I>)</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="CENTER" NOWRAP COLSPAN=1>(2)</TD> +<TD></TD> +<TD ALIGN="LEFT" NOWRAP>total energy of the orbit (<IMG WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0" + SRC="img24.gif" + ALT="$\alpha$">)</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="CENTER" NOWRAP COLSPAN=1>(3)</TD> +<TD></TD> +<TD ALIGN="LEFT" NOWRAP>reference (osculating) epoch (<I>t<SUB>0</SUB></I>)</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="CENTER" NOWRAP COLSPAN=1>(4-6)</TD> +<TD></TD> +<TD ALIGN="LEFT" NOWRAP>position at reference epoch (<IMG WIDTH="17" HEIGHT="25" ALIGN="MIDDLE" BORDER="0" + SRC="img102.gif" + ALT="${\rm \bf r}_0$">)</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="CENTER" NOWRAP COLSPAN=1>(7-9)</TD> +<TD></TD> +<TD ALIGN="LEFT" NOWRAP>velocity at reference epoch (<IMG WIDTH="19" HEIGHT="25" ALIGN="MIDDLE" BORDER="0" + SRC="img103.gif" + ALT="${\rm \bf v}_0$">)</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="CENTER" NOWRAP COLSPAN=1>(10)</TD> +<TD></TD> +<TD ALIGN="LEFT" NOWRAP>heliocentric distance at reference epoch</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="CENTER" NOWRAP COLSPAN=1>(11)</TD> +<TD></TD> +<TD ALIGN="LEFT" NOWRAP><IMG WIDTH="39" HEIGHT="25" ALIGN="MIDDLE" BORDER="0" + SRC="img104.gif" + ALT="${\rm \bf r}_0.{\rm \bf v}_0$"></TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="CENTER" NOWRAP COLSPAN=1>(12)</TD> +<TD></TD> +<TD ALIGN="LEFT" NOWRAP>date (<I>t</I>)</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="CENTER" NOWRAP COLSPAN=1>(13)</TD> +<TD></TD> +<TD ALIGN="LEFT" NOWRAP>universal eccentric anomaly (<IMG WIDTH="14" HEIGHT="27" ALIGN="MIDDLE" BORDER="0" + SRC="img105.gif" + ALT="$\psi$">) of date, approx</TD> +</TR> +</TABLE></DL> +<P> <DL> +<DT><STRONG>RETURNED:</STRONG> +<DD> +<BR> +<TABLE CELLPADDING=3> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM>PV</EM></TD> +<TH ALIGN="LEFT"><B>D(6)</B></TH> +<TD ALIGN="LEFT" NOWRAP>heliocentric <IMG WIDTH="106" HEIGHT="29" ALIGN="MIDDLE" BORDER="0" + SRC="img51.gif" + ALT="$[\,x,y,z,\dot{x},\dot{y},\dot{z}\,]$">, equatorial, J2000</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM></EM></TD> +<TD ALIGN="LEFT"><B></B></TD> +<TD ALIGN="LEFT" NOWRAP> (AU, AU/s; Note 1)</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM>JSTAT</EM></TD> +<TD ALIGN="LEFT"><B>I</B></TD> +<TD ALIGN="LEFT" NOWRAP>status:</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM></EM></TD> +<TD ALIGN="LEFT"><B></B></TD> +<TD ALIGN="LEFT" NOWRAP> 0 = OK</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM></EM></TD> +<TD ALIGN="LEFT"><B></B></TD> +<TD ALIGN="LEFT" NOWRAP> -1 = radius vector zero</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM></EM></TD> +<TD ALIGN="LEFT"><B></B></TD> +<TD ALIGN="LEFT" NOWRAP> -2 = failed to converge</TD> +</TR> +</TABLE></DL> +<P> <DL> +<DT><STRONG>NOTES:</STRONG> +<DD><DL COMPACT> +<DT>1. +<DD>The ``universal'' elements are those which define the orbit for the +purposes of the method of universal variables (see reference). +They consist of the combined mass of the two bodies, an epoch, + and the position and velocity vectors (arbitrary reference frame) + at that epoch. The parameter set used here includes also various + quantities that can, in fact, be derived from the other + information. This approach is taken to avoiding unnecessary + computation and loss of accuracy. The supplementary quantities + are (i) <IMG WIDTH="13" HEIGHT="14" ALIGN="BOTTOM" BORDER="0" + SRC="img24.gif" + ALT="$\alpha$">, which is proportional to the total energy of the + orbit, (ii) the heliocentric distance at epoch, + (iii) the outwards component of the velocity at the given epoch, + (iv) an estimate of <IMG WIDTH="14" HEIGHT="27" ALIGN="MIDDLE" BORDER="0" + SRC="img105.gif" + ALT="$\psi$">, the ``universal eccentric anomaly'' at a + given date and (v) that date. + <DT>2. +<DD>The companion routine is sla_EL2UE. This takes the conventional + orbital elements and transforms them into the set of numbers + needed by the present routine. A single prediction requires one + one call to sla_EL2UE followed by one call to the present routine; + for convenience, the two calls are packaged as the routine + sla_PLANEL. Multiple predictions may be made by again + calling sla_EL2UE once, but then calling the present routine + multiple times, which is faster than multiple calls to sla_PLANEL. +<P> +It is not obligatory to use sla_EL2UE to obtain the parameters. + However, it should be noted that because sla_EL2UE performs its + own validation, no checks on the contents of the array U are made + by the present routine. + <DT>3. +<DD>DATE is the instant for which the prediction is required. It is + in the TT timescale (formerly Ephemeris Time, ET) and is a + Modified Julian Date (JD-2400000.5). + <DT>4. +<DD>The universal elements supplied in the array U are in canonical + units (solar masses, AU and canonical days). The position and + velocity are not sensitive to the choice of reference frame. The + sla_EL2UE routine in fact produces coordinates with respect to the + J2000 equator and equinox. + <DT>5. +<DD>The algorithm was originally adapted from the EPHSLA program of + D.H.P.Jones (private communication, 1996). The method + is based on Stumpff's Universal Variables. + </DL></DL> +<P> <DL> +<DT><STRONG>REFERENCE:</STRONG> +<DD>Everhart, E. & Pitkin, E.T., Am. J. Phys. 51, 712, 1983. +</DL> +<BR> <HR> +<A NAME="tex2html2306" HREF="node189.html"> +<IMG WIDTH="37" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="next" SRC="next_motif.gif"></A> +<A NAME="tex2html2304" HREF="node13.html"> +<IMG WIDTH="26" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="up" SRC="up_motif.gif"></A> +<A NAME="tex2html2298" HREF="node187.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="tex2html2307" HREF="node189.html">SLA_UNPCD - Remove Radial Distortion</A> +<BR> +<B>Up:</B> <A NAME="tex2html2305" HREF="node13.html">SUBPROGRAM SPECIFICATIONS</A> +<BR> +<B> Previous:</B> <A NAME="tex2html2299" HREF="node187.html">SLA_UE2EL - Universal to Conventional Elements</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> |