From d54fe7c1f704a63824c5bfa0ece65245572e9b27 Mon Sep 17 00:00:00 2001 From: Joseph Hunkeler Date: Wed, 4 Mar 2015 21:21:30 -0500 Subject: Initial commit --- src/slalib/sun67.htx/node164.html | 184 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 184 insertions(+) create mode 100644 src/slalib/sun67.htx/node164.html (limited to 'src/slalib/sun67.htx/node164.html') diff --git a/src/slalib/sun67.htx/node164.html b/src/slalib/sun67.htx/node164.html new file mode 100644 index 0000000..d45ee2f --- /dev/null +++ b/src/slalib/sun67.htx/node164.html @@ -0,0 +1,184 @@ + + + + +SLA_RDPLAN - Apparent of Planet + + + + + + + + + + + + +
+ +next + +up + +previous +
+ Next: SLA_REFCO - Refraction Constants +
+Up: SUBPROGRAM SPECIFICATIONS +
+ Previous: SLA_RCC - Barycentric Coordinate Time +

+

+

    +
+SLA_RDPLAN - Apparent $[\,\alpha,\delta\,]$ of Planet +

+
+
ACTION: +
Approximate topocentric apparent $[\,\alpha,\delta\,]$ and angular +size of a planet. +

CALL: +
CALL sla_RDPLAN (DATE, NP, ELONG, PHI, RA, DEC, DIAM) +

+

+
GIVEN: +
+
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
DATEDMJD of observation (JD-2400000.5)
NPIplanet:
1=Mercury
2=Venus
3=Moon
4=Mars
5=Jupiter
6=Saturn
7=Uranus
8=Neptune
9=Pluto
else=Sun
ELONG,PHIDobserver's longitude (east +ve) and latitude +(radians)
+

+
RETURNED: +
+
+ + + + + + + + + +
RA,DECDtopocentric apparent $[\,\alpha,\delta\,]$ (radians)
DIAMDangular diameter (equatorial, radians)
+

+
NOTES: +
+
1. +
The date is in a dynamical timescale (TDB, formerly ET) +and is in the form of a Modified +Julian Date (JD-2400000.5). For all practical purposes, TT can + be used instead of TDB, and for many applications UT will do + (except for the Moon). +
2. +
The longitude and latitude allow correction for geocentric + parallax. This is a major effect for the Moon, but in the + context of the limited accuracy of the present routine its + effect on planetary positions is small (negligible for the + outer planets). Geocentric positions can be generated by + appropriate use of the routines sla_DMOON and sla_PLANET. +
3. +
The direction accuracy (arcsec, 1000-3000AD) is of order: + 

+ 		 Sun 		   5
+		 Mercury 		   2
+		 Venus 		 10
+		 Moon 		 30
+		 Mars 		 50
+		 Jupiter 		 90
+		 Saturn 		 90
+		 Uranus 		 90
+		 Neptune 		 10
+		 Pluto 		  1   (1885-2099AD only)        
+
+ The angular diameter accuracy is about 0.4% for the Moon, + and 0.01% or better for the Sun and planets. + For more information on accuracy, + refer to the routines sla_PLANET and sla_DMOON, + which the present routine uses. +
+
+ +next + +up + +previous +
+ Next: SLA_REFCO - Refraction Constants +
+Up: SUBPROGRAM SPECIFICATIONS +
+ Previous: SLA_RCC - Barycentric Coordinate Time +

+

+

+SLALIB --- Positional Astronomy Library
Starlink User Note 67
P. T. Wallace
12 October 1999
E-mail:ptw@star.rl.ac.uk +
+ + -- cgit