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/node154.html | 131 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 131 insertions(+) create mode 100644 src/slalib/sun67.htx/node154.html (limited to 'src/slalib/sun67.htx/node154.html') diff --git a/src/slalib/sun67.htx/node154.html b/src/slalib/sun67.htx/node154.html new file mode 100644 index 0000000..a20e26a --- /dev/null +++ b/src/slalib/sun67.htx/node154.html @@ -0,0 +1,131 @@ + + + + +SLA_PRECL - Precession Matrix (latest) + + + + + + + + + + + + +
+ +next + +up + +previous +
+ Next: SLA_PRENUT - Precession/Nutation Matrix +
+Up: SUBPROGRAM SPECIFICATIONS +
+ Previous: SLA_PRECES - Precession +

+

+

SLA_PRECL - Precession Matrix (latest) +   +

+
+
ACTION: +
Form the matrix of precession between two epochs, using the +model of Simon et al. (1994), which is suitable for long + periods of time. +

CALL: +
CALL sla_PRECL (EP0, EP1, RMATP) +

+

+
GIVEN: +
+
+ + + + + + + + + +
EP0Dbeginning epoch
EP1Dending epoch
+

+
RETURNED: +
+
+ + + + + +
RMATPD(3,3)precession matrix
+

+
NOTES: +
+
1. +
The epochs are TDB Julian epochs. +
2. +
The matrix is in the sense: +
v1 = M$\cdot$v0
+ where v1 is the star vector relative to the + mean equator and equinox of epoch EP1, M is the + $3\times3$ matrix RMATP and + v0 is the star vector relative to the + mean equator and equinox of epoch EP0. +
3. +
The absolute accuracy of the model is limited by the + uncertainty in the general precession, about + $0\hspace{-0.05em}^{'\hspace{-0.1em}'}\hspace{-0.4em}.3$ per + 1000 years. The remainder of the formulation provides a + precision of 1 milliarcsecond over the interval from 1000AD + to 3000AD, + $0\hspace{-0.05em}^{'\hspace{-0.1em}'}\hspace{-0.4em}.1$ from 1000BC to 5000AD and + $1\hspace{-0.05em}^{'\hspace{-0.1em}'}$ from 4000BC to 8000AD. +
+

+
REFERENCE: +
Simon, J.L. et al., 1994. Astr.Astrophys. 282, +663. +
+
+ +next + +up + +previous +
+ Next: SLA_PRENUT - Precession/Nutation Matrix +
+Up: SUBPROGRAM SPECIFICATIONS +
+ Previous: SLA_PRECES - Precession +

+

+

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