From b0cb2767577a654db082f5ae9bbd69ffde725d2e Mon Sep 17 00:00:00 2001 From: "David A. Madore" Date: Tue, 27 Mar 2012 19:23:09 +0200 Subject: Equation of the origins/equinoxes. --- org/madore/ephem/Nutation.java | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) (limited to 'org/madore/ephem/Nutation.java') diff --git a/org/madore/ephem/Nutation.java b/org/madore/ephem/Nutation.java index ecc08a4..dcfdc30 100644 --- a/org/madore/ephem/Nutation.java +++ b/org/madore/ephem/Nutation.java @@ -10,7 +10,7 @@ import java.io.BufferedReader; public final class Nutation { public static enum Variable { - PSI("psi"), EPSILON("epsilon"); + PSI("psi"), EPSILON("epsilon"), EQORG("eqorg"); final String name; Variable(String name) { this.name = name; } } @@ -70,4 +70,12 @@ public final class Nutation { return mat3; } + public static double eqeqnx(double t) { // Equation of the equinoxes (=GAST-GMST, in arc seconds) + return getFunc(Variable.PSI).v(t)*Math.cos(Precession.epsilon.v(t)) + getFunc(Variable.EQORG).v(t); + } + + public static double eqorg(double t) { + return Precession.eqorg.v(t) + eqeqnx(t); + } + } -- cgit v1.2.3