//Returns whether a has an ascending node with b. This can be false //if a is hyperbolic and the would-be ascending node is within the opening //angle of the hyperbola. public static bool AscendingNodeExists(this Orbit a, Orbit b) { return Math.Abs(MuUtils.ClampDegrees180(a.AscendingNodeTrueAnomaly(b))) <= a.MaximumTrueAnomaly(); }
//Returns the next time at which a will cross its ascending node with b. //For elliptical orbits this is a time between UT and UT + a.period. //For hyperbolic orbits this can be any time, including a time in the past if //the ascending node is in the past. //NOTE: this function will throw an ArgumentException if a is a hyperbolic orbit and the "ascending node" //occurs at a true anomaly that a does not actually ever attain public static double TimeOfAscendingNode(this Orbit a, Orbit b, double UT) { return a.TimeOfTrueAnomaly(a.AscendingNodeTrueAnomaly(b), UT); }
//Gives the true anomaly (in a's orbit) at which a crosses its descending node //with b's orbit. //The returned value is always between 0 and 360. public static double DescendingNodeTrueAnomaly(this Orbit a, Orbit b) { return MuUtils.ClampDegrees360(a.AscendingNodeTrueAnomaly(b) + 180); }