ConvertFromJD2G.js

	/* Create a new date from a Julian date.
	   @param  jd  (number) the Julian date to convert
	   @return  (CDate) the equivalent date */
	fromJD: function(jd) {
		// Jean Meeus algorithm, "Astronomical Algorithms", 1991
		var z = Math.floor(jd + 0.5);
		var a = Math.floor((z - 1867216.25) / 36524.25);
		a = z + 1 + a - Math.floor(a / 4);
		var b = a + 1524;
		var c = Math.floor((b - 122.1) / 365.25);
		var d = Math.floor(365.25 * c);
		var e = Math.floor((b - d) / 30.6001);
		var day = b - d - Math.floor(e * 30.6001);
		var month = e - (e > 13.5 ? 13 : 1);
		var year = c - (month > 2.5 ? 4716 : 4715);
		if (year <= 0) { year--; } // No year zero
		return this.newDate(year, month, day);
	},