55 lines
1.2 KiB
JavaScript
55 lines
1.2 KiB
JavaScript
'use strict';
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Object.defineProperty(exports, '__esModule', { value: true });
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var base = require('./base.cjs');
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/**
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* @copyright 2013 Sonia Keys
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* @copyright 2016 commenthol
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* @license MIT
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* @module parabolic
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*/
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/**
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* Elements holds parabolic elements needed for computing true anomaly and distance.
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*/
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class Elements {
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/**
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* @param {Number} timeP - time of perihelion, T
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* @param {Number} pDis - perihelion distance, q
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*/
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constructor (timeP, pDis) {
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this.timeP = timeP;
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this.pDis = pDis;
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}
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/**
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* AnomalyDistance returns true anomaly and distance of a body in a parabolic orbit of the Sun.
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*
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* @param {Number} jde - Julian ephemeris day
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* @returns {Object} {ano, dist}
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* {Number} ano - True anomaly ν in radians.
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* {Number} dist - Distance r returned in AU.
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*/
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anomalyDistance (jde) {
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const W = 3 * base["default"].K / Math.SQRT2 * (jde - this.timeP) / this.pDis / Math.sqrt(this.pDis);
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const G = W * 0.5;
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const Y = Math.cbrt(G + Math.sqrt(G * G + 1));
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const s = Y - 1 / Y;
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const ν = 2 * Math.atan(s);
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const r = this.pDis * (1 + s * s);
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return {
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ano: ν,
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dist: r
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}
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}
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}
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var parabolic = {
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Elements
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};
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exports.Elements = Elements;
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exports["default"] = parabolic;
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