439 lines
15 KiB
JavaScript
439 lines
15 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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var coord = require('./coord.cjs');
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var planetposition = require('./planetposition.cjs');
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var precess = require('./precess.cjs');
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var solar = require('./solar.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 saturnmoons
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*/
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// array positions of Saturnmoons returned from positions().
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const mimas = 0;
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const enceladus = 1;
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const tethys = 2;
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const dione = 3;
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const rhea = 4;
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const titan = 5;
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const hyperion = 6;
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const iapetus = 7;
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/**
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* XYZ holds coordinates returned from positions().
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*/
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function XYZ (x, y, z) {
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this.x = x;
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this.y = y;
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this.z = z;
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}
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const d = Math.PI / 180;
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/**
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* Positions returns positions of the eight major moons of Saturn.
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*
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* Results returned in argument pos, which must not be undefined.
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*
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* Result units are Saturn radii.
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*
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* @param {number} jde - Julian ephemeris day
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* @param {Planet} earth - VSOP87 planet Earth // eslint-disable-line no-unused-vars
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* @param {Planet} saturn - VSOP87 planet Saturn // eslint-disable-line no-unused-vars
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* @return {XYZ[]} Array of Moon Positions in `XYZ`
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* Use `M.mimas ... M.iapetus` to resolve to Moon and its position at `jde`
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*/
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function positions (jde, earth, saturn) {
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const sol = solar["default"].trueVSOP87(earth, jde);
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const [s, β, R] = [sol.lon, sol.lat, sol.range];
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const [ss, cs] = base["default"].sincos(s);
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const sβ = Math.sin(β);
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let Δ = 9.0;
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let x;
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let y;
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let z = 0;
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let _jde;
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const f = function () {
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const τ = base["default"].lightTime(Δ);
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_jde = jde - τ;
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const { lon, lat, range } = saturn.position(_jde);
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const fk5 = planetposition["default"].toFK5(lon, lat, _jde); // eslint-disable-line no-unused-vars
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const [l, b] = [fk5.lon, fk5.lat];
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const [sl, cl] = base["default"].sincos(l);
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const [sb, cb] = base["default"].sincos(b);
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x = range * cb * cl + R * cs;
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y = range * cb * sl + R * ss;
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z = range * sb + R * sβ;
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Δ = Math.sqrt(x * x + y * y + z * z);
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};
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f();
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f();
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let λ0 = Math.atan2(y, x);
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let β0 = Math.atan(z / Math.hypot(x, y));
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let ecl = new coord["default"].Ecliptic(λ0, β0);
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ecl = precess["default"].eclipticPosition(ecl, base["default"].JDEToJulianYear(jde), base["default"].JDEToJulianYear(base["default"].B1950));
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λ0 = ecl.lon;
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β0 = ecl.lat;
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const q = new Qs(_jde);
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const s4 = [
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new R4(), // 0 unused
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q.mimas(),
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q.enceladus(),
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q.tethys(),
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q.dione(),
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q.rhea(),
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q.titan(),
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q.hyperion(),
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q.iapetus()
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];
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const X = new Array(9).fill(0);
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const Y = new Array(9).fill(0);
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const Z = new Array(9).fill(0);
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for (let j = 1; j <= 8; j++) {
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const u = s4[j].λ - s4[j].Ω;
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const w = s4[j].Ω - 168.8112 * d;
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const [su, cu] = base["default"].sincos(u);
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const [sw, cw] = base["default"].sincos(w);
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const [sγ, cγ] = base["default"].sincos(s4[j].γ);
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const r = s4[j].r;
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X[j] = r * (cu * cw - su * cγ * sw);
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Y[j] = r * (su * cw * cγ + cu * sw);
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Z[j] = r * su * sγ;
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}
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Z[0] = 1;
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const [sλ0, cλ0] = base["default"].sincos(λ0);
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const [sβ0, cβ0] = base["default"].sincos(β0);
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const A = new Array(9).fill(0);
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const B = new Array(9).fill(0);
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const C = new Array(9).fill(0);
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for (const j in X) {
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let a = X[j];
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let b = q.c1 * Y[j] - q.s1 * Z[j];
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const c = q.s1 * Y[j] + q.c1 * Z[j];
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const a0 = q.c2 * a - q.s2 * b;
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b = q.s2 * a + q.c2 * b;
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a = a0;
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A[j] = a * sλ0 - b * cλ0;
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b = a * cλ0 + b * sλ0;
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B[j] = b * cβ0 + c * sβ0;
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C[j] = c * cβ0 - b * sβ0;
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}
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const pos = new Array(9);
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const D = Math.atan2(A[0], C[0]);
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const [sD, cD] = base["default"].sincos(D);
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for (let j = 1; j <= 8; j++) {
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X[j] = A[j] * cD - C[j] * sD;
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Y[j] = A[j] * sD + C[j] * cD;
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Z[j] = B[j];
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const d = X[j] / s4[j].r;
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X[j] += Math.abs(Z[j]) / k[j] * Math.sqrt(1 - d * d);
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const W = Δ / (Δ + Z[j] / 2475);
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pos[j - 1] = new XYZ(X[j] * W, Y[j] * W, Z[j]);
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}
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return pos
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}
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const k = [0, 20947, 23715, 26382, 29876, 35313, 53800, 59222, 91820];
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function R4 (λ, r, γ, Ω) {
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this.λ = λ || 0;
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this.r = r || 0;
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this.γ = γ || 0;
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this.Ω = Ω || 0;
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}
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function Qs (jde) {
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this.t1 = jde - 2411093;
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this.t2 = this.t1 / 365.25;
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this.t3 = (jde - 2433282.423) / 365.25 + 1950;
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this.t4 = jde - 2411368;
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this.t5 = this.t4 / 365.25;
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this.t6 = jde - 2415020;
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this.t7 = this.t6 / 36525;
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this.t8 = this.t6 / 365.25;
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this.t9 = (jde - 2442000.5) / 365.25;
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this.t10 = jde - 2409786;
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this.t11 = this.t10 / 36525;
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this.W0 = 5.095 * d * (this.t3 - 1866.39);
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this.W1 = 74.4 * d + 32.39 * d * this.t2;
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this.W2 = 134.3 * d + 92.62 * d * this.t2;
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this.W3 = 42 * d - 0.5118 * d * this.t5;
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this.W4 = 276.59 * d + 0.5118 * d * this.t5;
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this.W5 = 267.2635 * d + 1222.1136 * d * this.t7;
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this.W6 = 175.4762 * d + 1221.5515 * d * this.t7;
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this.W7 = 2.4891 * d + 0.002435 * d * this.t7;
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this.W8 = 113.35 * d - 0.2597 * d * this.t7;
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this.s1 = Math.sin(28.0817 * d);
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this.c1 = Math.cos(28.0817 * d);
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this.s2 = Math.sin(168.8112 * d);
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this.c2 = Math.cos(168.8112 * d);
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this.e1 = 0.05589 - 0.000346 * this.t7;
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this.sW0 = Math.sin(this.W0);
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this.s3W0 = Math.sin(3 * this.W0);
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this.s5W0 = Math.sin(5 * this.W0);
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this.sW1 = Math.sin(this.W1);
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this.sW2 = Math.sin(this.W2);
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this.sW3 = Math.sin(this.W3);
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this.cW3 = Math.cos(this.W3);
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this.sW4 = Math.sin(this.W4);
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this.cW4 = Math.cos(this.W4);
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this.sW7 = Math.sin(this.W7);
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this.cW7 = Math.cos(this.W7);
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return this
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}
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Qs.prototype.mimas = function () {
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const r = new R4();
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const L = 127.64 * d + 381.994497 * d * this.t1 -
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43.57 * d * this.sW0 - 0.72 * d * this.s3W0 - 0.02144 * d * this.s5W0;
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const p = 106.1 * d + 365.549 * d * this.t2;
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const M = L - p;
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const C = 2.18287 * d * Math.sin(M) +
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0.025988 * d * Math.sin(2 * M) + 0.00043 * d * Math.sin(3 * M);
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r.λ = L + C;
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r.r = 3.06879 / (1 + 0.01905 * Math.cos(M + C));
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r.γ = 1.563 * d;
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r.Ω = 54.5 * d - 365.072 * d * this.t2;
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return r
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};
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Qs.prototype.enceladus = function () {
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const r = new R4();
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const L = 200.317 * d + 262.7319002 * d * this.t1 + 0.25667 * d * this.sW1 + 0.20883 * d * this.sW2;
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const p = 309.107 * d + 123.44121 * d * this.t2;
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const M = L - p;
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const C = 0.55577 * d * Math.sin(M) + 0.00168 * d * Math.sin(2 * M);
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r.λ = L + C;
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r.r = 3.94118 / (1 + 0.00485 * Math.cos(M + C));
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r.γ = 0.0262 * d;
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r.Ω = 348 * d - 151.95 * d * this.t2;
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return r
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};
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Qs.prototype.tethys = function () {
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const r = new R4();
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r.λ = 285.306 * d + 190.69791226 * d * this.t1 +
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2.063 * d * this.sW0 + 0.03409 * d * this.s3W0 + 0.001015 * d * this.s5W0;
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r.r = 4.880998;
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r.γ = 1.0976 * d;
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r.Ω = 111.33 * d - 72.2441 * d * this.t2;
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return r
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};
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Qs.prototype.dione = function () {
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const r = new R4();
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const L = 254.712 * d + 131.53493193 * d * this.t1 - 0.0215 * d * this.sW1 - 0.01733 * d * this.sW2;
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const p = 174.8 * d + 30.82 * d * this.t2;
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const M = L - p;
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const C = 0.24717 * d * Math.sin(M) + 0.00033 * d * Math.sin(2 * M);
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r.λ = L + C;
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r.r = 6.24871 / (1 + 0.002157 * Math.cos(M + C));
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r.γ = 0.0139 * d;
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r.Ω = 232 * d - 30.27 * d * this.t2;
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return r
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};
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Qs.prototype.rhea = function () {
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const pʹ = 342.7 * d + 10.057 * d * this.t2;
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const [spʹ, cpʹ] = base["default"].sincos(pʹ);
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const a1 = 0.000265 * spʹ + 0.001 * this.sW4;
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const a2 = 0.000265 * cpʹ + 0.001 * this.cW4;
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const e = Math.hypot(a1, a2);
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const p = Math.atan2(a1, a2);
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const N = 345 * d - 10.057 * d * this.t2;
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const [sN, cN] = base["default"].sincos(N);
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const λʹ = 359.244 * d + 79.6900472 * d * this.t1 + 0.086754 * d * sN;
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const i = 28.0362 * d + 0.346898 * d * cN + 0.0193 * d * this.cW3;
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const Ω = 168.8034 * d + 0.736936 * d * sN + 0.041 * d * this.sW3;
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const a = 8.725924;
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return this.subr(λʹ, p, e, a, Ω, i)
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};
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Qs.prototype.subr = function (λʹ, p, e, a, Ω, i) {
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const r = new R4();
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const M = λʹ - p;
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const e2 = e * e;
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const e3 = e2 * e;
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const e4 = e2 * e2;
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const e5 = e3 * e2;
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const C = (2 * e - 0.25 * e3 + 0.0520833333 * e5) * Math.sin(M) +
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(1.25 * e2 - 0.458333333 * e4) * Math.sin(2 * M) +
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(1.083333333 * e3 - 0.671875 * e5) * Math.sin(3 * M) +
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1.072917 * e4 * Math.sin(4 * M) + 1.142708 * e5 * Math.sin(5 * M);
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r.r = a * (1 - e2) / (1 + e * Math.cos(M + C)); // return value
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const g = Ω - 168.8112 * d;
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const [si, ci] = base["default"].sincos(i);
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const [sg, cg] = base["default"].sincos(g);
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const a1 = si * sg;
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const a2 = this.c1 * si * cg - this.s1 * ci;
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r.γ = Math.asin(Math.hypot(a1, a2)); // return value
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const u = Math.atan2(a1, a2);
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r.Ω = 168.8112 * d + u; // return value (w)
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const h = this.c1 * si - this.s1 * ci * cg;
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const ψ = Math.atan2(this.s1 * sg, h);
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r.λ = λʹ + C + u - g - ψ; // return value
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return r
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};
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Qs.prototype.titan = function () {
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const L = 261.1582 * d + 22.57697855 * d * this.t4 + 0.074025 * d * this.sW3;
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const iʹ = 27.45141 * d + 0.295999 * d * this.cW3;
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const Ωʹ = 168.66925 * d + 0.628808 * d * this.sW3;
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const [siʹ, ciʹ] = base["default"].sincos(iʹ);
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const [sΩʹW8, cΩʹW8] = base["default"].sincos(Ωʹ - this.W8);
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const a1 = this.sW7 * sΩʹW8;
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const a2 = this.cW7 * siʹ - this.sW7 * ciʹ * cΩʹW8;
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const g0 = 102.8623 * d;
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const ψ = Math.atan2(a1, a2);
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const s = Math.hypot(a1, a2);
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let g = this.W4 - Ωʹ - ψ;
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let ϖ = 0;
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const [s2g0, c2g0] = base["default"].sincos(2 * g0);
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const f = () => {
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ϖ = this.W4 + 0.37515 * d * (Math.sin(2 * g) - s2g0);
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g = ϖ - Ωʹ - ψ;
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};
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f();
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f();
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f();
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const eʹ = 0.029092 + 0.00019048 * (Math.cos(2 * g) - c2g0);
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const qq = 2 * (this.W5 - ϖ);
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const b1 = siʹ * sΩʹW8;
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const b2 = this.cW7 * siʹ * cΩʹW8 - this.sW7 * ciʹ;
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const θ = Math.atan2(b1, b2) + this.W8;
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const [sq, cq] = base["default"].sincos(qq);
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const e = eʹ + 0.002778797 * eʹ * cq;
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const p = ϖ + 0.159215 * d * sq;
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const u = 2 * this.W5 - 2 * θ + ψ;
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const [su, cu] = base["default"].sincos(u);
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const h = 0.9375 * eʹ * eʹ * sq + 0.1875 * s * s * Math.sin(2 * (this.W5 - θ));
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const λʹ = L - 0.254744 * d *
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(this.e1 * Math.sin(this.W6) + 0.75 * this.e1 * this.e1 * Math.sin(2 * this.W6) + h);
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const i = iʹ + 0.031843 * d * s * cu;
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const Ω = Ωʹ + 0.031843 * d * s * su / siʹ;
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const a = 20.216193;
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return this.subr(λʹ, p, e, a, Ω, i)
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};
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Qs.prototype.hyperion = function () {
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const η = 92.39 * d + 0.5621071 * d * this.t6;
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const ζ = 148.19 * d - 19.18 * d * this.t8;
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const θ = 184.8 * d - 35.41 * d * this.t9;
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const θʹ = θ - 7.5 * d;
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const as = 176 * d + 12.22 * d * this.t8;
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const bs = 8 * d + 24.44 * d * this.t8;
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const cs = bs + 5 * d;
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const ϖ = 69.898 * d - 18.67088 * d * this.t8;
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const φ = 2 * (ϖ - this.W5);
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const χ = 94.9 * d - 2.292 * d * this.t8;
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const [sη, cη] = base["default"].sincos(η);
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const [sζ, cζ] = base["default"].sincos(ζ);
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const [s2ζ, c2ζ] = base["default"].sincos(2 * ζ);
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const [s3ζ, c3ζ] = base["default"].sincos(3 * ζ);
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const [sζpη, cζpη] = base["default"].sincos(ζ + η);
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const [sζmη, cζmη] = base["default"].sincos(ζ - η);
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const [sφ, cφ] = base["default"].sincos(φ);
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const [sχ, cχ] = base["default"].sincos(χ);
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const [scs, ccs] = base["default"].sincos(cs);
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const a = 24.50601 - 0.08686 * cη - 0.00166 * cζpη + 0.00175 * cζmη;
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const e = 0.103458 - 0.004099 * cη - 0.000167 * cζpη + 0.000235 * cζmη +
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0.02303 * cζ - 0.00212 * c2ζ + 0.000151 * c3ζ + 0.00013 * cφ;
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const p = ϖ + 0.15648 * d * sχ - 0.4457 * d * sη - 0.2657 * d * sζpη - 0.3573 * d * sζmη -
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12.872 * d * sζ + 1.668 * d * s2ζ - 0.2419 * d * s3ζ - 0.07 * d * sφ;
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const λʹ = 177.047 * d + 16.91993829 * d * this.t6 + 0.15648 * d * sχ + 9.142 * d * sη +
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0.007 * d * Math.sin(2 * η) - 0.014 * d * Math.sin(3 * η) + 0.2275 * d * sζpη +
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0.2112 * d * sζmη - 0.26 * d * sζ - 0.0098 * d * s2ζ -
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0.013 * d * Math.sin(as) + 0.017 * d * Math.sin(bs) - 0.0303 * d * sφ;
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const i = 27.3347 * d + 0.6434886 * d * cχ + 0.315 * d * this.cW3 + 0.018 * d * Math.cos(θ) -
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0.018 * d * ccs;
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const Ω = 168.6812 * d + 1.40136 * d * cχ + 0.68599 * d * this.sW3 - 0.0392 * d * scs +
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0.0366 * d * Math.sin(θʹ);
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return this.subr(λʹ, p, e, a, Ω, i)
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};
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Qs.prototype.iapetus = function () {
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const L = 261.1582 * d + 22.57697855 * d * this.t4;
|
||
const ϖʹ = 91.796 * d + 0.562 * d * this.t7;
|
||
const ψ = 4.367 * d - 0.195 * d * this.t7;
|
||
const θ = 146.819 * d - 3.198 * d * this.t7;
|
||
const φ = 60.47 * d + 1.521 * d * this.t7;
|
||
const Φ = 205.055 * d - 2.091 * d * this.t7;
|
||
const eʹ = 0.028298 + 0.001156 * this.t11;
|
||
const ϖ0 = 352.91 * d + 11.71 * d * this.t11;
|
||
const μ = 76.3852 * d + 4.53795125 * d * this.t10;
|
||
const iʹ = base["default"].horner(this.t11, 18.4602 * d, -0.9518 * d, -0.072 * d, 0.0054 * d);
|
||
const Ωʹ = base["default"].horner(this.t11, 143.198 * d, -3.919 * d, 0.116 * d, 0.008 * d);
|
||
const l = μ - ϖ0;
|
||
const g = ϖ0 - Ωʹ - ψ;
|
||
const g1 = ϖ0 - Ωʹ - φ;
|
||
const ls = this.W5 - ϖʹ;
|
||
const gs = ϖʹ - θ;
|
||
const lT = L - this.W4;
|
||
const gT = this.W4 - Φ;
|
||
const u1 = 2 * (l + g - ls - gs);
|
||
const u2 = l + g1 - lT - gT;
|
||
const u3 = l + 2 * (g - ls - gs);
|
||
const u4 = lT + gT - g1;
|
||
const u5 = 2 * (ls + gs);
|
||
const [sl, cl] = base["default"].sincos(l);
|
||
const [su1, cu1] = base["default"].sincos(u1);
|
||
const [su2, cu2] = base["default"].sincos(u2);
|
||
const [su3, cu3] = base["default"].sincos(u3);
|
||
const [su4, cu4] = base["default"].sincos(u4);
|
||
const [slu2, clu2] = base["default"].sincos(l + u2);
|
||
const [sg1gT, cg1gT] = base["default"].sincos(g1 - gT);
|
||
const [su52g, cu52g] = base["default"].sincos(u5 - 2 * g);
|
||
const [su5ψ, cu5ψ] = base["default"].sincos(u5 + ψ);
|
||
const [su2φ, cu2φ] = base["default"].sincos(u2 + φ);
|
||
const [s5, c5] = base["default"].sincos(l + g1 + lT + gT + φ);
|
||
const a = 58.935028 + 0.004638 * cu1 + 0.058222 * cu2;
|
||
const e = eʹ - 0.0014097 * cg1gT + 0.0003733 * cu52g +
|
||
0.000118 * cu3 + 0.0002408 * cl + 0.0002849 * clu2 + 0.000619 * cu4;
|
||
const w = 0.08077 * d * sg1gT + 0.02139 * d * su52g - 0.00676 * d * su3 +
|
||
0.0138 * d * sl + 0.01632 * d * slu2 + 0.03547 * d * su4;
|
||
const p = ϖ0 + w / eʹ;
|
||
const λʹ = μ - 0.04299 * d * su2 - 0.00789 * d * su1 - 0.06312 * d * Math.sin(ls) -
|
||
0.00295 * d * Math.sin(2 * ls) - 0.02231 * d * Math.sin(u5) + 0.0065 * d * su5ψ;
|
||
const i = iʹ + 0.04204 * d * cu5ψ + 0.00235 * d * c5 + 0.0036 * d * cu2φ;
|
||
const wʹ = 0.04204 * d * su5ψ + 0.00235 * d * s5 + 0.00358 * d * su2φ;
|
||
const Ω = Ωʹ + wʹ / Math.sin(iʹ);
|
||
return this.subr(λʹ, p, e, a, Ω, i)
|
||
};
|
||
|
||
var saturnmoons = {
|
||
mimas,
|
||
enceladus,
|
||
tethys,
|
||
dione,
|
||
rhea,
|
||
titan,
|
||
hyperion,
|
||
iapetus,
|
||
positions,
|
||
Qs
|
||
};
|
||
|
||
exports.Qs = Qs;
|
||
exports["default"] = saturnmoons;
|
||
exports.dione = dione;
|
||
exports.enceladus = enceladus;
|
||
exports.hyperion = hyperion;
|
||
exports.iapetus = iapetus;
|
||
exports.mimas = mimas;
|
||
exports.positions = positions;
|
||
exports.rhea = rhea;
|
||
exports.tethys = tethys;
|
||
exports.titan = titan;
|