338 lines
9.8 KiB
JavaScript
338 lines
9.8 KiB
JavaScript
'use strict';
|
|
|
|
Object.defineProperty(exports, '__esModule', { value: true });
|
|
|
|
var base = require('./base.cjs');
|
|
|
|
/**
|
|
* @copyright 2013 Sonia Keys
|
|
* @copyright 2016 commenthol
|
|
* @license MIT
|
|
* @module apsis
|
|
*/
|
|
const { sin, cos } = Math;
|
|
|
|
/**
|
|
* conversion factor from k to T, given in (50.3) p. 356
|
|
*/
|
|
const ck = 1 / 1325.55;
|
|
const D2R = Math.PI / 180;
|
|
|
|
// from http://nssdc.gsfc.nasa.gov/planetary/factsheet/earthfact.html
|
|
const EARTH_RADIUS = 6378.137; // km
|
|
// from http://nssdc.gsfc.nasa.gov/planetary/factsheet/moonfact.html
|
|
const MOON_RADIUS = 1738.1; // km
|
|
|
|
/**
|
|
* mean time of perigee or apogee
|
|
* (50.1) p. 355
|
|
*/
|
|
const mean = function (T) {
|
|
return base["default"].horner(T, 2451534.6698, 27.55454989 / ck,
|
|
-0.0006691, -0.000001098, 0.0000000052)
|
|
};
|
|
|
|
/**
|
|
* snap returns k at half h nearest year y.
|
|
*/
|
|
const snap = function (y, h) {
|
|
const k = (y - 1999.97) * 13.2555; // (50.2) p. 355
|
|
return Math.floor(k - h + 0.5) + h
|
|
};
|
|
|
|
/**
|
|
* meanPerigee returns the jde of the mean perigee of the Moon nearest the given date.
|
|
*
|
|
* @param {Number} year - is a decimal year specifying a date.
|
|
* @return {Number} jde - Julian ephemeris day
|
|
*/
|
|
function meanPerigee (year) {
|
|
return mean(snap(year, 0) * ck)
|
|
}
|
|
|
|
/**
|
|
* perigee returns the jde of perigee of the Moon nearest the given date.
|
|
*
|
|
* @param {Number} year - is a decimal year specifying a date.
|
|
* @return {Number} jde - Julian ephemeris day
|
|
*/
|
|
function perigee (year) {
|
|
const l = new La(year, 0);
|
|
return mean(l.T) + l.perigeeCorr()
|
|
}
|
|
|
|
/**
|
|
* meanApogee returns the jde of the mean apogee of the Moon nearest the given date.
|
|
*
|
|
* @param {Number} year - is a decimal year specifying a date.
|
|
* @return {Number} jde - Julian ephemeris day
|
|
*/
|
|
function meanApogee (year) { // (year float64) float64
|
|
return mean(snap(year, 0.5) * ck)
|
|
}
|
|
|
|
/**
|
|
* apogee returns the jde of apogee of the Moon nearest the given date.
|
|
*
|
|
* @param {Number} year - is a decimal year specifying a date.
|
|
* @return {Number} jde - Julian ephemeris day
|
|
*/
|
|
function apogee (year) {
|
|
const l = new La(year, 0.5);
|
|
return mean(l.T) + l.apogeeCorr()
|
|
}
|
|
|
|
/**
|
|
* apogeeParallax returns equatorial horizontal parallax of the Moon at the Apogee nearest the given date.
|
|
*
|
|
* @param {Number} year - is a decimal year specifying a date.
|
|
* @return {Number} equatorial horizontal parallax in radians
|
|
*/
|
|
function apogeeParallax (year) {
|
|
return new La(year, 0.5).apogeeParallax()
|
|
}
|
|
|
|
/**
|
|
* perigeeParallax returns equatorial horizontal parallax of the Moon at the Apogee nearest the given date.
|
|
*
|
|
* @param {Number} year - is a decimal year specifying a date.
|
|
* @return {Number} equatorial horizontal parallax in radians
|
|
*/
|
|
function perigeeParallax (year) {
|
|
return new La(year, 0).perigeeParallax()
|
|
}
|
|
|
|
/**
|
|
* Calculate the distance earth - moon (center to center) using the parallax angle in radians
|
|
*
|
|
* @param {Number} parallax - parallax angle in radians
|
|
* @return {Number} distance in `km`
|
|
*/
|
|
function distance (parallax) {
|
|
return EARTH_RADIUS / sin(parallax)
|
|
}
|
|
|
|
class La {
|
|
constructor (y, h) {
|
|
this.k = snap(y, h);
|
|
this.T = this.k * ck; // (50.3) p. 350
|
|
this.D = base["default"].horner(this.T, 171.9179 * D2R, 335.9106046 * D2R / ck,
|
|
-0.0100383 * D2R, -0.00001156 * D2R, 0.000000055 * D2R);
|
|
this.M = base["default"].horner(this.T, 347.3477 * D2R, 27.1577721 * D2R / ck,
|
|
-0.000813 * D2R, -0.000001 * D2R);
|
|
this.F = base["default"].horner(this.T, 316.6109 * D2R, 364.5287911 * D2R / ck,
|
|
-0.0125053 * D2R, -0.0000148 * D2R);
|
|
return this
|
|
}
|
|
|
|
/**
|
|
* perigee correction
|
|
*/
|
|
perigeeCorr () {
|
|
const l = this;
|
|
return -1.6769 * sin(2 * l.D) +
|
|
0.4589 * sin(4 * l.D) +
|
|
-0.1856 * sin(6 * l.D) +
|
|
0.0883 * sin(8 * l.D) +
|
|
(-0.0773 + 0.00019 * l.T) * sin(2 * l.D - l.M) +
|
|
(0.0502 - 0.00013 * l.T) * sin(l.M) +
|
|
-0.046 * sin(10 * l.D) +
|
|
(0.0422 - 0.00011 * l.T) * sin(4 * l.D - l.M) +
|
|
-0.0256 * sin(6 * l.D - l.M) +
|
|
0.0253 * sin(12 * l.D) +
|
|
0.0237 * sin(l.D) +
|
|
0.0162 * sin(8 * l.D - l.M) +
|
|
-0.0145 * sin(14 * l.D) +
|
|
0.0129 * sin(2 * l.F) +
|
|
-0.0112 * sin(3 * l.D) +
|
|
-0.0104 * sin(10 * l.D - l.M) +
|
|
0.0086 * sin(16 * l.D) +
|
|
0.0069 * sin(12 * l.D - l.M) +
|
|
0.0066 * sin(5 * l.D) +
|
|
-0.0053 * sin(2 * (l.D + l.F)) +
|
|
-0.0052 * sin(18 * l.D) +
|
|
-0.0046 * sin(14 * l.D - l.M) +
|
|
-0.0041 * sin(7 * l.D) +
|
|
0.004 * sin(2 * l.D + l.M) +
|
|
0.0032 * sin(20 * l.D) +
|
|
-0.0032 * sin(l.D + l.M) +
|
|
0.0031 * sin(16 * l.D - l.M) +
|
|
-0.0029 * sin(4 * l.D + l.M) +
|
|
0.0027 * sin(9 * l.D) +
|
|
0.0027 * sin(4 * l.D + 2 * l.F) +
|
|
-0.0027 * sin(2 * (l.D - l.M)) +
|
|
0.0024 * sin(4 * l.D - 2 * l.M) +
|
|
-0.0021 * sin(6 * l.D - 2 * l.M) +
|
|
-0.0021 * sin(22 * l.D) +
|
|
-0.0021 * sin(18 * l.D - l.M) +
|
|
0.0019 * sin(6 * l.D + l.M) +
|
|
-0.0018 * sin(11 * l.D) +
|
|
-0.0014 * sin(8 * l.D + l.M) +
|
|
-0.0014 * sin(4 * l.D - 2 * l.F) +
|
|
-0.0014 * sin(6 * l.D + 2 * l.F) +
|
|
0.0014 * sin(3 * l.D + l.M) +
|
|
-0.0014 * sin(5 * l.D + l.M) +
|
|
0.0013 * sin(13 * l.D) +
|
|
0.0013 * sin(20 * l.D - l.M) +
|
|
0.0011 * sin(3 * l.D + 2 * l.M) +
|
|
-0.0011 * sin(2 * (2 * l.D + l.F - l.M)) +
|
|
-0.001 * sin(l.D + 2 * l.M) +
|
|
-0.0009 * sin(22 * l.D - l.M) +
|
|
-0.0008 * sin(4 * l.F) +
|
|
0.0008 * sin(6 * l.D - 2 * l.F) +
|
|
0.0008 * sin(2 * (l.D - l.F) + l.M) +
|
|
0.0007 * sin(2 * l.M) +
|
|
0.0007 * sin(2 * l.F - l.M) +
|
|
0.0007 * sin(2 * l.D + 4 * l.F) +
|
|
-0.0006 * sin(2 * (l.F - l.M)) +
|
|
-0.0006 * sin(2 * (l.D - l.F + l.M)) +
|
|
0.0006 * sin(24 * l.D) +
|
|
0.0005 * sin(4 * (l.D - l.F)) +
|
|
0.0005 * sin(2 * (l.D + l.M)) +
|
|
-0.0004 * sin(l.D - l.M)
|
|
}
|
|
|
|
/**
|
|
* apogee correction
|
|
*/
|
|
apogeeCorr () {
|
|
const l = this;
|
|
return 0.4392 * sin(2 * l.D) +
|
|
0.0684 * sin(4 * l.D) +
|
|
(0.0456 - 0.00011 * l.T) * sin(l.M) +
|
|
(0.0426 - 0.00011 * l.T) * sin(2 * l.D - l.M) +
|
|
0.0212 * sin(2 * l.F) +
|
|
-0.0189 * sin(l.D) +
|
|
0.0144 * sin(6 * l.D) +
|
|
0.0113 * sin(4 * l.D - l.M) +
|
|
0.0047 * sin(2 * (l.D + l.F)) +
|
|
0.0036 * sin(l.D + l.M) +
|
|
0.0035 * sin(8 * l.D) +
|
|
0.0034 * sin(6 * l.D - l.M) +
|
|
-0.0034 * sin(2 * (l.D - l.F)) +
|
|
0.0022 * sin(2 * (l.D - l.M)) +
|
|
-0.0017 * sin(3 * l.D) +
|
|
0.0013 * sin(4 * l.D + 2 * l.F) +
|
|
0.0011 * sin(8 * l.D - l.M) +
|
|
0.001 * sin(4 * l.D - 2 * l.M) +
|
|
0.0009 * sin(10 * l.D) +
|
|
0.0007 * sin(3 * l.D + l.M) +
|
|
0.0006 * sin(2 * l.M) +
|
|
0.0005 * sin(2 * l.D + l.M) +
|
|
0.0005 * sin(2 * (l.D + l.M)) +
|
|
0.0004 * sin(6 * l.D + 2 * l.F) +
|
|
0.0004 * sin(6 * l.D - 2 * l.M) +
|
|
0.0004 * sin(10 * l.D - l.M) +
|
|
-0.0004 * sin(5 * l.D) +
|
|
-0.0004 * sin(4 * l.D - 2 * l.F) +
|
|
0.0003 * sin(2 * l.F + l.M) +
|
|
0.0003 * sin(12 * l.D) +
|
|
0.0003 * sin(2 * l.D + 2 * l.F - l.M) +
|
|
-0.0003 * sin(l.D - l.M)
|
|
}
|
|
|
|
/**
|
|
* apogee parallax
|
|
*/
|
|
apogeeParallax () {
|
|
const s = Math.PI / 180 / 3600;
|
|
const l = this;
|
|
return 3245.251 * s +
|
|
-9.147 * s * cos(2 * l.D) +
|
|
-0.841 * s * cos(l.D) +
|
|
0.697 * s * cos(2 * l.F) +
|
|
(-0.656 * s + 0.0016 * s * l.T) * cos(l.M) +
|
|
0.355 * s * cos(4 * l.D) +
|
|
0.159 * s * cos(2 * l.D - l.M) +
|
|
0.127 * s * cos(l.D + l.M) +
|
|
0.065 * s * cos(4 * l.D - l.M) +
|
|
0.052 * s * cos(6 * l.D) +
|
|
0.043 * s * cos(2 * l.D + l.M) +
|
|
0.031 * s * cos(2 * (l.D + l.F)) +
|
|
-0.023 * s * cos(2 * (l.D - l.F)) +
|
|
0.022 * s * cos(2 * (l.D - l.M)) +
|
|
0.019 * s * cos(2 * (l.D + l.M)) +
|
|
-0.016 * s * cos(2 * l.M) +
|
|
0.014 * s * cos(6 * l.D - l.M) +
|
|
0.01 * s * cos(8 * l.D)
|
|
}
|
|
|
|
/**
|
|
* perigee parallax
|
|
*/
|
|
perigeeParallax () {
|
|
const s = Math.PI / 180 / 3600;
|
|
const l = this;
|
|
return 3629.215 * s +
|
|
63.224 * s * cos(2 * l.D) +
|
|
-6.990 * s * cos(4 * l.D) +
|
|
(2.834 * s - 0.0071 * l.T * s) * cos(2 * l.D - l.M) +
|
|
1.927 * s * cos(6 * l.D) +
|
|
-1.263 * s * cos(l.D) +
|
|
-0.702 * s * cos(8 * l.D) +
|
|
(0.696 * s - 0.0017 * l.T * s) * cos(l.M) +
|
|
-0.690 * s * cos(2 * l.F) +
|
|
(-0.629 * s + 0.0016 * l.T * s) * cos(4 * l.D - l.M) +
|
|
-0.392 * s * cos(2 * (l.D - l.F)) +
|
|
0.297 * s * cos(10 * l.D) +
|
|
0.260 * s * cos(6 * l.D - l.M) +
|
|
0.201 * s * cos(3 * l.D) +
|
|
-0.161 * s * cos(2 * l.D + l.M) +
|
|
0.157 * s * cos(l.D + l.M) +
|
|
-0.138 * s * cos(12 * l.D) +
|
|
-0.127 * s * cos(8 * l.D - l.M) +
|
|
0.104 * s * cos(2 * (l.D + l.F)) +
|
|
0.104 * s * cos(2 * (l.D - l.M)) +
|
|
-0.079 * s * cos(5 * l.D) +
|
|
0.068 * s * cos(14 * l.D) +
|
|
0.067 * s * cos(10 * l.D - l.M) +
|
|
0.054 * s * cos(4 * l.D + l.M) +
|
|
-0.038 * s * cos(12 * l.D - l.M) +
|
|
-0.038 * s * cos(4 * l.D - 2 * l.M) +
|
|
0.037 * s * cos(7 * l.D) +
|
|
-0.037 * s * cos(4 * l.D + 2 * l.F) +
|
|
-0.035 * s * cos(16 * l.D) +
|
|
-0.030 * s * cos(3 * l.D + l.M) +
|
|
0.029 * s * cos(l.D - l.M) +
|
|
-0.025 * s * cos(6 * l.D + l.M) +
|
|
0.023 * s * cos(2 * l.M) +
|
|
0.023 * s * cos(14 * l.D - l.M) +
|
|
-0.023 * s * cos(2 * (l.D + l.M)) +
|
|
0.022 * s * cos(6 * l.D - 2 * l.M) +
|
|
-0.021 * s * cos(2 * l.D - 2 * l.F - l.M) +
|
|
-0.020 * s * cos(9 * l.D) +
|
|
0.019 * s * cos(18 * l.D) +
|
|
0.017 * s * cos(6 * l.D + 2 * l.F) +
|
|
0.014 * s * cos(2 * l.F - l.M) +
|
|
-0.014 * s * cos(16 * l.D - l.M) +
|
|
0.013 * s * cos(4 * l.D - 2 * l.F) +
|
|
0.012 * s * cos(8 * l.D + l.M) +
|
|
0.011 * s * cos(11 * l.D) +
|
|
0.010 * s * cos(5 * l.D + l.M) +
|
|
-0.010 * s * cos(20 * l.D)
|
|
}
|
|
}
|
|
|
|
var apsis = {
|
|
EARTH_RADIUS,
|
|
MOON_RADIUS,
|
|
meanPerigee,
|
|
perigee,
|
|
meanApogee,
|
|
apogee,
|
|
apogeeParallax,
|
|
perigeeParallax,
|
|
distance
|
|
};
|
|
|
|
exports.EARTH_RADIUS = EARTH_RADIUS;
|
|
exports.MOON_RADIUS = MOON_RADIUS;
|
|
exports.apogee = apogee;
|
|
exports.apogeeParallax = apogeeParallax;
|
|
exports["default"] = apsis;
|
|
exports.distance = distance;
|
|
exports.meanApogee = meanApogee;
|
|
exports.meanPerigee = meanPerigee;
|
|
exports.perigee = perigee;
|
|
exports.perigeeParallax = perigeeParallax;
|