95 lines
3.0 KiB
JavaScript
95 lines
3.0 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 node
|
||
*/
|
||
|
||
/**
|
||
* EllipticAscending computes time and distance of passage through the ascending node of a body in an elliptical orbit.
|
||
*
|
||
* Argument axis is semimajor axis in AU, ecc is eccentricity, argP is argument
|
||
* of perihelion in radians, timeP is time of perihelion as a jd.
|
||
*
|
||
* Result is jde of the event and distance from the sun in AU.
|
||
*/
|
||
function ellipticAscending (axis, ecc, argP, timeP) { // (axis, ecc, argP, timeP float64) (jde, r float64)
|
||
return el(-argP, axis, ecc, timeP)
|
||
}
|
||
|
||
/**
|
||
* EllipticAscending computes time and distance of passage through the descending node of a body in an elliptical orbit.
|
||
*
|
||
* Argument axis is semimajor axis in AU, ecc is eccentricity, argP is argument
|
||
* of perihelion in radians, timeP is time of perihelion as a jd.
|
||
*
|
||
* Result is jde of the event and distance from the sun in AU.
|
||
*/
|
||
function ellipticDescending (axis, ecc, argP, timeP) { // (axis, ecc, argP, timeP float64) (jde, r float64)
|
||
return el(Math.PI - argP, axis, ecc, timeP)
|
||
}
|
||
|
||
function el (ν, axis, ecc, timeP) { // (ν, axis, ecc, timeP float64) (jde, r float64)
|
||
const E = 2 * Math.atan(Math.sqrt((1 - ecc) / (1 + ecc)) * Math.tan(ν * 0.5));
|
||
const [sE, cE] = base["default"].sincos(E);
|
||
const M = E - ecc * sE;
|
||
const n = base["default"].K / axis / Math.sqrt(axis);
|
||
const jde = timeP + M / n;
|
||
const r = axis * (1 - ecc * cE);
|
||
return [jde, r]
|
||
}
|
||
|
||
/**
|
||
* ParabolicAscending computes time and distance of passage through the ascending node of a body in a parabolic orbit.
|
||
*
|
||
* Argument q is perihelion distance in AU, argP is argument of perihelion
|
||
* in radians, timeP is time of perihelion as a jd.
|
||
*
|
||
* Result is jde of the event and distance from the sun in AU.
|
||
*/
|
||
function parabolicAscending (q, argP, timeP) { // (q, argP, timeP float64) (jde, r float64)
|
||
return pa(-argP, q, timeP)
|
||
}
|
||
|
||
/**
|
||
* ParabolicDescending computes time and distance of passage through the descending node of a body in a parabolic orbit.
|
||
*
|
||
* Argument q is perihelion distance in AU, argP is argument of perihelion
|
||
* in radians, timeP is time of perihelion as a jd.
|
||
*
|
||
* Result is jde of the event and distance from the sun in AU.
|
||
*/
|
||
function parabolicDescending (q, argP, timeP) { // (q, argP, timeP float64) (jde, r float64)
|
||
return pa(Math.PI - argP, q, timeP)
|
||
}
|
||
|
||
function pa (ν, q, timeP) { // (ν, q, timeP float64) (jde, r float64)
|
||
const s = Math.tan(ν * 0.5);
|
||
const jde = timeP + 27.403895 * s * (s * s + 3) * q * Math.sqrt(q);
|
||
const r = q * (1 + s * s);
|
||
return [jde, r]
|
||
}
|
||
|
||
var node = {
|
||
ellipticAscending,
|
||
ellipticDescending,
|
||
el,
|
||
parabolicAscending,
|
||
parabolicDescending,
|
||
pa
|
||
};
|
||
|
||
exports["default"] = node;
|
||
exports.el = el;
|
||
exports.ellipticAscending = ellipticAscending;
|
||
exports.ellipticDescending = ellipticDescending;
|
||
exports.pa = pa;
|
||
exports.parabolicAscending = parabolicAscending;
|
||
exports.parabolicDescending = parabolicDescending;
|