@observerly/astrometry/dist/coordinates.js

observerly's lightweight, zero-dependency, type safe astrometry library written in Typescript for calculating the position of celestial objects in the sky.

import { getObliquityOfTheEcliptic as d, getHourAngle as m, getLocalSiderealTime as T } from "./astrometry.js";
import { c as t, e as M } from "./utilities-BM-rBPno.js";
// @license        Copyright © 2021-2023 observerly
const v = (e, i) => {
  const o = t(d(e)), a = t(i.λ), c = t(i.β), s = Math.atan2(Math.sin(a) * Math.cos(o) - Math.tan(c) * Math.sin(o), Math.cos(a)), n = Math.asin(Math.sin(c) * Math.cos(o) + Math.cos(c) * Math.sin(o) * Math.sin(a));
  return {
    ra: M(s) < 0 ? M(s) + 360 : M(s),
    dec: M(n)
  };
}, E = (e) => {
  let { ra: i, dec: o } = { ra: 0, dec: 0 };
  const a = t(192.8598), c = t(27.128027), s = t(32.9319), n = t(e.b), h = t(e.l);
  o = M(Math.asin(Math.cos(n) * Math.cos(c) * Math.sin(h - s) + Math.sin(n) * Math.sin(c)));
  const r = Math.cos(n) * Math.cos(h - s), u = Math.sin(n) * Math.cos(c) - Math.cos(n) * Math.sin(c) * Math.sin(h - s);
  return i = M(Math.atan2(r, u) + a) % 360, i < 0 && (i += 360), {
    ra: i,
    dec: o
  };
}, p = (e, i, o) => {
  const { latitude: a, longitude: c } = i, s = t(o.dec);
  if (Math.cos(t(a)) === 0)
    return {
      alt: -1,
      az: -1
    };
  const n = t(m(e, c, o.ra)), h = Math.asin(Math.max(-1, Math.min(1, Math.sin(s) * Math.sin(t(a)) + Math.cos(s) * Math.cos(t(a)) * Math.cos(n)))), r = Math.acos(Math.max(-1, Math.min(1, (Math.sin(s) - Math.sin(t(a)) * Math.sin(h)) / (Math.cos(t(a)) * Math.cos(h)))));
  return {
    alt: M(h),
    az: Math.sin(n) > 0 ? 360 - M(r) : M(r)
  };
}, q = (e, i, o) => {
  const { latitude: a, longitude: c } = i, s = t(o.alt), n = t(o.az), h = Math.asin(Math.sin(t(a)) * Math.sin(s) + Math.cos(t(a)) * Math.cos(s) * Math.cos(n));
  let r = Math.atan2(-Math.sin(n) * Math.cos(s) / Math.cos(h), (Math.sin(s) - Math.sin(t(a)) * Math.sin(h)) / (Math.cos(t(a)) * Math.cos(h)));
  r < 0 && (r += 2 * Math.PI);
  let l = T(e, c) * 15 - M(r);
  return l < 0 && (l += 360), {
    ra: l % 360,
    dec: M(h)
  };
};
export {
  v as convertEclipticToEquatorial,
  p as convertEquatorialToHorizontal,
  E as convertGalacticToEquatorial,
  q as convertHorizontalToEquatorial
};
//# sourceMappingURL=coordinates.js.map