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Wakusei Planets惑星

The Sun, the planets and their moons as a clean line drawing, a shaded realistic drawing or a painted surface map, with real sizes, tilt and rotation, and the moons where they are at any date and time.

Wakusei is the Japanese word 惑星 for a planet. About the name

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Reference · Pure coordinate conversions

equatorialToHorizontalfunction

Rotate a mean equatorial-of-date direction to an observer's horizon (Meeus 12.4, 13.5–6). The input epoch must equal when. UTC approximates UT1; height is validated but unused. No parallax, refraction, nutation or horizon dip. Azimuth at zenith/nadir is conventionally zero.

Import it

import { equatorialToHorizontal } from "@johnmorrisdotca/wakusei-planets/coordinates";

Definition

function equatorialToHorizontal(value: EquatorialCoordinates, when: Date | number, options: { observer: CoordinateObserver; }): HorizontalCoordinates

Parameters

NameTypeDescription
valueEquatorialCoordinates

Mean equatorial-of-date direction with explicit origin and epoch.

whennumber | Date

Date or Unix UTC milliseconds equal to the input epoch.

options{ observer: CoordinateObserver; }

Observer in degrees north/east; height in metres above the WGS 84 ellipsoid.

Returns

HorizontalCoordinates

Altitude and north-based azimuth in degrees; original origin preserved.

Examples

import { equatorialToHorizontal } from "@johnmorrisdotca/wakusei-planets/coordinates";
console.log(equatorialToHorizontal({ origin: "topocentric", frame: "equatorialOfDate", epoch: 0, corrections: "geometric", rightAscension: 0, declination: 0 }, 0, { observer: { latitude: 49, longitude: -123 } }));
{
  origin: 'topocentric',
  frame: 'horizontal',
  epoch: 0,
  corrections: 'geometric',
  altitude: 37.223665976440316,
  azimuth: 150.91815713671042
}

What it prints (run when this page was built)

View sourceEdit on GitHubMade from the source of @johnmorrisdotca/wakusei-planets 0.24.0.