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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

Contents

Reference · Julian dates (and the julian package's functions), calendars, time scales, sidereal time and Mars time

localSiderealTimefunction

The local sidereal time in degrees, 0 to 360, at a longitude east of Greenwich (west negative): the right ascension on the meridian.

Import it

import { localSiderealTime } from "@johnmorrisdotca/wakusei-planets/time";

Definition

function localSiderealTime(when: When, longitude: number, options?: { apparent?: boolean; dut1?: number; }): number

Parameters

NameTypeDescription
whenWhen

A Date or milliseconds since 1970 (UTC).

longitudenumber

Degrees east.

options (optional){ apparent?: boolean; dut1?: number; }

apparent (default true: with the equation of the equinoxes) and dut1, UT1 minus UTC in seconds.

Returns

number

Degrees.

Examples

import { localSiderealTime } from "@johnmorrisdotca/wakusei-planets/time";

console.log(localSiderealTime(Date.UTC(2026, 10, 7, 12), -123.1).toFixed(2));
103.61

What it prints (run when this page was built)

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