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Chikyu Earth地球

A line-drawn globe of the world's countries that turns at the Earth's own rate, with an optional realistic Earth from space and markers for any place.

Chikyu is the Japanese word 地球 for the Earth. About the name

Contents

Reference · /meteors

solarLongitudefunction

The Sun's longitude along the ecliptic for the equinox of 2000.0, in degrees: the measure the shower list times its maxima by. Low precision (Meeus, Astronomical Algorithms, ch. 25, with the precession since 2000 taken off), good to about 0.01 degree from 1900 to 2100.

Import it

import { solarLongitude } from "@johnmorrisdotca/chikyu-earth/meteors";

Definition

function solarLongitude(ms: number): number

Parameters

NameTypeDescription
msnumber

The moment, in milliseconds since the epoch.

Returns

number

The longitude, 0 up to 360.

Examples

import { solarLongitude } from "@johnmorrisdotca/chikyu-earth/meteors";

// The Perseids' maximum is at 140.0 degrees.
console.log(solarLongitude(Date.UTC(2026, 7, 13, 2)).toFixed(1));
140.0

What it prints (run when this page was built)

View sourceEdit on GitHubMade from the source of @johnmorrisdotca/chikyu-earth 0.51.1.