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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 · Printable sheets: the globe and a world map to colour, my country, day and night, the seasons

terminatorfunction

The line between day and night at a moment: the points 90 degrees from where the Sun is straight overhead, as longitude and latitude.

Import it

import { terminator } from "@johnmorrisdotca/chikyu-earth/sheets";

Definition

function terminator(ms: number, points?: number): [number, number][]

Parameters

NameTypeDescription
msnumber

The moment, in milliseconds since the Unix epoch.

points (optional)number

How many points (at least 3, default 72).

Returns

[number, number][]

The points in order round the Earth.

Examples

import { terminator } from "@johnmorrisdotca/chikyu-earth/sheets";

console.log(terminator(Date.UTC(2026, 2, 20, 12), 8).length);
8

What it prints (run when this page was built)

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