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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

MeteorShowertype

One meteor shower of the working list.

Import it

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

Definition

interface MeteorShower {
    code: string;
    iau: number;
    name: string;
    nameJa: string;
    start: readonly [
        month: number,
        day: number
    ];
    end: readonly [
        month: number,
        day: number
    ];
    peak: readonly [
        month: number,
        day: number
    ];
    peakSolarLongitude: number;
    radiant: {
        ra: number;
        dec: number;
    };
    speedKmS: number;
    populationIndex: number;
    zhr: number | null;
    parent?: string;
}

Members

NameTypeDescription
codestring

The IAU's three-letter code: PER for the Perseids.

iaunumber

The IAU's number for the shower.

namestring
nameJastring

The name used in Japan.

startreadonly [month: number, day: number]

The first day of activity, as month (1 to 12) and day. A shower may run over the new year.

endreadonly [month: number, day: number]

The last day of activity.

peakreadonly [month: number, day: number]

The day of the maximum in 2026; in other years it can fall a day either side. peakSolarLongitude is the lasting figure.

peakSolarLongitudenumber

The Sun's longitude at the maximum, in degrees, for the equinox of 2000.0: where the Earth is on its orbit, whatever the calendar says.

radiant{ ra: number; dec: number; }

The radiant at the maximum: right ascension and declination, in degrees.

speedKmSnumber

The speed the meteors meet the atmosphere at, in kilometres a second: 11 is very slow, 72 very fast.

populationIndexnumber

The population index r: 2.0 to 2.5 has more bright meteors than average, above 3.0 more faint ones.

zhrnumber | null

The zenithal hourly rate at the maximum: what an ideal watcher would count in an hour under a perfect sky with the radiant overhead. null where the list says the rate varies from year to year.

parent (optional)string | undefined

The comet or asteroid whose dust it is, where a source used here names one.

Examples

import { METEOR_SHOWERS, type MeteorShower } from "@johnmorrisdotca/chikyu-earth/meteors";

const perseids: MeteorShower | undefined = METEOR_SHOWERS.find((shower) => shower.code === "PER");
console.log(perseids?.name, perseids?.zhr, perseids?.parent);
Perseids 100 comet 109P/Swift-Tuttle

What it prints (run when this page was built)

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