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Hoshi Stars星

The stars you can see without a telescope, with names, colours and distances; the 88 constellations with their lines and boundaries; the Messier objects; and seven map projections to draw them on.

Hoshi is the Japanese word 星 for a star. About the name

Contents

Reference · The Messier objects

DeepSkyObjecttype

One deep-sky object. Positions are J2000 (equator and equinox of 2000), the same frame as Star.

Import it

import type { DeepSkyObject } from "@johnmorrisdotca/hoshi-stars/deep-sky";

Also exported from: @johnmorrisdotca/hoshi-stars/deep-sky/ngc-ic

Definition

interface DeepSkyObject {
    id: string;
    messier: string | undefined;
    ngc: string | undefined;
    ic: string | undefined;
    otherIds: string[];
    name: string | undefined;
    type: DeepSkyType;
    constellation: string | undefined;
    rightAscension: number;
    declination: number;
    magnitude: number | undefined;
    sizeArcmin: number | undefined;
}

Members

NameTypeDescription
idstring

The Messier designation (M31) if the object has one, else the NGC (NGC 7000), else the IC (IC 434). Unique, and a name deepSkyObject finds.

messierstring | undefined

The Messier designation (M31), or undefined.

ngcstring | undefined

The New General Catalogue designation (NGC 224), or undefined. Where an object has several (a duplicate entry, a component), the lowest plain number.

icstring | undefined

The Index Catalogue designation (IC 434), or undefined.

otherIdsstring[]

The object's other NGC and IC designations (NGC 978A, NGC 1051 for the object that is also NGC 961), each one found by deepSkyObject too. Usually empty.

namestring | undefined

The common name where Wikidata's English label is one (Andromeda Galaxy, Crab Nebula), else undefined.

type"other" | "galaxy" | "globular cluster" | "open cluster" | "nebula" | "planetary nebula" | "supernova remnant"

The kind of object.

constellationstring | undefined

The IAU three-letter constellation abbreviation (And), or undefined. It is the same text as Star.constellation.

rightAscensionnumber

Right ascension in degrees at J2000, 0 up to 360. Given to 0.0001 degree (0.36 arc-second).

declinationnumber

Declination in degrees at J2000, -90 to 90. Given to 0.0001 degree.

magnitudenumber | undefined

Visual (V band) magnitude of the whole object, or undefined where there is none (for the Messier objects there always is one). Smaller is brighter: M31 is 3.4.

sizeArcminnumber | undefined

The major axis in arc-minutes, or undefined where it is not known (most NGC and IC objects).

Examples

import { deepSkyObject, type DeepSkyObject } from "@johnmorrisdotca/hoshi-stars/deep-sky";

const andromeda: DeepSkyObject = deepSkyObject("M31")!;
console.log(andromeda.id, andromeda.ngc, andromeda.name, andromeda.magnitude);
M31 NGC 224 Andromeda Galaxy 3.4

What it prints (run when this page was built)

View sourceEdit on GitHubMade from the source of @johnmorrisdotca/hoshi-stars 0.7.0.