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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 sky out to a distance, in layers: the stars and galaxies nearer than 10, 50, 100, 500 or 1,000 light-years, each distance band its own colour, the ones with an uncertain distance kept apart, and none placed at a guess

LayeredThingtype

A thing in a layer: where it is, how far, and which band it is in.

Import it

import type { LayeredThing } from "@johnmorrisdotca/hoshi-stars/distance";

Definition

interface LayeredThing extends Omit<DistanceInput, "lightYears" | "low" | "high" | "certainty"> {
    lightYears: number;
    low: number;
    high: number;
    certainty: Certainty;
    band: number;
    uncertain: boolean;
}

Members

NameTypeDescription
lightYearsnumber

The best distance in light-years. For an uncertain thing it is the catalogue's value, not a place to draw it at.

lownumber

The nearest and the farthest it can be, in light-years.

highnumber
certaintyCertainty
bandnumber

The band of lightYears: 0 under 10 light-years, 1 under 50, 2 under 100, 3 under 500, 4 under 1,000, 5 beyond.

uncertainboolean

True when the distance is rough (certainty): the thing belongs to the uncertain band, not to band, and is drawn as a mark with no exact place, or as a streak along its line of sight from low to high.

kindLayerKind
magnitudenumber | undefined

Visual magnitude, or undefined.

namestring | undefined
rightAscensionnumber

J2000 right ascension and declination in degrees.

declinationnumber
idstring

A key that stays the same: hr-2491 for a bright star, gctp-3278 for a nearby star, M31 for a deep-sky object.

Examples

import type { LayeredThing } from "@johnmorrisdotca/hoshi-stars/distance";

const far = (thing: LayeredThing): boolean => thing.band >= 4;
console.log(typeof far);
function

What it prints (run when this page was built)

View sourceEdit on GitHubMade from the source of @johnmorrisdotca/hoshi-stars 0.47.0.