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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 faint stars: about 3 million of UCAC4's, to magnitude 12, in sky tiles loaded for the part of the sky you show

FaintTiletype

A tile, decoded: the stars of one tile as parallel arrays, sorted by declination. magnitude is in magnitudes, and colourIndex is NaN where there is none.

Import it

import type { FaintTile } from "@johnmorrisdotca/hoshi-stars/faint";

Definition

interface FaintTile {
    id: FaintTileId;
    count: number;
    rightAscension: Float64Array;
    declination: Float64Array;
    magnitude: Float64Array;
    colourIndex: Float64Array;
    parallaxMas?: Float64Array;
    properMotionRa?: Float64Array;
    properMotionDec?: Float64Array;
}

Members

NameTypeDescription
idFaintTileId
countnumber
rightAscensionFloat64Array<ArrayBufferLike>
declinationFloat64Array<ArrayBufferLike>
magnitudeFloat64Array<ArrayBufferLike>
colourIndexFloat64Array<ArrayBufferLike>
parallaxMas (optional)Float64Array<ArrayBufferLike> | undefined

Optional, from a source that has them (the package's own tiles do not): the parallax in milliarcseconds, NaN where a star has none. Types only: nothing here reads it yet.

properMotionRa (optional)Float64Array<ArrayBufferLike> | undefined

Optional: the proper motion along right ascension in milliarcseconds a year, already times cos(declination) (the usual pmRA), NaN where a star has none. Types only.

properMotionDec (optional)Float64Array<ArrayBufferLike> | undefined

Optional: the proper motion along declination in milliarcseconds a year, NaN where a star has none. Types only.

Examples

import { decodeFaintTile } from "@johnmorrisdotca/hoshi-stars/faint";

const tile = decodeFaintTile({ level: 0, band: 9, column: 0 }, new Uint8Array(0));
console.log(tile.count); // 0
0

What it prints (run when this page was built)

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