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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 · Map projections for sky charts

Projectiontype

The kinds of projection.

  • stereographic: keeps shapes (conformal); the whole sphere but the antipode, stretching to the edge. Radius 2 at 90 degrees from the centre.
  • orthographic: the sky as a ball seen from far away; the near hemisphere only. Radius 1 at 90 degrees.
  • gnomonic: great circles are straight lines; less than 90 degrees from the centre.
  • equidistant: the azimuthal equidistant; distance from the centre is true, the whole sphere is a disc of radius pi.
  • equirectangular: the plain right ascension and declination plot; the centre's declination moves the chart up or down.
  • mollweide: an equal-area oval of the whole sky, turned so the centre is its middle.
  • hammer: Hammer's equal-area oval of the whole sky (often called Hammer-Aitoff), turned so the centre is its middle.

Import it

import type { Projection } from "@johnmorrisdotca/hoshi-stars/projection";

Definition

type Projection = (typeof PROJECTIONS)[number];

Examples

import { PROJECTIONS, type Projection } from "@johnmorrisdotca/hoshi-stars/projection";

const kind: Projection = PROJECTIONS[0];
console.log(kind, PROJECTIONS.length);
stereographic 7

What it prints (run when this page was built)

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