DeepSkyShapeSourcetype

The place a size came from, as deepSkyShape names it: RC3 (the Third Reference Catalogue of Bright Galaxies, for a galaxy's major axis, axis ratio and angle), NED (NASA/IPAC NED's diameters table, for a galaxy RC3 does not give), or Catalogue row (the one diameter that the object's own row in the deep-sky table carries: Wikidata's, and for a Messier object what the table held already).

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

type DeepSkyShapeSource = "RC3" | "NED" | "Catalogue row";

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

const source: DeepSkyShapeSource = "RC3";
console.log(source);

RC3