deepSkyShapefunction

The size, axis ratio and angle of a Messier, NGC or IC object on the sky. For a galaxy they are RC3's (the major axis at the 25th magnitude isophote, the axis ratio and the angle) or, where RC3 has none, NASA/IPAC NED's; for any other object, and for a galaxy with neither, the one diameter that the object's own row carries (sizeArcmin, from Wikidata, and for a Messier object what the Messier table gave), with no ratio and no angle. Every part is a measurement or undefined: no object is given an angle that a catalogue does not, and an object with no size at all has undefined. The sources are in NOTICE.md.

import { deepSkyShape } from "@johnmorrisdotca/hoshi-stars/deep-sky/ngc-ic-shape";

function deepSkyShape(object: DeepSkyObject): DeepSkyShape

import { deepSkyObject } from "@johnmorrisdotca/hoshi-stars/deep-sky/ngc-ic";
import { deepSkyShape } from "@johnmorrisdotca/hoshi-stars/deep-sky/ngc-ic-shape";

const shape = deepSkyShape(deepSkyObject("NGC 253")!);
console.log(shape.majorArcmin, shape.minorArcmin, shape.positionAngle, shape.source);

27.5 6.8 52 RC3