← Back to dex
Rare nebula 41 EP

Crescent Nebula

RA 303.0273° · Dec 38.3549° · openngc

Loading sky survey…
🌌 View in 3D star map
Tonight’s visibility

Computing the sky for your location…

Score breakdown

· 5 badges
41 pts · Rare
Rare 50 pts → Epic
  • Star-forming region +14
  • Nebula +8
  • Has a proper name +8
  • Bright deep-sky object +6
  • Big on the sky +5
Total score 41

9 more points to reach Epic.

Badges

  • Nebula · +8
  • Bright deep-sky object · +6
  • Has a proper name · +8
  • Star-forming region · +14
  • Big on the sky · +5

Trivia

What it actually is

  • What it actually is. An H II region: a cloud of hydrogen being ionised by the ultraviolet flood from hot young stars inside it. Every one is a star factory caught mid-production.

Find it in the sky

  • How to spot it. At magnitude 7.4 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Cygnus.
  • Northern sky. It rides the northern half of the sky — an easier target the further north you are.
  • Best time of year. It stands highest in the middle of the night around July — that's when to go looking.

Its true colour

  • Its true colour. That signature crimson is hydrogen-alpha at 656 nanometres — electrons falling back onto protons, one photon at a time.

What's in a name

  • Named. Notable enough to have earned a proper name, not just a catalogue number.

How we came to know it

  • The New General Catalogue. Its NGC number comes from J. L. E. Dreyer's 1888 catalogue, itself built on decades of sky sweeps by William Herschel and his sister Caroline.

Properties

constellation
Cyg
dso type
HII
mag
7.44
name
Crescent Nebula
named
yes
size arcmin
20

Nearby objects

About Crescent Nebula

Crescent Nebula is a rare nebula. It sits in the constellation Cyg and shines at apparent magnitude 7.44.

An H II region: a cloud of hydrogen being ionised by the ultraviolet flood from hot young stars inside it. Every one is a star factory caught mid-production.

How to see it

Look for Crescent Nebula in the constellation Cyg. At apparent magnitude 7.44, it is an easy target for binoculars.

Like any astronomical target, Crescent Nebula is best seen from a dark site away from city lights, and when it is above the horizon depends on your latitude and the time of year. The visibility panel above works out tonight's viewing window for your saved location.

Why Crescent Nebula is a rare nebula

Crescent Nebula scores 41 points on Spacedle's rarity scale, which places it in the rare tier. Another 9 points would lift it into a rarer tier.

That score comes from 5 science badges — Nebula, Bright deep-sky object, Has a proper name, Star-forming region and Big on the sky — each earned for a real, measurable property of the object. Rarity on Spacedle is never random: the more remarkable an object's astrophysics, the more badges it collects, the higher it scores, and the rarer it ranks.