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Epic nebula 53 EP

Mairan's Nebula

RA 83.8807° · Dec -5.2675° · openngc

Real photograph of Mairan's Nebula 📷 Real photo
NASA, ESA, M. Robberto (Space Telescope Science Institute/ESA) and the Hubble
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Score breakdown

· 6 badges
53 pts · Epic
Epic 78 pts → Anomaly
  • Star-forming region +14
  • Messier object +12
  • Nebula +8
  • Has a proper name +8
  • In Orion's hunting ground +6
  • Big on the sky +5
Total score 53

25 more points to reach Anomaly.

Badges

  • Nebula · +8
  • Messier object · +12
  • Has a proper name · +8
  • Star-forming region · +14
  • In Orion's hunting ground · +6
  • Big on the sky · +5

Trivia

Hard to believe

  • Messier object. One of the 110 showpieces of the Messier list — catalogued as M43.

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 9 you'll want a small backyard telescope, over in Orion.
  • Seen from everywhere. It sits almost on the celestial equator, so it can be seen from essentially anywhere on Earth.
  • Best time of year. It stands highest in the middle of the night around December — 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

  • Messier's anti-list. Charles Messier was a comet hunter, and he compiled his famous catalogue in the 1770s and 80s purely as a list of fuzzy things that are NOT comets. History remembers the distractions and forgets the comets.

Properties

constellation
Ori
dso type
HII
mag
9
messier
yes
messier number
043
name
Mairan's Nebula
named
yes
size arcmin
20

Nearby objects

About Mairan's Nebula

Mairan's Nebula is an epic nebula. It sits in the constellation Ori and shines at apparent magnitude 9.

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 Mairan's Nebula in the constellation Ori. At apparent magnitude 9, it is an easy target for binoculars.

Like any astronomical target, Mairan's 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 Mairan's Nebula is an epic nebula

Mairan's Nebula scores 53 points on Spacedle's rarity scale, which places it in the epic tier. Another 25 points would lift it into a rarer tier.

That score comes from 6 science badges — Nebula, Messier object, Has a proper name, Star-forming region, In Orion's hunting ground 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.