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Uncommon nebula 22 EP

IC 143

RA 23.5455° · Dec 30.7764° · openngc

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Score breakdown

· 2 badges
22 pts · Uncommon
Uncommon 34 pts → Rare
  • Star-forming region +14
  • Nebula +8
Total score 22

12 more points to reach Rare.

Badges

  • Nebula · +8
  • Star-forming region · +14

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 11.4 you'll want a small backyard telescope, over in Triangulum.
  • 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 October — 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.

How we came to know it

  • The Index Catalogue. The IC was the 1895 and 1908 supplement to the NGC — the first catalogue in history to be filled largely with objects found on photographic plates rather than by eye.

Properties

constellation
Tri
dso type
HII
mag
11.4
name
IC 143
size arcmin
0.3

Nearby objects

About IC 143

IC 143 is an uncommon nebula. It sits in the constellation Tri and shines at apparent magnitude 11.4.

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 IC 143 in the constellation Tri. At apparent magnitude 11.4, a small backyard telescope will bring it into view.

Like any astronomical target, IC 143 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 IC 143 is an uncommon nebula

IC 143 scores 22 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 12 points would lift it into a rarer tier.

That score comes from 2 science badges — Nebula and Star-forming region — 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.