About NGC 1491
NGC 1491 is an uncommon nebula. It sits in the constellation Per.
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.
Uncommon nebula 22 EP
NGC 1491
RA 60.8065° · Dec 51.3161° · openngc
Score breakdown
· 2 badgesUncommon 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
- Where to look. You'll find it in the constellation Perseus.
- 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 November — 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 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
- Per
- dso type
- HII
- name
- NGC 1491
- size arcmin
- 9
How to see it
Look for NGC 1491 in the constellation Per.
Like any astronomical target, NGC 1491 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 NGC 1491 is an uncommon nebula
NGC 1491 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.