About IC 4684
IC 4684 is an uncommon nebula. It sits in the constellation Sgr.
A reflection nebula. It produces no light at all; it is dust catching the glare of a nearby star and scattering it back at us.
Uncommon nebula 29 EP
IC 4684
RA 272.2852° · Dec -23.4354° · openngc
Score breakdown
· 4 badgesUncommon 34 pts → Rare
- Reflection nebula +10
- Nebula +8
- Toward the galactic centre +8
- On the zodiac +3
Total score 29
5 more points to reach Rare.
Badges
- Nebula · +8
- Reflection nebula · +10
- Toward the galactic centre · +8
- On the zodiac · +3
Trivia
What it actually is
- What it actually is. A reflection nebula. It produces no light at all; it is dust catching the glare of a nearby star and scattering it back at us.
Find it in the sky
- Where to look. You'll find it in the constellation Sagittarius.
- Southern sky. It rides the southern half of the sky — an easier target the further south you are.
- Best time of year. It stands highest in the middle of the night around June — that's when to go looking.
Its true colour
- Its true colour. It looks blue for exactly the reason Earth's sky is blue: fine dust scatters short blue wavelengths far more efficiently than long red ones.
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
- Sgr
- dso type
- RfN
- name
- IC 4684
- size arcmin
- 3
Nearby objects
How to see it
Look for IC 4684 in the constellation Sgr.
Like any astronomical target, IC 4684 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 4684 is an uncommon nebula
IC 4684 scores 29 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 5 points would lift it into a rarer tier.
That score comes from 4 science badges — Nebula, Reflection nebula, Toward the galactic centre and On the zodiac — 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.