Horsehead Nebula
E132579
The Horsehead Nebula is a dark molecular cloud in the constellation Orion, famous for its distinctive horse-head shape silhouetted against a bright emission nebula.
All labels observed (4)
| Label | Occurrences |
|---|---|
| Horsehead Nebula canonical | 13 |
| Horsehead Nebula region | 5 |
| Horsehead Nebula (Barnard 33) | 2 |
| Lynds Dark Nebula 1630 | 1 |
How this entity was disambiguated
This entity first appeared as the object of triple T1092381 — resolving that mention is where its identity was fixed. The disambiguator weighed these candidate entities and picked the highlighted one (or “None”, minting a new entity). This is how homonymy is resolved: the same surface form can point to different entities.
NED1
Entity disambiguation (via context triple)
gpt-5-mini-2025-08-07
Target entity: Horsehead Nebula Context triple: [Orion, hasDeepSkyObject, Horsehead Nebula]
-
A.
Eagle Nebula
The Eagle Nebula is a famous star-forming region in the Milky Way best known for the "Pillars of Creation," towering columns of gas and dust captured in iconic Hubble Space Telescope images.
-
B.
Orion Nebula
The Orion Nebula is a bright, nearby stellar nursery where new stars and planetary systems are actively forming within the constellation Orion.
-
C.
Omega Nebula
The Omega Nebula is a bright, star-forming emission nebula and H II region located in the constellation Sagittarius, known for its distinctive swan-like shape and rich young star clusters.
-
D.
Rosette Nebula
The Rosette Nebula is a large, circular emission nebula and active star-forming region located in the Milky Way, notable for its striking rose-like appearance in astrophotography.
-
E.
Trifid Nebula
The Trifid Nebula is a bright, star-forming emission and reflection nebula in the constellation Sagittarius, notable for its three-lobed appearance created by dark dust lanes.
- F. None of above. chosen
- G. Unsure - the case is ambiguous/there is not enough information to decide.
NED2
Entity disambiguation (via description)
gpt-5-mini-2025-08-07
Target entity: Horsehead Nebula Target entity description: The Horsehead Nebula is a dark molecular cloud in the constellation Orion, famous for its distinctive horse-head shape silhouetted against a bright emission nebula.
-
A.
Eagle Nebula
The Eagle Nebula is a famous star-forming region in the Milky Way best known for the "Pillars of Creation," towering columns of gas and dust captured in iconic Hubble Space Telescope images.
-
B.
Orion Nebula
The Orion Nebula is a bright, nearby stellar nursery where new stars and planetary systems are actively forming within the constellation Orion.
-
C.
Omega Nebula
The Omega Nebula is a bright, star-forming emission nebula and H II region located in the constellation Sagittarius, known for its distinctive swan-like shape and rich young star clusters.
-
D.
Rosette Nebula
The Rosette Nebula is a large, circular emission nebula and active star-forming region located in the Milky Way, notable for its striking rose-like appearance in astrophotography.
-
E.
Trifid Nebula
The Trifid Nebula is a bright, star-forming emission and reflection nebula in the constellation Sagittarius, notable for its three-lobed appearance created by dark dust lanes.
- F. None of above. chosen
Statements (48)
| Predicate | Object |
|---|---|
| instanceOf |
astronomical object
ⓘ
dark nebula ⓘ interstellar cloud ⓘ molecular cloud ⓘ |
| alsoKnownAs | Barnard 33 ⓘ |
| angularSize | about 8 arcminutes by 6 arcminutes ⓘ |
| apparentMagnitudeV | 6.8 ⓘ |
| bestSeenFrom |
Northern Hemisphere
ⓘ
linked to:
Northern Celestial Hemisphere
|
| catalogCode | B33 ⓘ |
| composition |
cold molecular gas
ⓘ
interstellar dust ⓘ |
| contains |
dense clumps of gas
ⓘ
star-forming regions ⓘ |
| declination | −02° 27′ 30″ ⓘ |
| discoveredBy | Williamina Fleming ⓘ |
| discoveryYear | 1888 ⓘ |
| distanceFromEarth |
about 1375 light-years
ⓘ
about 420 parsecs ⓘ |
| dustContent | high ⓘ |
| emissionMechanismOfBackground | hydrogen recombination in IC 434 ⓘ |
| featuredIn | many astronomical catalogs ⓘ |
| galacticLatitude | −17.4 ⓘ |
| galacticLongitude | 206.9 ⓘ |
| gasDensity | relatively high for interstellar medium ⓘ |
| hostGalaxy | Milky Way ⓘ |
| ionizingSourceOfBackground |
Sigma Orionis
ⓘ
linked to:
σ Orionis cluster
|
| locatedIn |
Milky Way
ⓘ
Orion Belt region ⓘ
linked to:
Orion constellation
Orion Molecular Cloud Complex ⓘ |
| locatedInConstellation | Orion ⓘ |
| near |
Flame Nebula
ⓘ
NGC 2024 ⓘ |
| notableFor |
distinctive dark outline
ⓘ
popular astrophotography target ⓘ |
| observationalDifficulty | requires dark skies and imaging ⓘ |
| observedIn |
infrared wavelengths
ⓘ
optical wavelengths ⓘ radio wavelengths ⓘ |
| partOf | IC 434 region ⓘ |
| reddeningEffect | strong extinction of background light ⓘ |
| regionType | star-forming region ⓘ |
| rightAscension | 05h 40m 59s ⓘ |
| shapeDescription | horse-head silhouette ⓘ |
| silhouettedAgainst |
IC 434
ⓘ
linked to:
Barnard 33
|
| spectralFeatures | molecular emission lines ⓘ |
| temperature | very cold ⓘ |
| typeOfCloud | Bok globule-like structure ⓘ |
| visibleNear | Alnitak ⓘ |
How these facts were elicited
The pipeline generated the facts above by prompting gpt-5.1 with this entity's name + description and the instruction below.
Instruction
You are a knowledge base construction expert. Given a subject entity and a description of it, return factual statements that you know for the subject as a JSON list of dictionaries(triples), where keys must be "subject", "predicate" and "object". The number of facts may be very high, between 25 to 50 or more, for very popular subjects. For less popular subjects, the number of facts can be very low, like 5 or 10. # Requirements - If you don't know the subject at all, return an empty list. - If the subject is not a named entity, return an empty list. - Include at least one triple where predicate is "instanceOf". - Do not get too wordy. - Separate several objects into multiple triples with one object.
Input
Subject: Horsehead Nebula Description of subject: The Horsehead Nebula is a dark molecular cloud in the constellation Orion, famous for its distinctive horse-head shape silhouetted against a bright emission nebula.
Referenced by (21)
Full triples — surface form annotated when it differs from this entity's canonical label.
linked to: Horsehead Nebula
linked to: Horsehead Nebula
subject linked to:
Orion constellation
linked to: Horsehead Nebula
subject linked to:
NGC 2023 reflection nebula
linked to: Horsehead Nebula
subject linked to:
NGC 2023 reflection nebula
linked to: Horsehead Nebula
linked to: Horsehead Nebula
linked to: Horsehead Nebula
linked to: Horsehead Nebula