NGC 2251
E564389
NGC 2251 is an open star cluster located in the constellation Monoceros, observed as a loose grouping of stars within the Milky Way.
All labels observed (1)
| Label | Occurrences |
|---|---|
| NGC 2251 canonical | 2 |
How this entity was disambiguated
This entity first appeared as the object of triple T5775490 — 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: NGC 2251 Context triple: [Monoceros, contains, NGC 2251]
-
A.
NGC 221
NGC 221 is a compact dwarf elliptical galaxy in the Local Group, best known as the bright satellite galaxy M32 orbiting the Andromeda Galaxy.
-
B.
NGC 2232
NGC 2232 is an open star cluster located in the constellation Monoceros, notable for its relatively young, bright stars.
-
C.
NGC 2207
NGC 2207 is a large spiral galaxy in the constellation Canis Major, notable for its dramatic gravitational interaction and ongoing collision with the nearby galaxy IC 2163.
-
D.
NGC 224
NGC 224 is the Andromeda Galaxy, a massive spiral galaxy and the closest major galactic neighbor to the Milky Way.
-
E.
NGC 2301
NGC 2301 is a bright open star cluster located in the constellation Monoceros, known for its rich population of young, blue stars.
- 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: NGC 2251 Target entity description: NGC 2251 is an open star cluster located in the constellation Monoceros, observed as a loose grouping of stars within the Milky Way.
-
A.
NGC 221
NGC 221 is a compact dwarf elliptical galaxy in the Local Group, best known as the bright satellite galaxy M32 orbiting the Andromeda Galaxy.
-
B.
NGC 2232
NGC 2232 is an open star cluster located in the constellation Monoceros, notable for its relatively young, bright stars.
-
C.
NGC 2207
NGC 2207 is a large spiral galaxy in the constellation Canis Major, notable for its dramatic gravitational interaction and ongoing collision with the nearby galaxy IC 2163.
-
D.
NGC 224
NGC 224 is the Andromeda Galaxy, a massive spiral galaxy and the closest major galactic neighbor to the Milky Way.
-
E.
NGC 2301
NGC 2301 is a bright open star cluster located in the constellation Monoceros, known for its rich population of young, blue stars.
- F. None of above. chosen
Statements (27)
| Predicate | Object |
|---|---|
| instanceOf | open star cluster ⓘ |
| angularSize | ~10 arcminutes ⓘ |
| apparentMagnitudeV | ~7.0 ⓘ |
| approximateAge | hundreds of millions of years (order of magnitude) ⓘ |
| belongsTo |
Milky Way disk
ⓘ
linked to:
Galactic disk
|
| bestObservationSeason | winter ⓘ |
| bestSeenFromHemisphere | Northern Hemisphere ⓘ |
| catalogueDesignation |
C 0631+083
ⓘ
NGC 2251 ⓘ OCL 515 ⓘ |
| declination | +08° 20′ ⓘ |
| discoveredBy | William Herschel ⓘ |
| discoveryDate | 1785 ⓘ |
| distanceFromEarth |
~3,000 light-years
ⓘ
~900 parsecs ⓘ |
| hasColorIndex | indicates moderately evolved stellar population ⓘ |
| hasStellarPopulation |
giant stars
ⓘ
main-sequence stars ⓘ |
| hasType | Galactic open cluster ⓘ |
| locatedIn |
constellation Monoceros
ⓘ
linked to:
Monoceros
|
| locatedInConstellation | Monoceros ⓘ |
| locatedInGalaxy | Milky Way ⓘ |
| memberOf | New General Catalogue ⓘ |
| observedAs | loose grouping of stars ⓘ |
| rightAscension | 06h 34m ⓘ |
| visibleWith |
binoculars under dark skies
ⓘ
small telescope ⓘ |
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: NGC 2251 Description of subject: NGC 2251 is an open star cluster located in the constellation Monoceros, observed as a loose grouping of stars within the Milky Way.
Referenced by (2)
Full triples — surface form annotated when it differs from this entity's canonical label.