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 | 1 |
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 NERFINISHED ⓘ |
| bestObservationSeason | winter ⓘ |
| bestSeenFromHemisphere | Northern Hemisphere NERFINISHED ⓘ |
| catalogueDesignation |
C 0631+083
ⓘ
NGC 2251 NERFINISHED ⓘ OCL 515 NERFINISHED ⓘ |
| declination | +08° 20′ ⓘ |
| discoveredBy | William Herschel NERFINISHED ⓘ |
| 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 NERFINISHED ⓘ |
| locatedInConstellation | Monoceros NERFINISHED ⓘ |
| locatedInGalaxy | Milky Way NERFINISHED ⓘ |
| memberOf | New General Catalogue NERFINISHED ⓘ |
| 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 (1)
Full triples — surface form annotated when it differs from this entity's canonical label.