NGC 7009
E867057
NGC 7009, also known as the Saturn Nebula, is a bright planetary nebula notable for its ringed, Saturn-like appearance in the constellation Aquarius.
All labels observed (1)
| Label | Occurrences |
|---|---|
| NGC 7009 canonical | 2 |
How this entity was disambiguated
This entity first appeared as the object of triple T10489012 — 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 7009 Context triple: [Aquarius, containsDeepSkyObject, NGC 7009]
-
A.
NGC 7000
NGC 7000 is a large emission nebula in the constellation Cygnus whose shape strikingly resembles the continent of North America.
-
B.
NGC 7320
NGC 7320 is a foreground spiral galaxy in the constellation Pegasus that appears as part of Stephan’s Quintet but is actually much closer to Earth than the other members.
-
C.
NGC 6925
NGC 6925 is a barred spiral galaxy located in the constellation Microscopium.
-
D.
NGC 6809
NGC 6809 is a bright, relatively nearby globular star cluster in the constellation Sagittarius, notable for its loose structure and rich population of ancient stars.
-
E.
NGC 6923
NGC 6923 is a spiral galaxy located in the constellation Microscopium.
- 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 7009 Target entity description: NGC 7009, also known as the Saturn Nebula, is a bright planetary nebula notable for its ringed, Saturn-like appearance in the constellation Aquarius.
-
A.
NGC 7000
NGC 7000 is a large emission nebula in the constellation Cygnus whose shape strikingly resembles the continent of North America.
-
B.
NGC 7320
NGC 7320 is a foreground spiral galaxy in the constellation Pegasus that appears as part of Stephan’s Quintet but is actually much closer to Earth than the other members.
-
C.
NGC 6925
NGC 6925 is a barred spiral galaxy located in the constellation Microscopium.
-
D.
NGC 6809
NGC 6809 is a bright, relatively nearby globular star cluster in the constellation Sagittarius, notable for its loose structure and rich population of ancient stars.
-
E.
NGC 6923
NGC 6923 is a spiral galaxy located in the constellation Microscopium.
- F. None of above. chosen
Statements (48)
| Predicate | Object |
|---|---|
| instanceOf |
emission nebula
ⓘ
planetary nebula ⓘ |
| bestSeenIn | small to medium telescopes ⓘ |
| catalog |
Caldwell catalogue
ⓘ
New General Catalogue ⓘ |
| centralStarEffectiveTemperature | about 82,000 K ⓘ |
| centralStarEvolutionaryStage | white dwarf precursor ⓘ |
| centralStarSpectralType | O-type ⓘ |
| discoveredBy | William Herschel ⓘ |
| discoveryDate | 1782 ⓘ |
| dominantEmissionLine | [O III] ⓘ |
| hasAlternativeName |
Caldwell 55
ⓘ
Saturn Nebula ⓘ |
| hasAngularSize | about 25 arcseconds × 17 arcseconds (main body) ⓘ |
| hasApparentMagnitudeV | 8.0 ⓘ |
| hasApproximateAge | a few thousand years as a planetary nebula ⓘ |
| hasCentralStar | HD 200516 ⓘ |
| hasColor |
bluish
ⓘ
greenish ⓘ |
| hasDeclination | −11° 21′ 48″ ⓘ |
| hasDistanceFromEarth |
about 1400 parsecs
ⓘ
about 4600 light-years ⓘ |
| hasEquinox | J2000 ⓘ |
| hasExpansion | expanding gas shell ⓘ |
| hasGalacticLatitude | −34.6° (approximate) ⓘ |
| hasGalacticLongitude | 37.8° (approximate) ⓘ |
| hasIonizedGas |
helium
ⓘ
hydrogen ⓘ neon ⓘ nitrogen ⓘ oxygen ⓘ |
| hasMorphology |
Saturn-like appearance
ⓘ
elliptical ⓘ ring-like ⓘ |
| hasNotableFeature |
ansae (handle-like extensions)
ⓘ
bright inner shell ⓘ fainter outer envelope ⓘ halo ⓘ jets ⓘ knots ⓘ multiple shells ⓘ |
| hasRightAscension | 21h 04m 10.8s ⓘ |
| isObservableFrom | both hemispheres ⓘ |
| isPartOf |
Milky Way Galaxy
ⓘ
linked to:
Milky Way
|
| isStudiedFor |
ionization structure of nebulae
ⓘ
planetary nebula morphology ⓘ |
| locatedInConstellation | Aquarius ⓘ |
| originatesFrom | ejected outer layers of a dying star ⓘ |
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 7009 Description of subject: NGC 7009, also known as the Saturn Nebula, is a bright planetary nebula notable for its ringed, Saturn-like appearance in the constellation Aquarius.
Referenced by (2)
Full triples — surface form annotated when it differs from this entity's canonical label.