M20
E450594
M20 is the Trifid Nebula, a bright and picturesque star-forming emission and reflection nebula located in the constellation Sagittarius.
All labels observed (1)
| Label | Occurrences |
|---|---|
| M20 canonical | 5 |
How this entity was disambiguated
This entity first appeared as the object of triple T4531733 — 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: M20 Context triple: [Messier 20, alsoKnownAs, M20]
-
A.
M20
M20 is a major motorway in South East England connecting London to the Channel Tunnel and the port of Dover.
-
B.
M2
M2 is a major British motorway that connects London with the port town of Dover in Kent, serving as an important route to the Channel ports.
-
C.
M2
M2 is the second line of the Warsaw Metro, running east–west across the city and connecting key districts on both sides of the Vistula River.
-
D.
M2
M2 was the original name of MTV2, a U.S. cable television channel that focused on music videos and youth-oriented programming.
-
E.
M2
M2 is one of the main lines of the Copenhagen Metro, connecting central Copenhagen with key districts and the airport.
- 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: M20 Target entity description: M20 is the Trifid Nebula, a bright and picturesque star-forming emission and reflection nebula located in the constellation Sagittarius.
-
A.
M20
M20 is a major motorway in South East England connecting London to the Channel Tunnel and the port of Dover.
-
B.
M2
M2 was the original name of MTV2, a U.S. cable television channel that focused on music videos and youth-oriented programming.
-
C.
M2
M2 is a major British motorway that connects London with the port town of Dover in Kent, serving as an important route to the Channel ports.
-
D.
M2
M2 is the second line of the Warsaw Metro, running east–west across the city and connecting key districts on both sides of the Vistula River.
-
E.
M2
M2 is one of the main lines of the Copenhagen Metro, connecting central Copenhagen with key districts and the airport.
- F. None of above. chosen
Statements (47)
| Predicate | Object |
|---|---|
| instanceOf |
H II region
ⓘ
Messier object ⓘ NGC object ⓘ emission nebula ⓘ nebula ⓘ reflection nebula ⓘ star-forming region ⓘ |
| alsoKnownAs |
Messier 20
ⓘ
NGC 6514 ⓘ Trifid Nebula ⓘ |
| angularSize | 28 arcminutes ⓘ |
| apparentMagnitudeV | 9.0 ⓘ |
| bestSeenFrom | southern latitudes ⓘ |
| bestSeenIn | small telescopes ⓘ |
| catalog |
Messier catalogue
ⓘ
New General Catalogue ⓘ |
| contains |
Herbig–Haro objects
ⓘ
open star cluster ⓘ protostars ⓘ young massive stars ⓘ |
| declination | −23° 02′ ⓘ |
| discoveredBy | Charles Messier ⓘ |
| discoveryDate | 1764 ⓘ |
| distanceFromEarth |
approximately 1.3 kiloparsecs
ⓘ
approximately 4100 light-years ⓘ |
| dominantEmissionLine | H-alpha ⓘ |
| galacticLatitude | −0.3 degrees (approximate) ⓘ |
| galacticLongitude | 7.0 degrees (approximate) ⓘ |
| hasColor |
blue reflection regions
ⓘ
red emission regions ⓘ |
| hasComponent |
dark nebula lanes
ⓘ
emission nebula region ⓘ reflection nebula region ⓘ |
| hasFeature | three prominent dark dust lanes ⓘ |
| isInDirectionOf |
Galactic Center region
ⓘ
linked to:
Milky Way center
|
| isTargetFor | astrophotography ⓘ |
| liesNear |
Lagoon Nebula
ⓘ
M8 ⓘ |
| locatedIn |
Sagittarius Arm of the Milky Way
ⓘ
linked to:
Sagittarius Arm
|
| locatedInConstellation | Sagittarius ⓘ |
| nameEtymology | called Trifid because of its three-lobed appearance ⓘ |
| observedIn |
infrared wavelengths
ⓘ
optical wavelengths ⓘ radio wavelengths ⓘ |
| partOf | Milky Way ⓘ |
| rightAscension | 18h 02m ⓘ |
| spectralTypeOfIonizingStars | O-type ⓘ |
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: M20 Description of subject: M20 is the Trifid Nebula, a bright and picturesque star-forming emission and reflection nebula located in the constellation Sagittarius.
Referenced by (5)
Full triples — surface form annotated when it differs from this entity's canonical label.