Triangulum Galaxy
E20155
The Triangulum Galaxy is a nearby spiral galaxy in the Local Group, notable as one of the closest large galaxies to the Milky Way and a companion to the Andromeda Galaxy.
All labels observed (5)
| Label | Occurrences |
|---|---|
| Triangulum Galaxy canonical | 11 |
| M33 | 6 |
| Messier 33 | 4 |
| Triangulum | 2 |
| Triangulum Galaxy (M33) | 1 |
How this entity was disambiguated
This entity first appeared as the object of triple T156305 — 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: Triangulum Galaxy Context triple: [Milky Way, neighborOf, Triangulum Galaxy]
-
A.
Andromeda Galaxy
The Andromeda Galaxy is the nearest large spiral galaxy to the Milky Way and is on a collision course to eventually merge with it.
-
B.
Milky Way
The Milky Way is the barred spiral galaxy that contains our Solar System and hundreds of billions of other stars.
-
C.
Milky Way center
The Milky Way center is the dense, energetic core of our galaxy, hosting a supermassive black hole surrounded by stars, gas, and dust.
-
D.
Orion Arm
The Orion Arm is a minor spiral arm of the Milky Way galaxy that contains our Solar System and many of the stars visible in the night sky.
-
E.
Pleiades
The Pleiades are a famous open star cluster in the constellation Taurus, often known as the Seven Sisters in Greek mythology.
- 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: Triangulum Galaxy Target entity description: The Triangulum Galaxy is a nearby spiral galaxy in the Local Group, notable as one of the closest large galaxies to the Milky Way and a companion to the Andromeda Galaxy.
-
A.
Andromeda Galaxy
The Andromeda Galaxy is the nearest large spiral galaxy to the Milky Way and is on a collision course to eventually merge with it.
-
B.
Milky Way
The Milky Way is the barred spiral galaxy that contains our Solar System and hundreds of billions of other stars.
-
C.
Milky Way center
The Milky Way center is the dense, energetic core of our galaxy, hosting a supermassive black hole surrounded by stars, gas, and dust.
-
D.
Orion Arm
The Orion Arm is a minor spiral arm of the Milky Way galaxy that contains our Solar System and many of the stars visible in the night sky.
-
E.
Pleiades
The Pleiades are a famous open star cluster in the constellation Taurus, often known as the Seven Sisters in Greek mythology.
- F. None of above. chosen
Statements (48)
| Predicate | Object |
|---|---|
| instanceOf |
Local Group member
ⓘ
galaxy ⓘ spiral galaxy ⓘ |
| alsoKnownAs |
Triangulum Galaxy
ⓘ
surface form:
M33
Triangulum Galaxy ⓘ
surface form:
Messier 33
NGC 598 ⓘ |
| angularSize | approximately 70 by 40 arcminutes ⓘ |
| apparentMagnitudeV | 5.7 ⓘ |
| belongsTo |
Andromeda subgroup
ⓘ
surface form:
Andromeda subgroup of the Local Group
|
| canBeSeenWith | binoculars under dark skies ⓘ |
| catalog |
Messier catalogue
ⓘ
New General Catalogue ⓘ |
| companionOf | Andromeda Galaxy ⓘ |
| contains | large reservoirs of neutral hydrogen ⓘ |
| declination | +30° 39′ 36″ ⓘ |
| diameter | about 60,000 light-years ⓘ |
| discoveredBy | Giovanni Battista Hodierna ⓘ |
| discoveryYear | 1654 ⓘ |
| distanceFromEarth |
about 0.9 megaparsecs
ⓘ
about 3 million light-years ⓘ |
| galaxyType | unbarred spiral galaxy ⓘ |
| gasRich | true ⓘ |
| hasHIIRegion | NGC 604 ⓘ |
| hasSatelliteGalaxy | Pisces Dwarf Galaxy ⓘ |
| hasSupernovaRemnant | multiple known supernova remnants ⓘ |
| isGravitationallyBoundTo | likely Andromeda Galaxy ⓘ |
| isThirdLargestIn | Local Group ⓘ |
| liesInDirectionOf | Northern sky ⓘ |
| locatedInConstellation |
Triangulum Galaxy
self-linksurface differs
ⓘ
surface form:
Triangulum
|
| mass | about 5×10^10 solar masses ⓘ |
| memberOf | Local Group ⓘ |
| metallicity | sub-solar average metallicity ⓘ |
| morphologicalType | SA(s)cd ⓘ |
| notableFeature |
high star formation rate
ⓘ
rich in H II regions ⓘ well-defined spiral structure ⓘ |
| observedIn |
infrared wavelengths
ⓘ
optical wavelengths ⓘ radio wavelengths ⓘ ultraviolet wavelengths ⓘ |
| oneOfClosestLargeGalaxiesTo | Milky Way ⓘ |
| radialVelocity | about −179 km/s ⓘ |
| redshift | z ≈ −0.000597 ⓘ |
| rightAscension | 01h 33m 50.9s ⓘ |
| rotationCurve | used to study dark matter distribution ⓘ |
| starFormationRate | about 0.5–1 solar masses per year ⓘ |
| stellarMass | about 3–6×10^9 solar masses ⓘ |
| usedAs | calibrator for the extragalactic distance scale ⓘ |
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: Triangulum Galaxy Description of subject: The Triangulum Galaxy is a nearby spiral galaxy in the Local Group, notable as one of the closest large galaxies to the Milky Way and a companion to the Andromeda Galaxy.
Referenced by (24)
Full triples — surface form annotated when it differs from this entity's canonical label.
this entity surface form:
Messier 33
this entity surface form:
M33
this entity surface form:
Triangulum
this entity surface form:
Messier 33
this entity surface form:
M33
this entity surface form:
M33
this entity surface form:
Messier 33
this entity surface form:
Triangulum
this entity surface form:
M33
this entity surface form:
M33
this entity surface form:
M33