Messier 51
E493645
Messier 51, also known as the Whirlpool Galaxy, is a famous face-on spiral galaxy in the constellation Canes Venatici noted for its striking structure and interaction with a companion galaxy.
All labels observed (5)
| Label | Occurrences |
|---|---|
| M51 | 3 |
| Whirlpool Galaxy | 3 |
| Messier 51 canonical | 2 |
| NGC 5194 | 1 |
| spiralGalaxy M51 | 1 |
How this entity was disambiguated
This entity first appeared as the object of triple T4648493 — 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: Messier 51 Context triple: [Messier catalogue, contains, Messier 51]
-
A.
Messier 81
Messier 81 is a prominent, nearby grand-design spiral galaxy in the constellation Ursa Major, notable for its brightness and well-defined structure.
-
B.
Messier 110
Messier 110 is a dwarf elliptical satellite galaxy of the Andromeda Galaxy located in the Local Group.
-
C.
Triangulum Galaxy
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.
-
D.
Messier 32
Messier 32 is a compact dwarf elliptical galaxy that is a satellite of the Andromeda Galaxy in the Local Group.
-
E.
NGC 2403
NGC 2403 is a nearby spiral galaxy in the constellation Camelopardalis, notable for its active star formation and numerous observed supernovae.
- 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: Messier 51 Target entity description: Messier 51, also known as the Whirlpool Galaxy, is a famous face-on spiral galaxy in the constellation Canes Venatici noted for its striking structure and interaction with a companion galaxy.
-
A.
Messier 81
Messier 81 is a prominent, nearby grand-design spiral galaxy in the constellation Ursa Major, notable for its brightness and well-defined structure.
-
B.
Messier 110
Messier 110 is a dwarf elliptical satellite galaxy of the Andromeda Galaxy located in the Local Group.
-
C.
Triangulum Galaxy
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.
-
D.
Messier 32
Messier 32 is a compact dwarf elliptical galaxy that is a satellite of the Andromeda Galaxy in the Local Group.
-
E.
NGC 2403
NGC 2403 is a nearby spiral galaxy in the constellation Camelopardalis, notable for its active star formation and numerous observed supernovae.
- F. None of above. chosen
Statements (46)
| Predicate | Object |
|---|---|
| instanceOf |
interacting galaxy system
ⓘ
spiral galaxy ⓘ |
| alsoKnownAs |
M51
ⓘ
linked to:
Messier 51
M51a ⓘ NGC 5194 ⓘ
linked to:
Messier 51
Whirlpool Galaxy ⓘ
linked to:
Messier 51
|
| apparentMagnitudeV | 8.4 ⓘ |
| apparentSize | 11.0 × 7.8 arcminutes ⓘ |
| belongsToGalaxyGroup |
Canes Venatici II Group
ⓘ
M51 Group ⓘ |
| bestSeenInMonth | May ⓘ |
| cataloguedBy | Charles Messier ⓘ |
| contains | supermassive black hole at its center ⓘ |
| declination | +47° 11′ 43″ ⓘ |
| discoveredBy | Charles Messier ⓘ |
| discoveryDate | 1773 ⓘ |
| distanceFromEarth |
about 23 million light-years
ⓘ
about 7 megaparsecs ⓘ |
| galaxyType | grand-design spiral galaxy ⓘ |
| hasCompanionGalaxy |
M51b
ⓘ
NGC 5195 ⓘ |
| hasSupernova |
SN 1994I
ⓘ
SN 2005cs ⓘ SN 2011dh ⓘ |
| isPopularTargetFor |
amateur astronomers
ⓘ
astrophotography ⓘ |
| locatedInConstellation | Canes Venatici ⓘ |
| messierNumber | 51 ⓘ |
| morphologicalType | SA(s)bc pec ⓘ |
| ngcNumber | 5194 ⓘ |
| notableFor |
active star formation in spiral arms
ⓘ
interaction with companion galaxy NGC 5195 ⓘ prominent spiral arms ⓘ well-defined dust lanes ⓘ |
| observedByTelescope |
Chandra X-ray Observatory
ⓘ
Hubble Space Telescope ⓘ Spitzer Space Telescope ⓘ |
| observedIn |
X-ray wavelengths
ⓘ
optical wavelengths ⓘ radio wavelengths ⓘ |
| orientation | face-on ⓘ |
| partOf | local volume of the universe ⓘ |
| radialVelocity | 463 km/s ⓘ |
| redshift | 0.001544 ⓘ |
| rightAscension | 13h 29m 52.7s ⓘ |
| visibleFromHemisphere | Northern Hemisphere ⓘ |
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: Messier 51 Description of subject: Messier 51, also known as the Whirlpool Galaxy, is a famous face-on spiral galaxy in the constellation Canes Venatici noted for its striking structure and interaction with a companion galaxy.
Referenced by (10)
Full triples — surface form annotated when it differs from this entity's canonical label.
linked to: Messier 51
linked to: Messier 51
linked to: Messier 51
linked to: Messier 51
linked to: Messier 51
linked to: Messier 51
linked to: Messier 51
linked to: Messier 51