Antlia 2 Dwarf Galaxy
E507881
Antlia 2 Dwarf Galaxy is an extremely diffuse, low-surface-brightness satellite galaxy of the Milky Way, notable for its large size yet faint appearance and recent discovery through Gaia data.
All labels observed (1)
| Label | Occurrences |
|---|---|
| Antlia 2 Dwarf Galaxy canonical | 1 |
How this entity was disambiguated
This entity first appeared as the object of triple T4618749 — 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: Antlia 2 Dwarf Galaxy Context triple: [Milky Way subgroup, hasMember, Antlia 2 Dwarf Galaxy]
-
A.
Reticulum II Dwarf Galaxy
Reticulum II Dwarf Galaxy is an ultra-faint satellite galaxy of the Milky Way notable for its extreme dark matter dominance and unusually high abundance of heavy r-process elements.
-
B.
Canes Venatici II Dwarf Galaxy
Canes Venatici II Dwarf Galaxy is a faint, small satellite galaxy of the Milky Way located in the constellation Canes Venatici and classified as an ultra-faint dwarf spheroidal galaxy.
-
C.
Bootes II Dwarf Galaxy
Bootes II Dwarf Galaxy is a faint, ultra-low-luminosity satellite galaxy of the Milky Way located in the constellation Boötes.
-
D.
Aquarius Dwarf Galaxy
The Aquarius Dwarf Galaxy is a faint, small dwarf irregular galaxy on the outskirts of the Local Group, notable for its low luminosity and sparse stellar population.
-
E.
Draco Dwarf Galaxy
Draco Dwarf Galaxy is a faint, spheroidal satellite galaxy of the Milky Way, notable for its high dark matter content and very low rate of star formation.
- 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: Antlia 2 Dwarf Galaxy Target entity description: Antlia 2 Dwarf Galaxy is an extremely diffuse, low-surface-brightness satellite galaxy of the Milky Way, notable for its large size yet faint appearance and recent discovery through Gaia data.
-
A.
Reticulum II Dwarf Galaxy
Reticulum II Dwarf Galaxy is an ultra-faint satellite galaxy of the Milky Way notable for its extreme dark matter dominance and unusually high abundance of heavy r-process elements.
-
B.
Canes Venatici II Dwarf Galaxy
Canes Venatici II Dwarf Galaxy is a faint, small satellite galaxy of the Milky Way located in the constellation Canes Venatici and classified as an ultra-faint dwarf spheroidal galaxy.
-
C.
Bootes II Dwarf Galaxy
Bootes II Dwarf Galaxy is a faint, ultra-low-luminosity satellite galaxy of the Milky Way located in the constellation Boötes.
-
D.
Aquarius Dwarf Galaxy
The Aquarius Dwarf Galaxy is a faint, small dwarf irregular galaxy on the outskirts of the Local Group, notable for its low luminosity and sparse stellar population.
-
E.
Draco Dwarf Galaxy
Draco Dwarf Galaxy is a faint, spheroidal satellite galaxy of the Milky Way, notable for its high dark matter content and very low rate of star formation.
- F. None of above. chosen
Statements (48)
| Predicate | Object |
|---|---|
| instanceOf |
diffuse galaxy
ⓘ
dwarf galaxy ⓘ low-surface-brightness galaxy ⓘ |
| absoluteMagnitudeV | approximately −9 ⓘ |
| alternativeName | Antlia 2 ⓘ |
| angularPosition | constellation Antlia ⓘ |
| announced | 2018 ⓘ |
| classification | ultra-diffuse-like dwarf galaxy ⓘ |
| darkMatterDominated | true ⓘ |
| discoveredUsing |
Gaia DR2 data
ⓘ
Gaia space observatory ⓘ
linked to:
Gaia observatory
|
| discoveryMethod |
star counts in Gaia data
ⓘ
stellar proper motion analysis ⓘ |
| discoveryTeam | Torrealba et al. ⓘ |
| discoveryYear | 2018 ⓘ |
| distanceFromEarth |
about 130 kiloparsecs
ⓘ
about 420,000 light-years ⓘ |
| distanceFromMilkyWayCenter | about 130 kiloparsecs ⓘ |
| galaxyType | dwarf spheroidal galaxy ⓘ |
| gasContent | gas-poor ⓘ |
| halfLightRadius |
about 2.9 kiloparsecs
ⓘ
about 9,500 light-years ⓘ |
| hasProperty |
extremely diffuse stellar distribution
ⓘ
very low central surface brightness ⓘ |
| hostGalaxy | Milky Way ⓘ |
| locatedIn | Local Group ⓘ |
| locatedInConstellation | Antlia ⓘ |
| luminosityComparison | much fainter than the Large Magellanic Cloud ⓘ |
| massToLightRatio | very high ⓘ |
| memberOf | Milky Way satellite system ⓘ |
| metallicity | low metallicity ⓘ |
| notableFor |
extremely low surface brightness
ⓘ
large physical size despite low luminosity ⓘ recent discovery via Gaia data ⓘ |
| observedWavelength |
near-infrared
ⓘ
optical ⓘ |
| orbitalStatus | bound satellite of the Milky Way ⓘ |
| publication | Torrealba et al. 2019 MNRAS paper ⓘ |
| researchInterest |
constraints on Milky Way halo structure
ⓘ
tests of dark matter distribution in low-surface-brightness dwarfs ⓘ |
| satelliteOf | Milky Way ⓘ |
| sizeComparison | comparable in size to the Large Magellanic Cloud ⓘ |
| starFormationActivity | quiescent ⓘ |
| stellarMass | of order 10^7 solar masses ⓘ |
| stellarPopulation | predominantly old stars ⓘ |
| surfaceBrightness |
extremely low
ⓘ
lower than typical dwarf spheroidal galaxies ⓘ |
| visibility | very faint ⓘ |
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: Antlia 2 Dwarf Galaxy Description of subject: Antlia 2 Dwarf Galaxy is an extremely diffuse, low-surface-brightness satellite galaxy of the Milky Way, notable for its large size yet faint appearance and recent discovery through Gaia data.
Referenced by (1)
Full triples — surface form annotated when it differs from this entity's canonical label.