Reticulum II Dwarf Galaxy
E505721
dark-matter-dominated galaxy
r-process-enhanced galaxy
satellite galaxy of the Milky Way
ultra-faint 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.
All labels observed (2)
| Label | Occurrences |
|---|---|
| Reticulum Dwarf Galaxy | 1 |
| Reticulum II Dwarf Galaxy canonical | 1 |
How this entity was disambiguated
This entity first appeared as the object of triple T4618745 — 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: Reticulum II Dwarf Galaxy Context triple: [Milky Way subgroup, hasMember, Reticulum II Dwarf Galaxy]
-
A.
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.
-
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.
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.
-
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.
Hercules Dwarf Galaxy
Hercules Dwarf Galaxy is a faint, small satellite galaxy of the Milky Way located in the constellation Hercules and classified as a dwarf spheroidal galaxy.
- 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: Reticulum II Dwarf Galaxy Target entity description: 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.
-
A.
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.
-
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.
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.
-
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.
Hercules Dwarf Galaxy
Hercules Dwarf Galaxy is a faint, small satellite galaxy of the Milky Way located in the constellation Hercules and classified as a dwarf spheroidal galaxy.
- F. None of above. chosen
Statements (47)
| Predicate | Object |
|---|---|
| instanceOf |
dark-matter-dominated galaxy
ⓘ
r-process-enhanced galaxy ⓘ satellite galaxy of the Milky Way ⓘ ultra-faint dwarf galaxy ⓘ |
| absoluteMagnitudeV | about −3.6 ⓘ |
| belongsTo |
Milky Way halo
ⓘ
linked to:
Milky Way stellar halo
|
| contains | r-II stars ⓘ |
| declination | approximately −54° ⓘ |
| discoveredBy | Dark Energy Survey ⓘ |
| discoveryMethod | wide-field photometric survey ⓘ |
| discoveryYear | 2015 ⓘ |
| distanceFromMilkyWay |
approximately 30 kiloparsecs
ⓘ
approximately 98,000 light-years ⓘ |
| galaxyType | dSph (dwarf spheroidal) ⓘ |
| hasAlternativeName |
Ret II
ⓘ
Reticulum II ⓘ |
| hasProperty |
chemically homogeneous r-process pattern among enriched stars
ⓘ
compact spatial extent ⓘ contains r-process-enhanced stars ⓘ dynamically dominated by dark matter ⓘ extreme dark matter dominance ⓘ high abundance of r-process elements ⓘ high mass-to-light ratio ⓘ low gas content ⓘ low velocity dispersion of stars ⓘ old stellar population ⓘ very low stellar mass ⓘ very low surface brightness ⓘ very metal-poor stellar population ⓘ |
| locatedIn |
constellation Reticulum
ⓘ
linked to:
Reticulum
|
| luminosityClass | ultra-faint ⓘ |
| memberOf | Local Group ⓘ |
| metallicity | [Fe/H] around −2.5 dex (typical) ⓘ |
| notableFor |
being a prime candidate site of a past neutron star merger
ⓘ
hosting stars with extreme r-process enhancement ⓘ strong indirect evidence for dark matter ⓘ |
| observedIn |
gamma-ray searches for dark matter annihilation
ⓘ
optical wavelengths ⓘ |
| rightAscension | approximately 03h 35m ⓘ |
| satelliteOf | Milky Way ⓘ |
| scientificInterest |
chemical evolution of ultra-faint dwarfs
ⓘ
indirect dark matter detection via gamma rays ⓘ origin of heavy elements beyond iron ⓘ |
| surveyDesignation | DES J0335.6−5403 ⓘ |
| usedFor |
constraints on dark matter particle properties
ⓘ
studies of r-process nucleosynthesis ⓘ tests of galaxy formation at the lowest masses ⓘ |
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: Reticulum II Dwarf Galaxy Description of subject: 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.
Referenced by (2)
Full triples — surface form annotated when it differs from this entity's canonical label.
linked to: Reticulum II Dwarf Galaxy