Orcus
E80084
Orcus is a large trans-Neptunian dwarf-planet candidate in the Kuiper Belt, often considered a "twin" of Pluto due to its similar size, orbit, and composition.
All labels observed (2)
How this entity was disambiguated
This entity first appeared as the object of triple T633433 — 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: Orcus Context triple: [Kuiper Belt object, example, Orcus]
-
A.
Crius
Crius is one of the twelve primordial Titans of Greek mythology, associated with the constellations and the cosmic order preceding the Olympian gods.
-
B.
Nausithous
Nausithous is a lesser-known figure in Greek mythology, traditionally named as one of the sons of the nymph Calypso.
-
C.
Tartarus
Tartarus is the deep, gloomy abyss in Greek mythology used as a dungeon of torment and imprisonment for the Titans and other divine enemies.
-
D.
Typhoeus
Typhoeus is a monstrous serpentine giant from Greek mythology, often depicted as a fearsome adversary of Zeus and a symbol of chaotic natural forces.
-
E.
Erinyes
The Erinyes are fearsome chthonic deities of vengeance and retribution in Greek mythology, often depicted as relentless pursuers of those guilty of serious crimes such as murder and oath-breaking.
- 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: Orcus Target entity description: Orcus is a large trans-Neptunian dwarf-planet candidate in the Kuiper Belt, often considered a "twin" of Pluto due to its similar size, orbit, and composition.
-
A.
Crius
Crius is one of the twelve primordial Titans of Greek mythology, associated with the constellations and the cosmic order preceding the Olympian gods.
-
B.
Nausithous
Nausithous is a lesser-known figure in Greek mythology, traditionally named as one of the sons of the nymph Calypso.
-
C.
Tartarus
Tartarus is the deep, gloomy abyss in Greek mythology used as a dungeon of torment and imprisonment for the Titans and other divine enemies.
-
D.
Typhoeus
Typhoeus is a monstrous serpentine giant from Greek mythology, often depicted as a fearsome adversary of Zeus and a symbol of chaotic natural forces.
-
E.
Erinyes
The Erinyes are fearsome chthonic deities of vengeance and retribution in Greek mythology, often depicted as relentless pursuers of those guilty of serious crimes such as murder and oath-breaking.
- F. None of above. chosen
Statements (46)
| Predicate | Object |
|---|---|
| instanceOf |
Kuiper belt object
ⓘ
dwarf-planet candidate ⓘ plutino ⓘ trans-Neptunian object ⓘ |
| absoluteMagnitude | about 2.3 ⓘ |
| albedo | approximately 0.23 ⓘ |
| aphelionDistance | approximately 48.1 astronomical units ⓘ |
| belongsToDynamicalClass |
plutino
ⓘ
resonant Kuiper belt object ⓘ |
| celestialBodyType | icy trans-Neptunian object ⓘ |
| classificationStatus | dwarf-planet candidate ⓘ |
| density | about 1.5 g/cm³ ⓘ |
| discoveredBy |
Chad Trujillo
ⓘ
David L. Rabinowitz ⓘ
surface form:
David Rabinowitz
Michael E. Brown ⓘ |
| discoveryDate | 2004-02-17 ⓘ |
| discoverySite | Palomar Observatory ⓘ |
| eccentricity | about 0.22 ⓘ |
| gravitationallyBoundTo | Sun ⓘ |
| hasAlternativeName |
2004 DW
ⓘ
90482 Orcus (2004 DW) ⓘ |
| hasMeanSurfaceTemperature | around 40–50 K ⓘ |
| hasNumberDesignation | 90482 Orcus ⓘ |
| hasOrbitalCategory | trans-Neptunian region ⓘ |
| hasSatellite | Vanth ⓘ |
| inclination | about 20.6 degrees ⓘ |
| isCandidateFor | dwarf planet status ⓘ |
| locatedIn |
Kuiper Belt
ⓘ
surface form:
Kuiper belt
|
| mass | about 6.4×10^20 kilograms ⓘ |
| meanDiameter | approximately 910 kilometers ⓘ |
| namedAfter | Orcus (Roman god of the underworld) ⓘ |
| observedBy | Hubble Space Telescope ⓘ |
| oftenDescribedAs | twin of Pluto ⓘ |
| orbitalPeriod | approximately 247 Earth years ⓘ |
| orbitalResonanceRatio | 2:3 ⓘ |
| orbitalResonanceWith | Neptune ⓘ |
| orbits | Sun ⓘ |
| perihelionDistance | approximately 30.3 astronomical units ⓘ |
| rotationPeriod | about 10.5 hours ⓘ |
| semiMajorAxis | approximately 39.2 astronomical units ⓘ |
| similarTo | Pluto ⓘ |
| spectralType | neutral to slightly red ⓘ |
| surfaceComposition |
carbonaceous material
ⓘ
water ice ⓘ |
| surfaceFeature | shows water-ice absorption bands in spectrum ⓘ |
| systemType | binary system with Vanth ⓘ |
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: Orcus Description of subject: Orcus is a large trans-Neptunian dwarf-planet candidate in the Kuiper Belt, often considered a "twin" of Pluto due to its similar size, orbit, and composition.
Referenced by (10)
Full triples — surface form annotated when it differs from this entity's canonical label.
subject surface form:
Kuiper Belt object
this entity surface form:
Orcus I
subject surface form:
90482 Orcus