Cepheid variables
E581535
Cepheid variables are pulsating stars whose regular brightness variations make them crucial standard candles for measuring cosmic distances and mapping galactic structure.
All labels observed (6)
| Label | Occurrences |
|---|---|
| Cepheid variable stars | 2 |
| Cepheid variables canonical | 2 |
| Cepheids | 1 |
| Classical Cepheids | 1 |
| Type I Cepheid | 1 |
| Type II Cepheids | 1 |
How this entity was disambiguated
This entity first appeared as the object of triple T6287075 — 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: Cepheid variables Context triple: [Galactic thin disk, isTracedBy, Cepheid variables]
-
A.
Cepheid
Cepheid is a molecular diagnostics company known for its rapid, automated PCR-based testing systems used in clinical and research settings.
-
B.
RR Lyrae variable stars
RR Lyrae variable stars are old, low-mass pulsating stars used as standard candles to measure distances within the Milky Way and nearby galaxies.
-
C.
Baade’s star
Baade’s star is a luminous, variable star in the Andromeda Galaxy notable for its role in Walter Baade’s work refining the cosmic distance scale.
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D.
Delta Scuti
Delta Scuti is a variable star in the constellation Scutum, serving as the prototype of the Delta Scuti class of short-period pulsating stars.
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E.
UY Scuti
UY Scuti is a 2021 studio album by Nigerian rapper and singer Olamide that blends Afrobeats, hip-hop, and pop influences.
- 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: Cepheid variables Target entity description: Cepheid variables are pulsating stars whose regular brightness variations make them crucial standard candles for measuring cosmic distances and mapping galactic structure.
-
A.
Cepheid
Cepheid is a molecular diagnostics company known for its rapid, automated PCR-based testing systems used in clinical and research settings.
-
B.
RR Lyrae variable stars
RR Lyrae variable stars are old, low-mass pulsating stars used as standard candles to measure distances within the Milky Way and nearby galaxies.
-
C.
Baade’s star
Baade’s star is a luminous, variable star in the Andromeda Galaxy notable for its role in Walter Baade’s work refining the cosmic distance scale.
-
D.
Delta Scuti
Delta Scuti is a variable star in the constellation Scutum, serving as the prototype of the Delta Scuti class of short-period pulsating stars.
-
E.
UY Scuti
UY Scuti is a 2021 studio album by Nigerian rapper and singer Olamide that blends Afrobeats, hip-hop, and pop influences.
- F. None of above. chosen
Statements (51)
| Predicate | Object |
|---|---|
| instanceOf |
class of variable stars
ⓘ
standard candles ⓘ |
| distinguishedBy |
correlation between pulsation period and intrinsic luminosity
ⓘ
regular, predictable light curves ⓘ |
| exhibits |
periodic brightness variations
ⓘ
radial pulsations ⓘ |
| hasAlternativeName |
Cepheid variable stars
ⓘ
Cepheids ⓘ
linked to:
Cepheid variables
|
| hasCauseOfPulsation |
kappa mechanism
ⓘ
opacity changes in partial ionization zones ⓘ |
| hasCauseOfVariability | pulsation of stellar envelope ⓘ |
| hasDiscovery | period–luminosity relation discovered by Henrietta Swan Leavitt ⓘ |
| hasKeyProperty |
period–color relation
ⓘ
period–luminosity relation ⓘ period–radius relation ⓘ |
| hasLightCurveShape | sawtooth-like in many cases ⓘ |
| hasLuminosityClass | I (supergiant) ⓘ |
| hasPhaseRelation | maximum brightness occurs near minimum radius ⓘ |
| hasSpectralTypeRange |
F-type supergiants
ⓘ
G-type supergiants ⓘ |
| hasSubClass |
Anomalous Cepheids
ⓘ
Classical Cepheids ⓘ
linked to:
Cepheid variables
Type II Cepheids ⓘ
linked to:
Cepheid variables
|
| hasTypicalAbsoluteMagnitudeRange | about −2 to −6 in V band ⓘ |
| hasTypicalAgeRange | tens to hundreds of millions of years (Classical Cepheids) ⓘ |
| hasTypicalAmplitudeRange | about 0.1 to 2 magnitudes in visible light ⓘ |
| hasTypicalMassRange | about 3 to 15 solar masses (Classical Cepheids) ⓘ |
| hasTypicalPeriodRange | 1 to 100 days ⓘ |
| hasTypicalTemperatureVariation | several hundred to a few thousand Kelvin over a cycle ⓘ |
| importantFor | establishing the first rung of the cosmic distance ladder ⓘ |
| modeledBy | stellar pulsation theory ⓘ |
| namedAfter |
Delta Cephei
ⓘ
linked to:
δ Cephei
|
| observedIn |
Large Magellanic Cloud
ⓘ
Milky Way ⓘ Small Magellanic Cloud ⓘ many nearby galaxies ⓘ |
| periodLuminosityRelationPublishedIn | 1912 ⓘ |
| requiresForAccurateUse |
corrections for interstellar extinction
ⓘ
metallicity corrections ⓘ |
| traces |
older stellar populations (Type II Cepheids)
ⓘ
young stellar populations (Classical Cepheids) ⓘ |
| typicallyFoundIn |
irregular galaxies
ⓘ
spiral galaxies ⓘ |
| usedAs | primary distance indicators ⓘ |
| usedFor |
calibrating Type Ia supernova luminosities
ⓘ
calibrating the extragalactic distance scale ⓘ determining the Hubble constant ⓘ mapping galactic structure ⓘ measuring distances to nearby galaxies ⓘ measuring distances within the Milky Way ⓘ tracing spiral arms in disk galaxies ⓘ |
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: Cepheid variables Description of subject: Cepheid variables are pulsating stars whose regular brightness variations make them crucial standard candles for measuring cosmic distances and mapping galactic structure.
Referenced by (8)
Full triples — surface form annotated when it differs from this entity's canonical label.
linked to: Cepheid variables
linked to: Cepheid variables
linked to: Cepheid variables
linked to: Cepheid variables
linked to: Cepheid variables
linked to: Cepheid variables