IM Pegasi
E817765
IM Pegasi is a nearby RS Canum Venaticorum-type binary star system in the constellation Pegasus, notable for its strong radio emissions and use as the guide star for the Gravity Probe B relativity experiment.
All labels observed (2)
How this entity was disambiguated
This entity first appeared as the object of triple T9743267 — 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: IM Pegasi Context triple: [Gravity Probe B, guideStar, IM Pegasi]
-
A.
Epsilon Scuti
Epsilon Scuti is a relatively faint star located in the small southern constellation Scutum.
-
B.
Zeta Tucanae
Zeta Tucanae is a main-sequence F-type star located in the southern constellation Tucana, visible to the naked eye from dark-sky locations.
-
C.
Gamma Microscopii
Gamma Microscopii is a yellow giant star in the southern constellation Microscopium, notable as its most luminous visible member.
-
D.
Rho Tucanae
Rho Tucanae is a star located in the southern constellation Tucana.
-
E.
Beta Scuti
Beta Scuti is a prominent giant star in the constellation Scutum, notable as one of its brightest members.
- 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: IM Pegasi Target entity description: IM Pegasi is a nearby RS Canum Venaticorum-type binary star system in the constellation Pegasus, notable for its strong radio emissions and use as the guide star for the Gravity Probe B relativity experiment.
-
A.
Epsilon Scuti
Epsilon Scuti is a relatively faint star located in the small southern constellation Scutum.
-
B.
Zeta Tucanae
Zeta Tucanae is a main-sequence F-type star located in the southern constellation Tucana, visible to the naked eye from dark-sky locations.
-
C.
Gamma Microscopii
Gamma Microscopii is a yellow giant star in the southern constellation Microscopium, notable as its most luminous visible member.
-
D.
Rho Tucanae
Rho Tucanae is a star located in the southern constellation Tucana.
-
E.
Beta Scuti
Beta Scuti is a prominent giant star in the constellation Scutum, notable as one of its brightest members.
- F. None of above. chosen
Statements (47)
| Predicate | Object |
|---|---|
| instanceOf |
RS Canum Venaticorum variable star system
ⓘ
binary star system ⓘ radio star ⓘ |
| activityType | chromospherically active binary ⓘ |
| apparentMagnitudeV | ~5.7 ⓘ |
| belongsToClass | RS CVn binaries with strong magnetic activity ⓘ |
| catalogDesignation |
HD 216489
ⓘ
HIP 112997 ⓘ HR 8703 ⓘ |
| constellation | Pegasus ⓘ |
| coordinateReferenceRole | astrometric reference source for Gravity Probe B ⓘ |
| declination | +16° 50′ (approx) ⓘ |
| distanceFromEarth |
~29 parsecs
ⓘ
~96 light-years ⓘ |
| emission |
X-ray emission
ⓘ
strong radio emission ⓘ |
| hemisphere | northern celestial hemisphere ⓘ |
| importanceInAstrophysics | benchmark RS CVn radio emitter ⓘ |
| importanceInRelativityTests | primary guide star for Gravity Probe B mission ⓘ |
| lightCurveBehavior | quasi-periodic variability ⓘ |
| luminosityClassPrimary | giant ⓘ |
| magneticActivity |
flaring
ⓘ
strong starspots ⓘ |
| massPrimary | >1 solar mass ⓘ |
| massSecondary | ~1 solar mass (approx) ⓘ |
| observedBy |
Hubble Space Telescope (astrometric context for GP-B)
ⓘ
linked to:
Hubble Space Telescope Fine Guidance Sensors
Very Long Baseline Interferometry (VLBI) arrays ⓘ
linked to:
Very Long Baseline Interferometry
|
| orbitalEccentricity | low ⓘ |
| orbitalPeriod | ~24.65 days ⓘ |
| parallax | ~34 milliarcseconds ⓘ |
| primaryStarEvolutionaryStage | evolved K-type giant ⓘ |
| radioStructure | compact, variable radio source ⓘ |
| radiusPrimary | >10 solar radii (approx) ⓘ |
| rightAscension | 22h 53m 02s (approx) ⓘ |
| secondaryStarEvolutionaryStage | near main sequence ⓘ |
| spectralTypePrimary | K2III ⓘ |
| spectralTypeSecondary | G-type main-sequence star ⓘ |
| systemType | close binary ⓘ |
| usedAsGuideStarFor |
Gravity Probe B
ⓘ
linked to:
Gravity Probe B experiment
|
| usedFor | high-precision astrometry ⓘ |
| usedInExperiment | test of general relativity with Gravity Probe B ⓘ |
| usedToMeasure |
frame-dragging effect
ⓘ
geodetic effect ⓘ |
| variabilityCause | starspots and rotation of active components ⓘ |
| variableStarDesignation |
IM Peg
ⓘ
linked to:
IM Pegasi
|
| variableStarType | RS Canum Venaticorum ⓘ |
| visibility | naked-eye star under good conditions ⓘ |
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: IM Pegasi Description of subject: IM Pegasi is a nearby RS Canum Venaticorum-type binary star system in the constellation Pegasus, notable for its strong radio emissions and use as the guide star for the Gravity Probe B relativity experiment.
Referenced by (3)
Full triples — surface form annotated when it differs from this entity's canonical label.