subsatellite PFS-1
E247686
Subsatellite PFS-1 was a small scientific satellite released into lunar orbit during the Apollo 15 mission to study the Moon’s gravitational and magnetic fields and the particle environment.
All labels observed (3)
| Label | Occurrences |
|---|---|
| Particles and Fields Subsatellite | 1 |
| Particles and Fields Subsatellite 1 | 1 |
| subsatellite PFS-1 canonical | 1 |
How this entity was disambiguated
This entity first appeared as the object of triple T2238461 — 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: subsatellite PFS-1 Context triple: [Apollo 15, carriedInstrument, subsatellite PFS-1]
-
A.
Vanguard 1 satellite
Vanguard 1 satellite is an early American artificial Earth satellite launched in 1958 that became the fourth human-made object in space and the oldest still in orbit, used primarily for geophysical and atmospheric research.
-
B.
GSAT-1
GSAT-1 is an Indian communications satellite that served as the inaugural payload for the Geosynchronous Satellite Launch Vehicle (GSLV) program.
-
C.
PALAPA B1 communications satellite
PALAPA B1 was an Indonesian communications satellite launched in the early 1980s to expand the country's domestic and regional telecommunications capabilities.
-
D.
ANIK C2 communications satellite
ANIK C2 is a Canadian commercial communications satellite used to provide telecommunications and broadcasting services.
-
E.
SCISAT-1
SCISAT-1 is a Canadian scientific satellite dedicated primarily to studying Earth's upper atmosphere and monitoring ozone layer chemistry and related trace gases.
- 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: subsatellite PFS-1 Target entity description: Subsatellite PFS-1 was a small scientific satellite released into lunar orbit during the Apollo 15 mission to study the Moon’s gravitational and magnetic fields and the particle environment.
-
A.
Vanguard 1 satellite
Vanguard 1 satellite is an early American artificial Earth satellite launched in 1958 that became the fourth human-made object in space and the oldest still in orbit, used primarily for geophysical and atmospheric research.
-
B.
GSAT-1
GSAT-1 is an Indian communications satellite that served as the inaugural payload for the Geosynchronous Satellite Launch Vehicle (GSLV) program.
-
C.
PALAPA B1 communications satellite
PALAPA B1 was an Indonesian communications satellite launched in the early 1980s to expand the country's domestic and regional telecommunications capabilities.
-
D.
ANIK C2 communications satellite
ANIK C2 is a Canadian commercial communications satellite used to provide telecommunications and broadcasting services.
-
E.
SCISAT-1
SCISAT-1 is a Canadian scientific satellite dedicated primarily to studying Earth's upper atmosphere and monitoring ozone layer chemistry and related trace gases.
- F. None of above. chosen
Statements (44)
| Predicate | Object |
|---|---|
| instanceOf |
artificial satellite
ⓘ
lunar orbiter ⓘ scientific satellite ⓘ subsatellite ⓘ |
| alternativeName |
Apollo 15 subsatellite
ⓘ
subsatellite PFS-1 ⓘ
surface form:
Particles and Fields Subsatellite
|
| associatedMission | Apollo 15 ⓘ |
| countryOfOperator |
United States of America
ⓘ
surface form:
United States
|
| crewOnboard | no ⓘ |
| deploymentMethod | mechanically ejected from the Service Module in lunar orbit ⓘ |
| destination | lunar orbit ⓘ |
| endOfMission | decayed from lunar orbit and impacted the Moon ⓘ |
| environmentStudied | lunar near-space environment ⓘ |
| epoch | Apollo era ⓘ |
| fieldOfStudy |
geophysics
ⓘ
planetary science ⓘ space physics ⓘ |
| fullName |
subsatellite PFS-1
self-linksurface differs
ⓘ
surface form:
Particles and Fields Subsatellite 1
|
| impactBody | Moon ⓘ |
| launchComplex | Kennedy Space Center Launch Complex 39A ⓘ |
| launchDate | 1971-07-26 ⓘ |
| launchedWith | Apollo 15 ⓘ |
| launchSite | Kennedy Space Center ⓘ |
| launchVehicle | Saturn V ⓘ |
| massClass | small satellite ⓘ |
| missionType |
lunar science
ⓘ
particles and fields investigation ⓘ scientific research ⓘ |
| notableFor | being one of the first dedicated scientific subsatellites deployed in lunar orbit ⓘ |
| operator | NASA ⓘ |
| orbitsCrewedMission | yes ⓘ |
| orbitType | lunar orbit ⓘ |
| primaryBodyOrbited | Moon ⓘ |
| program | Apollo program ⓘ |
| purpose |
study the Moon’s gravitational field
ⓘ
study the Moon’s magnetic field ⓘ study the lunar particle environment ⓘ |
| releaseContext | released in lunar orbit during Apollo 15 mission ⓘ |
| releasedFrom | Apollo 15 Command and Service Module ⓘ |
| scientificObjective |
investigate lunar gravity anomalies
ⓘ
measure charged particles near the Moon ⓘ measure magnetic field variations around the Moon ⓘ |
| spaceAgency | NASA ⓘ |
| spacecraftType | uncrewed spacecraft ⓘ |
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: subsatellite PFS-1 Description of subject: Subsatellite PFS-1 was a small scientific satellite released into lunar orbit during the Apollo 15 mission to study the Moon’s gravitational and magnetic fields and the particle environment.
Referenced by (3)
Full triples — surface form annotated when it differs from this entity's canonical label.
subject surface form:
PFS-1
this entity surface form:
Particles and Fields Subsatellite 1
subject surface form:
PFS-1
this entity surface form:
Particles and Fields Subsatellite