Airy Modified ellipsoid
E411948
The Airy Modified ellipsoid is a slightly adjusted version of the Airy ellipsoid used as the reference surface for mapping and geodetic calculations in systems such as the Irish grid reference system.
All labels observed (2)
| Label | Occurrences |
|---|---|
| Airy Modified 1849 ellipsoid | 1 |
| Airy Modified ellipsoid canonical | 1 |
How this entity was disambiguated
This entity first appeared as the object of triple T4073230 — 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: Airy Modified ellipsoid Context triple: [Irish grid reference system, datum, Airy Modified ellipsoid]
-
A.
Earth gravity model
The Earth gravity model is a mathematical representation of Earth's gravitational field used for precise positioning, navigation, and geodetic calculations.
-
B.
Jacobi ellipsoid
A Jacobi ellipsoid is a rotating, self-gravitating fluid body in equilibrium that takes on a triaxial ellipsoidal shape due to its rapid spin.
-
C.
WGS84
WGS84 is the global geodetic reference system and standard coordinate framework used for GPS and most modern mapping applications.
-
D.
Earth Orientation Parameters
Earth Orientation Parameters are a set of time-varying values that precisely describe the irregular rotation and orientation of the Earth in space for applications like navigation, astronomy, and geodesy.
-
E.
Feautrier method
The Feautrier method is a numerical technique used in radiative transfer to stably and accurately solve second-order differential equations for the radiation field in stellar atmospheres and similar media.
- 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: Airy Modified ellipsoid Target entity description: The Airy Modified ellipsoid is a slightly adjusted version of the Airy ellipsoid used as the reference surface for mapping and geodetic calculations in systems such as the Irish grid reference system.
-
A.
Earth gravity model
The Earth gravity model is a mathematical representation of Earth's gravitational field used for precise positioning, navigation, and geodetic calculations.
-
B.
Jacobi ellipsoid
A Jacobi ellipsoid is a rotating, self-gravitating fluid body in equilibrium that takes on a triaxial ellipsoidal shape due to its rapid spin.
-
C.
WGS84
WGS84 is the global geodetic reference system and standard coordinate framework used for GPS and most modern mapping applications.
-
D.
Earth Orientation Parameters
Earth Orientation Parameters are a set of time-varying values that precisely describe the irregular rotation and orientation of the Earth in space for applications like navigation, astronomy, and geodesy.
-
E.
Feautrier method
The Feautrier method is a numerical technique used in radiative transfer to stably and accurately solve second-order differential equations for the radiation field in stellar atmospheres and similar media.
- F. None of above. chosen
Statements (31)
| Predicate | Object |
|---|---|
| instanceOf |
geodetic datum surface
ⓘ
reference ellipsoid ⓘ |
| authority |
Ordnance Survey Ireland headquarters
ⓘ
surface form:
Ordnance Survey of Ireland
Ordnance Survey of Northern Ireland ⓘ |
| basedOn | Airy 1830 ellipsoid ⓘ |
| category |
cartography
ⓘ
geodesy ⓘ |
| coordinateSystemType | ellipsoidal ⓘ |
| datumRealization |
Irish grid reference system
ⓘ
surface form:
Irish Grid datum
OSI 1965 ⓘ |
| differenceFrom | slightly modified parameters from Airy 1830 ⓘ |
| epoch | 1965.0 ⓘ |
| hasFlattening | 0.0033408506415 ⓘ |
| hasInverseFlattening | 299.3249646 ⓘ |
| hasSemiMajorAxis | 6377340.189 m ⓘ |
| hasUnit | metre ⓘ |
| isLocalDatumEllipsoid | true ⓘ |
| optimizedFor | local fit to Ireland ⓘ |
| referenceSurfaceFor | Irish National Grid coordinates ⓘ |
| region | Ireland ⓘ |
| relatedTo | Airy 1830 ellipsoid ⓘ |
| usedBefore | ETRS89-based systems in Ireland ⓘ |
| usedFor |
geodetic calculations
ⓘ
map projection ⓘ topographic mapping ⓘ |
| usedIn |
Irish grid reference system
ⓘ
surface form:
Irish Grid Reference System
Irish grid reference system ⓘ
surface form:
Irish National Grid
Northern Ireland mapping ⓘ Republic of Ireland mapping ⓘ |
| usedInProjectionZone |
Irish grid reference system
ⓘ
surface form:
Ireland Transverse Mercator (legacy grid)
|
| usedWith |
Transverse Mercator
ⓘ
surface form:
Transverse Mercator projection
|
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: Airy Modified ellipsoid Description of subject: The Airy Modified ellipsoid is a slightly adjusted version of the Airy ellipsoid used as the reference surface for mapping and geodetic calculations in systems such as the Irish grid reference system.
Referenced by (2)
Full triples — surface form annotated when it differs from this entity's canonical label.
this entity surface form:
Airy Modified 1849 ellipsoid